Zero drag braking system

Abstract

A vehicle braking system that includes a brake disc, a first pad and a second pad arranged to clamp the brake disc, and further includes a guide slidably supporting a brake caliper. The braking system further includes an axially resilient retraction prong extending in a radial direction from a proximal portion engaged with the brake caliper to a distal portion frictionally engaged with the caliper guide, the distal portion of the retraction prong biased toward engagement with the caliper guide. The retraction prong is axially resilient and configured exert a retracting force on the brake caliper and the caliper guide such that the distal portion of the retraction prong is biased toward engagement with the caliper guide. The retracting force on the caliper guide and the brake caliper is configured to move both of the first pad and the second pad out of engagement with the brake disc.

Description

ZERO DRAG BRAKING SYSTEMCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The subject patent application claims priority to, and all the benefits of, Austrian Provisional Patent Application N° A 60133 / 2024, filed on July 10, 2024, and Austrian Provisional Patent Application N° A 60134 / 2024, filed on July 10, 2024, the entire contents of which are incorporated by reference herein.BACKGROUND

[0002] Electromechanical brakes (EMB) as disc brakes often have the pressing mechanism on one side (e.g. inboard) and then press the outboard pad (or friction lining) by pressing the inboard pad (or friction lining) and pulling the caliper inwards in a guide. When the brake is released, the pad pressed by the pressing mechanism can be lifted off the disc quite easily or the pad pressure can be removed (“or” is used here non-exclusively). The inboard pad can also be retracted with the pressing mechanism to provide support. For example, the inboard pad and pressing mechanism can be connected accordingly or follow the pressing mechanism through additional component(s), e.g. through spring action(s). Here, “effect” indicates that such an effect is described regardless of the presence or shape of components. A spring effect can therefore arise from a spring as a component or, for example, be present as a resilient property in completely different components or be generated by completely different means, such as magnetic force. A braking effect can therefore be, for example, the braking torque, the braking force, a deceleration, etc. Inboard pad lift-off is relatively easy with EMBs because there is a direct retracting movement through the actuator (and possibly additional components which also retract the pad), whereas with hydraulic brakes the piston retraction movement cannot easily be applied in a pulling manner, although the piston seals are sometimes said to have a retracting effect of the piston, however this retracting effect is weak when compared to forces internal to the hydraulic circuit. After a possible inboard pad lift-off, the caliper remains in one place where the outboard pad is still in contact with the disc. How tightly it remains in contact depends on the state of friction between the caliper and the guide. In the case of dirt or rust, etc., this can cause residual drag of over 2 Nm in a car brake, consuming drive energy and causing more abrasion or dust. There may also be residual contact force on the pressing side and / or also residual pressure. This residual drag can also be noticeable, e.g. how well a car rolls out. A so-called non-linear EMB is recommended here, which has a gear ratio thatchanges over the actuation stroke, because with these there is rapid pad / friction lining movement in the range of low contact force, which slows down in the range of high contact force. If a brake is deliberately operated with an air gap, it is of course advantageous if this gap can be passed through quickly and contact force can be built up quickly. These disc brakes usually have brake pads 6,7 on both sides of a brake disc, but all of the following statements also apply exactly or analogously to any number of brake pads, from one to many (e.g. in multi-disc or multi-disc brakes) and also to other designs such as fixed caliper brakes or drum brakes.SUMMARY

[0003] In one aspect, a braking system includes a brake disc or friction surface coupled to a rotating machine. The braking system includes a first friction lining and a second friction lining arranged for clamping engagement with the brake disc. The braking system further includes a guide and a brake caliper. The guide may or may not be directly coupled to the vehicle. The brake caliper is slidably supported by the guide and operably engaged with each of the first friction lining and the second friction lining, wherein the brake caliper includes a pressing mechanism operable to urge the first friction lining into engagement with the friction surface. The braking system further includes a retraction prong extending in a radial direction from a proximal portion engaged with the brake caliper to a distal portion frictionally engaged with the caliper guide. The retraction prong is axially resilient and configured to exert a retracting force on the brake caliper and the guide opposing the pressing mechanism. The distal portion of the retraction prong is biased toward engagement with the guide. The retracting force on the guide and the brake caliper is configured to move both of the first friction lining and the second friction lining out of engagement with the brake disc.

[0004] In another aspect, a method of operating a braking system including a brake disc, a first friction lining and a second friction lining arranged for clamping engagement with the brake disc, a guide, a brake caliper slidably supported by the guide and operably engaged with each of the first friction lining and the second friction lining, the brake caliper including a pressing mechanism actuatable to urge the first friction lining into engagement with the brake disc, and an axially resilient retraction prong extending from a proximal portion engaged with the brake caliper to a distal portion frictionally engaged with the caliper guide, the distal portion of the retraction prong biased toward engagement with the guide is disclosed. The method includes the steps of actuating the pressing mechanism to urge the first friction lining into engagement with the brake disc orfriction surface, applying a clamping force to the brake disc between the first friction lining and the second friction lining, and moving the caliper relative to the guide in response to applying the clamping force. The method further includes the step of in response to moving the caliper relative to the caliper guide, displacing the distal portion of the retraction prong to store a retracting force. The method further includes the step of actuating the pressing mechanism to release the clamping force on the brake disc. The method further includes the step of in response to releasing the clamping force on the brake disc, moving the first friction lining and the second friction lining out of engagement with the brake disc using the stored retracting force.

[0005] Any of the above aspects can be combined in full or in part. Any features of the above aspects can be combined in full or in part. Any of the above implementations for any aspect can be combined with any other aspect. Any of the above implementations can be combined with any other implementation whether for the same aspect or a different aspect.BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Advantages of the present disclosure will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings.

[0007] Fig. 1 shows a first exemplary braking system with a brake disc, a caliper guide, a floating caliper having a piston, and an inboard brake pad 6 and outboard brake pad 7.

[0008] Fig. 2 shows the effects of wear of the pads or changes in the brake. Specifically, a stored position of the floating caliper is moved to a different stored position due to contact between the floating caliper and a retraction prong.

[0009] Fig. 3A shows a first step in a pad-lifting-process in which the braking system is in a braking state and a stored position with sufficient clearance for a pushing out motion relative to the caliper guide.

[0010] Fig. 3B shows the braking system of Fig. 3A in a released brake state and when clamping has ceased. The inner pad is not pulled away from the disc but free to be pushed away when friction can be overcome.

[0011] Fig. 3C shows the braking system in a full released position by a command to the brake or by a decision in the brake (e.g. in the brake control) and / or that the actuator was brought (e.g. by assertion in the brake control) to the condition that the lifting force is high enough to lift the pad(s) from the disc.

[0012] Fig. 4A shows an exemplary braking system with two implementations of a pad lifting mechanism. A first implementation of the pad lifting mechanism is shown having a retraction prong arranged between a brake caliper and a caliper guide on the upper half of Fig. 4 A. A second implementation of the pad lifting mechanism is shown having a retraction prong arranged between the brake caliper and the caliper guide on the lower half of Fig. 4A.

[0013] Fig. 4B shows an alternative implementation of a pad lifting mechanism utilizing a contrasting principle of operation and having a fixed pivot preventing radial movement of the retraction prong.

[0014] Fig. 5 shows a drum brake system with an expander configured to generate a pressing force to apply the brakes and springs that can push the brake shoes with brake linings away from a brake drum.

[0015] Fig. 6 shows another implementation of a drum brake system where the expander is configured for a floating motion like e.g. floating simplex or some servo-drum brakes such as bidirectional.

[0016] Fig. 7 shows another implementation of a drum brake system with a shoe with a lining lifting mechanism.DETAILED DESCRIPTION

[0017] In the following explanations it is assumed that there is an analog or digital brake control or regulation which, for example, adjusts the brake actuator according to a braking request, for example positions it, i.e. sets a motor angle. This makes definitions important: It is assumed here that the operator (or automatic system such as a vehicle’s automatic emergency braking system, etc.) specifies a target braking effect and that a time-related actual braking effect is created. In order to define the mode of operation, a complete distinction must be made here as to whether the brake is being applied or released (which would be an actual process) or whether there is a command for a certain braking effect or no braking at all (which would be the target states). One will therefore define what a non-braking command is (e.g. a target braking effect = 0) and what something else (e.g. target braking effect > 0, brake command) is a more or less strong desired braking, which can range from practically imperceptible to full application. The brake should adjust the actual braking effect with a time delay and a certain degree of accuracy, although this could also be impossible if in a vehicle the wheels are unable to provide this, for example due to poor road grip. The brakes presented here will preferably make a transition between a no-brakingcommand and a braking command (or if such brakes are used), switching from lifted brake pads to applied brake pads and vice versa with a time delay. Due to finite accuracy, it cannot be guaranteed how much braking effect will or will not be achieved with the slightest braking command. In any case, the no-braking command is preferably used here as the command to lift the pads. Automatic systems could also use this and, for example, give a short braking command in wet conditions to briefly bring the pads into slight contact, for example to wipe off moisture, etc. Of course, it could also be operated differently, for example so that the transition from no-braking to braking appears to disappear and, for example, as the braking command increases, a transition from lifted pads to applied pads occurs more and more, with some kind of increasing braking effect. Such apparent circumventions of the command transition from no braking to braking are of course interpreted here in such a way that it can be assigned in whatever way whether braking should or should not occur. Even if there may not appear to be a clear distinction between braking and no braking in specific cases, it is assumed here that this distinction is somehow possible even in such cases. It is therefore assumed that the brake control can determine somehow whether braking or no braking is required or can behave accordingly. Other formulations or commands also use the pad lifts presented here, of course. If, for example, only braking commands are possible, but no braking command, but instead a zero-drag command, lift-off command, drive command to, for example, a vehicle drive motor, etc. is used, then this naturally also falls under what is presented here. In this case, a no braking command can therefore be viewed as generally as possible and not just in its wording. It should be appreciated that the braking system 100 described herein may be implemented on applications other than a vehicle. For example, the braking system 100 may be used in machinery systems such as a wind turbine to reduce drag and increase efficiency.

[0018] There are known approaches using primarily springs to push the pads away from the brake disc 2. However, springs can generate a certain force, but cannot guarantee a small finite travel depending on the load (under different friction conditions of the floating caliper in the guide). The small air gap (e.g. 0.2 mm between each friction lining and friction surface) must be introduced between the disc surface and the pad surface, and both are hardly accessible because the disc rotates and the pad wears. In addition, the floating caliper 4 takes on different positions, e.g. depending on pad wear, so that in this regard too, no longer valid starting point for a lifting movement is possible. As will be discussed below, a system to facilitate lifting the pads from the brake disc surface with a defined travel, especially the outboard pad.

[0019] In principle, these designs can also be applied to drum brakes (preferably servo drum brakes). The two brake shoe ends, which are movable to transfer the braking force from the primary shoe to the secondary shoe, can be lifted from the brake drum in the same or similar way as disc brake pads are lifted from the brake disc in this design. Any other features, such as lifting when there is no braking command, can also be applied.

[0020] In Fig. 1, a first implementation of a braking system 100, which includes a brake disc 2, a caliper guide 5 coupled to a vehicle, a brake caliper 4 slidably supported by the caliper guide 5. The brake caliper 4 may be a floating caliper. The braking system 100 further includes a first friction lining, shown here as an inboard brake pad 6, and a second friction lining, shown here as an outboard brake pad 7. The floating caliper 4 is operably engaged with each of the inboard brake pad 6 and the outboard brake pad 7. Additionally, the floating caliper 4 includes a pressing mechanism or piston 8 operable to urge the inboard brake pad 6 into engagement with the brake disc 2. In some implementations the braking system 100 may include a wear adjustment mechanism. In Fig. 1, the caliper 4 is shown in a stored position 9 that may be maintained by a pressing force by a prong spring 12. The stored position 9 acts as an anchor point for the force applied by the axial spring 11 on the guide 5.

[0021] The braking system 100 of Fig. 1 further includes a retraction mechanism configured to generate an air gap 150 between the pads 6, 7 and the brake disc 2 at the end of a braking event. A first implementation of the retraction mechanism includes a retraction prong 18 extending in a radial direction (i.e., generally perpendicular to the axis of rotation of the brake disc) from a proximal portion 18 A engaged with the brake caliper 4 to a distal portion 18B frictionally engaged with the caliper guide 5. The distal position 18B of the retraction prong 18 is biased toward engagement with the caliper guide 5. The retraction prong 18 is axially resilient and configured to exert a retracting force on the brake caliper 4 and the caliper guide 5 opposing the piston 8. The retracting force on the caliper guide 5 and the brake caliper 4 is configured to move the outboard brake pad 7 out of engagement with the brake disc 2 to create an air gap 150 while the inboard brake pad 6 is moved out of engagement with the brake disc 2 by the pressing mechanism 8.

[0022] For lifting, including the outboard lining 7, the braking system 100 shown in Fig. 1 includes the brake pads 6, 7 having a lot of lining material and in Fig. 2, the brake pads 6, 7 are shown with less lining material, whereby the contact pressure with wear adjuster has compensated for the wear and the floating caliper 4 takes up a different position. Said differently, in Fig. 1, thebrake pads 6, 7 are in an unworn condition with a majority of the lining material remaining, whereas Fig. 2 shows the brake pads 6, 7 in a worn condition with decreased lining material. All of the following considerations can be applied analogously to a different caliper brake, e.g. fixed caliper brake, or even to multi-disc brakes. Since an EMB preferably has the contact piston or pressing mechanism 8 on one side only, these designs are of course particularly interesting for floating caliper brakes (or multi-disc brakes). The wear adjuster can be located at any suitable point; in this case, the resulting movement sequences may have to be adapted, but the principle shown here remains. The pressing mechanism 8 may be implemented in using a variety of different mechanisms, for example using energies other than electrical such as hydraulic. In all of the designs presented (the operating principle can be the same but designed differently, preferably on both sides of the floating caliper), a position storage 9 (e.g. static friction with, for example, a spring effect on, for example, the floating caliper guide, ratchet effect, clamping effect, magnetic attraction, etc. on, for example, a pin or without an additional part with existing ones) is important. In Fig. 1, the brake caliper 4 is axially spaced from the caliper guide 5 by a distance 190. Fig. 2 shows a different stored position 10, i.e. the position storage 9 was applied to a part of the floating caliper due to wear with force from the clamping movement and would move further and further to the left if it came into contact with a part of the floating caliper with further wear and clamping movement. Said differently, the brake caliper 4 is axially spaced from the caliper guide 5 by a distance 192, which is less than the distance 190. This different stored position 10, which is created in each case, serves as the anchor point for a pushing-out effect (e.g. by an axial spring 11), which pushes the floating caliper 4 out again when the clamping movement ceases and creates an air gap 150. Here, the retraction prong 18 is slidable relative to the brake caliper in a radial direction. As mentioned above, the retraction prong 18 is biased toward engagement with the caliper guide 5. To this end, the braking system 100 further includes a prong spring 12 arranged between the brake caliper 4 and the proximal portion 18B of the retraction prong 18. The prong spring 12 biases the retraction prong 18 in a radial direction toward engagement with the caliper guide 5.

[0023] The implementation of the braking system 100 shown in Figs. 1 and 2 further includes an axial spring 11 arranged between the retraction prong 18 and the brake caliper 4. The axial spring 11 creates a pushing out force to urge the brake caliper 4 outward in an axial direction (i.e., generally parallel to the axis of rotation of the brake disc 2). Friction between the retraction prong18 and the caliper guide 5 causes the brake caliper 4 to move relative to the caliper guide 5 rather than moving the retraction prong 18 relative to the caliper guide 5.

[0024] In the implementation described here, the pushing-out movement of the brake caliper 4 to create the air gap 150 on this brake pad 6, 7 or the pad lifting movement of the directly pressed pad 6 is carried out after the braking is no longer applied, i.e. after application or release, when the clamping force is no longer applied. Since, due to finite accuracies, transition areas arise in reality, i.e. minimal lift-off force and thus possibly minimal lift-off movement can begin before the clamping force reaches zero or even slightly afterwards, it is always expressed or understood here, out of consideration for reality, that in reality the lift-off force or lift-off movement (a small force could cause no movement or could already cause some movement) does not begin exactly when the braking request is no longer requested (no more contact force is required). This also means that if the pad lift-off force is greater than the application force, a lift-off movement can begin as soon as the static friction between floating caliper 4 and the guide 5 when the pressed-on pad is retracted can be overcome. Theoretically, depending on the exact brake design, this could all change suddenly. However, after the braking request has disappeared, the majority of the lift-off movement only begins until the responsible actuator has reached its final state of non-braking. Other influencing factors could also be found, such as the fact that in reality brake discs do not have a perfectly uniform thickness across the circumference and no running is completely free of axial error ("figure eight"). In order to avoid having to describe this exact sequence every time, and because most or all of the lift-off movement is carried out from the final non-braking state, the following summary shows that the pad lift-off in the brakes presented here occurs due to nonbraking, which includes the exact sequence and possible other influences. Of course, at least one lifting movement can also be more or less independent of the brake actuation movement, e.g. carried out by a separate actuator or e.g. by the brake actuation actuator independently of normal braking, e.g. the lifting takes place in a certain, designated area, which can also be in the opposite direction of rotation to the pad contact pressure. With such actuators, it is also possible to completely differentiate whether braking or lifting is taking place, and the extent of the lifting can also be controlled. In general, the extent of the at least one lifting movement can be changed if necessary, by positioning it more or less in a lifting area, however arranged. If several lifting movements are introduced (e.g. one on each floating caliper guide 5), these should (“should” is understood here as the desired goal) be at least sufficiently symmetrical (e.g. with regard to forceor travel, etc.) that deviations do not lead to adverse effects such as the floating caliper jamming in the guide, stiffness, wear, etc.

[0025] Fig. 2 shows the effects of wear of the pads 6, 7 or changes in the brake system 100. Specifically, a stored position 190 of the floating caliper is moved to a different stored position 192 due to contact between the floating caliper and a retraction prong. After this movement, a stored position 9 and a different stored position 10 is the same as long as no new pad or lining wear has occured. From this stored positions (where 9 and 10 is now, after moving, of the same meaning) a pushing out effect of the axial spring 11 (e.g. a spring) can push the floating caliper out, relative to the stored positions 9,10. A stroke limiter 14 can define the magnitude of the pushing out motion and a clearance for more pushing out motion 13 can allow space for this motion. Retraction aids 16 can help that the pads follow the motion and are not stuck at position.

[0026] The extent of the outward movement can be limited, for example, with a stroke limiter 14. If, for example, average braking is g / 3 to g / 4, the stroke limiter 14 can achieve a sufficient outward movement; this can therefore easily lead to a usable lift for normal braking. This can also make additional freedom for greater outward movement 13 advantageous: this can give the floating caliper 4 so much freedom that it can move itself (e.g. due to vibrations, disc movements, cornering, etc.) into a normal position, as would be possible with a normal floating caliper, for example. Without this additional freedom for greater outward movement 13, the stored position can otherwise cause at least one pad to drag, reducing the advantages of this principle with pads lifted on both sides and potentially causing more residual drag than with normal floating caliper brakes. For better recognition, the designations in Fig. 1 and 2 are often shown on only one side (top, bottom, Fig. 1, 2). Of course, a symmetrical structure is advantageous and the parts not designated here would have the corresponding function.

[0027] The design for the displaceability of the position storage mechanism 9 can be designed as follows, for example: The position storage mechanism 9 should remain in position so well that it is not displaced when the floating caliper is pushed out. However, if the position storage mechanism 9 is to be moved to another stored position 10, then it should draw as little force as possible from the application movement. A brake with, for example, a 40 kN nominal clamping force can have, for example, a 4 kNm nominal braking torque and should have a residual drag torque of well under 20 Nm, even in a very poor case requiring repair, which could result from the outboard lining clamping of the floating caliper. The residual drag torque would then be 1 / 200 ofthe nominal braking torque and the contact pressure causing it, i.e. clamping the floating caliper, would be 200 N, for example. Normal braking occurs at g / 3 to g / 4, so braking at 0.05 g is particularly weak, which in the example would correspond to 200 Nm or 2 kN. A maximum of 500 N for moving to another stored position 10 per one of two position memories may be allowed. Removing a total of 1000 N from the clamping force would change the braking torque minimally with this very weak braking, but that would be in a braking range that is almost always passed through for more braking. The coefficient of friction that holds the position memory 9 in place could be 0.2, for example, in which a possible contact pressure of 2.5 kN would generate 500 N of frictional force. If both position storage mechanisms together require 1 kN of displacement force, and can therefore also support 1 kN against displacement, it is very easy to push out even quite stiff floating calipers, which require, for example, 200 N. In this example, the friction force for position storage 9 (and thus the force that must be applied by clamping and sliding) can be significantly reduced in order to maintain the pushing-out function for pad lift-off. If spring(s) are present for the pushing-out effect of the axial spring 11 , they naturally need or should apply less force (this can also be related to their respective length), otherwise they could move position storage 9 instead of pushing out the floating caliper. These principles may be applied in any direction, for example, setting a target for a desired pushing-out force and checking as above whether this can be achieved (e.g. with regard to clamping force). The pushing-out effect of the axial spring 11 determined in this way now determines the maximum clamping effect between the floating caliper 4 and the floating caliper guide 5 for pushing out, or weaker pushing-out effects can of course also be used, with correspondingly less possibility of pushing out the floating caliper. The forces must of course be calculated correctly with regard to the number of parts involved and the sum of the forces. These design criteria are of course important for the functionality of this invention, because otherwise, for example, only the position storage 9 would move in a sliding manner, without any meaningful pushing out of the floating caliper. The same interaction of the influencing factors (e.g. possible contact force of the position storage, possible friction or other closure of the position storage, clamping force at which effect is to be generated, size of the pushing-out movement, etc.) can of course be achieved using other calculations, which are always based on the same principles. Of course, other influences can also be taken into account, such as tolerances, changes (e.g. temperature-related, etc.). Of course, a design as advantageous as shown could also be achieved in other ways, such as by chance, trial and error, or by forgetting how thedesign was carried out, etc. However, this would still correctly apply the basic principles described, and the design would therefore again be based on the one shown. The components can, of course, also look or be attached differently, or additional components can be added, or combined in such a way that fewer parts are required for the same or a similar effect; however, this does not change the basic principle. The designs shown above can, of course, be applied analogously to all the brakes shown here (including the following ones).

[0028] Figs. 3A-3C shows the sequence according to the above description. In Fig. 3A, the retraction prong 18 has assumed a different stored position 10 by actuation of the pressing mechanism or piston 8, thereby urging the inboard brake pad 6 toward the brake disc 2, and by reaction, urging the outboard pad 7 (and also consequently compressing spring 11) toward the brake disc 2. A contact pressure stroke has been introduced. In Fig. 3B, the brake application is ended (i.e., the user has released the brake pedal and the piston 8 is no longer exerting force on the brake disc), but the pads 6, 7 have not yet been lifted away from the brake disc 2. In Fig. 3C, a non-braking state is reached and it can be seen that the stroke limiter 14 can still move from relative to its position in Fig. 3B in order to make the full limited stroke in Fig. 3C and push the outboard pad 7 away from the brake disc 2. It can be seen that the design described above is important, because otherwise the position storage device 9 would only slide relative to the caliper guide 5 without lifting movement of the brake pads 6, 7, or the application force could be adversely affected (e.g. adversely reduced). It can also be seen that the stroke limiter 14 and various positions of the other stored position (depending on the size of the application movement, i.e. the braking effect) mean that only certain cases (e.g. normal braking) lead to good lift-off of the outboard lining, whereby a larger planned air gap 150 allows a larger area of good lift-off. It can also be seen that without freedom for greater outward movement 13 the brake can have significantly worse residual drag than conventional brakes, since in this case the stored position can be a hindrance. This freedom can therefore be important in order to avoid worse-than-usual cases. This freedom for greater outward movement 13 does not necessarily have to be recognizable as a component or design; it is sufficient if the design is such that this freedom arises. It can therefore also be implemented by omitting designs that would otherwise restrict this freedom. Retraction aids 16 can also be advantageous for all of the devices shown here, helping to actually lift the pads during the lifting movements, so that they do not remain in an unfavorable location (e.g., dragging). These can be, for example, fastenings, resilient fastenings, springs, etc. This design does not require (anddoes not have) any play or disruptive play to create the usual small air gaps, because spring tension is available for displacement. Designs with play could easily make targeted lifting impossible or difficult with the small air gaps. Retraction aids 16 can pull the pad(s) away from the disc 2 and the stroke limiter 14 has produced a defined lifting motion that was possible due to consuming the space in the clearance for more pushing out motion 13.

[0029] According to the above explanations, one therefore obtains a very simple effect which in many cases lifts off well. An improvement over the above explanations (according to Figs. 1 to 3) would be to make the stroke limiter 14 adjustable, i.e. to apply more or less stroke limitation depending on the size of the application movement. Because with the correct stroke, the correct pushing out movement of the floating caliper can be achieved over many or all braking forces. This can be implemented in many ways, e.g. by means of a movable wedge which limits different strokes in the stroke limiter 14 (the stroke limiters) depending on a brake actuator position (or a position resulting from it). There are many ways, even simple ways, of deriving at least one movement from the brake actuator position which specifies a stroke size.

[0030] Here, a particularly simple, effective solution is presented with regard to Fig. 4: In the suggestions from Figs. 1 to 3C, pad lift corresponds to how much application movement was introduced (by the brake effect setting) and was therefore only possible with suitable braking, because the position of the other stored position depends on the application movement. It is proposed that, by introducing a compensation movement, the dependence of the other stored position on the size of the application movement is avoided by ensuring that the other stored position 10 remains constant, regardless of the brake effect setting. This means that pad lift can also be carried out with practically constant accuracy, which means that no (e.g. mathematical) perfection is required, but the accuracy can be such that, with different brake effect settings, satisfactory pad lift or pad lift that can be recognized by the air gap is still carried out. This can also be achieved here, as the linear pad pressing movement, the application movement, and the displacement movement between the floating caliper 4 and the guide 5 are all linearly proportionally related, allowing the brake system 100 to generate a compensating movement from one of these movements by simply translating the movement (e.g., using a lever). With regard to Fig. 4A, this means that the position of the position storage 9 (apart from unavoidable small, non- disruptive errors) only depends on pad wear if the proportion of the floating caliper movement 19 (as explained above, another movement could be used that has the same or similarly good effect)and the transmission ratio of the retraction prong 18 are selected such that the application movement no longer has any (disruptive) influence on the position storage 9, i.e., it is compensated. This means that while the brake 100 is being applied or released, the position of the position storage 9 no longer changes if the introduced compensating movement compensates for the floating caliper displacement in the floating caliper guide 5 as precisely as possible or compensates for the pad lifting precisely enough. If the retraction prong 18 has, for example, a transmission ratio of 2 to 1 (e.g. the proportion of the floating caliper movement 19 is twice as large as the displacement movement of the floating caliper 4 relative to the guide 5) and the brake 100 behaves the same inside and outside with regard to air gap 150 and deformations, in this example the stroke of the piston 8 can be fed directly as a proportion of the floating caliper movement 19 in order to achieve a constant position of the position storage 9 during application and release, regardless of the stroke. If the brake 100 now makes a retraction movement of the piston 8 after being applied or released (i.e. when the outboard pad is to be pushed out), in this example exactly half of this retraction movement is used as the pushing out movement of the floating caliper due to the leverage of the retraction prong 18 and both air gaps 150 are in this case the same size. Since the guides of the retraction prong 18 are sufficiently free of play to have little to no play, this small pushing out movement can also be implemented with sufficient accuracy. If wear occurs, the position storage 9 will assume a different stored position 10 and this compensated movement sequence will keep it in the same place again regardless of the application stroke until further wear occurs. In reality, of course, all of this will occur with finite accuracy.

[0031] This portion of the floating caliper movement 19, which is converted into the compensation movement with the transmission of the retraction prong 18, can in principle originate from any stage of the brake actuator transmission, i.e. also from the pad pressing movement, or it could also be generated in another way, e.g. with a separate actuator, whereby it is of course advantageous if the proportionality of the movements is sufficient for the shown sequence to function well and precisely. Of course, a portion other than half can also have the advantage of achieving a reasonably equal air gap 150 on both sides of the brake disc 2. The desired air gap 150 can also be related to conditions, e.g. temperature(s). The transmission of the retraction prong 18 can be specified, for example, with the geometry of the lengths involved. However, an adaptable drive with definable transmission behavior can also be advantageous, e.g. with a cam that acts directly or indirectly on at least one retraction prong 18. Advantageous variants of themany possible ones are shown in Fig. 4A, whereby it is advantageous to use symmetrical solutions and not different ones on both sides. Various implementations are only drawn to illustrate different possibilities. The position storage 9 can, for example, be a position held by friction, a ratchet effect, a clamping effect, a controlled or uncontrolled approach to the position, etc. For this purpose, for example in Fig. 4A the braking system 100 may further include one or more stanchions 17. In particular, the caliper 4 may include a caliper stanchion 17A slidably engaged with the proximal portionl8A of the retraction prong 18. The caliper stanchion 17A is arranged to limit axial movement of the retraction prong 18 relative to the brake caliper 4. More specifically, the caliper stanchion 17A may be implemented at a pair of stanchion posts each coupled to the caliper 4 with the retraction prong arranged therebetween. Additionally, the caliper guide 5 may include a guide stanchion 17B. The guide stanchion 17B is slidably engaged with the distal portion 18B of the retraction prong 18 and is arranged to limit axial movement of the retraction prong 18 relative to the caliper guide 5. Similar to the caliper stanchion 17A, the guide stanchion 17B may be implemented at a pair of stanchion posts each coupled to the caliper guide 5 with the retraction prong arranged therebetween.

[0032] Since the floating caliper 4 and caliper guide 5 move relative to one another, it is fundamentally irrelevant whether the (e.g. friction-based) position storage 9 stores the position with respect to the caliper guide 5 or with respect to the floating caliper 4. In contrast to Fig. 4A, the position storage device 9 could also store the position (e.g. through friction) with respect to the floating caliper 4, which of course results in some logically resulting (and therefore not mentioned) changes. The floating caliper guide 5 can also be interpreted as "stationary" (because the floating caliper moves in this respect) and can be connected, for example, to the wheel bearing component. It is important for the function that there must be no connection on either side of the retraction prong 18 with either the floating caliper 4 or the caliper guide 5. A design with a connection instead of displacement would only theoretically be possible if no lining wear were permitted and thus no other stored positions would arise due to pad lining wear. Such a solution would either have to be manufactured very precisely during production due to the small air gaps or be precisely adjusted. Instead of at least one retraction prong 18, which could also be called a coupling part, being connected to the movable (e.g. floating caliper 4) and the stationary (e.g. floating caliper guide 5) brake part, the solution shown here only works with planned pad wear if this connection does not exist and, on the contrary, at least one point per such mechanism is movable, i.e. has the oppositeproperty of being "connected" and can be moved. A mechanical forced coupling that connects the movable and stationary brake parts with each other must also not be present here, because in contrast to a forcibly fixed position, a different stored position 10 must be able to be assumed due to pad wear. A forced coupling would not allow a displacement of a position storage 9 caused by application, because there would be a constraint instead of a displacement option. The method presented here (as or similar to Fig. 4A) pushes the floating caliper out by not braking (not during at least part of the actuation or release movement). The inboard pad 6 is also lifted off of the brake disc 2 by not braking. During the actuation movement (applying the brake) or at least part of it, the other stored position may only be brought about, and no movable part (floating caliper) is displaced at all due to a mechanical forced coupling (which does not exist here either) relative to the stationary part (floating caliper guide). This is because the displacement movement of the floating caliper 4 to the floating caliper guide 5 during actuation occurs here without forced coupling, as with any other floating caliper brake, by the inboard pad 6 being pressed against the brake disc 2, thereby pulling the outboard pad 7 with the floating caliper 5 towards the brake disc 2, and these two movements apply the pads 6, 7. The compensating movement ensures that no additional forces are introduced between the floating caliper 4 and the guide 5. Although not present and undesired, such an additional force would only shift the position storage 9 and therefore could not be built up particularly effectively here. It is therefore also impossible for a coupling part (here called the retraction prong) to drive during at least part of the actuation of a caliper brake, so that the movable brake part is shifted relative to the stationary one due to a forced coupling (which is also not present here), because here the displacement force for the relative displacement comes from the application process, as with practically all floating caliper brakes, and not from a coupling part. On the contrary, only when a shift to another stored position 10 is necessary due to pad wear would the displacement force of the position storage part be taken from the application movement, thus leaving even slightly less force to move the floating caliper 4.

[0033] In typical braking systems, a movable brake part (floating caliper) is displaced relative to the stationary part when actuated, or a pivot point and the brake caliper are at least partially displaced when released, however this does not also cause the brake pads to lift off of the brake disc 2. Movement that occurs between the floating caliper and the floating caliper guide when actuated or released is common with typical floating caliper brakes and in any case does not need or have any additional parts such as coupling parts, pivot points, etc., and no parts in the casepresented serve to move the floating caliper in its guide, because that is what the application force does here.

[0034] It is advantageous to use a no-braking command to a brake control or regulation, which can, for example, be present (e.g. as a lift command, as a braking effect of, for example, 0 in contrast to, for example, braking commands with a braking effect of, for example, > 0) or can or could be obtained by, for example, correspondingly low braking effects leading to lift-off. The solution presented here uses the no-braking command for pad lift-off. From the point of view of brake control or regulation, this solution with the no-braking command is also particularly advantageous and clear if it is very clear from the command to the control (or obtained in the control) whether the air gap state with the pads lifted should be set or whether a certain braking action with the pads in contact should already be carried out. Such an application of the no-braking command causes the brake to either adjust at least one air gap or apply at least one pad, also with a time response, because, for example, lift-off after braking can also occur more slowly than, for example, the application of the pads, which can also be associated with urgent braking. However, there can also be a (e.g. smooth) transition, particularly in the application range, to avoid, for example, the brake suddenly starting with too high a braking effect due to a tolerance in the setting accuracy or, for example, not perceptibly executing very small braking effect commands because, for example, the exact application has not yet been achieved due to inaccuracy. In this way, a smooth application of the brake can be achieved, especially in the application range, which can be well dosed, but due to accuracy reasons does not correspond to a small braking effect that can be precisely assigned when no-braking changes to braking. Due to accuracy reasons, the small braking effect could only begin with a higher braking command, or there could already be slightly too much braking effect with the smallest command. This behavior is generally configured so that the driver has a well-controlled feeling even with (possibly very) slight braking. The application and release process is preferably designed so that it is as unnoticeable as possible (e.g. smooth, without sudden onset or interruption of the braking effect, etc.). To this end, for example, the lifting movement or the lowering of the previously applied slight brake can be carried out slowly (possibly if, for example, complete termination is not time-critical) or the application process can also proceed accordingly (e.g. slowly) until slight braking is achieved. The way the braking command is carried out can also influence the application or release process (e.g. speed), so that, for example, in the case of rapid or strong braking, this process is changed in favor of one that isas fast as possible. Such processes can take place or be supported in the brake control or regulation system if necessary. In particular, the lift-off process can be designed in such a way that no stresses or disruptive effects (e.g. noises) occur in the area of complete lift-off, e.g. due to contact with stops, etc. A braking request can also be accepted during the lift-off process and application or actuation can begin. The lift-off can also be changed by influences, e.g. the pads are already applied when the accelerator is released (or e.g. an impending emergency braking situation, etc.), they remain applied for a certain time after braking (if, for example, further braking is expected), they are sometimes applied, for example in the rain, or they are occasionally applied or (possibly lightly) applied to prevent deterioration over time. These processes can originate from the brake control or regulation or come from outside. They can adapt to influencing factors.

[0035] The correct air gap 150 is preferably set, e.g. with a wear adjuster, whereby the correct adjustment can also be made with reference to influences such as temperature, thermal expansion, etc. (under certain circumstances). For the brakes in question, a signal can also be obtained, preferably when braking is infrequent, as to whether and how hard the brakes are already being braked. This can be obtained in any way, e.g. with something conductive in the brake pad that signals contact with the disc or drum, by means of drag force detection (e.g. spring-loaded switch that switches at a certain point) or drag force measurement, such as movement against the spring effect, force sensor, etc. For example, in a hydraulic system, a pressure sensor, which can detect pressure increase due to achieving contact, or in the case of electromechanical brake systems, current draw and position sensing methods which can be used to recognize the “point of contact” during brake actuation. From this signal it can also be deduced whether the air gap is too large, too small, or the correct one, and the adjustment can be derived from this or the brake can be operated taking this changed air gap into account.

[0036] In the embodiment shown here (e.g. like or similar to Fig. 4A or the explanatory text), no sliding part needs to be used, because the ability to move is a property here and not necessarily a component. In particular, the position storage 9 shown as a line in Fig. 4 (e.g. one based on friction on the floating caliper guide) does not need any sliding parts at all, since it has the property of being movable itself.

[0037] In Fig. 4A it is shown that, for example, a possible contact force from the prong spring 12 on the retraction prong 18 can also exert a friction-based contact pressure on the distal end 18B of the retraction prong 18 against the caliper guide 5.

[0038] Fig. 4A shows how a “portion of the saddle movement” (supplied at the top in the longitudinal direction of the retraction prong 18) is converted as a compensating movement by the geometry (above, shaped retraction prong 18, e.g. curved) into a movement that pushes the floating caliper 4 in its guide 5. The stanchions 17 in the floating caliper 4 and the floating caliper guide 5 are preferably so free of play that the floating caliper sliding movement is achieved without the play being used up or its effectiveness being too severely impaired (so that, for example, there is no longer sufficient pad lifting). The stanchions 17 could, for example, be inexpensive O-rings in which the retraction prong 18 can move, or the retraction prong 18 can be, for example, rust-proof, protected, covered, etc. In any case, of the many possible stanchions, those are preferred which remain sufficiently free of play even under frequent operation, vibrations, corrosion, manufacturing tolerances, etc. and which are preferably simple and cost-effective. If, for example, the optimal air gap after braking is to be 0.05 mm to 0.4 mm, the play between the stanchions 17 and the retraction prong 18 should be or remain so small that this lining lift-off is also possible and the transmission ratio (e.g. the length ratios in the area of the retraction prong 18) should also be such that this lining lift-off is also possible, which can be dimensioned using known methods. This corresponding freedom from play in conjunction with suitable materials (e.g. wear-resistant plastics, elastomers, fully or partially corrosion-resistant metals, etc.) and transmission ratio is therefore advantageous. Of course, more or fewer parts can be used to achieve the goal of moving the floating caliper. For example, "play-free guides" in the sense of components can be dispensed with and guidance can be provided solely by holes, etc. Of course, freedom for outward movement can also be provided in the design shown in Fig. 4A, so that a floating caliper can assume a better position on its own than might be imposed on it by the lifting mechanism in an unfavorable case. This could also be freedom for inward movement.

[0039] In all the designs shown here, the force required to move the floating caliper 4 in the floating caliper guide 5 depends very much on the condition between these contact surfaces, for example corrosion, dirt, changes or damage, moisture, etc. It can therefore also be important to ensure this displaceability under certain conditions, which can be achieved, for example, by ensuring that the position storage 9 offers sufficient hold (e.g. through sufficient contact force for, for example, sufficient position-holding friction) to prevent it from being displaced if the floating caliper itself jams. This can also be achieved, for example, through experiments or (long-term) observations, or for example by making certain assumptions about the condition of the floatingcaliper in the floating caliper guide up to which the floating caliper displaceability should be successful. This can also include the design or material pairing, i.e. how the guide(s) are sealed, protected, etc., or whether, for example, fully or partially corrosion-resistant materials are selected. If necessary, durable, friction-reducing materials such as stainless steel (sheet metal), Teflon, etc., can also be incorporated into the floating caliper guide, as is also done in some current brakes for various reasons. The calculations and design explained in Figs. 1 to 3 can, of course, also be applied to all of these solutions.

[0040] In operation, the braking system 100 of Fig. 4A is operable to create an air gap 150 between the pads 6, 7 and the disc 2 at the end of a braking event to reduce drag and energy loss from friction. A start of a braking event begins with actuating the piston 8 to urge the inner brake pad 6 into engagement with the brake disc 2 and applying a clamping force to the brake disc 2 between the inner pad 6 and the outer pad 7. In response to applying the clamping force, the brake caliper 4 slides relative to the caliper guide 5 in an axial direction.

[0041] In response to moving the brake caliper 4 relative to the caliper guide 5, the proximal portion 18A of the retraction prong 18 likewise moves in an axial direction. The axial movement of the proximal portion 18A of the retraction prong 18 causes the distal portion 18B of the retraction prong 18 to be displaced in a radial direction to store a retracting force. Displacing the distal portion 18B of the retraction prong 18 may include urging the retraction prong 18 outward in a radial direction within the brake caliper 4, such as shown in the lower half of Fig. 4A, where the retracting force may be stored in the prong spring 12. More specifically, the retraction prong 18 is able to move inward toward the brake caliper 4 a small amount and compresses the prong spring 12 to store the retracting force. Alternatively, displacing the distal portion 18B of the retraction prong 18 may include deflecting (i.e., bending) the distal portion 18B of the retraction prong 18, which stores the retracting force within the retraction prong 18.

[0042] At the end of the braking event (i.e., the rotational speed of the brake disc 2 has reached a desired value), the piston 8 is actuated to release the clamping force on the brake disc 2. As mentioned above, removing the clamping force does not, by itself, retract the brake pads 6, 7, and an air gap is not created. The air gap is created in response to releasing the clamping force on the brake disc 2 by moving the inner brake pad 6 and the outer brake pad 7 out of engagement with the brake disc 2 using the stored retracting force. More specifically, the stored retracting force isexerted on the retraction prong 18, which moves the brake caliper 4 relative to the caliper guide 5 to move the inner brake pad 6 and the outer brake pad 7 out of engagement with the brake disc 2.

[0043] In the implementation of the braking system 100 shown in the upper half of Fig. 4A, the retraction force stored in the retraction prong 18 causes the retraction prong 18 to return to a generally straight configuration. The energy stored in the retraction prong 18 acts against the stanchions 17 causing the caliper 4 to move relative to the caliper guide 5 into an equilibrium position. As described above, moving the caliper 4 following the end of the braking event causes the air gap to be created between the outer pad 7 and the brake disc 2 while the actuation of the piston 8 causes the air gap to be created between the inner pad 6 and the brake disc.

[0044] Similarly, in the implementation of the braking system 100 shown in the lower half of Fig. 4A, the retraction force stored in the prong spring 12 urges the retraction prong 18 against the caliper guide 5, and friction between the distal portion 18B and the caliper guide 5 causes the retraction force to act against the stanchions 17 causing the caliper 4 to move relative to the caliper guide 5. More specifically, the retraction prong 18 pivots and slides relative to the caliper stanchions 17A and the guide stanchions 17B to cause the relative movement between the caliper 4 and the guide 5. The relative movement between the caliper 4 and the guide 5 at the end of the braking event causes the air gap to be created between the outer pad 7 and the brake disc 2 while the actuation of the piston 8 causes the air gap to be created between the inner pad 6 and the brake disc.

[0045] Another variant is shown in Fig. 4B, where the portion of the floating caliper movement 19 can now be supplied as a compensating movement essentially normal to the longitudinal axis of the retraction prong 18, and the stanchion 17 causes the sliding movement between the stored position on the floating caliper guide 5 and the floating caliper 4. For this purpose, at least one stanchion could also be a hinge point, pivot bearing, pin in a hole, etc., as shown in Fig. 4B as pivot point 20. However, a hinge point, pivot bearing, pin, etc. could develop play due to vibration, frequent operation, corrosion, manufacturing tolerances, etc., could also weaken the retraction prong 18 (risk of breakage), could be more complicated and expensive, and could complicate assembly. Wear and widening of a pivot point 20 is shown in Fig. 4B by the oval bearing contour around the pivot point 20, and can reduce the extent of the sliding movement here.

[0046] Therefore, the implementation as shown in Fig. 4A is preferred, e.g. without a pivot point, pivot bearing, pin, etc. A "support structure" that supports a brake caliper in a floatingmanner may also be unnecessary here, because the floating caliper can also be guided or supported directly, as in known designs of conventional floating caliper guides. A support structure is also not included in Figs. 4A and 4B and is not absolutely necessary or even unnecessary. A variant that is as simple as possible can be very easily constructed and installed, e.g. by simply inserting it into the stanchion 17 (e.g. O-ring, hole, rollers, etc.). However, this would not involve any joint point, pivot bearing, pin in a hole, etc., nor would its own rotational movement around a pivot or joint point arise. Instead, a complex movement sequence would arise that depends on the elasticity and friction behavior of the stanchion 17 in all adjacent areas, as well as on the exact type of supply of the floating caliper movement component, i.e., how and in what way this movement has freedoms or predetermined behaviors (e.g., guides, movement restrictions, etc.). In Fig. 4B, a joint or pivot point 20 can therefore be clearly identified both as part of and as the pivot point 20 of the movement, whereas in the preferred variant (Fig. 4A), this part is not present, and the position of a pivot point 20 is not apparent, because there is an angular change between the caliper stanchion 17A on the floating caliper 4 and the guide stanchion 17B on the floating caliper guide 5. There is therefore a movement sequence here, whereby the size of the floating caliper displacement movement results from the change in angle of the displacement part, the precise sequence on the play-free guides and other influences such as actuating force supply etc. and to calculate this sequence neither the position of a pivot point 20 is required nor is it known. This movement can also change due to, for example, temperature or age-related changes in, for example, elasticity, friction, etc. In this case, it is therefore necessary to ensure, for example using known mathematics based on angles, that the corresponding floating caliper displacement movement is caused even without a pivot or joint point(s).

[0047] Fig. 4A shows a radial biasing force from a prong spring 12, whereby (if this variant is used) the retraction prong 18 can be pressed, for example, with a spring effect, thus establishing the position hold through friction between the caliper 4 and the caliper guide 5 at the line 180 of the position storage 9 (at the very bottom). This can also be set up particularly easily with a double effect (i.e. also on the other, here upper side of the floating caliper), whereby under certain circumstances only one spring effect between the double structure is sufficient, thus enabling symmetrical floating caliper 4 movement on both floating caliper guides 5. In this variant, it is preferable not to use a "pivot point" as shown in Fig. 4B, because such a pivot point 20 (or two inthe case of a double version for both floating caliper guides) could absorb the possible contact pressure and not pass it on to the necessary friction for the position storage 9.

[0048] If both floating caliper guides have retraction prongs 18, these can also be simplified (e.g., as a continuous, possibly resilient rod). A possible contact force 12 could also be arranged between them (e.g., as a spring (effect)). For further simplification, this spring effect could also be implemented without an additional component, so that, for example, a rod exerts the possible contact forces on both floating caliper guides through its own spring effect, thus, for example, also having a resilient shape (e.g., an omega-like loop, etc.) at any location (e.g., the center).

[0049] All of the pad lifting movements presented can of course also be applied to multi-disc or multi-disc brakes, whereby, for example, the contact parts of the rotating package can be lifted from those of the stationary package and, for example, the distribution of this total movement between the individual disks can be carried out by spring effects, transmissions, levers, etc.

[0050] In summary, the brake pad lift presented here can lift one or all of the pads of a preferably non-linear, preferably electrically actuated, preferably floating caliper disc brake (or multi-disc brake) by not braking (no longer intended braking effect) and / or the lifting process of the brake pads can be triggered by a brake control command. The lifting process can also be derived from the brake pad contact piston 8, have its own actuator, or result from spring action. At least one retraction aid can also help ensure that at least one brake pad follows the lifting movement. The non-linearity can also be used to cause the air gap to be overcome more quickly than with a linear brake, for example with the same actuator motor. Overcoming the air gap can also be made as fast as possible, especially when actuating, while the lifting can also be made slower, for example. The application or lifting process can also be made as imperceptible as possible (e.g. without any backlash). It can also depend on influences or conditions and come from the brake control system or from outside. The air gap can also be determined from preferably light braking applications, or a setting can be derived from this. Electric is preferred because it easily allows a retracting movement of the brake actuator, which can also be supported by a spring effect under certain circumstances. If necessary, freedom for more outward movement 13 (or less outward movement) can give the floating caliper in the area of this freedom the additional freedom of movement that it also has with conventional floating caliper brakes. The brake pad lifting movement is carried out with respect to a stored position 9, which assumes a different stored position 10 when the pad wears, thus causing the pad to lift even when the pad wears. If acompensating movement is also used, the pad lifting can take place with practically constant accuracy regardless of the strength of the braking effect. To extend the floating caliper, at least one position storage mechanism (9) is ideally able to support the necessary force to overcome jammed floating calipers (which, for example, are prevented from being extended due to excessive friction between the floating caliper and the floating caliper guide). The design shown (also using examples) should be applied to enable extension in the cases to be covered. If multiple pad lifting movements are applied, they should be symmetrical enough to avoid problems such as jamming.DEFINED AIR GAP FOR DRUM BRAKES

[0051] While in simplex and duplex drum brakes the lifting of the pads (to create an air gap against dragging pads) is possible, for example, by at least one spring of any design from Fig. 5, it can be more difficult to ensure lifting with a defined air gap in servo drum brakes with power transmission from one shoe to the other, especially in those acting in both drum rotation directions (duo-servo).

[0052] Since the lining surface should generally be kept at a defined distance from the rotating or moving friction surface, but only these friction partners experience this distance and usually no other part in the brake, it is fundamentally difficult to create this air gap in a defined manner with regard to the relatively moving friction surfaces. The braking system 200 described below can be used in this form or in a modified form (also in all other friction brakes): It is proposed to use the pressing movement, as this is powerful, to move a moving part to a position where it remains for a subsequent lifting movement, which can be achieved, for example, by a pin placed on the armature plate (at least a part that is, for example, immovable with regard to the brake assembly or, in this case, expediently immobile) by means of a frictional connection 30. Since the pressed- on lining layer is now "stored" by the pressing process, a defined movement to lift off this lining can be carried out after this braking, for example by means of a lining lifting spring (also with a stop) 28. Since the "stored position" is determined by the stronger braking (because more contact pressure movement results in greater braking effect), a defined return stroke (as shown, for example, by the stop in Fig. 5) can certainly achieve an averagely good or usable lift within a certain accuracy of the air gap. The accuracy of the lift can be further increased according to the invention if, for example, a drive-defining movement 29 (Fig. 5 right) is included, i.e., as shown by the wedge movable with arrows, the (frictionally) engaged part is displaced further when the pad stroke is small, or displaced less when the pad stroke is large, so that accordingly, regardlessof the pad stroke, an identical or similar position of the (frictionally) engaged part results and thus a defined lift stroke leads to a well-precise position of the brake shoe 21 after the brake is released with a small tolerance in the air gap. Of course, only or primarily a drive-defining movement 29 can be used, even without additional stroke from spring(s). If necessary, a compliant behavior can also be used to better support or enable the movement sequence.

[0053] However, it is also suggested, if necessary, to design the release movement as shown in Fig. 5 on the left: in this case, the (frictional) engagement on the anchor plate assumes its position only determined by the pad movement. However, if little pad travel has been made, a (smaller) pad lifting movement 27 (indicated by arrows on the wedge-shaped part) is introduced when the brake is released. However, with greater pad travel, a larger one is introduced, so that an air gap with a small tolerance can be set after braking. Here, too, only or predominantly a pad lifting movement 27 can of course be used, even without additional travel from spring(s). If necessary, a flexible behavior can also be used to better support or enable the movement sequence. These movements (e.g. of the arrows or wedges or any other parts suitable for this purpose) can be derived from the actuator movement or the spreader movement in all of the methods shown here, for example, and all of the “position storage” that falls under “frictional engagement on the anchor plate” can of course also be held in place in other ways in everything presented here, such as via ratchets, locks, mechanically, electrically, magnetically, etc. If necessary, all or some of the parts that move when pressed (e.g. brake shoes 21) can be equipped with such or similar lifting devices, which can of course also be used in all types of friction brakes. For this purpose, Fig. 6 shows, for example, a “base lifting part” that only needs to have a similar effect, but can also look different: This base lifting part 35 could, for example, be pulled down onto the anchor plate located under the shoe, for example with a spring load, in Fig. 6 and build up the above frictional connection in the star-shaped area on the shoe with its head and, for example, be so elastic in the pressing direction that it replaces the base lifting spring from Fig. 5. The effect from Fig. 5 can therefore also be achieved with parts that look different, if they have the described effect (lifting movement against a location that is more or less well “stored” when pressed on, ideally sufficiently well for the effect).

[0054] Fig. 5 shows a drum brake system 200 with an expander 23 (for pressing force at braking) where spring(s) 31 can push the brake shoe(s) 21 with brake lining 22 away from the brake drum 3 where pin(s) or roll(s) 24 can guide the shoe(s) 21 to a lifted position with definedair gap. Straight or shaped guide(s) or stop(s) 25 that also could be rolling 26 or lever guide(s) with angle 32 also can assist to take a lifted position with defined air gap but also can guide the shoes 21, e.g. in case of a servo-drum-brake. In Fig. 5 the position is stored with a friction connection 30 to the anchor plate where, comparable with the disc brakes, a pad lifting spring with stop 28 can create a pad lifting motion 27 that lifts the shoes 21 with lining after braking and a driving motion 29 can be used to achieve better accuracy for the pad lifting motion.

[0055] Fig. 6 is a simple solution with regard to reliability, space requirements, weight and costs, and shows a pad lifting device according to the invention, which, particularly in servo drum brakes, causes the shoes on the end facing away from the spreader 23 to lift off. Duo servo brakes can act in both directions of drum rotation because the secondary shoe 2 IB in the direction of rotation hits a stop at the spreader 23 (in Fig. 6 the shoe 2 IB to the right of the spreader 23 would be secondary, e.g. at the stop of the pin) and the primary shoe 21 A (in Fig. 6, e.g. on the left) accordingly introduces the actuating movement, which in Fig. 6, e.g. via a wear adjuster at the lower end of the shoe 21A, actuates the secondary shoe 21B both as an actuating force and as a braking force (at least one component), and when the drum 3 rotates in the opposite direction, these processes occur in reverse. This means that two opposite positions of the shoes are possible depending on the direction of rotation. The floating motion of the expander 23 is given completely or partially to the shoe with lining lifting mechanism 34 (meaning that the shoe 21 is equipped with a lining 22 and the contact of the lining 22 to the drum 3 shall be lifted by a lifting mechanism 34). The floating motion can be brought e.g. by a spring 31 to a well defined location, e.g. to the center. A sticky friction part 33 can reduce the floating motion. A lifting motion is supplied to the shoe(s) 21 at a side opposite to the expander 23 which is indicated in the lower part of the lifting mechanism 34 by e.g. a spring and a linkage 38. Alternatively to the lifting mechanism 34, at least one simplified principle using flexibility (for pad retraction) and friction can be used indicated by the shoe 21 with lining lifting part 35.

[0056] Spring-based pad lifting methods could, on the one hand, lift one pad too little, but on the other hand, lift it too much, so that the other one then begins to drag. According to the invention, it is proposed that the following can also be used if necessary: The sliding movement that the spreader 23 performs when pressing the pads 21 is picked up (in full or as part of the movement) and translated into the correct direction and size via a pad lifting mechanism 34, i.e., via a pivot point (here, for example, the drum rotation axis) and the geometry (e.g., the length ratio, etc.) ofthe part attached above and below in Fig. 6, translated into the correct direction and size. So, if in Fig. 6 the counterclockwise direction of rotation of the drum has brought the right shoe to the right stop on the spreader 23, the spreader 23 moves to the left when the left shoe is pressed. However, the lower ends of the shoes 21 move to the right due to being carried along by the drum 3, which is also what the lower part of the pad lifting mechanism 34 does through its pivot point and through its correctly selected geometry (ratio of the upper and lower lengths, angle, etc.) in the correct path of its rotary movement.

[0057] If necessary, targeted behavior (e.g. flexible, springy, etc.) can also be used to better support or enable the movement sequence, especially if the sequence is "over-defined or similar", i.e. if the upper position of the shoes 21 is determined by guides, for example, and thus the lower position is no longer freely selectable but is restricted. Particularly with duo-servo drum brakes (and with simplex brakes, where the spreading mechanism can make a compensating movement to achieve the same or similar contact forces on both pads), there may be play in the compensating movement of the spreader 23, which is applied to one side depending on the direction of rotation. This play can reduce the magnitude of the pad lifting movement 27 and can therefore be designed to be small; recommended at the stops limiting the play is less than 1 mm. The stops limiting the play should also be located close to the spreader 23 (e.g., each stop should be no farther away than twice the spreader dimension between the spreader contact points, i.e., the spreader diameter), to prevent the play from being unintentionally changed so drastically by different lengths (e.g., due to thermal expansion, tolerances, etc.) that the pad lifting effect is reduced. However, force(s) or movement(s) can also be supplied to the compensating movement of the spreader 23 in order to assume a (as far as possible) precise position within the play range in order to execute the pad lifting movement 27 more precisely. For example, at least one spring (action) 31 can bring the compensating movement to a more or less well-defined point, for example in (approximately) the middle of the play. This compensating movement can also be used to draw conclusions about the braking force, since it is caused by the drag force of the pads. For this purpose, the compensating movement can also be recorded, for example by measuring the distance or by contacts etc. at the stops, etc. In combination with a spring action, the strength of the drag force can also be recorded, for example by the size of the drag movement or by reaching a switching position (e.g. a stop as a contact). This allows the strength of the braking effect or the onset of the braking effect to be recorded, possibly even in a small part of the braking effect, and can be used, if necessary, toincrease accuracy or to protect against inaccurate braking. For example, it is possible to compare whether the expected drag force occurs with the corresponding brake setting or which setting is necessary to achieve the corresponding drag force. Deviations can be used to correct or influence the setting (e.g., contact pressure position).

[0058] In Fig. 6, alternatively or additionally, a static friction part 33 can also prevent or reduce the compensating movement (e.g. rotational movement of the part supporting the spreader), particularly during the pad lifting movement, in order to lose little to no movement for lifting here through the compensating movement. The function of the static friction part 33 can also be at least partially taken over by another part, so that the static friction part 33 may not even have to be present as a separate component. This would be characterized by the lifting movement functioning correctly (i.e. with pad lifting) without a separate static friction part 33 being recognizable. The static friction can also be deliberately caused, for example, by a spring-loaded part (e.g. pin). Both (supply of force, static friction part) can be helpful or important, especially in the case of greater play (which can arise, for example, due to aging), in order to carry out the lifting movement as necessary. The combination of the transmission of the pad lifting mechanism 34 (which determines the lifting stroke on the pad), if applicable static friction part 33, if applicable supply of force or movement, force-displacement behavior of the brake pad 22, elastic and plastic deformability can also be used in conjunction with play to shape the size of the pad lifting movement so that the lifting occurs across tolerances. Of course, so much play or elasticity can also be intentionally provided that the lifting occurs (even across tolerances), so for example without this intentional play or elasticity too much lifting movement would occur (i.e. the other pad would then come into contact, for example). The interaction of the parts, play and air gap can also be used to apply one shoe first during the contact movement via the pad lifting mechanism 34, e.g. the secondary one, which can result in a softer application of the brake.

[0059] With the above explanations, this pad lifting movement could be used in both drum directions of rotation (since in directions other than the above, everything above occurs in exactly the opposite way) as pad return after actuation for a precisely defined air gap on both shoes. To do this, for example, before mounting the drum, the position of the two shoes in relation to the drum would be correctly adjusted, i.e. with the correct air gap between both, e.g. finely adjusted with a thread that engages one of the shoes at a favorable point. A favorable point results in conjunction with a favorable transmission ratio of the geometry from Fig. 6 (upper and lower length of the padlifting mechanism 34, angle, etc.) from how much the pads are moved at the pivot point on the shoe for braking, as this is also favorable for the subsequent return movement. Of course, there can also be a ± component that proves helpful, for example, in practice or from calculations.

[0060] However, if instead of a fixed pre-setting an application point is installed which can be automatically moved to a favorable position by force, the high pad contact pressure can carry out the adjustment itself, for example by bending it slightly plastically, shifting it more or less permanently, etc. This is indicated in the lower area of the pad lifting mechanism 34, for example with a spring and the linkage rod 38 on the left brake shoe 21, although these purposes can of course take on any desired arrangement. This pad lifting mechanism 34 would automatically move in the other direction of rotation without any intervention, i.e. move back in the correct lifting direction, and can therefore remain in the correct, self-established setting. However, in the event of a correspondingly incorrect adjustment, it can of course be brought back into a new, remaining setting by means of high pad contact pressure, for example by adapting to pad wear, even if it occurs unevenly on the two shoes, and it can also adapt correctly to the new contact pressure conditions after the pad has been replaced. Permanent here means that the setting remains until the high contact pressure brings about a better adjustment. Of course, the same function, or one with the same or similar effect as that described here, can also be achieved with completely different appearance and parts. For example, the spreader 23 can be on a gear shaft of an actuator and this assembly can be mounted so as to be rotatable about the brake drum axis and at the same time be part of the pad lifting mechanism 34.

[0061] Fig. 7 shows a particularly simple pad lifting mechanism 34 in which the displaceability under the pad contact pressure occurs in an elongated hole or larger hole of any shape with play 36 and a spring pressure 37 holds the position until the pad contact pressure causes it to move to a suitable location. The principle is therefore as shown in Fig. 6, only simple sheet metal parts with holes can be used. Relocatability at lining pressing force is made possible with a hole with clearance to store a position 36. An elastic pressing 37 maintains the position until the lining pressing force moves it to an appropriate position.

[0062] Of course, the arrangements shown hardly operate completely without errors in the air gap adjustment, due in part to imperfect movements, but also because the brake pads (and possibly other components such as roller bearings) do not have a constant force-displacement relationship, i.e., their force-displacement relationship is non-linear. Therefore, according to the invention, theair gaps can be selected to be large enough that, even under this imperfect behavior, at least a liftoff is achieved, albeit with a tolerance relative to the (e.g., symmetrical) ideal value. The "correct" air gap is therefore also seen here according to the invention in such a way that, despite the different thermal expansions of the various parts (e.g. drum expands and reduces braking effect, shoes or armature plate expand and increases braking effect, etc.) and the different time sequences (drum reacts quickly, shoes slower, armature plate even slower, etc.), it does not cause the linings to grind when the brakes are not being braked. This may also be the case with tolerances (e.g. accuracy of wear adjustment, manufacturing, etc.) and other influences (i.e. those whose cause cannot be (fully) explained). It can be determined, for example, mathematically, through tests, simulations, etc.

[0063] Of course, the above explanations can also be applied to other brakes with different parts names: For example, with a floating-caliper disc brake, one pad can be pressed directly onto the disc and the other pulled towards the disc in reaction, and both can move against an immovable part (e.g., immovable against the wheel bearing). This would correspond to the immovable part of the anchor plate, and the above movements can be used, for example, to lift the outboard pad after braking, i.e., the above mechanisms with spring effects, applied movements, etc. Of course, the above can also be applied to multi-disc or multi-disc brakes to lift the pads or at least the contact points of the disc packs.

[0064] What is proposed here in particular is a so-called non-linear EMB because it is able to quickly move through air gaps where there is no contact pressure and then, as the contact pressure increases, can advantageously reduce the contact pressure speed in favor of increasing force. It is proposed here that this non-linearity (transmission ratio of the contact pressure in the respective actuated position) is selected in such a way that even a large air gap (e.g. with a cold brake) is moved through quickly, but that even with a small to very small air gap the actuator torque (the actuator force) is still sufficient to reliably actuate the EMB. Obtaining the really large displacement movement on the spreader 23 from a spreader 23 of an EMB rotating in a defined manner about an axis with respect to the defined axis is of course more advisable than, for example, obtaining the movement from a double-acting hydraulic cylinder. Movement can be detected in multiple locations, as the ultimate goal is to achieve the correct length (or angle, etc.) of movement at the shoes. This mechanism can also be applied to unidirectional servo drum brakes and servodrum brakes with or without guides (24, 25, 26, 32), possibly with the appropriate modifications, since their movement sequences are somewhat different.

[0065] In the case of unidirectional and possibly bidirectional drum brakes, it is also suggested that the lifting movement can be effected differently if necessary: in these cases, the rear end of the secondary shoe in the direction of drum rotation can also be guided in a defined manner, e.g., rotatable around a pin. If at least one appropriately designed guide 24, 25, 26 is present in the force transmission area (e.g., opposite the spreader 23), the guided return movement of the primary shoe can cause a defined movement of the two connected shoes such that an air gap of a certain tolerance is created at both the spreader end and the connected end. This does not necessarily have to be the same size on both sides, but at least has a lifting effect. In principle, this can also be applied to duo-servo drum brakes if necessary; however, the rear end of the secondary shoe in the direction of drum rotation would then be guided in a defined manner to allow the necessary freedom acting in both directions of drum rotation. This would mean, for example, that it would not be mounted on a fixed pin, but rather, for example, in a guide that creates a defined stop position. In general, therefore, one shoe end assumes a defined position after the brake is released, for example defined on a pin 24, and in this position in this design variant at least one opposite shoe end also comes into a defined position (possibly also via a guide 24, 25, 26). This means that the other shoe at this end can also come into a defined position via the force transmission part, and this shoe can also come into a defined position at the other end (spreader end) via a guide 24, 25, 26, so that in practice all shoe ends can come into a more or less well-lifted position. An “end” here is not the last point of a shoe but is always located more at an upper or lower end point in Fig. 5 than in the middle.

[0066] Several instances have been discussed in the foregoing description. However, the aspects discussed herein are not intended to be exhaustive or limit the disclosure to any particular form. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the disclosure. The terminology that has been used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations are possible in light of the above teachings and the disclosure may be practiced otherwise than as specifically described.

Claims

CLAIMSWhat is claimed is:

1. A braking system for a rotating machine including a brake disc, the braking system comprising: a first friction lining and a second friction lining arranged for clamping engagement with the brake disc; a caliper guide coupled to the rotating machine; a brake caliper slidably supported by the caliper guide and operably engaged with each of the first friction lining and the second friction lining, wherein the brake caliper includes a piston operable to urge the first friction lining into engagement with the brake disc; a retraction prong extending in a radial direction from a proximal portion engaged with the brake caliper to a distal portion frictionally engaged with the caliper guide; wherein the retraction prong is axially resilient and configured exert a retracting force on the brake caliper and the caliper guide opposing the piston; wherein the distal portion of the retraction prong is biased toward engagement with the caliper guide; and wherein the retracting force on the caliper guide and the brake caliper is configured to move both of the first friction lining and the second friction lining out of engagement with the brake disc.

2. The braking system of claim 1, wherein the retraction prong is slidable in a radial direction relative to the brake caliper.

3. The braking system of claim 2, wherein the brake caliper further includes a caliper stanchion slidably engaged with the proximal portion of the retraction prong, and wherein the caliper stanchion is arranged to limit axial movement of the retraction prong relative to the brake caliper.

4. The braking system of claim 3, wherein the caliper stanchion includes a pair of stanchion posts and wherein the retraction prong is arranged between the pair of stanchion posts.

5. The braking system of claim 4, wherein the caliper guide includes a guide stanchion slidably engaged with the distal portion of the retraction prong, and wherein the guide stanchion is arranged to limit axial movement of the retraction prong relative to the caliper guide.

6. The braking system of claim 5, wherein the guide stanchion includes a pair of stanchion posts and wherein the retraction prong is arranged between the pair of stanchion posts.

7. The braking system of claim 3, wherein the retraction prong is flexible and is configured to flex due to relative movement between the brake caliper and the caliper guide and wherein the retracting force is generated by flexing the retraction prong.

8. The braking system of claim 1 , wherein the retraction prong is further defined as a first retraction prong and a second retraction prong, and wherein the first retraction prong and the second retraction prong are arranged on opposing sides of the brake caliper.

9. The braking system of claim 1, further comprising a prong spring arranged between the brake caliper and the proximal portion of the retraction prong, wherein the prong spring biases the retraction prong in a radial direction toward engagement with the caliper guide.

10. A method of operating a braking system including a brake disc, a first friction lining and a second friction lining arranged for clamping engagement with the brake disc, a caliper guide, a brake caliper slidably supported by the caliper guide and operably engaged with each of the first friction lining and the second friction lining, the brake caliper including a piston actuatable to urge the first friction lining into engagement with the brake disc, and an axially resilient retraction prong extending in a radial direction from a proximal portion engaged with the brake caliper to a distal portion frictionally engaged with the caliper guide, the distal portion of the retraction prong biased toward engagement with the caliper guide, the method comprising the steps of: actuating the piston to urge the first friction lining into engagement with the brake disc, applying a clamping force between the first friction lining and the brake disc to generate movement of the brake caliper relative to the caliper guide to urge the second friction lining into engagement with the brake disc in response to applying the clamping force; in response to moving the brake caliper relative to the caliper guide, displacing the distal portion of the retraction prong in a radial direction to store a retracting force;actuating the piston to release the clamping force on the brake disc; in response to releasing the clamping force on the brake disc, moving the first friction lining and the second friction lining out of engagement with the brake disc using the stored retracting force.

11. The method of claim 10, wherein the step of displacing the distal portion of the retraction prong in a radial direction is further defined as sliding the retraction prong in a radial direction relative to the brake caliper.

12. The method of claim 10, wherein the braking system further includes a prong spring arranged between the brake caliper and the proximal portion of the retraction prong, and wherein the step of displacing the distal portion of the retraction prong in a radial direction to store a retracting force is further defined as compressing the prong spring with the retraction prong and storing the retracting force in the prong spring.

13. The method of claim 12, wherein the step of moving the first friction lining and the second friction lining out of engagement with the brake disc is further defined as exerting the retracting force stored in the prong spring on the retraction prong and moving the brake caliper relative to the caliper guide to move the first friction lining and the second friction lining out of engagement with the brake disc.

14. A braking system for a machine including a friction surface, the braking system comprising: a first friction lining and a second friction lining arranged for engagement with the friction surface; a guide engaged with one of the first friction lining and the second friction lining; a pressing mechanism operable to urge the first friction lining into engagement with the friction surface; a retraction member frictionally engaged with the caliper guide; wherein the retraction member is configured to exert a retracting force on one of the first friction lining and the second friction lining opposing the pressing mechanism; wherein the retraction member is biased toward engagement with the guide; andwherein the retracting force on one of the first friction lining and the second friction lining is configured to move both of the first friction lining and the second friction lining out of engagement with the friction surface.

15. The braking system of claim 14, wherein the retraction prong is slidable in a radial direction relative to the first friction lining and the second friction lining.

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