Brake calliper

Abstract

A brake calliper comprising an inner shell and an outer shell coupled together to define a cavity for receiving a plurality of brake pads arranged in a spaced apart relationship with respect to each other defining at least one spacing for receiving a rotor, the inner shell comprising a body having an inner surface for abutment of one brake pad and an outer surface for receiving hydraulic fluid from a hydraulic circuit, the inner surface having at least one indentation for receiving a piston having a head for receiving the hydraulic fluid and a distal end to actuate the brake pad, and the outer surface defining a hydraulic path for delivery of the hydraulic fluid to the head of the piston, the indentation comprises a side wall for surrounding of the piston, and an end area for receiving the head of the piston, wherein the end area comprises an undercut extending into the side wall of the indentation for receiving the hydraulic fluid.

Description

Brake CalliperTECHNICAL FIELD

[0001] The present invention relates to a disc brake system for vehicles, in particular heavy duty vehicles.

[0002] The invention has been devised particularly, although not necessarily solely, in relation to brake calliper systems, in particular the system used for delivery of the hydraulic fluids for actuation of the pistons for moving the brake pads.BACKGROUND ART

[0003] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

[0004] For operation of brake systems of vehicles, the callipers of the brake systems are provided with hydraulic fluid to actuate pistons for moving of brake pads with the intention to reduce the speed of the vehicle including the brake system.

[0005] As will be described hereinafter with reference to figures 1 to 3, the calliper include cylinders (containing the pistons) provided with inlets allowing connection of pipes for delivery of the hydraulic fluid into the cylinders to apply force to the pistons for movement thereof.

[0006] Figures 1 , 2, 3a and 3b show, respectively, a section view of a conventional brake system mounted on an axle 16, a prior art calliper 14, the cross-sectional view along the line 3a-3a of the calliper 12 shown in figure 2, and the detail A of the section shown in figure 3a, depicting a cylinder 114 including a piston 120.

[0007] The brake system 10 comprises a housing assembly 12 and brake callipers 14. A rotor 20 is splined onto and thus rotates with the hub 18. A portion of the brake callipers 14, and in particular cylinders 22 of the brake callipers 14, extend into and are seated in openings 24 formed in the housing assembly 12.

[0008] The brake system 10 comprises three similar but different callipers 14. Figures 2 and 3 are representations of the park / service calliper 14a.

[0009] The park / service brake calliper 14a comprises an inner shell 104 and outer shell 106 which are coupled together to define a cavity 108 in which the rotor 20 rotates and which houses opposing brake pads 110a and 1 10b (shown in Figure 1 ). The cavity 108 opens onto an outer circumferential surface 109 of the calliper 14a forming a central gap 111 between the shells 104 and 106. The brake pad 1 10a is seated in a recess 112 formed on an inside of the outer shell 106. The inner shell 104 is formed with three cylinders 114a, 114b and 114c (hereinafter referred to in general as "cylinders 114"). Each of the cylinders 114a and 114c is provided with inlets 118 to allow connection to pipes providing hydraulic fluid to respective service brake pistons 120 retained in the cylinders 1 14a and 1 14c. Extending transversely between the inlets 118 on each cylinder 114a and 1 14c is a land 122 to facilitate connection of a spring canister 124 (shown in Figure 1 ). The spring canister is pneumatically operated to provide the park brake aspect of the service / park brake calliper 114a.

[0010] In conventional callipers, the hydraulic fluid is delivered into the cylinders via inlets having their outlets in fluid communication with the area of the cylinders surrounded by the side wall of the cylinder including the piston. This can be seen in figures 3a ad 3b depicting a prior art calliper. As shown best in figure 3b, the outlets of the inlets are within the circumference defined by the side wall of the cylinder. Also, due to the particular configuration of the cylinders of the callipers, the hydraulic fluid delivered to the cylinders is confined within the circumference defined by the side wall of the cylinder.

[0011] The drawback of the hydraulic fluid being confined within the circumference defined by the side wall of the cylinder is that it is difficult to know where the highest point of the hydraulic circuit actually is. Thus, accurately locating the bleeding nipple at the highest point of the hydraulic circuit is difficult resulting in that the bleeding nipple may not be located at the highest point of the hydraulic circuit. This results in that all air (that may be contained within the hydraulic chamber adjacent the head of the piston) will not be fully purged from the hydraulic circuit due to the bleeding nipple not being located at the highest point of the hydraulic circuit. Also, in conventional brake systems the presence of the bleed nipple and / or the pipe nipple prevents fitting of the brake system not to allvehicles applicable to receive such brake systems as well as locating of other parts adjacent the brake system.

[0012] In order to guarantee that all air is completely purged out of the cylinder, the bleeding outlet needs to be located at the highest point of the hydraulic circuit. Any air left over in the cylinder may compromise proper working of the braking system, thus potentially resulting in undesirable consequences.

[0013] It is against this background that the present invention has been developed.SUMMARY OF INVENTION

[0014] According to a first aspect of the invention there is provided a brake calliper comprising an inner shell and an outer shell coupled together to define a cavity for receiving a plurality of brake pads arranged in a spaced apart relationship with respect to each other defining at least one spacing for receiving a rotor, the inner shell comprising a body having an inner surface for abutment of one brake pad and an outer surface for receiving hydraulic fluid from a hydraulic circuit, the inner surface having at least one indentation for receiving a piston having a head for receiving the hydraulic fluid and a distal end to actuate the brake pad, and the outer surface defining a hydraulic path for delivery of the hydraulic fluid to the head of the piston, the indentation comprises a side wall for surrounding of the piston, and an end area for receiving the head of the piston, wherein the end area comprises an undercut extending into the side wall of the indentation for receiving the hydraulic fluid.

[0015] Preferably, the undercut comprises one or more recesses extending into the side wall of the indentation.

[0016] Preferably, the indentation defines a cylinder for receiving the piston.

[0017] Preferably, the outer surface of the inner shell comprises at least one opening for receiving the hydraulic and / or bleeding the hydraulic circuit.

[0018] Preferably, the opening is adapted for receiving a nozzle having either a fixture for receiving piping to deliver the hydraulic fluid into the indentation or a bleeding nipple or balance nipple.

[0019] Preferably, the recess is adapted to be fluidly connected to the opening for delivering brake fluid into the indentation or bleeding of the hydraulic circuit receiving the piston.

[0020] Preferably, the recess(es) is / are configured in order to offset the opening for receiving the hydraulic fluid or the bleed and / or balance nipple with respect to the circumference of the inner end of the indentation receiving the piston.

[0021] Preferably, at least one of the recesses extend a particular distance into the side wall of the indentation, the particular distance being such that a spacing is defined at a particular location about the longitudinal axis of the indentation.

[0022] Preferably, the spacing is located at the highest point of the hydraulic circuit for receiving any air contained in the hydraulic circuit.

[0023] Preferably, the spacing is located at a location which permits fitting a brake system comprising the brake calliper to different type of vehicles.

[0024] In an arrangement, the undercut may be configured in such a manner that the bleed nipple and / or the balance nipple and / or opening for receiving the hydraulic circuit may be located at particular locations allowing fitting the brake system at particular orientations to accommodate packaging constrains. For example, for fitting the brake system to vehicles using leaf springs (such as the VOLVO® FMX trucks) the

[0025] Preferably, the inner shell comprises a body having an outer surface into which at least one opening extends to define the hydraulic fluid path ending in the indentation, and an inner surface for abutment of the brake pad permitting actuating the piston when the hydraulic fluid is delivered into the indentation through the inlet, wherein the opening is fluidly connected to at least one of the recesses.

[0026] Optionally, the one recess indents into and around the entire inner periphery of the side wall of the indentation.

[0027] In an arrangement, there are one or more recesses indenting into particular locations of the periphery of the side wall.

[0028] In an arrangement, there are at least three brake pads and two rotors, the two rotors being arranged in a spaced apart relationship with respect to each other defining a spacing for receiving one or more brake pads, and one spacing being defined between one rotor and the inner surface of the inner shell for receiving a brake pad, and another spacing being defined between one rotor and the inner surface of the outer shell for receiving a brake pad.

[0029] In an alternative arrangement, the inner and outer shell are coupled together defining a cavity for receiving two brake pads arranged in a spaced apart relationship with respect to each other defining a spacing for receiving a rotor.

[0030] According to a second aspect of the invention there is provided a brake system comprising at least one brake calliper in accordance with the first aspect of the invention.

[0031] According to a third aspect of the invention there is provided a method for locating the bleeding nipple at the highest point of the hydraulic circuit of a brake system of a vehicle, the method comprises the step of installing a brake system comprising a calliper in accordance with the first aspect of the invention in the vehicle, orienting the braking system such that the spacing to be fluidly connected to the bleeding nipple is located at the highest point of the hydraulic fluid.

[0032] Preferably, the method furhter comprises the step of fluidly connecting the bleeding nipple to the spacing located at the highest point of the hydraulic circuit.

[0033] According to a fourth aspect of the invention there is provided a method for installing a brake system comprising a calliper in accordance with the first aspect of the invention in a vehicle, the method comprising the step of orienting the brake system such that the spacing of the undercut can be accessed for machining the openings in the outer surface of the inner shell of the calliper for receiving the hydraulic fluid and / or the bleeding nipple.

[0034] Preferably, the methods further comprises the step of machining the recess prior installation of the brake calliper for improving the bleeding process or fitting the brake system to different type of vehicles.BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Further features of the present invention are more fully described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. The description will be made with reference to the accompanying drawings in which:Figure 1 shows a cross-sectional view of a prior art brake system mounted on an axle showing the cross-sectional views along the line 1 -1 of the callipers shown in figure 2;Figure 2 shows a perspective view of a prior art calliper included in the brake system shown in figure 1 ;Figure 3a shows a cross-sectional view of the calliper shown in figure 2 along the line 3a-3a;Figure 3b shows detail A of the calliper shown in figure 3a;Figure 4 shows a plan view of a particular arrangement of a brake system in accordance with the present embodiment of the invention;Figure 5 is a rear view of the brake system shown in figure 4 with the housing removed;Figure 6 is a cross-sectional view along the line 6-6 of the brake system shown in figure 4;Figure 7 is a side view of the brake system shown in figure 4 attached to a vehicle axle;Figure 8 is a cross-sectional view along the line 8-8 of the brake system shown in figure 7;Figure 9 is a cross-sectional view along the line 9-9 of a particular arrangement of a caliper in accordance with the present embodiment of the invention incorporated in a housing assembly 20 as shown in figure 8;Figure 10 shows detail B shown in figure 9 incorporating the piston and balance nipple and bleed nipple;Figure 11 is a cross-sectional view along the line 11 -11 of the brake system shown in figure 10;Figure 12 shows detail C shown in figure 9; andFigure 13 is a cross-sectional view of the brake system shown in figure 4.DESCRIPTION OF EMBODIMENT(S)

[0036] Figures 4 to 13 show a particular arrangement of a brake system 200 in accordance with an embodiment of the invention.

[0037] As shown in figure 13, the brake system 200 comprises a housing assembly 201 and brake callipers 202a and 202b inserted into the housing assembly 201 - see figure 8.

[0038] Each calliper 202 comprises an inner shell 207a and an outer shell 207b. The inner shell 207a and outer shell 207b are spaced apart with respect to each other defining a spacing for receiving three brake pads 218a, 218b and 218c, and two rotors 203a and 203b. The plurality of rotors 203 rotate with the hub 205.

[0039] The inner shell 207a comprises an outer surface 224 comprising at least one openings for receiving the hydraulic fluid and a bleeding nipple 213, wherein the openings are adapted for receiving nozzles 212 having either a fixture for receiving piping to deliver the hydraulic fluid into one or more cylinders 214, or a bleeding nipple 213 and / or balance nipple 215.

[0040] Each brake calliper 202 extend into and are seated in indentations formed in the housing assembly 201 as shown in figure 8.

[0041] In the particular arrangement shown in figure 13, there are a pair of rotors 203a and 203b arranged in a spaced apart relationship with respect to each other defining a spacing between for receiving an inner brake pad 218c. Another spacing is defined between the rotor 203a and the inner surface 226 of the inner shell 207a for receiving a brake pad 218a. A further spacing is defined between one rotor 203b and the inner surface 227 of the outer shell 207b for receiving a brake pad 218b.

[0042] As will be described hereinafter, particular arrangements of the callipers 202, in accordance with the present embodiment of the invention, are configured for, for example, enhancing the bleeding process to ensure all air that may be contained within the hydraulic circuit (carrying the hydraulic fluid for operation of the brake system 200) has been purged out of the hydraulic circuit. In particular, an undercut 232 (see figure 12) is defined ensuring that any air (in the hydraulic circuit) is always located at the highest point of the hydraulic circuit of the brake system. The undercut 232 is defined adjacent the head 209 of the piston 211 .

[0043] Alternatively, the undercut 232 may be configured so that the brake system 200 may be installed in a relatively large number of different type of vehicles.

[0044] In particular arrangements, the undercut 232 can take different shapes and configurations in order to offset a bleed nipple 213 and / or balance nipple 215 (see figure 10) and / or opening(s) for receiving the hydraulic fluid with respect to the circumference defined by the inner end of the cylinder 214. Offsetting the openings for receiving the bleed nipple 213 and / or the balance nipple 215 or openings for receiving the hydraulic fluid permitting locating the openings at locations to improve the bleeding process and / or allowing fitting of the brake system 200 to a great variety of different vehicles.

[0045] Referring now to figures 5 to 13, as shown in figure 5, the brake system 200 comprises a plurality of callipers 202 (in particular 202a and 202b). The callipers 202 are fluidly connected to a spring cannister 204.

[0046] The callipers 202 comprise lands 206 permitting attaching the spring cannister 204 to any of the callipers 202. In the particular arrangement of the brake system 200 of the present embodiment of the invention, there is one spring cannister 204 attached to the calliper 202a. A fluid path 208 (see figure 5) is defined extending from the spring cannister 204 to the other calliper 202b.

[0047] The fluid path 208 (see figure 5) is defined via piping 210 (see figure 9) with their ends being connected to openings for receiving nozzles 212 fluidly connected to cylinders 214. The cylinders 214 include pistons 211 in a slideably manner permitting the pistons 211 to slide within cylinders 214 during operation of the brake system 200. The nozzles 212 comprise fixtures 216 for receiving ends of the pipes 210 completing the fluid connection for delivery of the hydraulic fluid to the heads 209 (see figure 13) of the pistons 21 1 to drive the pistons 211 in order for their distal end abut and move the brake pads 218 of the callipers 202.

[0048] The hydraulic fluid is delivered to each calliper 202 to start operation of the brake system 200 by driving brake pads 218 (see figure 8) for contacting the respective rotor (as discussed above in relation to the conventional brake systems 10 shown in figure 1 ) to reduce the speed of the vehicle comprising the brake system 200. Delivery of the hydraulic fluid to pistons 211 actuating the pads 218 is done via the nozzles 212.

[0049] As shown in figure 9, the inner shell 207a of each calliper 202 comprises a body 222 having an outer surface 224 into which the nozzles 212 extend to define the hydraulic fluid path ending in the cylinders 214 permitting actuating the pistons 211 (located in the cylinders 214) when the hydraulic fluid is delivered into the cylinder 214 through the nozzles 212 for applying a pushing force to the brake pads 218.

[0050] Referring to figure 10, the cylinders 214 are defined via indentations 228 (containing the pistons 211 ) extending from an inner surface 226 of the inner shell 207a into the body 222 of the inner shell 207a. Each cylinder 214 comprise a side wall 230 surrounding the piston 211 , and an end area 232 for receiving the head 209 of the piston 21 1.

[0051] In accordance with the present embodiment of the invention, the end area 232 comprises the undercut 232 defining an extended chamber 238 (see figure 12).

[0052] The extended chamber 238 of the undercut 232 comprises one or more recesses 240 extending into the side wall 230 of the indentation 228 receiving the piston 21 1 . The recesses 240 indent into the side wall 230 at the location of the end area 232 of cylinder 214 where the piston 211 is parked when the brake system 200 is not operating.

[0053] In one arrangement there may be a single recess 240 that indents a particular distance into and around the periphery of the side wall 230 of the cylinder 214.

[0054] In an alternative arrangement, one or more recesses 230 may be defined at particular locations of the periphery side wall 230. For example, the particular arrangement shown in figures 11 and 12, comprises a plurality of recess 240a and 240b indenting into the side wall 230. As shown in figure 12, the outlets of the nozzles 212 are directly fluidly connected to the recesses 240.

[0055] At least one of the recesses 240 comprises a bleeding outlet fluidly connected to the bleed nipple 213 of a nozzle 212 attached to the outer surface 224 of the inner shell 207a.

[0056] The presence of the undercut 232 having at least one particular recess fluidly connected to a bleeding outlet is particularly useful because it ensures that brake bleeding occurs at the top of the extended chamber 238. This is because the particular recess 240 is configured to reach up to the highest point of the hydraulic circuit defining a spacing 241 at the highest point of the hydraulic circuit permitting fluidly connecting the bleeding nipple 213 with the spacing.

[0057] Due to the spacing 241 of the particular recess 240 of the undercut 230 being located at the highest point of the hydraulic circuit all air will be moving towards the spacing of the particular recess 240 ensuring that all of the air will be properly purged out of the hydraulic circuit. This is because all of the air (that will be present in the hydraulic circuit of the braking fluid at its highest point) is allowed to escape through the highest point in the hydraulic circuit.

[0058] In a particular arrangement, machine profiling of the undercut 232 may define particular shapes of extended chambers 238 having a recess 240 at the highest point of the hydraulic circuit so as to ensure that the bleeding nipple 213 of each calliper 202 is located at the highest point of the hydraulic circuit.

[0059] The presence of an undercut 232 is particularly useful because, depending on the particular shape of the undercut 232, it allows for installation of the brake system 200 in a multitude of orientations around the longitudinal axis of the brake system 200 or any other brake system operating under the same hydraulic principles.

[0060] For example, the location of the bleeding nipple 213 of the calliper 202 may be decided after installation of the brake system by machining the bleeding opening at the location that is at the highest point of the hydraulic circuit and where the spacing 241 defined by the recess 240 is located. In particular, the bleeding opening (onto which the bleeding nipple 213 will be fluidly connected) would be machined at a location so that the bleeding opening will be fluidly connected with the extended chamber 238, for example at the spacing 241 being remotely located from the piston, ideally at the highest point of the hydraulic circuit of the brake system 200.

[0061] Another advantage of the presence of the undercut 232, is that it allows to tailor the brake system 200 so that the brake system 200 may be fitted to a relatively large quantity of different type of vehicles. This is possible because the undercut 232 may be machined to a specific shape depending on the type of vehicle, the brake system 200 will be installed. For example, the undercut 232 may be configured in such a manner that the nozzles 212 (for receiving the hydraulic fluid or discharge of air trapped in the hydraulic circuit) may be located at locations which facilitate fitting the brake system 200 to different type of vehicles.

[0062] In particular, the nozzles 212 may be located offset with respect to the circumference of the inner end of the cylinder 214. In this manner, the nozzle 212 with the bleed nipple 213 may be installed at a location that improves the bleeding process as well as it permits, during installation, orienting the brake system 200 about the longitudinal axis of the brake system 200 in order to locate the nozzles 212 receiving the hydraulic fluid or the bleed nipple 213 and / or balance nipple 215 at locations to permit fitting of the brake system 200 to a great variety of vehicles.

[0063] In accordance with an embodiment of the invention there is provided a method for locating the bleeding nipple 213 at the highest point of the hydraulic circuit of a brake system 200 of a vehicle, the method comprises the step of installing a brake system 200 comprising the calliper 202, and orienting the brake system 200 such that the spacing 241 of the undercut 232 to be fluidly connected to a bleeding nipple 213 is located at the highest point of the hydraulic fluid. The method furhter comprises the step of fluidly connecting the bleeding nipple 213 to the spacing 241 .

[0064] In accordance with an embodiment of the invention there is provided a method for installing a brake system 200 comprising the caliper 202, the method comprising thestep of orienting the brake system 200 such that the spacing 241 of the undercut 232 can be accessed for machining the openings in the outer surface 226 of the inner shell 207a of the calliper 202 for receiving the hydraulic fluid and / or the bleeding nipple 213.

[0065] The methods further comprise the step of machining the recess prior installation of the brake calliper 202 for improving the bleeding process or fitting the brake system 200 to different types of vehicles.

[0066] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention. For example, the descriptions above relate to a particular embodiment of the invention in which the inventive concept, in particular the provision of undercuts 232 in cylinders 214, has been applied to the brake system 200 shown in figures 4 to 13. However, in alternative embodiments of the invention, this particular inventive concept may be applied to any hydraulic brake systems having cylinders in which pistons are displaced via the action of hydraulic fluid to actuate the pads of the brake system.

[0067] Further, it should be appreciated that the scope of the invention is not limited to the scope of the embodiments disclosed. These embodiments are intended for the purpose of exemplification only. Functionally equivalent products, formulations and methods are clearly within the scope of the invention as described herein.

[0068] Reference to positional descriptions, such as lower and upper, or inner and outer, are to be taken in context of the embodiments depicted in the figures, and are not to be taken as limiting the invention to the literal interpretation of the term but rather as would be understood by the skilled addressee.

[0069] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprise”, “comprises,” “comprising,” “including,” and “having,” or variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0070] Although terms such as first, second, third, etc. may be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0071] Spatially relative terms, such as “inner,” “outer,” “beneath”, “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature’s relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

[0072] Throughout this specification, unless the context requires otherwise, the word ''comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Claims

CLAIMS1 . A brake calliper comprising an inner shell and an outer shell coupled together to define a cavity for receiving a plurality of brake pads arranged in a spaced apart relationship with respect to each other defining at least one spacing for receiving a rotor, the inner shell comprising a body having an inner surface for abutment of one brake pad and an outer surface for receiving hydraulic fluid from a hydraulic circuit, the inner surface having at least one indentation for receiving a piston having a head for receiving the hydraulic fluid and a distal end to actuate the brake pad, and the outer surface defining a hydraulic path for delivery of the hydraulic fluid to the head of the piston, the indentation comprises a side wall for surrounding of the piston, and an end area for receiving the head of the piston, wherein the end area comprises an undercut extending into the side wall of the indentation for receiving the hydraulic fluid.

2. A caliper according to claim 1 wherein the undercut comprises one or more recesses extending into the side wall of the indentation.

3. A caliper according to claims 1 or 2 wherein the indentation defines a cylinder for receiving the piston.

4. A caliper according to any one of the preceding claims wherein the outer surface of the inner shell comprises at least one opening for receiving the hydraulic and / or bleeding the hydraulic circuit.

5. A caliper according to claim 4 wherein the opening is adapted for receiving a nozzle having either a fixture for receiving piping to deliver the hydraulic fluid into the indentation or a bleeding nipple or balance nipple.

6. A caliper according to claims 4 or 5 wherein the recess is adapted to be fluidly connected to the opening for delivering A caliper according to claims 4 or 5 wherein the recess is adapted to be fluidly connected to the opening for delivering brake fluid into the indentation or bleeding of the hydraulic circuit receiving the piston.

7. A caliper according to any one of claims 4 to 6 wherein the recess(es) is / are configured in order to offset the opening for receiving the hydraulic fluid or thebleed and / or balance nipple with respect to the circumference of the inner end of the indentation receiving the piston.

8. A caliper according to any one of the preceding claims wherein at least one of the recesses extend a particular distance into the side wall of the indentation, the particular distance being such that a spacing is defined at a particular location about the longitudinal axis of the indentation.

9. A caliper according to claim 8 wherein the spacing is located at the highest point of the hydraulic circuit for receiving any air contained in the hydraulic circuit.

10. A caliper according to claims 8 or 9 wherein the spacing is located at a location which permits fitting a brake system to different type of vehicles.11 . A caliper according to claim 10 wherein the undercut may be configured in such a manner that the bleed nipple and / or the balance nipple and / or opening for receiving the hydraulic circuit may be located at particular locations allowing fitting the brake system at particular orientations.

12. A caliper according to any one of the preceding claims wherein the inner shell comprises a body having an outer surface into which at least one opening extends to define the hydraulic fluid path ending in the indentation, and an inner surface for abutment of a brake pad permitting actuating the piston when the hydraulic fluid is delivered into the indentation through the inlet, wherein the opening is fluidly connected to at least one recess.

13. A caliper according to claim 10 wherein the one recess indents into and around the entire inner periphery of the side wall of the indentation.

14. A caliper according to claims 12 or 13 wherein there are one or more recesses indenting into particular locations of the periphery of the side wall.

15. A caliper according to any one of the preceding claims wherein there are at least three brake pads and two rotors, the two rotors being arranged in a spaced apart relationship with respect to each other defining a spacing for receiving one or more brake pads, and one spacing being defined between one rotor and the innersurface of the inner shell for receiving a brake pad, and another spacing being defined between one rotor and the inner surface of the outer shell for receiving a brake pad.

16. A caliper according to claim 15 wherein the inner and outer shell are coupled together defining a cavity for receiving two brake pads arranged in a spaced apart relationship with respect to each other defining a spacing for receiving a rotor.

17. A brake system comprising at least one brake calliper as defined in any one of claims 1 to 1618. A method for locating the bleeding nipple at the highest point of the hydraulic circuit of a brake system of a vehicle, the method comprises the step of installing a brake system comprising a calliper in accordance with the first aspect of the invention in the vehicle, orienting the braking system such that the spacing to be fluidly connected to the bleeding nipple is located at the highest point of the hydraulic fluid.

19. A method according to claim 18 furhter comprises the step of fluidly connecting the bleeding nipple to the spacing located at the highest point of the hydraulic circuit.

20. A method for installing a brake system comprising a calliper in accordance with the first aspect of the invention in a vehicle, the method comprising the step of orienting the brake system such that the spacing of the undercut can be accessed for machining the openings in the outer surface of the inner shell of the calliper for receiving the hydraulic fluid and / or the bleeding nipple.

21. A method according to claims 18 to 20 further comprising the step of machining the recess prior installation of the brake calliper for improving the bleeding process or fitting the brake system to different types of vehicles.

Images