HK1209473B - Disc brake pad mounting and retention system and method - Google Patents

Description

Disc brake pad mount and retention system and method

Technical Field

The present invention relates to a disc brake for a vehicle, and in particular to a system and method of installing, removing and retaining brake pads in a disc brake, such as a pneumatic disc brake for a commercial vehicle.

Background

Pneumatic disc brakes have experienced development and application on commercial vehicles since at least the 70's of the 20 th century, and have begun replacing drum brakes due to advantages in areas such as cooling, fade resistance, and reliability of use. An example of such an air disc brake is disclosed in german patent application DE 4032886 a1, and in particular in fig. 1 of this document. In this design, a pneumatic diaphragm chamber (pneumatic actuator) is attached to the rear surface of the disc brake caliper housing and applies brake actuation forces to the brake actuator rod within the caliper via a linear actuator rod. The actuator rod of the brake in turn transmits and multiplies the force applied by the actuating rod to one or more shafts that force the brake pads against the brake disc or rotor. The terms "brake disc", "rotor" and "brake rotor" are used interchangeably herein.

As shown in fig. 1 of DE 4032886 a1, the actuator is mostly mounted on the brake caliper, because the size of the commercial vehicle rim only provides sufficient clearance for the drum brakes that were employed on such vehicles in the past. Because the production space enclosed between the wheel and its axle is limited, the actuator must be located in the space adjacent to the wheel. For the same reason, the brake pads must be configured to conform to the limited available radial space, and therefore have typically been positioned and retained on one of the brake caliper or brake caliper carrier/mount using lateral suspension pins and/or using leaf spring type metal strips configured over the entire outer diameter of the brake pads. The brake pads have been retained by capturing the brake pads between the caliper mount frame and the portion of the brake caliper straddling the brake disc. (As will be appreciated by those skilled in the art, the same brake pad support function may be provided by a brake caliper carrier/seat designed to support the brake pad or by a brake pad carrier separate from the caliper seat structure for ease of description, the terms caliper carrier, caliper seat and brake pad carrier may be interchanged without limiting the brake standard support structure to any particular brake pad and brake caliper carrying structure.)

Conventional commercial vehicle air disc brakes typically require the installation of an auxiliary brake pad retaining mechanism and/or the use of the brake caliper itself to retain the brake pad during operation. Both of these methods, and in particular the use of brake calipers as retaining devices, require disassembly of the brake pad retaining mechanism and/or removal of the brake caliper to replace worn brake pads and installation of new brake pads. Therefore, replacement of brake pads in previous air disc brake designs has been a labor intensive and therefore costly procedure.

A further problem with prior art brake pads is the tendency of the brake pad to rotate and/or vibrate during braking operations. As shown in fig. 6, when brake pad 101 is applied against a frictional surface of a brake disc (not shown) rotating in direction DR, the rotation of the brake disc causes movement and reaction forces between brake pad 101 and its adjacent pedestal abutment surface (not shown for clarity). Specifically, at leading edge 102 of brake pad, the brake pad attempts to move upward in direction LU in response to frictional forces along the surface of the brake pad (here represented by the arrow of force across the surface of brake pad 101). At the trailing edge 103 of the brake pad, the brake pad attempts to move downward in direction TD. However, because brake pad 101 is constrained by adjacent bed abutment surfaces, the overall movement of the brake pad rotates generally about an axis parallel to the rotor axis of rotation. This motion may be unilateral during brake application or may clearly indicate that the motion itself is a moderate to severe oscillation of the brake pad in its seat, significantly increasing wear against the brake pad and seat surfaces.

To prevent undesired rotation and/or vibration of the brake pad in its seat (e.g., rotation about a brake application direction), the brake pad backing plate and adjacent seat carrier horn need a relatively high radial height to minimize the amount of brake pad rotation (a motion known as "pad bounce" or "pad over-rotation") before the corners of the backing plate contact the adjacent frame horn, which supports the brake pad in a circumferential direction. This relatively tall structure, in turn, would require the brake caliper to have the radially outer opposing inner surfaces of its corresponding base horn trimmed sufficiently to accommodate the outer corners of the brake pad and/or base horn over which the brake caliper is mounted. The problems with this thinning are: because the maximum outer diameter of the brake caliper is typically bound to the inside of the adjacent rim with a very tight gap, the brake caliper arms that straddle the brake disc between the active and reaction sides of the caliper may eventually be thinner in this area than desired to accommodate the tall bracket mount horns and the tight fitting rim. This can result in very high tensile and bending stresses on the thin areas and undesirably reduce fatigue and service life.

Disclosure of Invention

The present invention addresses these and other problems by providing a brake pad mounting and retaining device and a method of installation and removal that more easily installs and removes brake pads in place without requiring brake caliper removal or other significant brake disassembly work. This solution is significantly more space constrained commercial vehicle air disc brake applications where the brake pads operate without requiring significant brake disassembly of the operating caliper, which has not previously been believed to be commercially viable.

In one embodiment of the invention, the brake caliper mount brake pad support horn is provided with a narrow vertical groove or slot in the side of the horn facing the opposite side from the brake disc. The groove is arranged to allow the brake pad to slide downwards along the groove in a radially inward direction until the brake pad reaches a mounting position, the brake pad having features of corresponding thickness at its lateral sides. The horn further has at or near its base a transverse groove extending parallel to the axis of rotation of the brake disc, the transverse groove being arranged to receive a side member of the brake pad so that the brake pad may advance towards the brake disc when pushed forward by an actuator of the brake caliper. During use, the brake pads are positively retained in the brake by a combination of: (i) a lateral groove in the base horn that prevents lift of the brake pad from the caliper and over-rotation of the brake pad (i.e., twisting or "flipping" of the brake pad in the caliper when the rotating brake disc attempts to raise one end of the brake pad while the other end of the brake pad is pushed downward); (ii) a brake disk that prevents the brake pad from advancing too far to escape from the base horn lateral groove; and (iii) by brake application means which prevents the brake pads from retracting too far back to reach the base horn vertical groove and slide out of the top of the caliper.

This arrangement also facilitates easy and quick brake pad changes, as all that is required to remove the brake pads after the wheel is removed to fully withdraw the brake application device is to axially slide the brake pad backing plate to reach the pedestal horn vertical groove and then simply lift the brake pads from the opening in the top of the brake caliper still in the installed state. A new brake pad may then be inserted into the vertical groove until the lateral member of the backing plate is aligned with the lateral groove, followed by advancing the brake application device behind the brake pad a sufficient distance to prevent it from exiting the lateral groove.

The present invention also provides the ability to significantly reduce the height of the base horn, thus allowing the brake caliper thickness in high stress areas to be made thicker to increase strength and caliper life. The relatively compact grooves and corresponding engagement feature geometry on the brake pad backing plate ensure that the amount of brake pad rotation within the carrier is significantly limited relative to prior art arrangements. Thus, the horn can be made shorter because it is no longer necessary to provide a relatively tall base horn to limit brake pad rotation (since the groove now limits brake pad rotation). With respect to the reduction in horn height, the additional clearance newly established between the horn and the inner surface of the brake caliper in the entire area of the horn allows the caliper to be made thicker in these high load areas. The addition of caliper material in these areas provides additional load loading cross-sectional area, and a reduction in response to local stress levels and an increase in caliper fatigue life.

Preferably the brake pads, the base and/or the brake caliper may be provided with vibration damping means such as spring loaded brackets on the lateral extension of the backing plate or spring member engaging lugs on the upper surface of the backing plate and the caliper or on the caliper base.

Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.

Drawings

Fig. 1 is an oblique view of a disc brake according to an embodiment of the present invention.

FIG. 2 is an oblique view of the caliper mount bracket and brake pad of FIG. 1.

Fig. 3a, 3b and 3c are side, front and top views, respectively, of the brake pad of fig. 1 and 2. Fig. 3d is a detailed view of the embodiment of the brake pad retaining feature shown in fig. 3 b.

Fig. 4a and 4b are a front view and a front view, respectively, of the caliper mount bracket of fig. 1 and 2. Fig. 4c is a cross-sectional view of the caliper mount bracket of fig. 1 and 2 showing an embodiment of a brake pad guiding and retaining groove of the mount horn.

Fig. 5 is a detailed view of a brake pad retaining feature including a preload device according to an embodiment of the invention.

FIG. 6 is a simplified illustration of the motion and forces resulting from application of a brake pad to a rotating brake disc.

Fig. 7a and 7b are views of an alternative embodiment of a brake pad having brake pad retaining features on a lower surface of the brake pad.

Fig. 8a and 8b are views of an alternative embodiment of a brake pad having asymmetric and rotationally adjusted brake pad retaining features.

Detailed Description

In the embodiment shown in fig. 1, a disc brake 1 for a commercial vehicle comprises a brake disc 2, a brake caliper 3, which brake caliper 3 straddles the brake disc 2. The caliper 3 is typically attached via a torque plate or brake frame (not shown) to a caliper mount bracket 4, which caliper mount bracket 4 is in turn fixed to the vehicle axle. The caliper 3 is actuated by an actuator 5, in this embodiment a spring brake actuator, which is controlled by the pneumatic pressure of the vehicle. The actuator 5 acts on a brake pad application mechanism contained within the caliper 3 to press the brake pads 6 against the brake disc 2 to decelerate the vehicle. The invention is not limited to pneumatic actuators (e.g., electrically driven actuators may be used) or to particular types of brake caliper/base arrangements (e.g., fixed bracket and sliding caliper with a single-sided brake pad application mechanism, or fixed bracket and fixed caliper with a two-sided brake pad application mechanism). In this embodiment, the caliper 3 is provided with holes 7, which holes 7 are wide enough in the circumferential direction a and the axial direction B to allow the brake pads 6 to be withdrawn and inserted without removing the caliper 3 from the carrier mount 4.

Fig. 2 illustrates an oblique view of the carrier and brake application side brake pad of fig. 1, with the brake disc 2, caliper 3, actuator 5 and opposing brake pad 6 removed for clarity. In this view and fig. 4a-4c, there is illustrated a hole 8 in the base 4, the hole 8 for receiving a caliper and axle mounting bolt, and a lateral brake pad engagement surface 9 on a base horn 10. It will be appreciated that the carrier need not be a caliper support carrier, i.e. the caliper may be mounted on a separate component from the carrier and only the brake pads are supported by the carrier.

In this embodiment each base horn 10 has a vertical brake pad installation/removal groove 11 and a horizontal brake pad guiding groove 12 at the bottom of each base horn 10. It will be appreciated that the grooves or slits need not be located at the axial position on the carrier base 4 furthest from the brake disc 2, or precisely at the bottom of the base horn 10, as long as the brake pads 6 used in the brake are prevented from coming off the carrier base 4 during use and have pad retaining features with a vertical height corresponding to the height of the horizontal grooves 12. In an alternative embodiment, the vertical mounting/removal groove 11 may be omitted, as long as in the direction of the brake disc rotation axis, sufficient space is provided in the caliper hole to allow the brake pads to be inserted radially inward into the brake so that the retaining features of the brake pads can reach and enter the horizontal groove 12.

Fig. 2 and 3a-3d show a brake pad 6 comprising: a brake pad backing plate 14 and brake pad material 15, the brake pad material 15 being attached to the brake pad side of the brake pad 6. The brake pad material 15 is arranged to fit between the base horns 10 without engaging with the grooves 11 or 12 to ensure free movement towards and away from the brake disc 2 and vertically into and out of the caliper during brake pad installation or removal. The brake pad 6 is also provided with a pad holding member 16 at a lower corner portion on the lateral side of the backing plate 14. In the present embodiment, the retaining members 16 are arranged as lug-like extensions of the back plate 14. Preferably, the lugs have a thickness in the brake application direction that corresponds to the thickness of the backing plate 14, so that no special machining or other shaping for width reduction is required. Regardless of the thickness of the brake pad retaining feature 16, the vertical groove 11 must have an axial thickness and circumferential width large enough to accommodate the vertical channel of the brake pad retaining feature 16 during insertion and removal of the brake pad 6. Similarly, the transverse or axial groove 12 must have a vertical height and circumferential width large enough to accommodate the horizontal channel of the pad retaining feature 16 during brake application and release in use and during removal of the brake pad 6 away from the brake rotor 2. Preferably, the transverse groove 12 is located radially inwards towards the caliper mount 4, where the bracket is more rigid.

In addition to the preferred arrangement of having male brake pad retaining features extending laterally into female lateral receiving grooves, the female slits in the lateral sides of the brake pad backing plate may be arranged to receive corresponding male projections projecting from the caliper mount after insertion of the brake pad into the disc brake along the radially positioned grooves. Alternatively, the female lateral receiving groove can be placed directly on the caliper body, with or without a corresponding part on the caliper mount. Additional example brake pad retaining feature arrangements are discussed further below.

Also visible in fig. 3b and 3c is a groove 18 on the brake pad 6 for receiving a pad wear indication sensor (not shown).

Fig. 3d shows a detailed view of the area of the brake pad 6 highlighted in area C of fig. 3 b. In this region, the brake pad retaining feature 16 is provided with a beveled edge, chamfer or rounded profile 19 at its lower edge to facilitate interference-free insertion and removal of the brake pad and to avoid contact points between the retaining feature 16 and the carrier base 4 that create pressure concentrations within the groove 12. Preferably, corresponding mating features are provided on the bracket to reduce stress concentrations. The brake pad retaining feature 16 is also provided with a beveled edge 20, preferably at an angle corresponding to the same angle at the top of the horizontal groove 12. The upper inclined edge 20 is arranged to present a larger bearing surface and thus a lower contact pressure and stress when braking forces are transferred from the brake pads 6 to the carrier base 4 during brake application, i.e. when the brake pads 6 are driven in rotation in the carrier base 4 by the brake disc 2. The inclusion of the beveled edge 20 provides a flat surface to absorb forces over a wide contact area to minimize component wear, thus preferably avoiding point or edge contact between the brake pad 6 and the carrier base 4, which may occur on opposing linear surfaces.

The angle of the beveled edge may be set to ensure that the contact pressure generated during maximum brake pad loading is below the yield strength of the brake pad backing plate and carrier base material. If the load being supported during brake application is relatively low, a shallow bevel angle of about 95-110 degrees may be sufficient to provide sufficient contact area at the top of the bevel so that the stress level (force/area) is below the yield strength of the assembly. At higher loads or with lower yield strength materials, a larger angle of about 110-165 degrees is required to provide a sufficiently large contact area for load distribution to remain below the yield strength limit. At an angle between 140-160 degrees, preferably 150 degrees, a large contact area is provided while still minimizing the amount of brake pad "lift" or rotation during brake application.

The significant benefits of the brake pad retaining arrangement of the present invention are apparent in this embodiment. In the prior art, due to the need to maintain at least a minimum gap between the flat opposing faces of the brake pad of conventional linear edges and their opposing pedestal horn abutment surfaces, the pedestal horn and the brake pad mounting plate face must be relatively high to minimize the extent to which the brake pad can rotate about the axis direction B when the brake is applied. With the current state of the art, due to the distance between the diagonally opposed corners of the brake pad, unless a high base horn is provided to minimize the angular displacement of the brake pad, the typical tolerances between the brake pad backing plate and the base horn will result in a relatively large degree of undesired rotation of the brake pad within the base. In the present invention, because the retaining feature interacts with the relatively small horizontal groove 12, even with the same minimum brake pad/foot horn clearance requirements as in conventional prior brakes, the brake pad 6 does not rotate as much as a conventional brake pad before the upper surface of the brake pad retaining feature 16 contacts the top of the horizontal groove 12 and stops the angular displacement of the brake pad 6.

For example, a typical prior art brake pad and retaining device would allow approximately 4 millimeters of movement, which results in large displacement vibrations and accelerated wear of the abutment surfaces of the brake pad backing plate and the base horn. For the present invention, these movements can be reduced by more than 75%. Experiments with the sample configuration have shown that the movement is limited to only 0.75 mm. Thus, because the brake pad rotation maneuver has been transferred from the top edge of the base horn to the horizontal groove 12, the base horn need not be as tall as previously known to control brake pad rotation to a desired extent. This in turn allows avoiding undesirable thinning of the brake caliper in the region above the top of the base horn, thus allowing these very high loads and stress regions to have a larger cross-sectional area to absorb these loads. Despite the very constrained rim environment of commercial vehicles, less stress directly corresponds to increased caliper strength and increased caliper fatigue life. The increase in the stress-bearing volume of the material also makes it possible to replace the expensive special alloys used to obtain sufficient strength in the thin portions of the caliper with ordinary cast iron, significantly reducing the material and production costs. It should be noted that while the amount of "brake pad bounce" may be low in the present invention, when the brake pad retaining feature and corresponding lateral groove chamfer angle is selected, the angle may be slightly different to accommodate brake pad rotation during braking, i.e., the brake pad retaining feature angle may be slightly more obtuse than the angle of the lateral groove chamfer of the base, such that the contact surface causes contact across a planar area as the brake pad rotates in the base rather than just a single line contact.

A further advantage of the present invention is to allow for the omission of retaining leaf spring interlock components on top of the brake pad backing plate, and associated structure in the radial direction above the brake pad for receiving and retaining the leaf spring (e.g., brake pad hold down bar), thus increasing the radial clearance above the brake pad and possibly allowing for a reduction in the maximum radial extent of the caliper within the wheel envelope or allowing for an increase in the diameter of the brake disc and the height of the brake pad to increase the size of the brake swept area in which the brake pad material interacts with the brake disc surface.

Brake pad retaining features of the present invention may also be provided with spring elements at or near the brake pad retaining feature to preload or dampen the brake pad as desired relative to the base to reduce brake pad movement and reduce vibration, which may cause undesirable noise and component wear during brake application. Fig. 5 shows a detailed view of an example arrangement in which spring elements 22 are located between brake pad retaining feature 16 of brake pad backing plate 14 and the outer wall of lateral groove 12. Such a pre-load element may be attached to the base plate 4 or the brake pad backing plate 14, for example by riveting or clamping, or may be a separate element that is inserted between the base plate 4 and the brake plate 14 when the brake pad 6 is inserted into the brake. Alternatively, the preload element may have any of a number of suitable arrangements, such as a hinge member provided with a spring element biasing the hinge member laterally outwardly to engage the opposed surfaces.

A further embodiment of the invention is illustrated in fig. 7a-7 b. In this embodiment, brake pad retention is achieved using lugs 16 on the lower edge or surface of the brake pad backing plate 14 and undercut grooves on at least one lateral side of the lugs that engage with corresponding undercut grooves in the horizontal receiving grooves 12. In this embodiment, the groove 12 is machined into the lower surface of the caliper mount adjacent the vehicle brake pad abutment 10, rather than laterally across the surface of the abutment. As in the example embodiment described above, this bottom lug embodiment is inserted vertically (i.e., radially inward) along the outside of the abutment 10, and then advanced toward the brake disk into engagement with the groove 12 to positively retain the brake pad.

Fig. 8a and 8b illustrate another embodiment of the present invention, wherein the brake pad retaining feature is asymmetric and is also configured to accommodate brake pad rotation by the brake disc with minimal pad movement and minimal pad, abutting surface wear. Fig. 8a illustrates brake pad backing plate 14 having beveled edge lugs 16 on the leading edge side of the brake pad and curved lugs 16A on the trailing edge side of the brake pad. This configuration provides a number of further advantages, including a configuration that inherently prevents the brake pad from being mounted on the wrong face of the brake disc due to the incompatibility of the corresponding grooves 12 in which the brake pad slides. The curved surfaces and correspondingly the grooves 12 also form a bearing arrangement like a "ball and socket" or "cylinder-and-socket", thus providing a wide surface area for contact between the brake pad lugs 16A and the grooves 12, which will reduce interface stresses and resulting component wear. The curved surface may also further reduce the amount of brake pad movement ("brake pad bounce") by more tightly limiting the range of motion of the trailing edge of the brake pad, with the curved lugs 16A acting as a rotational approximate fixation point about which leading edge lugs 16 rotate. This near fixed trailing edge configuration, essentially acting as a pivot, also provides additional resistance against brake pad movement that may become too large to cause large amplitude vibrations.

As shown in fig. 8B, trailing edge lobe 16B may be a large radius curve, further spreading the reaction force load over a wider contact area. The curvature of the trailing edge lugs is not limited to a constant radius curve. For example, the curve may be configured to have a decreasing or increasing radius to further define movement of the trailing edge of the brake pad, e.g., during brake application. Alternatively, the curve may be a polygonal shape. As in all embodiments of the invention, these shapes may be economically formed, for example by machining the groove 12 transversely across the face of the seat abutment surface with a suitable tool.

As in the previous embodiments, the rotation of the brake pad in braking in the brake pad backing plate design and/or the base arrangement may preferably be explained. For example, the curved retention feature is on the trailing edge of the brake pad to accommodate "lift" of the leading edge of the brake pad during brake application (since the retention feature of the leading edge occupies clearance in the lateral groove when the beveled edge surface contacts the top of the beveled edge of the lateral groove), it is desirable to provide a very corresponding very small relief angle or tapered horn on the straight portion of the trailing edge of the brake pad. The amount of clearance in the leading edge lateral groove preferably remains large enough to ensure free pad movement toward or away from the brake disc under all operating conditions, but small enough to rotate only under about three degrees as the pad rotates about the curved retaining feature on the trailing edge (i.e., the trailing edge clearance angle will be less than about 10 degrees and preferably will remain under three degrees, preferably about one degree).

The time and effort saving method of brake pad installation in the new brake embodiment of the invention will comprise a first step: the brake caliper, which is still devoid of brake pads, is slid axially outwardly to position the brake in a position for receipt of the brake pads externally. The second step will include: the brake pads are inserted radially inward on the outside until the lateral retaining features of the brake pads are aligned with the lateral receiving features on the outside of the brake pad carrier. The third step will include: the caliper is slid in an axially inward direction to advance the outer brake pads into engagement with the outer brake pad receiving features of the carrier and to position the caliper for receiving the inner brake pads. The fourth step will include: the brake pads are inserted radially inward of the interior until lateral retaining features of the brake pads are aligned with lateral receiving features on the interior side of the brake pad carrier. The fifth step will include: the brake application or adjustment mechanism is advanced in a brake application direction to advance the inner brake pads into engagement with the inboard brake pad receiving features of the carrier and to position the caliper for brake operation. The thickness of the brake pad retaining feature and the arrangement of the corresponding receiving feature must be: even if the brake pads and brake rotor are new, i.e. their maximum thickness before use, it is always ensured that sufficient brake pads remain engaged.

In case of a brake pad replacement, for example in a brake in use, the above brake pad loading method will start with a corresponding brake pad removal operation, wherein: the brake application and/or adjustment mechanism is withdrawn far enough to allow the inner brake pad to move away from the brake disc to reach a brake pad removal position, the inner brake pad will be withdrawn radially outward through the caliper aperture, the caliper will move far enough in a radially outward direction to allow the outer brake pad to move away from the brake disc to reach its brake pad removal position, and the outer brake pad will be withdrawn radially outward through the caliper aperture.

The foregoing disclosure is illustrative of the present invention only and is not intended to be limiting thereof. For example, in addition to machining the vertical and lateral grooves 11, 12 in the base horn 10, alternative brake pad abutment surfaces may be provided on the carrier base 4, the width and height of which correspond to the geometry of the retaining features on the brake pad backing plate 14. As another example, more than one brake pad retaining feature and corresponding receiving feature on the caliper may be provided on each of the lateral sides of the brake pad, and/or the features may be provided at different heights. Since other such modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and their equivalents.

Claims (9)

1. A disc brake (1), characterized by comprising:

a brake disc (2);

a brake caliper (3) arranged astride of the brake disc (2);

a brake caliper mount (4) arranged to receive a brake caliper (3); and

a brake pad (6);

wherein the content of the first and second substances,

the brake caliper mount (4) comprising a brake pad abutment (10), the brake pad abutment (10) being arranged to limit movement of the brake pad (6) in a circumferential direction of the brake disc (2), the brake pad abutment (10) comprising at least one radially oriented brake pad insertion feature (11), the radially oriented brake pad insertion feature (11) being formed as a substantially radially oriented groove extending parallel to an adjoining lateral side of the brake pad (6), and a radially inward end of the groove (11) being in contact with at least one lateral brake pad receiving feature (12) at an end thereof axially remote from the brake disc, the at least one lateral brake pad receiving feature (12) being oriented parallel to an axis of rotation of the brake disc (2);

the brake caliper (3) comprises: a brake pad opening (7), the brake pad opening (7) being sufficiently wide in the circumferential direction of the brake disc (2) to allow the brake pad (6) to pass through the caliper (3) into the at least one radially oriented brake pad insertion feature (11) without removing the caliper (3) from the caliper mount (4);

the brake pad (6) comprises at least one pad retaining feature (16) corresponding to the at least one lateral brake pad receiving feature (12) of the caliper mount (4); and is

The at least one radially oriented brake pad insertion feature (11) and the at least one lateral brake pad receiving feature (12) are arranged to allow the brake pad (6) to move radially in the at least one radially oriented brake pad insertion feature (11) while parallel to a friction surface of the brake disc (2) when the brake pad (6) is aligned with the at least one radially oriented brake pad insertion feature (11) and to allow the brake pad (6) to move axially toward or away from the brake disc (2) while being held within the disc brake (1) by the at least one lateral brake pad receiving feature (12) when the brake caliper (3) is in an operable position.

2. The disc brake (1) according to claim 1, characterised in that wherein

The brake application device of the brake caliper (3) is configured to prevent alignment of the brake pad (6) with the at least one generally radially oriented brake pad insertion feature (11) when the brake application device is advanced toward the brake disc (2).

3. The disc brake (1) according to claim 2, characterised in that wherein

The brake application device is configured to allow the brake pad (6) to move in a radially inward or radially outward direction via the at least one radially oriented brake pad insertion feature (11) when the brake application device is withdrawn a sufficient distance from the brake disc (2).

4. The disc brake (1) according to claim 1, characterised in that wherein

The at least one pad retaining feature (16) of the brake pad (6) has a radially outward upper surface (20) arranged at a non-perpendicular angle to a side surface of the brake pad (6).

5. The disc brake (1) according to claim 4, characterized in that wherein

The non-perpendicular angle of the at least one pad retaining feature (16) of the brake pad (6) is an obtuse angle.

6. The disc brake (1) according to claim 4, characterized in that wherein

The at least one pad retaining feature (16) of the brake pad (6) and the at least one lateral brake pad receiving feature (12) of the caliper mount (4) have complementary surfaces (20) arranged at a non-perpendicular angle to provide non-point contact between the at least one pad retaining feature (16) and the at least one lateral brake pad receiving feature (12) of the brake pad (6).

7. The disc brake (1) according to claim 6, characterized in that wherein

The non-point contact is one of a linear or planar contact.

8. The disc brake (1) according to claim 1, characterised in that wherein

The brake pad abutment portion (10) of the brake caliper mount (4) is bridged by a connecting bridge portion on a side of the disc brake (1) opposite to a side of the caliper having a brake actuating portion, and

the side of the connecting bridge facing the brake disc (2) is arranged not to interfere with the radial insertion of the brake pad along the at least one radially oriented brake pad insertion feature (11).

9. The disc brake (1) according to claim 1, characterised in that wherein

The brake pad abutment (10) and the at least one lateral brake pad receiving feature (12) of the brake caliper mount (4) are arranged such that braking forces applied to the brake pad (6) in the circumferential direction of the brake disc (2) during brake application are transmitted to the brake pad abutment (10) only through the at least one brake pad retaining feature (16) of the brake pad (6) and at least one of the abutting lateral sides of the brake pad (6).