Single pneumatic disc brake tappet with features simulating multiple tappets

Abstract

The following embodiments relate to a single pneumatic disc brake tappet with features that mimic multiple tappets. In one embodiment, a pneumatic disc brake tappet is provided, comprising: a support member; and a plate coupled with the support member, where the plate includes a plurality of raised features that mimic a plurality of pneumatic disc brake tappets. In another embodiment, a pneumatic disc brake pad assembly is provided, comprising: a friction material; and a backing plate coupled with the friction material, where the backing plate includes at least one recess shaped and positioned to receive a plurality of raised features of a pneumatic disc brake tappet, where the plurality of raised features mimic a plurality of pneumatic disc brake tappets.

Description

BACKGROUND

[0001] In some air disc brake systems, when brakes are applied, air pushes two spaced-apart tappets against a backplate of an inner brake pad, which operation causes the inner brake pad to move into contact with a rotor coupled to a wheel. In other air disc brake systems, a single tappet is used that is positioned to contact the middle of the backplate. During braking, the rotor rotates and the brake pad is applied against the rotor to create a braking force. Uneven force distribution caused by the moment between the drag force of the brake pad and the reaction force of the abutment can cause uneven distribution of the braking force and, consequently, uneven wear of the inner brake pad. Various solutions have been proposed to address this problem. SUMMARY

[0002] The following embodiments relate to a single air disc brake tappet having features that simulate multiple tappets. In one embodiment, an air disc brake tappet is provided, comprising: a support member; and a plate coupled with the support member, wherein the plate comprises a plurality of raised features that simulate a plurality of air disc brake tappets.

[0003] In another embodiment, an air disc brake pad is provided, comprising: a friction material; and a backplate coupled with the friction material, wherein the backplate comprises at least one groove shaped and positioned to receive a plurality of raised features of an air disc brake tappet, wherein the plurality of raised features simulate a plurality of air disc brake tappets.

[0004] In yet another embodiment, an air disc brake system is provided, comprising an air disc brake pad and an air disc brake tappet. The air disc brake pad comprises: a friction material; and a backplate coupled with the friction material, wherein the backplate comprises at least one groove. The air disc brake tappet comprises: a support member; and a plate coupled with the support member, wherein the plate comprises a plurality of raised features that simulate a plurality of air disc brake tappets, wherein the plurality of raised features are shaped and positioned to mate with the at least one groove of the backplate.

[0005] Other embodiments are possible, and each embodiment can be used alone or in combination with others. BRIEF DESCRIPTION OF DRAWINGS

[0006] Figure 1A FIG. 1 is a schematic view of an air disc brake system of one embodiment.

[0007] Figure 1B FIG. 2 is a schematic view of longitudinal tapering wear forces on the air disc brake system of one embodiment.

[0008] Figure 2A FIG. 3 is a side view of a tappet of one embodiment.

[0009] Figure 2B This is a top view of a pushrod according to one embodiment.

[0010] Figure 2C This is a bottom view of a pushrod in one embodiment.

[0011] Figure 3A This is a schematic diagram of a brake block backplate according to one embodiment.

[0012] Figure 3B This is a schematic diagram of the push rod pushing the back plate of the resisting block in one embodiment.

[0013] Figure 4A This is a schematic diagram of a pushrod with a zero-degree tilt angle according to one embodiment.

[0014] Figure 4B This is a schematic diagram of a pushrod with a one-degree tilt angle according to one embodiment.

[0015] Figure 5A This is a schematic diagram of the tappet and brake block backplate before contact in one embodiment.

[0016] Figure 5B This is a schematic diagram of the tappet and brake block backplate in initial contact according to one embodiment.

[0017] Figure 5C This is a schematic diagram of the tappet and brake block backplate in full contact according to one embodiment.

[0018] Figure 6A This is a side view of a pushrod according to one embodiment.

[0019] Figure 6B yes Figure 6A A side view of the tappet rotated 180 degrees.

[0020] Figure 7A This is a schematic diagram of a brake block backplate having a raised surface according to one embodiment.

[0021] Figure 7B This is a schematic diagram of a push rod with a groove in one embodiment, wherein the groove is... Figure 7A Matching the raised surface of the brake block backplate.

[0022] Figure 8A This is a schematic diagram of a brake block backplate having a raised surface according to one embodiment.

[0023] Figure 8B This is a side view of a push rod with a groove according to an embodiment, the groove being... Figure 8A Matching the raised surface of the brake block backplate.

[0024] Figure 8C yes Figure 8B Perspective view of the middle tappet.

[0025] Figure 8D This is a side view of a push rod having a groove and a non-tapered top surface, according to one embodiment.

[0026] Figure 8E This is a side view of a push rod having a groove and a portion having a non-tapered but inconsistent height, according to one embodiment.

[0027] Figure 9A This is a schematic diagram of a brake block backplate having a raised surface offset from the center of the brake block backplate according to one embodiment.

[0028] Figure 9B This is a side view of a push rod having a groove and a tapered top surface according to one embodiment, wherein the groove is offset from the center of the push rod.

[0029] Figure 10A This is a schematic diagram of a brake block backplate with grooves according to one embodiment.

[0030] Figure 10B This is a side view of a push rod with a raised surface according to an embodiment, the raised surface being... Figure 10A The groove of the brake block backplate is matched.

[0031] Figure 10C This is a schematic diagram of a brake block backplate before it is installed into a braking system, according to one embodiment.

[0032] Figure 10D This is a schematic diagram of a brake block backplate being installed into a braking system according to one embodiment.

[0033] Figure 10E This is a schematic diagram of a brake block backplate installed in a braking system according to one embodiment.

[0034] Figure 11A This is a perspective view of a pushrod according to one embodiment.

[0035] Figure 11B yes Figure 11A A perspective side view of the tappet rotated 180 degrees.

[0036] Figure 12A This is a top view of a brake block backplate having a triangular raised surface, according to one embodiment.

[0037] Figure 12B yes Figure 12A A perspective bottom view of the back plate of the brake block.

[0038] Figure 13A This is a top view of a brake block backplate having a curved trapezoidal type raised surface, according to one embodiment.

[0039] Figure 13B yes Figure 13AA perspective bottom view of the back plate of the brake block.

[0040] Figures 14A-14D This is a schematic diagram of a brake block backplate with horizontal features according to one embodiment.

[0041] Figure 15A This is a schematic diagram of a single tappet with a brake block backplate and features simulating multiple tappets, according to one embodiment.

[0042] Figure 15B This is a schematic diagram of the push rod pushing the back plate of the resisting block in one embodiment.

[0043] Figure 15C This is a schematic diagram of a brake block backplate and double tappets according to one embodiment.

[0044] Figure 15D This is a schematic diagram of a double tappet push-resistance block backplate according to an embodiment.

[0045] Figure 16A This is a perspective view of a pusher having two protruding features simulating two pushers, according to one embodiment.

[0046] Figure 16B This is a side view of a pushrod in one embodiment, wherein two protruding features simulating two pushrods have non-tapered but inconsistent heights.

[0047] Figure 16C This is a side view of a pushrod in one embodiment, wherein one of the two protruding features simulating two pushrods is tapered.

[0048] Figure 16D This is a side view of a pushrod in one embodiment, wherein the two protruding features simulating two pushrods are both tapered.

[0049] Figure 16E and 16F This is a schematic diagram of a pusher having the characteristics of simulating the deviation of multiple pushers, according to one embodiment.

[0050] Figure 17A This is a schematic diagram of a pushrod having a brake block backplate and features simulating multiple pushrods, according to one embodiment.

[0051] Figure 17B This is a schematic diagram of a pushrod having a brake block backplate and features simulating multiple pushrods, according to one embodiment.

[0052] Figure 18A This is a schematic diagram of a pushrod having a brake block backplate and features simulating multiple pushrods, according to one embodiment.

[0053] Figure 18B This is a schematic diagram of the push rod pushing the back plate of the resisting block in one embodiment.

[0054] Figure 19A This is a perspective view of a pusher having two protruding features simulating two pushers, according to one embodiment.

[0055] Figure 19B This is a perspective view of a pusher having two protruding features simulating two pushers, according to one embodiment. Detailed Implementation

[0056] General Overview of Pneumatic Disc Braking Systems Now turn to the attached image. Figure 1A This is a schematic diagram of a pneumatic disc brake system 100 according to an embodiment. Figure 1A As shown, the system 100 includes an inner brake block 110 and an outer brake block 120 adjacent to a brake rotor 130 connected to the wheels of a vehicle. Each brake block 110, 120 includes a friction material (e.g., a mixture of particles of different materials) configured to slow the rotation of the rotor 130 when the brake blocks 110, 120 press against the rotor. Each brake block 110, 120 is bonded to a respective backing plate 115, 125, which may be made of, for example, cast iron or steel. A floating caliper 135 engages the two brake blocks 110, 120.

[0057] In operation, when vehicle braking is applied (e.g., when the driver depresses the brake pedal or when the autopilot system generates an electronic signal to apply braking), air enters the service brake chamber 140 through supply port 145, applying pressure within the diaphragm 150. This pressure causes the diaphragm 150 to expand, thereby exerting force on the pressure plate 155 and push rod 160 and moving them forward. Push rod 160 acts on a cup holder in an internal lever 165, which pivots on an eccentric bearing 170 to move bridge member 175. Bridge member 175 moves against return spring 180, transmitting motion to support member (e.g., threaded tube (not shown)) and tappet 200, which contacts the back plate 115 of the inner brake block to bring the inner brake block 110 into contact with rotor 130. Further movement of bridge member 175 forces floating caliper 135 (sliding on two fixed guide pins (not shown)) away from rotor 130. This, in turn, pulls outer brake block 120 toward rotor 130. The clamping action of brake blocks 110 and 120 on rotor 130 applies braking force to the wheels. When the vehicle brakes are released, the air pressure in the service brake chamber 140 is expelled, and the return spring 180 in bridge 175 and the return spring 185 in service brake chamber 140 return the pneumatic disc brake to a neutral, non-braking position. It should be understood that this is merely an example and other configurations may be used.

[0058] As described above, when braking is applied, air forces the tappet 200 (connected to a support such as a threaded tube) into contact with the back plate 115 of the inner brake pad. The combination of the tappet 200 and the threaded tube may sometimes be referred to herein as a plunger or piston, and the tappet 200 may sometimes be referred to herein as a pressure plate. In a dual-tappet braking system, a pair of spaced-apart tappets (and threaded tubes) are used to distribute the applied force over a large area of ​​the back plate 115. This results in a relatively even distribution of braking force on the back plate 115 and therefore on the rotor 130, which leads to relatively uniform wear of the inner brake pad 110.

[0059] Each time braking is applied, the brake pads 110, 120, and rotor 130 wear. Over time, this increases the running clearance between the brake pads and rotor, and between the tappet and backing plate 115. The braking system 100 may have a mechanical mechanism (not shown) for each of the two tappets to adjust the relative position of each tappet to compensate for the increased running clearance. To reduce cost and complexity (especially in vehicles where robustness of dual-tappet braking is not required), a single tappet can be used, as using only a single tappet would eliminate half of the components in the mechanical mechanism for compensating for the increased running clearance.

[0060] Unlike dual-pushrod braking, which distributes braking force across the left and right sides of the backplate 115, the pushrod in single-pushrod braking is typically positioned at the center of the backplate 115. Therefore, using a single-pushrod brake can result in uneven distribution of braking force and thus uneven wear of the inner brake pad 110 compared to dual-pushrod braking. It should be noted that dual-pushrod braking does not eliminate tapering wear, but it is a common method to reduce this phenomenon because it helps to distribute braking force more evenly. Another point to note is that another common method to reduce tapering wear is to use multiple pushrods or pistons and sometimes vary their size relative to the leading and trailing edges of the brake pads to help mitigate tapering wear. More specifically, when the rotor 130 rotates, the leading edge of the inner brake pad 110 may wear faster due to the uneven force distribution caused by the torque generated between the brake pad drag force and the support reaction force. These forces will be referenced... Figure 1B Let's have a discussion.

[0061] like Figure 1B As shown, the pressure distributed on the inner brake block can be referred to in two ways. The first way is the static load under static conditions. Under static conditions, such as... Figure 1B As seen in the diagram on the left, the force distribution has a parabolic shape. The second approach is dynamic load under dynamic conditions. Here, the forces output to the brake pads are mostly right-angled triangular in shape, with a larger amount of pressure at the leading edge. Under dynamic conditions, the uneven force distribution is caused by the torque generated between the brake pad drag force and the support reaction force, such as... Figure 1BAs shown on the right. The maximum force at the leading edge of the brake pad is greater than the force at the trailing edge. Here, the force at the trailing edge is referred to as the minimum force. Typically, the force at the leading edge may be approximately one-third greater than the average pressure. Typically, the force at the trailing edge may be approximately two-thirds of the average brake pad pressure. This pressure imbalance under dynamic conditions can cause each edge of the brake pad to move and / or wear a different distance during braking, thus resulting in tapered brake pad wear.

[0062] Various solutions have been proposed to address this problem, but these solutions are often complex and expensive. The following embodiments provide different solutions to this problem. It should be understood that these embodiments can be used individually or in combination with each other.

[0063] Example of a tapered tappet used to reduce brake pad wear. In one embodiment, a tapered tappet is used in a single-piston system (although tapered tappets can also be used in multi-piston systems, or, as discussed below, in a single-piston system having characteristics simulating multiple tappets) to provide a more uniform distribution of braking force and brake pad wear. More specifically, in one embodiment, the tappet 200 is angled / profiled (e.g., at a one-degree angle) relative to the backplate 115 such that one end of the tappet 200 contacts the trailing edge of the backplate 115 before the other end of the tappet 200 contacts the leading edge of the backplate 115. This additional force on the trailing edge of the backplate 115 can partially or completely counteract the force generated by the rotor 130 on the leading edge of the backplate 115, thereby potentially avoiding uneven distribution of braking force and consequently uneven wear of the inner brake pad 110. This feature, and others, will be discussed in more detail below.

[0064] Please refer to the attached diagram again. Figure 2A , 2B Views 2C and 2C are the side view, top view, and bottom view of the tappet 200 in this embodiment, respectively. The tappet 200 includes a portion configured to connect the tappet 200 to a support member. For example, Figure 2A and 2B The mating threaded connection between the threaded tube 210 and the connecting member 205 of the push rod 200 is shown. Alternatively, the threaded tube 210 can be connected to the push rod 200 by coiling a portion of the body of the push rod 200 onto the threaded tube 210 using an intermediate bushing (not shown). Other securing methods are conceivable. (Although the threaded tube 210 is shown in this example, it should be understood that other types of support members (e.g., unthreaded tubes, rods, etc.) can be used.) Figure 2C The center 230 of the indicator strut 200, which will be discussed below, can be positioned to align with the center 117 of the backplate 115 (see...). Figure 3A ).like Figure 2BAs shown, in this embodiment, the top surface 220 of the pushrod 200 is flat. In other embodiments, the top surface 220 of the pushrod 200 may have protrusions and / or recesses that can mate with mating portions on the backplate 115, as will be discussed below. This creates a unique interface such that the backplate 115 will bond to the mating pushrod 200 and vice versa. As will be discussed in more detail below, in this embodiment, the top surface 220 of the pushrod 200 is tapered / angled. Therefore, as Figure 2C As shown, when the top surface 220 of the push rod 200 is placed on a flat surface, the connecting member 205 is located at a small angle relative to the flat surface.

[0065] Figure 3A This is a schematic diagram of the back panel 115 in this embodiment. Figure 3A The overall shape of the backplate 115 shown is only an example, and other shapes may be used (some of which are illustrated in other figures in this article). Figure 3A One side of the backplate 115 shown is the side of the top surface 220 of the contact strut 200 (see...) Figure 3B And the opposite sides of the backplate 115 are glued or otherwise connected to the inner brake block 110. For example... Figure 3A As shown, the side of the backplate 115 has a groove, and the surrounding raised feature 116 generally matches the overall shape of the top surface 220 of the strut 200. Therefore, as... Figure 3B As shown, when the push rod 200 is pushed against the back plate 115, the push rod 200 is received in a recess and normally mates with the back plate 115. This connection helps the back plate 115 resist any rotation caused by the rotor 130 when it contacts the inner brake block 110, and also mates the use of the back plate 115 and the push rod 200. Figure 3A and 3B As shown, in this embodiment, the center 230 of the pushrod 200 is positioned to be generally aligned with the center 117 of the backplate 115. In other embodiments, the pushrod 200 is positioned to offset its center 117 relative to the center 117 of the backplate 115. Similarly, with Figure 2C Same, Figure 3B The connecting member 205 is shown to be located at a small angle relative to the flat surface of the back plate 115 due to the tapered / angled nature of the top surface 220 of the push rod 200 in this embodiment.

[0066] Now go to Figure 4A In a non-recessed tappet design, the axis 400, perpendicular to the axis 410 passing through the center 230 of the tappet 200, is collinear with the axis 405 defined by the top surface 220 of the tappet 200. Conversely, as Figure 4BAs shown, in the tapered tappet design, tappet 200 is machined such that its top surface 220 is angled relative to the vertical axis 400. (Instead of machining, a separate tapered component can be attached to an existing flat-surface tappet.) Figure 4B In the middle, this angle is one degree (in Figure 4B (The angle is magnified to draw attention to the tilt). A taper of one degree may be able to offset two millimeters of wear, for example. However, it is important to note that any suitable angle can be used. Furthermore, the degree of this angle can be a function of the friction material used for the inner brake block 110. For example, a relatively large angle can be used for a relatively more forgiving friction material.

[0067] As described above, since the backplate 115 is typically positioned parallel to axis 400, the top surface 220 of the tappet 200 is also inclined relative to the backplate 115. Tapered tappet 200 (see...) Figure 4A This can be used to deflect the force applied by the tappet 200 to the backplate 115 to one side, which can partially or completely counteract the uneven force distribution caused by the torque formed between the brake pad drag force and the support reaction force, which can lead to uneven braking force distribution and uneven wear of the brake pad 110. This is in Figures 5A-5C The explanation is as follows.

[0068] Figure 5A The pusher 200 is shown before contact with the backplate 115. (See image.) Figure 5A As shown, the push rod 200 is inclined downward relative to a line perpendicular to the axis 410 passing through the center 230 of the push rod 200 and the axis 415 passing through the center of the threaded tube 210. This results in one end 500 of the push rod 200 being closer to the back plate 115 than the other end 510 of the push rod 200. Therefore, when the push rod 200 is pushed against the back plate 115, the protruding end 500 of the push rod 200 (not the other end 510) makes initial contact with the back plate 115 (see...). Figure 5B ).

[0069] As the push rod 200 continues to be pushed toward the back plate 115, the entire front surface 220 of the push rod 200 contacts the back plate 115 (see...). Figure 5CTherefore, both the protruding end 500 and the other end 510 of the push rod 200 push against the back plate 115. However, as described above, due to the inclination angle in the top surface 220 of the push rod 200, the threaded tube 210 becomes slightly inclined, resulting in a small angle between the axis 410 passing through the center 230 of the push rod 200 and the axis 415 passing through the center of the threaded tube 210. Therefore, instead of providing a normal force to the center 117 of the back plate 115, the protruding end 500 of the push rod 200 generates a biasing force on the trailing edge of the back plate 115. That is, even if the center 230 of the push rod 200 is aligned with the center 117 of the back plate 115, the center of pressure is biased from the center 117 of the back plate 115 toward the trailing edge of the back plate 115, without shifting the relative position of the center 230 of the push rod 200 toward the trailing edge of the back plate 115. The eccentric force on the rear edge of the backplate 115 can partially or completely compensate for the force generated on the front edge of the backplate 115 due to the uneven force distribution caused by the torque formed between the brake pad drag force and the support reaction force. This avoids the aforementioned problem of uneven braking force distribution and the resulting uneven wear of the inner brake pad 110.

[0070] Similarly, as described above, the top surface 220 of the tappet 200 typically mates with a matching profile / groove formed in the backplate 115. This helps the backplate 115 resist rotation due to the rotational force applied by the rotor 130. This also provides a unique interface that allows the backplate 115 to bond with the matching tappet 200 and vice versa. Other bond-fit shapes may be used, as will be discussed below. Furthermore, in this embodiment, the top surface 220 of the tappet 200 is typically elongated and covers a relatively large area of ​​the backplate 115, which helps distribute braking force across the backplate 115, thereby further contributing to a more uniform braking force distribution and therefore more uniform brake pad wear. It should be noted that the elongated shape of the tappet 200 shown in the above figures is only an example, and other shapes may be used, some of which will be described below.

[0071] Similarly, in this embodiment, the overall shape of the top surface 220 of the tappet 200 is symmetrical. For example... Figure 6A and 6B As shown, this means that a 180-degree rotation of the tappet 200 will move the position of the protruding end 500 of the tappet 200 by 180 degrees. This allows the tappet 200 to be used for positioning on the backplate of the left or right side of the wheel end. Therefore, instead of manufacturing tapered tappets with different configurations for the left or right side of the wheel end (e.g., "left tapered tappet" and "right tapered tappet"), a single configuration can be used to position the protruding end 500 in the desired position by rotating the tappet 200. Once the tappet 200 is "positioned" in the desired position, the tappet 200 can be secured in place by anti-rotation devices, such as using a flexible bellows (dust cover) positioned around the rear of the tappet 200 to seal against contaminants.

[0072] The use of this "universal" tapered tappet not only reduces manufacturing complexity by requiring only a single tapered tappet design to be manufactured, but also eliminates the need to store different types of tapered tappets for different applications. Furthermore, the "universal" tapered tappet avoids the possibility of installing the wrong type of tappet at a given wheel end. This also offers advantages over alternative embodiments where the backplate is tapered and the tappet is flat, as tapered backplates are only suitable for specific wheel ends and are not universal.

[0073] There are many alternatives that can be used for these embodiments. For example, as described above, the shapes of the tappet 200 and the backplate 115 can be varied, and the features used to mate / align the tappet 200 and the backplate 115 can also be varied (the mate / alignment features are not necessarily required). Similarly, although the tapered tappet 200 is described in conjunction with a single piston design, multiple tapered tappets can be used in multi-piston braking systems (e.g., two tapered tappets can be used in a dual-tappet system), and, as discussed below, on a single piston having features that simulate multiple tappets. Furthermore, although a centered piston system has been discussed above, it should be understood that tapered tappets can be used in systems where the piston is eccentric relative to the center of the backplate.

[0074] Other embodiments and variations may be used, such as those discussed below, for example.

[0075] Examples of tappets and brake block backplates with interface features In the example tappet 200 and backplate 115 discussed above, the top surface 220 of the tappet 200 typically matches a matching profile / groove formed in the backplate 115. This provides a uniquely shaped interface that allows the specific design of the backplate 115 to bond with the specific design of the tappet 200. Besides potentially providing resistance to the forces exerted by the rotor 130 during rotation, this unique interface feature ensures that only authorized backplates can be used with a given tappet, and vice versa (e.g., to prevent competitors from producing aftermarket brake pads for a specific braking system (where a mismatched backplate may not function properly)). Furthermore, depending on the design, the interface feature can also serve as a guide for mounting the brake pad / backplate to the appropriate position in the braking system, as will be discussed below.

[0076] Instead of the matching profile / groove interface as shown in the example above, or otherwise, the backplate 115 may have one or more raised surfaces 750 that match one or more corresponding grooves 760 in the top surface 220 of the pushrod 200 (see Figure 7A and 7BThere are many possible alternatives. For example, instead of the raised surface 750 on the back plate 115 and the groove 760 in the push rod 200, the raised surface can be on the push rod 200 and the groove can be on the back plate 115. As another alternative, multiple groove / raised surface pairs can be used. In some embodiments, all grooves are on the back plate (or push rod) and all raised surfaces are on the push rod (or back plate). In another embodiment, both the back plate and the push rod have grooves and raised surfaces. Similarly, as described above, instead of the raised surface or groove on the top surface 220 of the push rod 200 serving as an interface, or otherwise, the entire shape of the push rod 200 can serve as an interface, such as... Figure 3B and 7A Like in the middle.

[0077] Many different configurations of the struts, backplate, and interface are possible. The following paragraphs provide some example configurations. It should be understood that these are merely examples, and other types of configurations can be used.

[0078] Returning to the attached diagram, Figure 8A This is a schematic diagram of a backplate 815 according to another embodiment. (The diagram is in conjunction with...) Figure 3A As can be seen from the comparison of the backplate 115 shown, the backplate 815 of this embodiment has a different overall shape (outer edge). Furthermore, this backplate 815 is configured for use with a single circular strut 800 (see...). Figure 8B and 8C It has a circular groove 840 for receiving the outer edge of the single circular push rod 800. This is consistent with... Figure 3A In contrast to the design in, Figure 3A In the middle, the pushrod 200 is a roughly elliptical shape that contacts more of the surface of the backplate 115. For example... Figure 8A , 8B As shown in Figure 8C, in this embodiment, in addition to the interface feature where the circular groove 840 in the backplate 815 matches the circular shape of the tappet 800, the backplate 815 includes a protrusion 850 that matches the groove 860 in the tappet 800. This unique interface feature ensures that only brake block backplates with matching features can be used with the tappet 800. This may also provide resistance to rotation. Furthermore, this interface feature can be used as a guide for mounting the backplate 815 into the appropriate position in the braking system by sliding the protruding surface 850 on the backplate 815 into the groove 860 in the tappet 800, as will be discussed below.

[0079] exist Figure 8B and 8C In the example taper 800 shown, the top surface of the taper 800 has a taper to provide the reaction force discussed above. However, it should be noted that a unique matching interface feature can be used without the taper feature. For example, as Figure 8DAs shown, the push rod 800 can have a non-tapered top surface, such that portions 810 and 820 of the push rod 800 on both sides of the groove 860 have the same height. As another alternative (see...) Figure 8E The portions 810 and 820 of the push rods 800 on both sides of the groove 860 can have different, non-recessed heights. This scheme is similar to the recessed design and can provide the reaction force discussed above.

[0080] Of course, there are many possible alternatives. For example, such as Figure 9A and 9B As shown, instead of the groove / protrusion surfaces 950, 960 located at the center of the brake block backplate 915 and the pushrod 900, the groove / protrusion surfaces 950, 960 can be eccentric. Similarly, as Figure 10A and 10B As shown, instead of the groove in the pushrod and the raised surface on the backplate, an opposite configuration can be used, where the groove 1060 is in the backplate 1015 and the raised surface 1050 is on the pushrod 1000. Many other configurations are possible. For example, as described above, the backplate and pushrod can each have both grooves and raised surfaces of the same or different shapes and sizes. Similarly, although Figure 9A , 9B The tappets 900 and 1000 in 10A and 10B are tapered, but as mentioned above, non-tapered tappets can be used.

[0081] As mentioned above, the interface features can be used as a guide for mounting the backplate to the appropriate location in the braking system. This will now be combined with... Figures 10C-10E Let's have a discussion. Figure 10C This is a schematic diagram of the brake block backplate 1015 before it is installed into the braking system. (See diagram below.) Figure 10D As shown, in order to install the inner brake block 1010 and the brake block back plate 1015, the brake block back plate 1015 is positioned such that the groove 1060 in the brake block back plate 1015 can slide over the raised surface 1050 of the push rod 1000. Figure 10E The fully installed inner brake block 1010 and brake block backplate 1015 are shown. Figure 10E The outer brake block 1020 and its back plate 1025, as well as the rotor 1030, are also shown.

[0082] Returning to the attached diagram, Figure 11A and 11BAnother configuration of the tappet 1100 is illustrated. This figure also shows the cover plate 1105, return spring 180, and bridge 175, although other configurations and components can be used. As these figures show, the tappet 1100 is tapered, although a non-tapered design can be used as described above. Furthermore, instead of a rectangular groove, the groove in this example is a combination of a rectangular shape 1160 and a semi-circular shape 1161, which will match the relatively protruding shape on the backplate. These figures also show that this tappet 1100, like at least some of the tappets discussed above, can be rotated 180 degrees about its central axis 1162 and oriented into the caliper during assembly to correspondingly position the plunger, thus providing versatility.

[0083] Furthermore, many different shapes and sizes of grooves (multiple grooves) / raised surfaces (multiple raised surfaces) can be used. For example, Figure 12A and 12B The backplate 1215 shown has both a recessed circular portion 1240 for receiving a pushrod with a circular profile and a raised surface 1250 with a triangular "wedge" shape that will mate with a corresponding groove in the pushrod. As another example, Figure 13A and 13B The backplate 1315 shown has both a recessed circular portion 1340 for receiving a pushrod with a circular profile and a raised surface 1350 with a curved trapezoidal shape that will mate with a corresponding groove in the pushrod. The shape can be any arbitrary shape or can have some meaning, such as the logo of the manufacturer of the brake block / backplate and the pushrod. Similarly, interface features can be shaped or placed on the backplate to supplement its strength in critical areas, such as the center of the backplate.

[0084] As described above, there are many possible alternatives, such as the groove / protrusion surface (e.g., male or female features (recesses or protrusions)) being juxtaposed between the back plate and the pushrod, and both the back plate and the pushrod including the groove and protrusion surface. Furthermore, the interface feature does not necessarily have to be located along the entire length of the pushrod or back plate. Also as described above, the top surface of the pushrod can be tapered, non-tapered, and / or have a portion with uniform or non-uniform height. Similarly, these embodiments can be used alone or in combination with the embodiments discussed above and / or below.

[0085] Furthermore, many different shapes and sizes of grooved / protruding surfaces can be used. For example, Figure 14A The backplate 1350 shown has both a recessed circular portion for receiving a pushrod with a circular shape (outer edge) and a raised surface with a horizontal feature 1362 that will match a corresponding groove in the pushrod. More specifically, in Figure 14AIn this configuration, the single horizontal feature 1362 gradually widens to the right. This can be used, for example, in a brake where the inner brake block is oriented such that it will move away from an upward taper. In this case, the brake block will move to the left to avoid self-locking into the groove / taper. Note that this can make the brake block "directional." Similarly, to address tapering wear, the taper face can be angled.

[0086] As another configuration Figure 14B The backplate 1370 shown has a single horizontal feature 1372 that tapers to the left. This can be used in a brake where the inner brake block is oriented such that the brake block will move away from an upward taper. In this case, the brake block will move to the right to avoid self-locking into the groove / taper. Note that this makes the brake block "directional" (to correspond with...). Figure 14A (The opposite approach). Similarly, to address tapering wear, the tappet face can be angled.

[0087] Therefore, in Figure 14A and 14B In this configuration, the triangular "wedge" shapes 1362 and 1372 are oriented horizontally (rather than vertically). This orientation, compared to a vertical arrangement, may help prevent contact and / or locking of the wedge shapes 1362 and 1372 between the brake block backplate interface features (wedges) and the tappet interface features (wedges) during braking.

[0088] In another configuration, two horizontally oriented wedge shapes are used, which will match corresponding grooves in the pushrods having similar features. The shapes can be tapered angles or wedge shapes, or two matching tapered angles or wedges oriented with tapers that are either away from or towards each other. Such shapes can also be used to prevent contact and potential locking between the pushrod and backplate features when the backplate slides toward or away from the pushrod features during braking.

[0089] More specifically, in Figure 14C In the middle, the backplate 1380 has a groove design 1382, wherein the feature is higher at each end and tapers towards the center. The pushrod can be angled and keyed into this shape. Note that this style may or may not tend to self-lock if the brake block moves to the right or left. This will not be a directional brake block. Figure 14D In the middle, the backplate 1390 has a groove design 1392, wherein the feature is shorter at each end and gradually widens towards the center. The pushrod can be angled and bonded to fit into this shape. Note that this design may or may not tend to self-lock if the brake block moves to the right or left. This will also not be a directional brake block.

[0090] Example of a single pneumatic disc brake tappet with features simulating multiple tappets. As mentioned above, a single tappet can be used to reduce cost and complexity. However, unlike a dual-tappet brake where braking force is distributed on both sides of the backplate, the tappet in a single-tappet brake can contact a smaller surface area of ​​the backplate. Therefore, compared to using a dual-tappet brake, using a single-tappet brake may result in uneven distribution of braking force and consequently uneven wear of the inner brake pad. More specifically, when the rotor rotates, the leading edge of the inner brake pad may bear more applied pressure due to the uneven force distribution caused by the torque formed between the brake pad drag force and the support reaction force, thereby causing the leading edge of the inner brake pad to wear faster than the trailing edge. The tapered tappet design in the above embodiments can be used to partially or completely counteract this force to solve this problem.

[0091] In another embodiment (see...) Figure 15A and 15B A single strut 1500 is used, featuring raised features 1510, 1520 on plate 1505, which simulate multiple struts. (In one embodiment, the distance between the centers of the raised features 1510, 1520 is approximately 131 mm, but any suitable distance can be used.) This provides an "optimal compromise" design because the single strut 1500 reduces cost and complexity compared to a dual strut system, while the raised features 1510, 1520 provide at least some (if not all) of the force distribution benefits of a dual strut system. These raised features 1510, 1520 can distribute forces on the backplate, which can prevent the backplate and brake blocks from bending or being damaged, thereby avoiding the need to manufacture a very thick or robust (and therefore heavy) backplate resistant to bending or damage. In another embodiment ( Figure 15C and 15D As shown in the diagram, two pushers 1512 and 1514 are used. However, unlike the previous dual-pusher design, the outlines (outer edges) of the two pushers are bonded to at least a portion of the shape of the grooves 1410 and 1420 in the backplate. Various configurations and options (e.g., pusher size and shape, how the pushers fully or partially match the grooves, use (or non-use) tapers, etc.) can also be applied to this alternative.

[0092] These embodiments can be used alone or in combination with the interface features and / or tapered designs discussed above. For example, in Figure 15A and 15B In the embodiment shown, the protrusions 1510 and 1520 are circular in shape and match the corresponding grooves 1410 and 1420 in the back plate (the female grooves 1410 and 1420 in the back plate 1415 can also be used to receive the male tappet in a dual tappet braking system).

[0093] Similarly, as Figure 16AAs shown, the overall shape of the top of the tappet 1500 can be symmetrical, so a 180-degree rotation of the tappet 1500 can move the positions of the protruding features 1510, 1520 to opposite sides of the backplate 1415 to provide the versatility advantages discussed above (e.g., the tappet 1500 can be used for both left and right brakes). Figure 15A It is also shown that, in this embodiment, plate 1505 has various reinforcing ribs and features to strengthen and prevent deformation of plate 1505 and the inner brake block back plate 1415. However, in another embodiment ( Figure 16E and 16F As shown in the figure, instead of symmetrical protrusions, protrusions 2380 and 2390 are offset from the center 2392 of the push rod 2394 by different distances. In this example, the threaded tube is offset from the center 2392 of the push rod 2394, while in other examples, the threaded tube is the center 2392 of the push rod 2394.

[0094] Turn back Figure 16B The raised features 1510, 1520 can have different but uniform heights, with one raised feature 1510 being higher than the other raised feature 1520 (e.g., five millimeters higher). If each groove 1410, 1420 in the back plate 1415 has the same depth, the raised feature 1510 with the greater height will contact the back plate 1415 before the other raised feature 1520. This can provide a tilting action (similar to the tapered design discussed above) to provide a reaction force against forces generated by an uneven force distribution caused by a torque formed between the brake pad drag force and the support reaction force, which may cause uneven brake pad wear (e.g., controlling tapered brake pad wear by deviating from the pressure point (towards the trailing edge)). Alternatively, each groove 1410, 1420 in the back plate 1415 can have different depths to account for the different heights of the raised features 1510, 1520, which will provide an additional dimension to the mating interface features. Furthermore, in another embodiment (see... Figure 16D In the diagram, both raised features 1510 and 1520 are tapered.

[0095] In another embodiment ( Figure 16C As shown in the diagram, at least one of the raised features (here, raised feature 1510) may be tapered. In other embodiments, raised features 1510 and 1520 may both taper at the same or different angles (e.g., raised features 1510 and 1520 may both be at an angle relative to each other). There are many possible alternatives. For example, in Figure 17AIn this embodiment, the push rod 1700 has protruding features 1710 and 1720 on its plate 1705, but the protruding features 1710 and 1720 are octagonal rather than circular (the matching shapes 1610 and 1620 on the back plate 1615 are also octagonal). In another embodiment, the protruding features and the matching grooves have different geometries. For example, in Figure 17B In the middle, the strut 1900 has an octagonal protrusion 1910 and a circular protrusion 1920 on its plate 1922, which match the corresponding shapes 1810 and 1820 on the back plate 1815.

[0096] Similarly, as Figure 18A and 18B As shown, the groove 2025 in the backplate 2015 does not necessarily need to precisely match the geometry of the protrusions 2110 and 2120 on the plate 2105 of the strut 2100. Figure 18A and 18B In the example shown, the groove 2025 in the back plate 2015 is a large ellipse that contacts the left 180-degree portion of the left protrusion feature 2110 and the right 180-degree portion of the right protrusion feature 2120.

[0097] In another alternative, instead of a solid-shaped protrusion, other shapes of protrusions can be used. For example, in Figure 19A In the pusher 2200 shown, the two protruding features 2210 and 2220 on the plate 2205 are rings rather than solid circles / discs. As another example, in Figure 19B In the pushrod 2300 shown, the protruding features 2310-2326 are arc segments of a ring, not continuous rings. Of course, these are just examples, and other configurations can be used.

[0098] in conclusion It should be understood that all embodiments provided in this detailed description are merely examples, and other implementations may be used. For example, some features describing the interface between the tappet or tappet plate may be used in a single-tappet pneumatic disc brake or a multi-tappet pneumatic disc brake. Therefore, any components, architectures, or other details presented herein should not be interpreted into the claims unless expressly stated therein. Furthermore, it should be understood that components shown or described as being “connected” (or “connected”) to each other may be directly connected (or connected) to each other or indirectly connected (connected) to each other through one or more components that may not be shown or described herein. Additionally, “responsive to” can be directly or indirectly responsive to. Similarly, terms such as “generally,” “substantially,” or “about” may refer to a characteristic, parameter, or value that does not need to be precisely achieved, as deviations or variations may occur that do not impede the effect that the characteristic, parameter, or value is intended to provide (e.g., tolerances, measurement errors, measurement accuracy limitations, etc.).

[0099] The foregoing detailed description is intended to be understood as an illustration of alternative forms of the invention, and not a definition of the invention. Only the following claims, including all equivalents, are intended to define the scope of the claimed invention. Therefore, no component, architecture, or other detail presented herein should be interpreted into the claims unless expressly stated therein. Finally, it should be noted that any aspect of any embodiment described herein can be used alone or in combination with each other.

Claims

1. A pneumatic disc brake tappet comprising: a portion configured to couple the pneumatic disc brake tappet with a support member; and a plate coupled with a support member, wherein the plate comprises a plurality of raised features that simulate a plurality of pneumatic disc brake tappets.

2. The pneumatic disc brake tappet as defined in claim 1, wherein The plurality of raised features are shaped and positioned on the plate to match at least one feature of a brake pad backplate.

3. The pneumatic disc brake tappet as defined in claim 2, wherein, The at least one feature of the brake pad backplate comprises a plurality of features having the same shape as the plurality of raised features.

4. The pneumatic disc brake tappet of claim 2, wherein, The at least one feature of the brake pad backplate has a different shape than the plurality of raised features.

5. The pneumatic disc brake tappet of claim 1, wherein, The plurality of raised features comprise the same shape.

6. The pneumatic disc brake tappet of claim 1, wherein, The plurality of raised features comprise different shapes.

7. The pneumatic disc brake tappet of claim 1, wherein, At least one of the plurality of raised features comprises a solid shape.

8. The pneumatic disc brake tappet of claim 1, wherein, At least one of the plurality of raised features comprises a portion of a solid shape.

9. The pneumatic disc brake tappet of claim 1, wherein, The plurality of raised features have the same height.

10. The pneumatic disc brake tappet of claim 1, wherein, The plurality of raised features have different heights.

11. The pneumatic disc brake tappet of claim 1, wherein, At least one of the plurality of raised features is tapered.

12. The pneumatic disc brake tappet of claim 1, wherein, The plurality of raised features are all tapered at the same angle.

13. A pneumatic disc brake pad assembly comprising: a friction material; and a backplate coupled with the friction material, wherein the backplate comprises at least one groove shaped and positioned to receive a plurality of raised features of a pneumatic disc brake tappet, wherein the plurality of raised features simulate a plurality of pneumatic disc brake tappets.

14. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate comprises a plurality of grooves, each groove having the same shape as the plurality of raised features.

15. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate has a different shape than the plurality of raised features.

16. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate comprises a plurality of grooves, each groove having the same depth.

17. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate comprises a plurality of grooves, each groove having a different depth.

18. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate comprises a plurality of grooves, each groove having a different shape.

19. The air disc brake pad assembly of claim 13, wherein, The at least one groove in the backplate comprises a plurality of grooves, each groove having the same shape.

20. A pneumatic disc brake system comprising: a pneumatic disc brake pad comprising: a friction material; and a backplate coupled with the friction material, wherein the backplate comprises at least one groove; and a pneumatic disc brake tappet comprising: a support member; and a plate coupled with a support member, wherein the plate comprises a plurality of raised features that simulate a plurality of pneumatic disc brake tappets, wherein the plurality of raised features are shaped and positioned to match the at least one groove of the backplate.

21. The pneumatic disc brake system of claim 20, wherein, At least one of the plurality of raised features is tapered.

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