Freewheel and freewheel arrangement

Abstract

Freewheel (1), in particular a clamping roller freewheel, comprising: - a ring element (2), in particular an inner ring or an outer ring, with at least one clamping ramp (3) for clamping a clamping element (4), - one clamping element (4) per clamping ramp (3) which rests against at least one clamping ramp (3), - wherein the at least one clamping ramp (3) has at least a first (5) and a second sub-section (6), - wherein the second sub-area (6) is designed as a force transmission area in such a way that a relative movement between the clamping element (4) and the ring element (2) can be prevented, - wherein the first sub-area (5) is designed as an overload area such that a relative movement between clamping element (4) and ring element (2) can be ensured, thereby preventing a force transmission from the first ring element (2) to the at least one clamping element (4), - wherein the first sub-section (5) allows relative movement between clamping element (4) and ring element (2) by ensuring that at the contact point (A) between clamping element (4) and clamping ramp (3) the tangent of the angle (α) formed between a force (F) to be transmitted and a normal (N1) of the first sub-section (5) arranged on the contact point (A) is greater than or equal to the coefficient of friction (µ) of the materials of the friction pair ring element (2) and clamping element (4).

Description

[0001] The invention relates to a clamping freewheel, in particular a clamping roller freewheel, with a ring element, in particular an inner ring or an outer ring, with at least one clamping ramp for clamping a clamping element, and with one clamping element per clamping ramp that rests against the at least one clamping ramp.

[0002] From DE 103 14 195 A1 a compressor is known which is equipped with a torque limiter and is suitable for use as a coolant compressor in an (air) air conditioning system arranged on a vehicle.

[0003] Furthermore, a roller freewheel is known from DE 10 2009 037 255 A1, which has a cylindrical outer ring with clamping ramps formed on the inner surface, several clamping rollers which are spring-loaded against the clamping ramps, and a cage arranged in the outer ring in a rotationally fixed manner.

[0004] A freewheel, or clamping freewheel, is a directionally controlled clutch and typically consists of an inner and outer ring and a cage with clamping rollers and springs. The clamping freewheel is able to decouple a portion of a drive train from rotational movement in the event of changing load conditions.

[0005] Freewheels are commonly used as backstops or overrunning clutches.

[0006] In a starter freewheel used as an overrunning clutch, springs and clamping rollers or clamping elements are typically used, which are pressed into pockets or against clamping profiles or ramps of an inner or outer ring. Because the clamping elements taper away from the springs in receiving spaces that are partially defined by the clamping profile or ramps, the torque transmitted from the inner ring to the outer ring is greater the more the two rings are rotated relative to each other.

[0007] By selecting a suitable angle of inclination or clamping of the clamping profile, a freewheel is slip-resistant, as it is in a so-called self-locking state. The clamping angle is chosen so that it is less than or equal to the arctangent of the coefficient of sliding friction µ of the two materials rubbing against each other.

[0008] If the clamping angle is chosen to be larger than the arctangent of µ, the freewheel will slip and cannot transmit any forces.

[0009] A starter freewheel is used, for example, in combustion engines for motorcycles with electric starters. To start the combustion engine, an electric motor drives a starter pinion, which is equipped with a freewheel. The starter pinion is typically connected to the inner ring of the freewheel, while the outer ring is usually attached to the alternator.

[0010] The freewheel transmits power via the outer ring to the alternator until the combustion engine ignites. Once the engine ignites, the crankshaft, which is connected to the alternator, is accelerated to a higher speed compared to when the engine was starting.

[0011] The freewheel now decouples the running engine or its crankshaft from the electric starter, so that the started engine does not damage or destroy the starter with excessively high speed.

[0012] The problem of excessively high forces introduced into a freewheel is known from the prior art, which press the clamping elements into the clamping profile or against clamping ramps so jerkily and quickly that they are worn out, leading to the immediate total failure of the freewheel.

[0013] Therefore, the object of the present invention is to provide a freewheel or clamping freewheel and a freewheel arrangement which provides effective protection against excessively high forces introduced into the freewheel or a torque limitation, wherein such a freewheel or such a freewheel arrangement preferably ensures a high level of functional reliability and can be manufactured cost-effectively and with minimal material usage.

[0014] This problem is solved according to the invention by the features of the independent claims. Further advantageous embodiments are the subject of the dependent claims.

[0015] According to the invention, in a first aspect of the present invention, a clamping freewheel, in particular a clamping roller freewheel, comprises a ring element, in particular an inner ring or an outer ring, with at least one clamping ramp or a clamping profile for clamping a clamping element.

[0016] Preferably, the clamping freewheel further comprises a clamping element or a clamping roller per clamping ramp, which rests against the at least one clamping ramp.

[0017] Advantageously, the at least one clamping ramp has at least a first and a second sub-section, the second sub-section preferably being designed as a force transmission section such that relative movement between the clamping element and the ring element is prevented. In this way, the clamping freewheel can transmit a force or torque from an inner ring to an outer ring or vice versa. This makes it possible, for example, to start an internal combustion engine.

[0018] Furthermore, it is advantageous if the first section is designed as an overload zone in such a way that relative movement between the clamping element and the ring element is ensured. This prevents force transmission from the first ring element to the at least one clamping element.

[0019] In other words, it is advantageous if, when a high torque is rapidly or suddenly applied to the freewheel, the clamping elements move from the power transmission range to the overload range. This overload range preferably prevents damage to the entire freewheel or clamping freewheel. If excessively high forces are applied to a freewheel, the clamping elements are pressed so abruptly and rapidly into the clamping profile or against the clamping ramps that they become worn out, which in turn can lead to total failure of the freewheel.

[0020] Furthermore, it is preferred that, during rotation of the ring element for force transmission, the first sub-section follows the second sub-section, so that, preferably in the event of an overload, the clamping element moves from the second sub-section towards the first sub-section. This allows the force transmission between the first sub-section, the at least one clamping ramp, or between the ring element and the clamping element to be interrupted. This interruption protects the freewheel from an overload that could destroy it.

[0021] Preferably, the at least one clamping ramp extends in the circumferential direction. Since the ring elements are generally rotationally symmetrical, they extend in a radial direction and in an axial direction, with the ring elements preferably having the at least one clamping ramp and the associated clamping elements in the direction of their circumference.

[0022] It is also preferred that the first section allows relative movement between the clamping element and the ring element. In this way, no forces or moments can be transmitted that could damage the freewheel.

[0023] Advantageously, the first sub-area allows relative movement between the clamping element and the ring element, preferably by ensuring that at the contact point between the clamping element and the clamping ramp, the tangent of the angle formed between a force to be transmitted and a normal of the first sub-area arranged on the contact point is greater than or equal to the coefficient of friction of the materials of the friction pair ring element and clamping element.

[0024] In simple terms, it is preferred that the first part of the clamping ramp implements the known relationship tanα ≥ µ, thereby releasing the clamping force between the clamping ramp and the ring element, or allowing the clamping element to slide on the clamping ramp. This, in turn, limits the torque / force applied to the ring element by the freewheel, thus providing overload protection.

[0025] It is also preferred that the second section prevents relative movement between the clamping element and the ring element. In this way, forces or moments can be transmitted.

[0026] Preferably, the second sub-area prevents relative movement between the clamping element and the ring element, preferably by ensuring that at the contact point between the clamping element and the clamping ramp, the tangent of the angle formed between a force to be transmitted and a normal of the second sub-area arranged on the contact point is smaller than the coefficient of friction of the materials of the friction pair ring element and clamping element.

[0027] In other words, it is advantageous if the second part of the clamping ramp implements the known relationship tanα < µ, thereby creating a clamping connection between the clamping ramp and the ring element, or rather, causing the clamping element to clamp onto the clamping ramp. This results in the freewheel transmitting the torque / force applied to the ring element.

[0028] Furthermore, it is advantageous if the angle for the first section is greater than 15 degrees, with the angle in the second section preferably being between 3 and 4.5 degrees. These angle ranges enable sliding with tanα ≥ µ or clamping with tanα < µ. In other words, a sliding motion between the clamping element and the clamping ramp or ring element can be easily achieved with an angle greater than 15 degrees, whereas a clamping motion between the clamping element and the clamping ramp or ring element can be ensured with an angle between 3 and 4.5 degrees.

[0029] Furthermore, it is preferred that the ring element be made from a sheet of metal. This allows for simple, cost-effective, and material-saving manufacturing.

[0030] Preferably, the ring element is designed with thin walls. This saves material and therefore costs.

[0031] Furthermore, it is advantageous if the ring element is designed with such thin walls that the hollow cylindrical ring element has a wall thickness outside a clamping ramp that is a fraction of the thickness of a clamping element, preferably less than 0.5 times the thickness of the clamping element, and more preferably less than 0.3 times the thickness of a clamping element. It is also advantageous if the wall thickness at the thickest or thinnest position of the first ring element in the circumferential direction is a fraction of the thickness of a clamping element. This relationship provides a particularly simple and material-saving manufacturing method.

[0032] A second aspect of the present invention comprises a freewheel arrangement with a clamping freewheel, a first ring element, in particular in the configuration of an inner ring or an outer ring, with at least one clamping ramp for clamping a clamping element, and with a second ring element, in particular an outer ring or an inner ring.

[0033] It is expressly pointed out that the features of the clamping freewheel, as mentioned under the first aspect of the present description, can be used individually or in combination in the freewheel arrangement.

[0034] In other words, the features relating to the clamping freewheel mentioned above under the first aspect of the invention can also be combined with further features under the second aspect of the invention.

[0035] Advantageously, the first ring element comprises one clamping element per clamping ramp, which rests against at least one clamping ramp.

[0036] Ideally, at least one clamping ramp has at least a first and a second sub-section.

[0037] Preferably, the first section is designed as an overload zone such that the clamping element moves relative to the at least one clamping ramp, thereby preventing force transmission from the first ring element via the clamping element to the second ring element. This prevents force transmission from the first ring element to the at least one clamping element or vice versa. In other words, it is advantageous if, upon sudden or rapid application of a high torque to the freewheel, the clamping elements move from the force transmission zone to the overload zone. This overload zone preferably prevents damage to the freewheel or clamping freewheel. If excessively high forces are applied to a freewheel, the clamping elements are pressed so abruptly and rapidly into the clamping profile or against the clamping ramps that they become worn out, which in turn can lead to total failure of the freewheel.

[0038] Furthermore, it is advantageous if the second section is designed as a force transmission area such that at least one clamping ramp and the clamping element clamp. Preferably, the clamping ramp and clamping element fulfill the clamping condition tanα < µ, thereby ensuring force transmission from the first ring element via the clamping element to the second ring element.

[0039] It is also advantageous if the first section is designed as an overload zone such that at least one clamping ramp and the clamping element slide. Advantageously, the clamping ramp and clamping element fulfill the sliding condition tanα≥µ, thereby preventing force transmission from the first ring element via the clamping element to the second ring element.

[0040] It is also preferred if the first and second ring elements are arranged concentrically to each other. Such an arrangement ensures low mechanical loss and a simple design, thus saving costs.

[0041] Preferably, the clamping element rests against at least one clamping ramp of the first ring element and against a surface of the second ring element. Thus, the clamping element directly connects the first and second ring elements, allowing forces to be transferred from the first ring element to the second or vice versa.

[0042] Preferably, the at least one clamping ramp is spatially oriented within the first ring element such that, along its path in the direction of rotation of the first ring element, in which a force can be transmitted from the first ring element to the second ring element, it increases the distance between the at least one clamping ramp of the first ring element and the surface of the second ring element, particularly continuously. Thus, forces can be transmitted from the first ring element to the second or vice versa.

[0043] The distance is preferably a line segment that extends through a center of rotation of the first and / or second ring element. Thus, the distance is understood to be the shortest distance between the first and second ring elements, or between the clamping ramp and the ring element.

[0044] Furthermore, it is advantageous if, when the freewheel arrangement is at rest, the surface of the first sub-area of ​​the at least one clamping ramp of the first ring element forms an angle greater than 30 degrees with a tangent at the contact point between the clamping element and the surface of the second ring element.

[0045] Preferably, when the freewheel arrangement is at rest, the surface of the second sub-area of ​​the at least one clamping ramp of the first ring element forms an angle between 6 and 9 degrees with a tangent at the contact point between the clamping element and the surface of the second ring element.

[0046] The aforementioned angle ranges enable sliding with tanα≥µ or clamping with tanα<µ. In other words, with an angle greater than 30 degrees, sliding between the clamping element and the clamping ramp or between the clamping element and the ring element can be easily achieved, whereas with an angle between 3 and 4.5 degrees, clamping between the clamping element and the clamping ramp or between the clamping element and the ring element can be ensured.

[0047] Furthermore, it is advantageous if the first ring element forms an outer ring and the second ring element forms an inner ring.

[0048] Alternatively, it is also possible for the first ring element to form an inner ring and the second ring element to form an outer ring.

[0049] The invention concept described above will now be expressed in other words.

[0050] This idea – in simplified terms – assumes that various types of freewheels are used as electric starter freewheels in two-wheelers. These include clamping freewheels and roller freewheels.

[0051] In most freewheels, the torque capacity is many times the nominal load. The reason for this oversizing is a worst-case scenario that can occur due to misfiring, where a large torque or force is rapidly introduced into the freewheel.

[0052] If the freewheel or the surrounding environment is insufficiently stable, the starter will fail completely and immediately.

[0053] Therefore, the task arises to equip current freewheel designs with an overload protection - torque limiting function.

[0054] Clamping roller freewheels are typically designed with a clamping ramp / ramp / clamping angle α1 of 3 to 4.5 degrees to achieve the highest possible switching reliability.

[0055] The well-known formula tanα<µ is preferably applied. During clamping, normal forces act on the outer ring / housing of the freewheel and widen it. The clamping rollers advantageously continue to move along the ramp geometry or the clamping ramp.

[0056] Preferably, a freewheel according to the invention has a further, significantly steeper ramp section in which, upon reaching a predetermined torque, the contact points between the clamping rollers or clamping elements and the outer ring or ring element shift, causing the clamping operation to become unbalanced. As a result, the clamping elements slip in the further ramp section, thereby limiting the torque / load to be transmitted.

[0057] In other words, ideally, the clamping ramps of a freewheel should be equipped with a second, significantly steeper section at a specific position. Ideally, this should result in the clamping condition tanα < µ no longer being met, and the clamping rollers or clamping elements on the clamping ramps or the ring element should begin to slip.

[0058] The invention is explained in more detail below with reference to exemplary embodiments and accompanying drawings. These schematically illustrate: Fig. 1 a sectional view of a clamping freewheel or a freewheel arrangement according to the invention; Fig. 2 an enlarged sectional view of a clamping element of the clamping freewheel according to the invention made of Fig. 1 in a first state; Fig. 3 an enlarged sectional view of a clamping element of the clamping freewheel according to the invention made of Fig. 1 in a second state; Fig. 4 a further enlarged sectional view of a clamping element of the clamping freewheel according to the invention Fig. 1 in the first state; and Fig. 5 an enlarged sectional view of the clamping freewheel according to the invention Fig. 1 without a clamping element.

[0059] In the following description, the same reference symbols are used for the same objects.

[0060] Fig. Figure 1 shows a sectional view of a clamping freewheel 1 according to the invention or of a freewheel arrangement 10 according to the invention.

[0061] The freewheel arrangement 10 has a clamping freewheel 1 with a first ring element 2 comprising several clamping ramps 3 and several clamping elements 4, each clamping ramp 3 serving to clamp one clamping element 4. The first ring element 2 is designed as an outer ring.

[0062] The first ring element 2 is pressed into an outer ring element 22 to form a positive and force-fit connection. In this way, the first ring element 2 can be designed with thin walls and used in various configurations within an outer ring element 22.

[0063] For a thin-walled design, the first ring element 2 can be made from a sheet of metal.

[0064] In the present case, the ring element 2 is designed with such thin walls that the hollow cylindrical ring element 2 has a wall thickness H outside the clamping ramp 3 or at the thickest position of the first ring element 2 in circumferential direction U, which comprises a fraction of the thickness of a clamping element 4.

[0065] According to the exemplary embodiment Fig. 1. The wall thickness H is less than 0.3 times the thickness of a clamping element 4.

[0066] Furthermore, the freewheel arrangement 10 includes a second ring element 11, which in the present embodiment is designed as an inner ring.

[0067] The first ring element 2 or the outer ring has - as already indicated - a clamping element 4 per clamping ramp 3, whereby the clamping element 4 rests on the respective clamping ramp 3 or the clamping element 4 contacts the clamping ramp 3.

[0068] Furthermore, each clamping element 4 shown rests on the associated clamping ramp 3 of the first ring element 2 and on a surface O of the second ring element 11. Thus, a force can be transmitted from the first ring element 2 to the second ring element 11 via the clamping element 4 or vice versa.

[0069] Here, each clamping ramp 3 has at least a first 5 and a second sub-section 6.

[0070] In operation of the clamping freewheel 1 or the freewheel arrangement 10, the first ring element, which rotates in the direction of rotation D, transmits a force to the second ring element 11 via the clamping elements 4.

[0071] Because when the first ring element 2 moves in the direction of rotation D, the clamping elements 4 move along the ramp geometry of the clamping ramps 3, which are tapered.

[0072] Within the second clamping area 6 of the clamping ramps 3, the clamping elements clamp between the clamping ramps 3 or the first ring element 2 and the second ring element 11.

[0073] However, if a high force or high torque is introduced into the clamping freewheel 1 within a short time interval, the clamping elements 4 move from the second sub-section 6 of the clamping ramp 3 towards the first sub-section 5.

[0074] This second section prevents damage to the entire clamping freewheel 1 or the entire clamping assembly 10. If excessively high forces are introduced into a freewheel, the clamping elements 4 are pressed so abruptly and rapidly into the clamping profile or against the clamping ramps 3 that they are damaged, which in turn can lead to a total failure of the freewheel.

[0075] Consequently, in the exemplary embodiment according Fig. 1 the first sub-area 5 is designed as an overload area such that each clamping element 4 moves relative to the respective clamping ramp 3, thereby preventing a force transmission from the first ring element 2 via the clamping element 4 to the second ring element 11.

[0076] In other words, the first sub-area 5 is designed as an overload area such that a clamping element 4 slides on the respective clamping ramp 3.

[0077] To better illustrate, the first sub-area 5 of each clamping ramp 3 and an associated clamping element 4 fulfill the slip condition tanα≥µ, whereby a force transmission from the first ring element 2 via the clamping element 4 to the second ring element 11 can be prevented or avoided.

[0078] In contrast, the second sub-area 6 is designed as a force transmission area such that a clamping element 4 clamps together with the respective clamping ramp 3. The second sub-area 6 of each clamping ramp 3 and an associated clamping element 4 fulfill the clamping condition tanα<µ, thereby ensuring or enabling force transmission from the first ring element 2 via the clamping element 4 to the second ring element 11.

[0079] Furthermore, it shows Fig. 1, that the first ring element 2 and the second ring element 11 are arranged concentrically to each other or concentrically to the center / center of rotation M of the freewheel arrangement 10.

[0080] In the present embodiment according to Fig. 1 The outer ring element 22 together with the first ring element 2 serves as the drive and the second ring element 11 as the output.

[0081] Here, as already mentioned above, the drive direction or direction of rotation D for the transmission of forces from the first ring element two or outer ring element 22 to the second ring element 11 is in Fig. 1 is marked.

[0082] The illustrated design of a freewheel arrangement 10 is according to Fig. 1 is only able to transmit forces from the drive or first ring element 2 to the output or second ring element 11 if the first ring element 2 has a higher or the same rotational speed as the second ring element 11. However, it is necessary that both ring elements 2 and 11 rotate in the direction of rotation D.

[0083] Between the first ring element 2 and the second ring element 11, in addition to the clamping elements 4 shown, a spring element 20 is shown for each clamping element 4. The spring elements 20 are compression springs that press the associated clamping element 4 against the direction of rotation D.

[0084] While a clamping element 4 rests against one side of a spring element 20, the spring element 20 is supported on the other side by a web 21. This web 21 is connected to the first ring element 2.

[0085] Each of the clamping ramps 3 is spatially oriented in the first ring element 2 such that, along its course in the direction of rotation D of the first ring element 2, it increases the distance X between the clamping ramp 3 of the first ring element 2 and the surface O of the second ring element 11. This increase is continuous, at least in the second sub-area 6 of the clamping ramp 3.

[0086] Finally, regarding Fig. 1. Note that in addition to the direction of rotation D, the circumferential direction U is also shown.

[0087] Fig. Figure 2 shows an enlarged sectional view of a clamping element 4 of the clamping freewheel 1 according to the invention. Fig. 1 in a first state.

[0088] In this case, the clamping freewheel 1 or the illustrated clamping roller freewheel 1 has the ring element 2 in the form of an outer ring, with various clamping ramps 3 each for clamping the clamping elements 4.

[0089] Furthermore, the clamping freewheel 1 - as already explained - includes a clamping element 4 per clamping ramp 3, which rests against the respective clamping ramp 3.

[0090] Each clamping ramp 3 has at least a first 5 and a second sub-area 6 and extends in the circumferential direction U.

[0091] The second sub-area 6 is designed as a force transmission area in such a way that a relative movement between clamping element 4 and ring element 2 can be prevented.

[0092] The first sub-area 5, on the other hand, is designed as an overload area in such a way that a relative movement between clamping element 4 and ring element 2 can be ensured, thereby preventing a force transmission from the first ring element 2 to the at least one clamping element 4.

[0093] When the ring element 2 rotates for force transmission, or when the ring element 2 rotates in the direction of rotation D, the first sub-section 5 follows the second sub-section 6. Thus, in the event of an overload, the clamping element 4 moves from the second sub-section 6 to the first sub-section 5 in order to interrupt the force transmission between the first sub-section 5, each clamping ramp 3 and the respective associated clamping element 4.

[0094] In the Fig. In the state shown in 2, the clamping elements 4 are located within the second sub-area 6 of the clamping ramps 3.

[0095] In this state, the second sub-area 6 prevents relative movement between each clamping element 4 and ring element 2.

[0096] This is achieved by ensuring that at the contact point A between clamping element 4 and clamping ramp 3, the tangent of the angle α formed between a force F to be transmitted and a normal N2 of the second sub-area 6 arranged on the contact point A is smaller than the coefficient of friction µ of the materials of the friction pair ring element 2 and clamping element 4.

[0097] The angle α in the second sub-section 6 is between 3 and 4.5 degrees. The normal N2 is perpendicular to the plane of the second sub-section 6 of the clamping ramp 3.

[0098] In simplified terms, the above situation means that each clamping ramp 3 and each associated clamping element 4 clamp or interlock with each other by fulfilling the clamping condition tanα<µ. Consequently, force transmission from the first ring element 2 via the clamping element 4 to the second ring element 11 is ensured.

[0099] With reference to Fig. Figure 3 shows that the clamping elements 4 are located within the first sub-area 5 of the clamping ramps 3 or are arranged there.

[0100] In the state after Fig. 3 The first sub-area 5 allows a relative movement between the clamping elements 4 and the ring element 2.

[0101] This is achieved by ensuring that at the contact point A between each clamping element 4 and each clamping ramp 3, the tangent of the angle α formed between a force F to be transmitted and a normal N1 of the first sub-area 5 arranged on the contact point A is greater than or equal to the coefficient of friction µ of the materials of the friction pair ring element 2 and clamping element 4.

[0102] Here, the angle α for the first sub-section 5 is greater than 15 degrees. The normal N1 is perpendicular to the plane of the first sub-section 5 of the clamping ramp 3.

[0103] According to the above facts Fig. In simplified terms, this means that the first sub-area 5 is designed as an overload zone such that each clamping ramp 3 and each associated clamping element 4 slips, slides against each other, or does not clamp. In this way, the slip condition tanα ≥ µ is fulfilled. Consequently, a force transmission from the first ring element 2 via the clamping element 4 to the second ring element 11 can be prevented.

[0104] Furthermore, it should be noted that when comparing the Fig. 2 and Fig. 3. Press the spring elements 20 of each clamping element 4 against the direction of rotation D. Here, the position is in Fig. 2 each spring element 20 on the clamping element 4 or on each clamping element 4, whereas in Fig. 3. Clamping element 4 and spring element 20 do not have contact with each other.

[0105] Fig. 4 is essentially identical to Fig. 2, but with additional reference symbols. Furthermore, it shows Fig. 4 the freewheel arrangement 10 or the clamping freewheel 1 at standstill or in a state in which no forces are transmitted.

[0106] When stationary, the surface of the first sub-area 5 of each clamping ramp 3 of the first ring element 2 forms an angle α1 with a tangent at the contact point B between clamping element 4 and the surface O of the second ring element 11. The angle α1 is greater than 30 degrees.

[0107] Furthermore, when the freewheel arrangement 10 is at rest, the surface of the second sub-area 6 of each clamping ramp 3 of the first ring element 2 forms an angle α2 with a tangent at the contact point B between clamping element 4 and the surface O of the second ring element 11. This angle is between 6 and 9 degrees.

[0108] Fig. Figure 5 shows an enlarged sectional view of the clamping freewheel 1 according to the invention. Fig. 1 without clamping elements 4.

[0109] Firstly, the angles α1 and α2 are shown again here, as previously defined with reference to Fig. 4 were described.

[0110] Furthermore, in Fig. 5 clearly shows that each clamping ramp 3 is spatially oriented in the first ring element 2 such that, along its course in the direction of rotation D of the first ring element 2, in which a force can be transferred from the first ring element 2 to the second ring element 11, it increases the distance X between each clamping ramp 3 of the first ring element 2 and the surface O of the second ring element 11.

[0111] Thus, the distance X2 is larger compared to the distance X1, as in Fig. 5 shown.

[0112] The distances X1 and X2 are line segments that extend through the center of rotation or center point M of the ring elements 2 and 11. Thus, these distances represent the shortest distance between the first ring element 2 and the second ring element 11, and between clamping ramp 3 and the surface O of ring element 11.

[0113] In the present example, according to Fig. 5 The distance between the first ring element 2 and the surface O of the second ring element 11 increases continuously in the direction of rotation D and within the area of ​​a clamping ramp 3. Reference symbol list 1 Clamping freewheel 2 first ring element 3 clamping ramp 4 clamping elements 5 first sub-area 6 second sub-area 10 Freewheel arrangement 11 second ring element 20 spring element 21 Bridge 22 Outer ring element A axis of rotation Direction of rotation F force M Center N1 Normal N2 Normal Surface U circumferential direction

Claims

[1] Freewheel (1), in particular roller freewheel, comprising: - a ring element (2), in particular an inner ring or an outer ring, with at least one clamping ramp (3) for clamping a clamping element (4), - one clamping element (4) per clamping ramp (3) which rests against at least one clamping ramp (3), - wherein the at least one clamping ramp (3) has at least a first (5) and a second sub-section (6), - wherein the second sub-area (6) is designed as a force transmission area in such a way that a relative movement between the clamping element (4) and the ring element (2) can be prevented, - wherein the first sub-area (5) is designed as an overload area such that a relative movement between clamping element (4) and ring element (2) can be ensured, thereby preventing a force transmission from the first ring element (2) to the at least one clamping element (4), - wherein the first sub-section (5) allows relative movement between clamping element (4) and ring element (2) by ensuring that at the contact point (A) between clamping element (4) and clamping ramp (3) the tangent of the angle (α) formed between a force (F) to be transmitted and a normal (N1) of the first sub-section (5) arranged on the contact point (A) is greater than or equal to the coefficient of friction (µ) of the materials of the friction pair ring element (2) and clamping element (4). [2] Clamping freewheel according to claim 1, - wherein, during a rotation of the ring element (2) for force transmission, the first sub-section (5) follows the second sub-section (6), so that preferably in the case of an overload the clamping element (4) moves from the second sub-section (6) towards the first sub-section (5) in order to interrupt the force transmission between the first sub-section (5) of the at least one clamping ramp (3) and the clamping element (4), - wherein preferably the at least one clamping ramp (3) extends in the circumferential direction (U). [3] Clamping freewheel according to claim 1 or 2, - wherein the second sub-section (6) prevents a relative movement between clamping element (4) and ring element (2), preferably by ensuring that at the contact point (A) between clamping element (4) and clamping ramp (3) the tangent of the angle (α) formed between a force (F) to be transmitted and a normal (N2) of the second sub-section (6) arranged on the contact point (A) is smaller than the coefficient of friction (µ) of the materials of the friction pair ring element (2) and clamping element (4). [4] Freewheel according to claim 3, - where the angle (α) for the first sub-area (5) is greater than 15 degrees, - wherein preferably the angle (α) in the second sub-area (6) is 3 to 4.5 degrees. [5] Clamping freewheel according to one of claims 1 to 4, - wherein the ring element (2) is made of a sheet metal, - wherein preferably the ring element (2) is designed to be thin-walled, - wherein preferably the ring element (2) is designed to be thin-walled such that the hollow cylindrical ring element (2) has a wall thickness (H) outside a clamping ramp (3) which comprises a fraction of the thickness of a clamping element (4), preferably less than 0.5 times the thickness of the clamping element (4), preferably less than 0.3 times the thickness of a clamping element (4). [6] Freewheel arrangement (10) comprising a clamping freewheel (1), in particular according to one of claims 1 to 4, with a first ring element (2), in particular in the configuration of an inner ring or an outer ring, and with at least one clamping ramp (3) for clamping a clamping element (4), and a second ring element (11), in particular an outer ring or an inner ring, - where the first ring element comprises (2): ◯ a clamping element (4) per clamping ramp (3) which rests against at least one clamping ramp (3), ◯ wherein the at least one clamping ramp (3) has at least a first (5) and a second sub-section (6), ◯ wherein the first sub-area (5) is designed as an overload area such that the clamping element (4) moves relative to the at least one clamping ramp (3), thereby preventing force transmission from the first ring element (2) via the clamping element (4) to the second ring element (11), and ◯ wherein the first sub-area (5) is designed as an overload area such that the at least one clamping ramp (3) and the clamping element (4) satisfy the slip condition tanα≥µ, thereby preventing force transmission from the first ring element (2) via the clamping element (4) to the second ring element (11). [7] Freewheel arrangement according to claim 6, - wherein the second sub-area (6) is designed as a force transmission area such that the at least one clamping ramp (3) and the clamping element (4) clamp, in particular fulfilling the clamping condition tanα<µ, thereby ensuring a force transmission from the first ring element (2) via the clamping element (4) to the second ring element (11). [8] Freewheel arrangement according to claim 7 or 8, - wherein the first ring element (2) and the second ring element (11) are arranged concentrically to each other, - wherein preferably the clamping element (4) rests on the at least one clamping ramp (3) of the first ring element (2) and on a surface (O) of the second ring element (11), - wherein preferably the at least one clamping ramp (3) is spatially oriented in the first ring element (2) such that it increases the distance (X) between the at least one clamping ramp (3) of the first ring element (2) and the surface (O) of the second ring element (11) along its course in the direction of rotation (D) of the first ring element (2), in which a force can be transmitted from the first ring element (2) to the second ring element (11), in particular continuously. [9] Freewheel arrangement according to one of claims 6 to 8, - wherein, when the freewheel arrangement (10) is at rest, the surface of the first sub-area (5) of the at least one clamping ramp (3) of the first ring element (2) forms an angle (α1) greater than 30 degrees with a tangent at the contact point (B) between the clamping element (4) and the surface (O) of the second ring element (11), - wherein preferably when the freewheel arrangement (10) is at rest, the surface of the second sub-area (6) of the at least one clamping ramp (3) of the first ring element (2) forms an angle (α2) between 6 and 9 degrees with a tangent at the contact point (B) between clamping element (4) and the surface (O) of the second ring element (11). [10] Freewheel arrangement according to one of claims 6 to 9, - wherein the first ring element (2) forms an outer ring and the second ring element (11) forms an inner ring, or - wherein the first ring element (2) forms an inner ring and the second ring element (11) forms an outer ring.

Images