FR2480380A1 - DISC BRAKE HAVING A PARTIAL TRIM COMPRISING A PRESSURE PLATE BETWEEN THE BRAKE JAW AND THE CLAMPING MEMBER OF THE JAW - Google Patents

Abstract

THE INVENTION RELATES TO A DISC BRAKE WITH A PARTIALLY LINING INCLUDING A PRESSURE PLATE BETWEEN THE BRAKE SHOE AND THE CLAMPING ELEMENT OF THE JAW. IN THIS DISC BRAKE IS PROVIDED AN OBLONGED PRESSURE PLATE 11 HAVING A CIRCULAR SPHERICAL CONTACT SURFACE 16 WITH A CORRESPONDING SURFACE 15 OF THE BRAKE SHOE CLAMP 14. A RETAINING SPRING 46 PROVIDES THE SUPPORT OF THE BRAKE SHOE 12 AGAINST THE FIXING STUDS 24 OF THE PRESSURE PLATE WHICH IS HELD AGAINST THE CLAMPING ELEMENT 14 BY A CALIPER-SHAPED SPRING 28 AND A STUD 31. THE INVENTION APPLIES TO DISC BRAKES A MECHANICAL OR HYDRAULIC CONTROL.

Description

The invention relates to a disc brake with partial lining

  with a central jaw clamp preferably circular.

  and with a rectangular or circular segmented brake shoe, and a pressure plate arranged symmetrically

  between the clamping element and the brake shoe.

  It is already known from the German patent application

  DE-AS 10 47 643, arranging a pressure plate between a lever-shaped brake shoe clamping member and a brake shoe of a partially-lined disc brake, to transform the oscillating movement of the lever. in a purely

linear brake jaw.

  It is an object of the present invention to provide a partial lining disc brake of the kind just mentioned by means of which a force centrally introduced by the brake jaw clamping member can be evenly distributed in the direction circumferential on the support plate or back

oblong of the brake shoe.

  To solve this problem, the invention provides that on the side facing the brake shoe, the contour of the pressure plate is adapted to the contour of the support plate and that, on the face facing the clamping member of jaw, it is adapted to the shape of the contour of the front surface of the jaw clamping element. In particular, the face of the pressure plate facing the brake jaw clamping element must have a circular contact surface whose diameter and width are adapted to the corresponding dimensions of the front surface of the clamping element. jaw. The contact surface is designed to conform to the profile of an axially protruding circular flange, which may be discontinuous by the provision of a slot on the outer face, in order to move the point of application inwardly.

  the force exerted on the pressure plate.

  On the face of the pressure plate opposite the contact surface shall be provided, symmetrically with respect to the radius of the middle disk, two support plate contact surfaces engaging the same support plate. In particular, it is intended to have studs in the middle of the contact surfaces of the support plate, these studs having to engage in corresponding holes in the support plate.

support plate.

  Although the invention provides only a central clamping element of the jaws, that is to say that it is provided, for example, a single brake piston actuated in mechanical or hydraulic mode, one can use a jaw brake of the type generally used for brakes provided with two hydraulic pistons arranged side by side in the circumferential direction. Indeed, the pressure plate according to the invention allows a regular distribution of the braking force, applied centrally over the entire surface of the oblong brake jaw or the support plate of the same

jaw.

  In addition. the invention takes account of the fact that the maximum possible diameter of a circular brake jaw clamping element can not ensure by itself a regular distribution of the pressure on the brake shoe, because it is clearly

  longer in the circumferential direction than in the radial direction.

  Instead of being cascular, the contact surface and

  the bearing surfaces of the support plate can also

  have an oval shape. The form provided by the invention is a conformation

  matlon front to prevent the bending of the plate

brake jaw support. -

  Slots, interrupting the continuity of the contact surface or bearing surfaces of support plates or collars

  circular, are intended to move inward the point of application

cation of the force.

  The mounting of the jaw support plate on the pressure plate is done in part by means of studs already mentioned. In addition, provision is made for this purpose a spring clip which will be described later. In order that the pressure plate can be adjusted with respect to the brake jaw clamp member in two mutually perpendicular and perpendicular planes, a particular embodiment provides that the contact surface of the pressure plate and the corresponding front contact surface of the brake jaw clamping member are spherical. The midpoint of the spherical surface shall be on the axis of the brake jaw clamp and on the face of the jaw opposite to the jaw clamp. Preferably, the midpoint of the spherical surfaces will be approximately at the level of the other

  jaw, that is to say at the level of the opposite brake jaw.

  Because there is a possibility of spherical twisting, that is to say a movement of the ball between the pressure plate and the jaw clamping member, partial overload is avoided.

  of the brake shoe if the brake is heavily loaded.

  The spherical conformation of the contact surface between the pressure plate and the clamping element of the brake jaws means that the shape of these two parts is in some way marrying with corresponding degrees of freedom. The spherical conformation of the thrust bearing thus achieves the best possible transmission of

  braking forces for all braking conditions.

  The pressure plate and the brake shoe clamping member must be tightened together by a retaining spring in order to obtain continuous application at the spherical thrust bearing. For this purpose, the retaining spring may be provided with two straight ends resting in radial holes in the jaw clamping member, and a stirrup-shaped part, which penetrates into a central cutout of the pressure plate, the stirrup-shaped part snapping into a stud mounted in the pressure plate, this stud being preferably directed in the radial direction. At the end with which it penetrates, the stud must be tapered, so that at the moment this stud enters the stirrup it results in a tension of the stirrup-shaped holding spring. According to another embodiment of the invention, the holding spring may be a spring clip which elastically clamps both the pressure plate and the jaw clamping element. This spring clip may consist in particular of a spring-loaded flat plate disposed flat between the pressure plate and the jaw clamp member and which at its radially outer and inner ends is provided with spring tabs. projecting axially respectively towards the pressure plate and towards the jaw clamp member and offset in the circumferential direction, these tongues being applied to the radially outer edges of the pressure plate or the element, respectively tightening

  jaw, springing radially outward or inward.

  The construction shall be designed so that, starting from the edge of the flat spring plate, centrally and radially outwards and inwards, relatively long spring tongues bent around the the clamping member of this brake shoe extends beyond the outer edges of this clamping member, to support it by tightening and that, near these tabs in the circumferential direction radially outwardly and inside, relatively short spring tongues extend over the outer edges of the pressure plate on which

they apply to block it.

  In order to secure the attachment of the brake shoe to the pressure plate, it is provided between the support plate and the pressure plate, according to an embodiment according to the invention, to mount a holding spring having a portion flat median provided with two medial spring legs located opposite each other, and allowing to grip the outer edge of the pressure plate, while on the opposite side, are provided two smaller spring branches bearing radially on the outer edge of the brake shoe, to press the brake shoe radially inward against a carrier of one. pressure plate. In this structure, the support preferably consists of at least two fastening studs pressure-fitted into holes in the pressure plate and penetrating holes in the brake jaw support plate, which is why the middle part of

  holding spring is provided with corresponding holes.

  As a result of the holding spring according to the invention and the fastening stud which holds it, it is possible without great effort, a possibility of adjustment in both planes. In addition, the conformation according to the invention of the spring and the pressure plate is intended to prevent slackening between the jaw clamping member and the pressure plate. The holding spring is also intended to connect the pressure plate and the jaw clamping element together and to prevent these two parts from clicking against one another. The purpose of the aforementioned holding spring arrangement is to prevent, on the one hand, the freedom of movement of the pressure plate and, on the other hand, that of the brake jaw support plate. In addition, at the time of loosening of the actuating element, by means of the covering of the spring tongues, the holding spring must release the brake linings of the disk. In the case of a fist-mounted caliper disc brake, since the spring tabs extend over the support plate, there is a bearing force between the padded support plate and the support of this support plate Thus, there is only one spring tongue resting on the support plate, so that the replacement of the brake lining can be carried out even when the brake caliper is raised. A notable advantage presented by the support of the plate

  pressure consists in the fact that friction forces

  of the pressure plate, for example in the bridge part of the stirrup, do not call into question the

  complete release of the lining when the brake is not applied.

  The invention will be better understood and other features

  will appear with the following description and accompanying drawings

  or: FIG. 1 is a radially axial section of a disk brake with partial lining according to the invention, showing a first version of a holding spring; FIG. 2 is a section along the line II; Figure 3 shows a section along the line III-III of Figure 2; Figure 4 is an enlarged rear view of the pressure plate 0.on the invention; Fig. 5 shows a radial view of the pressure plate according to the invention; FIG. 6 shows a front view of another version for a holding restor to be arranged between a clamping element e.eh = oire and a pressure plate; FIG. 7 is a radial view of the spring; Figure 8 is a view of the holding spring in the circumferential direction; FIG. 9 shows a perspective view of a spring tongue 34 of the holding spring according to FIGS. 6 to 8; FIG. 10 is a plan view of a holding spring intended to be arranged between the support plate and the pressure plate; and FIG. 11] is a side view of the holding spring according to the

figure 10.

  FIGS. 1 to 3 show a disc brake provided with a stirrup 36 surrounding a not shown brake disc, a direct brake brake jaw 27 and an indirectly controlled brake jaw 12 consisting of a support plate or plate

  back 1- and trim this brake 37.

  Between the support plate 13 and the pressure plate 11 ex-erant 1a pushes on celile-cieso disposed a spring 46 whose

  description is in the rest of this text.

  The pressure plate It bears, via a surface

  spherical ring 16, on the corresponding spherical frontal surface.

  15 of a jaw clamping member 14 which has been given the shape of a hollow piston axially slidable in a bore 38 of one of the airfoils L L = Hollow year 14 is actuated by a rattra-age pin 40 which can receive an axial force of a pin action.ne.ent 41. fctte axial force is produced

  by an actuating nut 43 rotating at the hub of an action lever

  42, connected with the actuating pin 4} by a recirculating ball thread L4. If we do. pivoting about the axis 26 B the actuating lever 42, the hollow piston] 4 is then moved towards the brake disc which is not shown on the fgure. In Figures 1 to 5, the pressure plate I1 has an oblong shape in the circumferential direction. On the face facing the hollow piston 4, the pressure plate has a bearing surface 16 provided on a flange 17 and whose spherical shape can only be seen in FIG. 1. The flange 17 and the surface of FIG. support 16 are i-narrowed in the radially exreure part 18, in order to move

  inwardly the point of application of the force of the hollow piston 14.

  On the opposite side, the pressure plate 1I provides on both sides, symmetrically with respect to the median radial plane 19, other collars 22, 23, with bearing surfaces 20, 21 engaging with the support plate 13. On bearing surfaces 20, 21 also,

  in the radially outer zone, the same

  ruptions 18 than that appearing on the support surface 16.

  In the middle of the flanges 22, 23 are provided studs 24, 25 which are engaged in the corresponding holes 50 of the support plate 13 (Figure 1) to form a support 49 on the plate

pressure 11.

  In the middle of the pressure plate 11, on the side facing the hollow piston 14, there is provided a recess 30 in which the stirrup portion 28 "engages with a stirrup-shaped holding spring 28, whose radial straight ends 28 'are accommodated in holes 29 of the hollow piston 14 extending in the circumferential direction, and in Figures 1 and 2 a pin 31 enters a corresponding hole in the pressure plate 11. The stud 31 passes through the recess 30 as well as the stirrup portion 28 of the spring 28. Since the point 45 of the stud is tapered, at the time of tightening, the stud 31 can tension the stirrup-shaped spring, so that the surfaces spherical 15, 16 are elastically tightened

one against the other.

  In FIGS. 1, 10 and 11, a holding spring 46 placed between the pressure plate 11 and the support plate 13 has

  essentially in the form of a flat plate 33 forming a spring, which -

  is disposed between the pressure plate 11 and the spring plate 13.

  On the radially outer and inner ends, this spring plate is provided at its center with spring tongues 47 directed towards the hollow piston 14, these tabs being applied from the outside in the manner of a spring to the pressure plate. He squeezes it. In the circumferential direction and on both sides, next to the middle tongue 47, extend on the radially outer edge of the support plate 13 spring tongues 48 which apply

  on the outer edge to lock it against the support 49.

  In FIGS. 1, 10 and 11, the holding spring 46 is relatively wide radially outwardly and, from its medial flat portion to its radially inner end, this spring is sufficiently narrow for the two studs 24, 25 pressed into the holes of the pressure plate 11 and which enter the holes 50 of the support plate 13 of the brake shoe 12,

  are located laterally beside the retaining spring 46.

  The mounting of the jaw clamp element 14, with the pressure plate It fixed to this element by means of the

  fixing 28, 31, is carried out so as to introduce this axial element-

  in the bore 38 of the stirrup, which allows the axial width

  of this stirrup. Another possibility is to get in

  riori the pin 31 of Figure I through a radial hole 52 of

  the stirrup and in the pressure plate 11.

  As shown in the indented part of FIG. 5, the height of the collars 22, 23 is a little larger than the sheet thickness of the holding spring 46, so that the holding spring 46 which, according to FIG. invention, must fit between the flanges at a sufficient clearance even when the brake shoes are applied

on the brake disc.

  Another possibility, presented alternatively for the holding spring 28, is shown in FIGS. 6 to 9. The holding spring 32 shown in detail in these figures is provided radially, inwardly and outwardly, with tongues of relatively short spring 35 which must extend over the plate of

  He presses it to tighten it. Virs in the circumferential direction

  Also, between the relatively short axial tongues 35 are radially inward and outwardly radially inwardly extending projections or spring projections 34 which are intended to axially cover the jaw clamping member 14. Tabs of FIG. spring 34 'slightly bent inwards serve to achieve better frictional engagement with the jaw clamping member 14. The middle planar portion 33 of the holding spring 32 is located between the pressure plate 11 and the jaw clamp 14, the surfaces pressed against each other of the pressure plate 11 and the jaw clamping member 14 to be flat when using the spring of

holding according to Figures 6 to 9.

  The fitting of the partial-lined disc brake according to the invention can be carried out as follows. Firstly, the radial holes 29 of the hollow piston 14 are aligned with the stirrup-shaped spring 28 by bringing the Uroite ends 28 'closer together. By releasing the caliper spring, the straight ends 28 'penetrate the radial holes 29. From the inside, the pressure plate 11 is then inserted on the spring 28, until the spherical surfaces 15, 16 touch. The recess 30 has a shape sufficiently flat so that the stirrup spring then takes the position shown

in Figure 3.

  The pin 31 is then inserted into the pressure plate, which has the effect of elastically blocking the pressure plate 11 with the hollow piston 14.However, there can still be a rotary movement of the pressure plate 11 in two planes. along

spherical surfaces 15, 16.

  Then, the spring clip 46 is attached to the front face of the pressure plate 11 facing the disc and the brake shoe 12 can then be mounted on the studs 24, 25 of the pressure plate 11, the spring tabs. 48 being resiliently biased to the outer radial ply of the support plate 13. The spring-forming spring plate is narrow enough that the two studs 24, 25 and the flanges 22, 23 can extend laterally.

passing by the spring.

  Of course, the embodiments described are not

  in no way limitative of the invention.

Claims (18)

  1. Partially-lined disc brake with a preferably circular central jaw clamp and a rectangular or circular segmented brake shoe and a pressure plate symmetrically disposed between the clamping element brake shoe and brake shoe, characterized in that, on the side facing the brake shoe (12), the contour of the pressure plate (11) is adapted to the contour of the support plate (13) and, on the side facing the jaw clamping member (14), it is adapted to the shape of the contour of the surface   front (] 5) of the brake jaw clamping member (14).   2. Disc brake with partial lining according to claim   cation 1, characterized in that the face of the pressure plate (11) facing the jaw clamping member (14) is provided with a circular contact surface (16), the diameter and width of which are adapted to the corresponding dimensions of the front surface (15)   the brake jaw member (14).   3. Disc brake with partial lining according to the   cation 2, characterized in that the contact surface (16) is formed   on a projecting circular collar (17).   4. Partially lined disc brake according to one of   claims 2 or 3, characterized in that the contact surface (16)   or flange (17) are provided with an interruption slot (18) on the outer face.   5. Disc brake with partial lining according to the claim   4, characterized in that the interrupting slot (18) extends symmetrically in the direction of the disc radius (19) passing through the midpoint of the contact surface (16) at an angle of eighty   at a hundred degrees and preferably about ninety degrees.   6. Partially lined disc brake according to any one of   Claims 2 to 5, characterized in that on the face of the   pressure plate opposite the contact surface (16), are provided symmetrically with respect to the median disc radius (19) two surfaces   support plate contact (20, 21).   7. Disc brake with partial lining according to claim   cation 6, characterized in that the support contact surfaces (20, 21) are formed on protruding circular flanges axial (22, 23).   8. Partially lined disc brake according to one of   claim 6 or 7, characterized in that the surfaces of   contact (20, 21) of the support plates or the flanges (22, 23) are provided with a stop gap (18) on the radially outer face. 9. Partially lined disc brake according to any one of   Claims 6 to 8, characterized in that in the medium of   contact surfaces of the support plates (20, 21) are provided with studs (24, 25) which engage with corresponding holes in the   support plate (13) of the brake shoe (12).   10. Partially lined disc brake according to any one of   Claims 1 to 9, characterized in that the surface of   contact (16) of the pressure plate (11) and the corresponding front contact surface (15) of the jaw clamp (14) are spherical in shape.   He. Disc brake with partial lining according to claim   cation 10, characterized in that the midpoint of the spherical surfaces (15, 16) is located on the axis (26) of the clamping element brake shoe (14).   12. Disc brake with partial lining according to claim   cation 11, characterized in that the midpoint of the spherical surfaces (15, 16) is located on the brake jaw face (12)   opposed to the brake jaw clamping member (14).   13. Partially lined disc brake according to claim   12, characterized in that the midpoint of the spherical surfaces (15, 16) is situated approximately at the level of the other opposite brake shoe (27).   14. Partially lined disc brake according to any one of   Claims 1 to 13, characterized in that the plate   pressure (11) and the jaw clamp (14) are tightened one   against the other by a holding spring (28, 32).   15. Partially lined disc brake according to claim   cation 14, characterized in that the holding spring (28) is provided with two straight ends (28 ') resting in radial holes (29) of the jaw clamping member (14) and a shaped portion stirrup bar (28 ") penetrating into a central cutout (30) of the pressure plate (11), the stirrup-shaped part engaging in a stud (31) mounted in the pressure plate (11), this stud being   preferably directed in the radial direction. 1 2   16. Partially lined disc brake according to claim   cation 14, characterized in that the holding spring is a spring clip (32) which clamps the plate   pressure (11) than the jaw clamping member (14).   Partial-lined disc brake according to claim 16, characterized in that the spring clip (32) consists of a flat spring plate (33) lying flat between the pressure plate (11). and the jaw clamp member (14), which at its radially outer and inner ends is provided with spring tongues (35,34) projecting axially respectively toward the pressure plate (11) and to the jaw clamping member (14) and offset in the circumferential direction, these spring tongues radially outwardly and inwardly on the radially outer edges, respectively   the pressure plate (11) or the jaw clamping member (14).   18. Disc brake with partial lining according to claim   cation 17, characterized in that spring tongues (34), bent radially outwardly and inwardly, extend from the rim of the spring plate (33) centrally towards the clamping member of jaw (14) and that, near these tongues in the circumferential direction, tabs (35) also extend radially outwardly and inwardly over the outer plates of the pressure plate (11). ) on which they apply to block it.   19. Partially lined disc brake according to any one of   claims I to 18, characterized in that between the plate   support (13) and the pressure plate (11), there is provided a holding spring (46) with a flat median part, this spring being provided with two medial and opposite limbs (47), by means of which it encloses the outer edge of the pressure plate (11), while on the opposite side, two smaller spring legs (48) are provided to apply to the radially outer flange of the brake shoe (12), these branches spring biasing the brake shoe (12) radially inwardly against a support (49) of a pressure plate (11).   20. Partially lined disc brake according to claim   cation 19, characterized in that the support (49) consists of 2480380   minus two studs (24, 25) which are pressed into the holes of the pressure plate (11) and penetrate into holes (50) in the support plate (13) of the brake shoe (12), the flat medial portion of the holding spring (46) being sufficiently narrow for this.