GB2119879A - Disc brakes - Google Patents

Abstract

A disc (1) for a vehicle disc brake comprises two arcuate components (5, 6) which are coupled together at adjacent ends by fasteners passed through superimposed openings in overlapping step-like abutments (18, 19). Each fastener comprises a tubular device (21), suitably a dowel or roll pin, which fits tightly in a radial bore (2) defined by the openings, in combination with a bolt (28) for clamping the abutments (18, 19) into mating engagement. <IMAGE>

Description

SPECIFICATION Disc brakes This invention relates to discs for vehicle disc brakes, particularly but by no means exclusively, of the kind for use with railway vehicles.

According to our invention in a disc for a vehicle disc brake comprising at least two components of arcuate outline, portions at adjacent ends of adjacent components are staggered to form overlapping abutments, and fastening means are inserted through superimposed openings in complementary pairs of abutments to couple the components together.

Constructing the disc from more than one compo nentfacilitates manufacture and the mounting of the disc on an associated wheel hub, axle and the like, and the arrangement of the abutments and of the fastening means provide joints which couple the components together rigidly to act as a single unit in use.

The fastening means preferably comprises a bolt or similar tensile fastener inserted into a radial bore defined by the openings and which contains a tightly fitting tubular device passing through the joint region. The tubular device may be a dowel pin or a spring roll pin.

Two embodiments of our invention will now be described by way of example with reference to the accompanying drawings, in which: Figure lisa plan of the part of a disc for a disc brake of a rail vehicle; Figure2 is a section on line 2-2 of Figure 1; and Figure 3 is a similar view to Figure 2 but showing a modification.

The disc 1 illustrated in Figures 1 and 2 of the drawings is of annular outline having a central opening 2 to receive a hub (not shown) and has a pair of opposed external braking faces 3, 4 with which friction brake pads (also not shown) are engageable when the disc is incorporated in a disc brake for a rail vehicle.

The disc comprises two arcuate components 5, 6, each conveniently in the form of one-piece casting and each comprising a pair of plates 7, 8; 9, 10 held in a spaced relationship by radial cooling fins 11, 12 with the outer faces, constituting the braking faces 3, 4, lying in spaced parallel planes.

The inner peripheral edge of the disc is provided with angularly spaced inwardly extending radial projections 13 having part-cylindrical axial recesses 14 at their inner ends. When the disc is mounted on a hub these recesses register with corresponding recesses of the hub to receive spring roll-pins under compression, a clearance being present between the projections 13 and the hub. The roll-pins serve to centre the disc on the hub and provide a compliant mounting which is able to accommodate thermal changes in the dimensions of the disc brake.

The plates 7, 8; 9, 10 of each disc component 5, 6 are bridged at their ends by substantial integral bodies 15, 16 of metal, and the joint or split-line 17 between mating portions at adjacent ends is stag gered in a step-like manner to form two overlapping abutments 18, 19.

A radial bore 20 defined by superimposed openings in the bodies 15, 16 passes through both abutments and receives a tightly fitting tubular dowel pin 21. The dowel pin 21 is divided transversely near its radially innermost end to form two slightly spaced dowel pieces 22, 23, and each piece has an enlarged head 24, 25 seated in respective counterbored recesses 26, 27 in the abutment 15 and 16. The two dowel pin pieces 22 and 23 are clamped together by a bolt 28. The two disc components 5 and 6 are thus rigidly coupled together. The stepped form of the abutment 18, 19, together with the tight fit of the dowel pin 21, provides positive location of the disc components relative to each other.

Although only one joint is shown in the drawings the other joint for the opposite end of the components 5,6 is identical so that both components of the disc brake are of identical form.

The two components can easily be uncoupled for replacement etc. by removing the bolt 28 and dowel pin 21, and drawing the components apart in opposite radial directions.

In Figure 3 the dowel pin 21 is replaced by a spring roll pin 30, driven into the bore 20, and clamp washers 31,32 having spigots 33,34 inserted into the ends of the roll pin 30.

The construction of Figure 3 is otherwise the same as that of Figures 1 and 2 and corresponding reference numerals have been applied to corresponding parts.

1. A disc for a vehicle disc brake comprising at least two components of arcuate outline, in which portions at adjacent ends of adjacent components are staggered to form overlapping abutments, and fastening means are inserted through superimposed openings in complementary pairs of abutments to couple the components together.

2. A disc as claimed in claim 1, in which the abutments are of complementary stepped outline.

3. A disc as claimed in claim 1 or claim 2, in which a radial bore defined by the openings receives the fastening means, and the fastening means comprises a tightly fitting tubular device which is received in the bore, in combination with a bolt for clamping the abutment faces of each pair into mating engagement.

4. A disc as claimed in claim 3, in which the tubular device comprises a two-piece dowel of which the pieces are inserted into opposite ends of the bore, and each piece has an enlarged head which is clamped, by the bolt, against seatings in counterbored recesses in the two abutments.

5. A disc as claimed in claim 3, in which the tubular device comprises a roll pin, and the bolt acts on the components through a pair of clamp washers which are clamped against seatings in counterbored recesses in the two abutments and include spigots which are received in opposite ends of the roll pin.

6. A disc for a vehicle disc brake substantially as described herein with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Disc brakes This invention relates to discs for vehicle disc brakes, particularly but by no means exclusively, of the kind for use with railway vehicles. According to our invention in a disc for a vehicle disc brake comprising at least two components of arcuate outline, portions at adjacent ends of adjacent components are staggered to form overlapping abutments, and fastening means are inserted through superimposed openings in complementary pairs of abutments to couple the components together. Constructing the disc from more than one compo nentfacilitates manufacture and the mounting of the disc on an associated wheel hub, axle and the like, and the arrangement of the abutments and of the fastening means provide joints which couple the components together rigidly to act as a single unit in use. The fastening means preferably comprises a bolt or similar tensile fastener inserted into a radial bore defined by the openings and which contains a tightly fitting tubular device passing through the joint region. The tubular device may be a dowel pin or a spring roll pin. Two embodiments of our invention will now be described by way of example with reference to the accompanying drawings, in which: Figure lisa plan of the part of a disc for a disc brake of a rail vehicle; Figure2 is a section on line 2-2 of Figure 1; and Figure 3 is a similar view to Figure 2 but showing a modification. The disc 1 illustrated in Figures 1 and 2 of the drawings is of annular outline having a central opening 2 to receive a hub (not shown) and has a pair of opposed external braking faces 3, 4 with which friction brake pads (also not shown) are engageable when the disc is incorporated in a disc brake for a rail vehicle. The disc comprises two arcuate components 5, 6, each conveniently in the form of one-piece casting and each comprising a pair of plates 7, 8; 9, 10 held in a spaced relationship by radial cooling fins 11, 12 with the outer faces, constituting the braking faces 3, 4, lying in spaced parallel planes. The inner peripheral edge of the disc is provided with angularly spaced inwardly extending radial projections 13 having part-cylindrical axial recesses 14 at their inner ends. When the disc is mounted on a hub these recesses register with corresponding recesses of the hub to receive spring roll-pins under compression, a clearance being present between the projections 13 and the hub. The roll-pins serve to centre the disc on the hub and provide a compliant mounting which is able to accommodate thermal changes in the dimensions of the disc brake. The plates 7, 8; 9, 10 of each disc component 5, 6 are bridged at their ends by substantial integral bodies 15, 16 of metal, and the joint or split-line 17 between mating portions at adjacent ends is stag gered in a step-like manner to form two overlapping abutments 18, 19. A radial bore 20 defined by superimposed openings in the bodies 15, 16 passes through both abutments and receives a tightly fitting tubular dowel pin 21. The dowel pin 21 is divided transversely near its radially innermost end to form two slightly spaced dowel pieces 22, 23, and each piece has an enlarged head 24, 25 seated in respective counterbored recesses 26, 27 in the abutment 15 and 16. The two dowel pin pieces 22 and 23 are clamped together by a bolt 28. The two disc components 5 and 6 are thus rigidly coupled together. The stepped form of the abutment 18, 19, together with the tight fit of the dowel pin 21, provides positive location of the disc components relative to each other. Although only one joint is shown in the drawings the other joint for the opposite end of the components 5,6 is identical so that both components of the disc brake are of identical form. The two components can easily be uncoupled for replacement etc. by removing the bolt 28 and dowel pin 21, and drawing the components apart in opposite radial directions. In Figure 3 the dowel pin 21 is replaced by a spring roll pin 30, driven into the bore 20, and clamp washers 31,32 having spigots 33,34 inserted into the ends of the roll pin 30. The construction of Figure 3 is otherwise the same as that of Figures 1 and 2 and corresponding reference numerals have been applied to corresponding parts. CLAIMS

1. A disc for a vehicle disc brake comprising at least two components of arcuate outline, in which portions at adjacent ends of adjacent components are staggered to form overlapping abutments, and fastening means are inserted through superimposed openings in complementary pairs of abutments to couple the components together.

2. A disc as claimed in claim 1, in which the abutments are of complementary stepped outline.

3. A disc as claimed in claim 1 or claim 2, in which a radial bore defined by the openings receives the fastening means, and the fastening means comprises a tightly fitting tubular device which is received in the bore, in combination with a bolt for clamping the abutment faces of each pair into mating engagement.

4. A disc as claimed in claim 3, in which the tubular device comprises a two-piece dowel of which the pieces are inserted into opposite ends of the bore, and each piece has an enlarged head which is clamped, by the bolt, against seatings in counterbored recesses in the two abutments.

5. A disc as claimed in claim 3, in which the tubular device comprises a roll pin, and the bolt acts on the components through a pair of clamp washers which are clamped against seatings in counterbored recesses in the two abutments and include spigots which are received in opposite ends of the roll pin.

6. A disc for a vehicle disc brake substantially as described herein with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.

7. A disc for a vehicle disc brake substantially as described herein with reference to and as illustrated in Figure 3 of the accompanying drawings.