JP2015169301A - floating type disk brake - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floating type disk brake capable of suppressing occurrence of dragging of a pad, and attaining cost reduction and weight saving.SOLUTION: In a floating type disk brake, a cylinder 28, to which a first piston 18a and a second piston 19a moving to opposite sides of an axial direction in braking are fitted, is configured separately from a support 2b that is fixed to a vehicle body and supports outer and inner pads 3b, 4b in a movable manner in the axial direction; and the cylinder 28 is supported in a detachable manner to the support 2b.

Description

  The present invention relates to an improvement of a floating disc brake for braking a vehicle.

  As a disc brake for braking a vehicle such as an automobile, a floating disc brake in which a caliper is supported so as to be able to move in the axial direction with respect to a support has been conventionally used. Known from.

  FIG. 13 shows a floating disc brake of a first example of a conventional structure described in Patent Document 1. The floating disc brake 1 includes a support 2, outer and inner pads 3 and 4, and a caliper 5.

  Of these, the support 2 is the inner side of the rotor 6 that rotates with the wheels (the upper side in FIG. 13 and refers to the center in the width direction of the vehicle when assembled to the vehicle. On the contrary, the outer side is the width direction of the vehicle. It is fixed to the vehicle body (a suspension device such as a knuckle, not shown) in a state of being adjacent to the same. The outer and inner pads 3 and 4 are arranged on the outer side (lower side in FIG. 13) and the inner side of the rotor 6 so as to be movable in the axial direction with respect to the support 2. Has been. In the present specification and claims as a whole, “axial direction”, “radial direction” and “circumferential direction” refer to the axial direction, radial direction and circumferential direction of the rotor unless otherwise specified.

  Further, the caliper 5 has a caliper claw 7 at the outer side end portion, a cylinder portion 9 fitted with a piston 8 at the inner side end portion, and the caliper claw 7 at a position straddling the outer peripheral edge portion of the rotor 6. A bridge portion 10 that connects the cylinder portion 9 is provided. The caliper 5 has the inner side surface of the caliper claw 7 facing the outer side surface of the outer pad 3 and the tip end surface of the piston 8 facing the inner side surface of the inner pad 4. The support 2 is supported so as to be movable in the axial direction. For this purpose, in the example shown in the figure, a pair of slide pins 11 having their base ends supported and fixed to the caliper 5 are inserted into a pair of slide holes 12 provided in the support 2.

  In order to perform braking, pressure oil is fed into the cylinder portion 9, and the inner pad 4 (lining thereof) is pressed against the inner side surface of the rotor 6 from the top to the bottom of FIG. Then, as a reaction of this pressing force, the caliper 5 moves upward in FIG. 13 based on the sliding between the slide pins 11 and the slide holes 12, and the caliper pawl 7 is moved to the outer pad 3 Lining) is pressed against the outer side surface of the rotor 6. As a result, the rotor 6 is strongly clamped from both sides in the axial direction, and braking is performed.

However, in the case of the conventional floating disc brake 1 having the above-described structure, a so-called drag is generated in which the outer and inner pads 3 and 4 and the side surface of the rotor 6 rub against each other even after the brake is released. It becomes easy to let.
That is, when the brake is released, the piston 8 is pulled back (rolled back) into the cylinder portion 9 by the elasticity of the seal member 13 provided in the cylinder portion 9, so that the inner pad 4, the rotor 6, A clearance C is secured between the two. On the other hand, the clearance between the outer pad 3 and the rotor 6 is based on the contact between the outer pad 3 and the rotor 6, and the caliper 5 is connected to the support 2 by a part of the clearance C. On the other hand, it is secured by displacing to the outer side. That is, in the case of the first example of the conventional structure, the clearance C secured by the elastic force of the seal member 13 is set between the inner pad 4 and the rotor 6, the outer pad 3 and the rotor 6. It will be shared with the part between. Accordingly, it becomes difficult to secure a sufficient clearance between the inner pad 4 and the rotor 6 and a clearance between the outer pad 3 and the rotor 6, and drag is likely to occur.

  In view of such circumstances, for example, Patent Documents 2 and 3 describe floating disc brakes that can suppress the occurrence of dragging. FIG. 14 shows a floating disc brake 1a of a second example having a conventional structure described in Patent Document 2.

The floating disc brake 1a includes a support 2a, outer and inner pads 3a and 4a, and a yoke 14.
The support 2a includes a support body 15 provided on the outer side (lower side in FIG. 14) and a cylinder portion 16 provided on the inner side (upper side in FIG. 14), and the rotor 6 (see FIG. 13). ) Is fixed to the vehicle body in a state adjacent to. Of these, the support body 15 supports the outer and inner pads 3a and 4a so as to be movable in the axial direction. The cylinder portion 16 is provided with a pair of cylinder spaces 17. Both the cylinder spaces 17 are opened on both sides in the axial direction, and the first piston 18 and the second piston 19 are fitted in a liquid-tight manner so as to be movable in the axial direction. Further, a portion of the cylinder space 17 between the first piston 18 and the second piston 19 is a hydraulic chamber 20 for introducing pressure oil.

  The yoke 14 is supported by the support 2a through the slide pin 21 so as to be movable in the axial direction, the pressing portion 22 at the outer side end, the pressed portion 23 at the inner side end, A bridge portion 24 that connects the pressing portion 22 and the pressed portion 23 is provided in the intermediate portion in the axial direction. Of these, the inner side surface of the pressing portion 22 is opposed to the outer side surface of the outer pad 3, and the outer side surface of the pressed portion 23 is opposed to the distal end surface of the second piston 19.

  When braking is performed, pressure oil is fed into the hydraulic chamber 20 to push the first piston 18 and the second piston 19 away from each other in the axial direction (opposite direction). Then, the first piston 18 presses the inner pad 4a against the inner side surface of the rotor 6 from the top to the bottom in FIG. At the same time, the pressed portion 23 is pressed upward from the bottom of FIG. 14 by the second piston 19, and the yoke 14 is moved upward in FIG. 14 with respect to the support 2a. As a result, the outer pad 3a is pressed against the outer side surface of the rotor 6 from the bottom to the top in FIG. As a result, the rotor 6 is strongly clamped from both sides in the axial direction, and braking is performed.

  When the brake is released, the first piston 18 is moved into the cylinder space 17 by the elasticity of the first seal member 25 sandwiched between the outer peripheral surface of the first piston 18 and the inner peripheral surface of the cylinder portion 16. Pulled back. The second piston 19 is also pulled back into the cylinder space 17 by the elasticity of the second seal member 26 sandwiched between the outer peripheral surface of the second piston 19 and the inner peripheral surface of the cylinder portion 16. . Therefore, a part of the clearance secured by the elasticity of the first seal member 25 is not used for the clearance between the outer pad 3a and the rotor 6. Therefore, a sufficient clearance can be secured between the rotor 6 and the outer and inner pads 3a and 4a. Therefore, the floating disc brake 1a of the second example having such a conventional structure is advantageous in suppressing the occurrence of dragging.

However, in the case of the second example of the conventional structure as described above, the following new problem is caused by the fact that the cylinder portion 16 is integrally provided on the inner side portion of the support 2a. Will occur.
That is, since the cylinder portion 16 integrally formed with the support 2a is disposed on the inner side portion of the inner pad 4a, the floating disc brake 1a is attached to the vehicle body, In order to remove the inner pad 4a from the support 2a, it is necessary to be able to remove the inner pad 4a not in the axial direction but in the radial direction. Therefore, in the case of the second example of the conventional structure, a pair of locking projections 88a and 88b (89a and 89b) are provided at both circumferential ends of the outer and inner pads 3a and 4a. The locking projections 88a and 88b (89a and 89b) are engaged with the pair of engaging portions 90a and 90b constituting the support body 15 from the outside in the radial direction. Further, in order to suppress the rattling of the outer and inner pads 3a and 4a supported in this manner, the outer peripheral edge portions of the outer and inner pads 3a and 4a, the radially inner side surface of the bridge portion 24, Between these, a spring (not shown) is arranged. At the time of pad replacement, the yoke 14 is retracted from the radially outer side of the outer and inner pads 3a, 4a so that the outer and inner pads 3a, 4a are removed radially outward (or radially outward). Can be attached from the side). However, in the case of the second example of the conventional structure having such a configuration, the sliding resistance of the yoke 14 is increased by the reaction force of the spring, so that the effect of suppressing drag is reduced. .

  Further, since the cylinder portion 16 is provided integrally with the support 2a, the braking torque is not supported and the cylinder portion 16 which does not need such a high strength needs to be made of a material having a high strength. Cause an increase in cost and weight. Further, since it is necessary to secure an arrangement space for a tool for processing a seal groove or the like on the inner peripheral surface of the cylinder portion 16, an outer bridge portion 27 is provided on the outer side portion of the support 2a as in the structure shown in the drawing. When providing, the freedom degree regarding the shape and installation position of this outer bridge part 27 becomes low. When the work for assembling the first and second pistons 18 and 19 and the first and second seal members 25 and 26 in the cylinder space 17 is performed, the support 2a having a large volume is attached to a clean room. There is also a problem that a large clean room is necessary because it is necessary to carry in and work inside.

  Although illustration is omitted, both the outer and inner pads are supported so as to be movable in the axial direction with respect to the support by using a pair of pad pins as in the structure described in Patent Document 3, for example. Is also possible. However, when such a configuration is adopted, it is necessary to dispose both the pad pins further radially outward than the outer peripheral edge of the rotor, so that such pad pins are covered from the radially outer side. With respect to the bridge portion of the yoke provided in (3), it is difficult to ensure the thickness dimension in the radial direction, and it may be difficult to ensure the strength of the yoke.

Japanese Utility Model Publication No.57-1922 Japanese Patent Laid-Open No. 58-94642 JP 2013-204742 A JP 2012-97894 A

  In view of the above-described circumstances, the present invention has been invented to realize a structure that can suppress the occurrence of pad dragging and that is advantageous for cost reduction and weight reduction.

The floating type disc brake of the present invention includes a support, both outer and inner pads, a yoke, a cylinder, and both first and second pistons.
The support is fixed to the vehicle body in a state adjacent to the rotor that rotates together with the wheels.
The outer and inner pads are supported with respect to the support in a state that allows movement in the axial direction and restricts movement in the radial direction and the circumferential direction.
The bridge includes a pressing portion for pressing the outer side surface of the outer pad at the outer side end portion, a pressed portion at the inner side end portion, and a bridge that connects the pressing portion and the pressed portion at an intermediate portion in the axial direction. Each of which is supported so as to be movable in the axial direction with respect to the support.
The cylinder is disposed on the inner side of the inner pad and has a cylinder space that is open on both sides in the axial direction.
The first and second pistons are fitted in the cylinder space so as to be movable in the axial direction. Of these, the first piston presses the inner side surface of the inner pad during braking, and the second piston presses the outer side surface of the pressed portion during braking.

  In particular, in the floating type disc brake of the present invention, the cylinder configured separately from the support is supported so as to be removable (detachable) from the support.

When implementing the floating type disc brake of the present invention as described above, for example, as in the invention described in claim 2, the cylinder is used, for example, using a fastening member such as a bolt, a stud bolt, or a nut. It is fixedly fixed to the support so that it cannot be displaced.
Or like the invention described in Claim 3, the said cylinder is supported with respect to the said support so that some displacement is possible. For this purpose, for example, the cylinder is supported to the support via an elastically deformable bush, a ball joint, or the like.

When the floating disc brake according to the present invention is implemented, for example, as in the invention described in claim 4, the convex engagement protrusions provided at the circumferential side edges of the outer and inner pads, respectively. The piece can be moved in the axial direction by a concave torque receiving portion provided on the outer side portion and the inner side portion at both ends in the circumferential direction of the support with the openings facing each other in the circumferential direction. And it engages in the state which controlled the movement regarding the circumferential direction and radial direction.
When the invention described in claim 4 is carried out, as in the invention described in claim 5, for example, the outer side portion of the support is connected to the outer side torque receiving portion and the rotation side. An outer bridge portion for connecting the outlet side torque receiving portion in the circumferential direction is provided.

  Further, when the floating disc brake of the present invention is implemented, the support and the cylinder are made of different materials (for example, the cylinder is stronger than the support, as in the invention described in claim 6). Build from low material).

  When the floating type disc brake of the present invention is implemented, for example, as in the invention described in claim 7, the first piston and the second piston are mechanical types using an electric motor, an electromagnetic unit or the like. Or driven by a driving means other than hydraulic, such as pneumatic.

According to the floating disc brake of the present invention having the above-described configuration, it is possible to suppress the occurrence of pad dragging, and it is advantageous in reducing cost and weight.
That is, in the case of the present invention, as in the case of the second example of the conventional structure described above, the first and second pistons are fitted in the cylinder space. Both pistons can be pulled back into the cylinder space. Therefore, it is possible to secure a sufficient clearance between the outer and inner pads and the rotor. Therefore, according to the present invention, the occurrence of pad drag can be effectively suppressed.

In particular, in the case of the present invention, the cylinder is configured separately from the support, and the cylinder is removably supported with respect to the support. Therefore, the following effects can be obtained in addition to the above effects.
First, the pad replacement work can be performed with the cylinder removed from the support. Therefore, as the support structure of the pad with respect to the support, a structure that engages in the radial direction (in the case of the second example of the conventional structure) and a structure that uses the pad pin are not adopted, but one structure as in the first example of the conventional structure. It is possible to employ an axially engaging structure (structure described in claim 4) that is widely employed in floating type disc brakes having a piston. This makes it possible to install a spring (pad clip) that suppresses rattling of the pad without increasing the sliding resistance of the yoke, so that the occurrence of pad drag can be effectively suppressed. In addition, since the restriction of the thickness dimension in the radial direction of the bridge portion constituting the yoke can be reduced as compared with the case where the pad pin is used, the freedom of material selection for the yoke is improved (the strength of the light material is low but the strength is low). This is advantageous in reducing the weight of the yoke.

In addition, the support and pad of the present invention are between the support and pad used in a floating type disc brake (which does not matter the caliper material) having one piston as in the first example of the conventional structure. Common use becomes possible. This is advantageous in reducing costs.
In addition, because cylinders with different cylinder diameters can be attached to and exchanged with the support, support (and pads) can be shared between multiple floating disc brakes with different cylinder diameters, further reducing costs. Can be planned.
Furthermore, since only the operation of attaching the first and second pistons and the like to the cylinder (sub-assembly operation) needs to be performed in the clean room, it is possible to reduce the size of work target components to be performed in the clean room. Therefore, it is possible to save space in the clean room.

  Further, as in the invention described in claim 3, if the cylinder is supported so as to be able to be slightly displaced with respect to the support, the first and second pads can be provided even when the outer and inner pads are partially worn. Each piston can effectively prevent the inner peripheral surface of the cylinder from being damaged (twisted).

  Further, as in the case of the invention described in claim 5, even when the outer bridge portion is provided on the outer side portion of the support, the tool used for machining the inner peripheral surface of the cylinder and the outer bridge portion are interfered with each other. You do n’t have to. For this reason, the freedom degree regarding the shape and installation position of this outer bridge part can be improved.

  Further, when the support and the cylinder are made of different materials as in the invention described in claim 6, the cylinder and the support are made by making the cylinder of the material lower in strength than the support. Compared to the case of making from the same material, the cost and weight can be reduced.

  Further, when the first and second pistons are driven by a driving source other than hydraulic pressure as in the invention described in claim 7, the driving means that tends to be heavy is not a yoke that moves in the axial direction during braking, Since it can be installed around and / or inside the cylinder supported by the support, it is not necessary to increase the sliding resistance of the yoke, which leads to deterioration of pad dragging.

The perspective view which shows the floating type disc brake of the 1st example of embodiment of this invention in the state seen from the outer side and radial direction outer side. The perspective view which similarly shows the state seen from the inner side and radial direction outer side. The rear view which similarly shows the state seen from the inner side. The rear view which abbreviate | omits a yoke similarly. Similarly AA sectional drawing of FIG. Similarly BB sectional drawing of FIG. The disassembled perspective view which similarly shows the state seen from the outer side. The disassembled perspective view which similarly shows the state seen from the inner side. The schematic diagram equivalent to the AA cross section of FIG. 3 which shows the 2nd example of embodiment of this invention. The enlarged view of the part corresponded to the C section of Drawing 3 showing the floating type disc brake of the 3rd example in the state where the bolt for cylinder attachment was removed similarly. The figure which similarly corresponds to FIG. Sectional drawing which shows another 8 examples similarly employable as a support structure of a 3rd example. The fragmentary sectional view which shows the floating type disc brake of the 1st example of conventional structure in the state seen from the outer diameter side of the rotor. The fragmentary sectional view which shows the 2nd example of a conventional structure similarly.

[First example of embodiment]
A first example of the embodiment of the present invention will be described with reference to FIGS. The floating type disc brake 1b of this example is used for braking an automobile, and as in the case of the second example of the conventional structure, the support 2b, the outer and inner pads 3b and 4b, and the yoke 14a. And a cylinder 28 and first and second pistons 18a, 19a.

  The support 2b is made by casting an iron-based alloy such as cast iron, and is fixed to the vehicle body at the inner side portion of the rotor 6 that rotates together with the wheels, and is installed so as to straddle the rotor 6. . Such a support 2b includes a base 29, a pair of inner side arm portions 30a and 30b, a pair of outer side arm portions 31a and 31b, a pair of connecting portions 32a and 32b, and an outer bridge portion 27a. Is provided.

  Of these, the base portion 29 has a flat plate shape and is disposed on the inner side of the rotor 6. Further, mounting holes 33 and 33 for fixing the support 2b to a suspension device such as a knuckle are formed at both ends in the circumferential direction of the base portion 29. Similarly, the cylinder 28 is provided at a circumferential intermediate portion. Cylinder mounting holes 34 and 34 for supporting are formed. The inner arm portions 30a and 30b are provided so as to extend radially outward from both circumferential end portions of the base portion 29. The inner side surfaces of the inner side arm portions 30a and 30b are open to each other in the circumferential direction. In a state in which the parts are opposed to each other, a rectangular recess-shaped inner side torque receiving portion 35a and an outlet side inner torque receiving portion 35b are formed. The outer arm portions 31a and 31b are disposed on the outer side of the rotor 6, and the inner side surface in the circumferential direction has a rectangular concave shape with the openings facing each other in the circumferential direction. An outer torque receiving portion 36a and a delivery-side outer torque receiving portion 36b are formed. The connecting portions 32a and 32b are disposed so as to straddle the outer peripheral edge of the rotor 6 in the axial direction. The radially outer ends of the inner arm portions 30a and 30b and the outer sides of the inner side arm portions 30a and 30b. The arm portions 31a and 31b are connected to the radially outer ends. In addition, slide holes 37a and 37b that open to the inner side are formed in the connecting portions 32a and 32b, respectively. The outer bridge portion 27a connects the radially inner ends of the outer arm portions 31a and 31b in the circumferential direction.

The support 2b of this example having such a configuration is coupled and fixed to a suspension device such as a knuckle by bolts (not shown) screwed into the mounting holes 33 and 33.
In the case of this example, the rotor 6 rotates from the left to the right in FIG. 3 as indicated by an arrow α in FIG. 3 when the vehicle moves forward. Accordingly, the forward side in the forward movement state is the right side of FIG. 1 and the left side of FIGS. 2, 3 and 4, and the outlet side is the left side of FIG. 1 and the right side of FIGS. Moreover, in the following description, the inflow side and the outflow side are in the state at the time of advance unless otherwise indicated.

  The outer and inner pads 3b and 4b include a lining (friction material) 38, a metal back plate (pressure plate) 39 supporting the back surface of the lining 38, and a shim plate 40 attached to the back plate 39. It consists of and. In addition, a pair of rectangular projecting engagement protrusions 41a and 41b projecting in the circumferential direction are provided at the radial intermediate portions of both side edges of the back plate 39 in the circumferential direction. That is, among these engaging protrusions 41a and 41b, the engagement protrusion 41a on the turn-in side protrudes to the turn-in side at the radial intermediate portion of the edge on the turn-in side of the back plate 39. The engagement protrusion 41b on the delivery side is provided at the radial intermediate portion of the edge on the delivery side of the back plate 39 so as to protrude to the delivery side. Of these engaging protrusions 41a and 41b, the engaging protrusions 41a and 41a on the turn-in side are connected to the respective torque receiving portions 35a and 36a on the turn-out side and the engaging protrusions on the turn-out side. The pieces 41b and 41b are engaged with the outlet side outer and inner torque receiving portions 35b and 36b, respectively. As a result, the outer and inner pads 3b and 4b are supported in a state in which movement in the axial direction and movement in the radial and circumferential directions are restricted with respect to the support 2b.

In the case of this example, the engagement protrusions 41a and 41a on the turn-in side and the portions between the turn-out side outer and inner torque receiving portions 35a and 36a, and the engagement on the turn-out side Pad clips 42a and 42b are respectively interposed between the projecting pieces 41b and 41b and the outlet side outer and inner torque receiving portions 35b and 36b. These two pad clips 42a, 42b are formed by bending a metal plate having elasticity and corrosion resistance, such as stainless spring steel, and formed in a substantially U shape as a whole. The outer and inner pads 3b, 4b are arranged in the radial direction. The outer and inner pads 3b and 4b are prevented from rattling by elastically pressing (clamping) in the circumferential direction.
Although illustration is omitted, in order to separate the linings 38, 38 constituting the outer and inner pads 3b, 4b from the side surface of the rotor 6 with the release of braking, the outer and inner pads 3b Return springs formed by bending a spring steel wire material such as stainless steel or piano wire can also be provided on both sides in the circumferential direction of 4b. Note that the pad clips 42a and 42b and the return spring are not characteristic features of this example, and are described in detail in, for example, Patent Document 4 and the like, and thus further detailed description thereof is omitted here.

  The yoke 14a is formed of an iron-based alloy or an aluminum-based alloy by casting (including die-casting) or the like, or by using a non-metallic material such as carbon, and the entire shape is formed in an inverted U shape. The shape is such that the cylinder portion 9 is omitted from the caliper 5 of the first example. Such a yoke 14a is provided at the pressing portion 43 provided at the outer side end portion, the flat pressed portion 44 provided at the inner side end portion, and the axially intermediate portion. A bridge portion 45 connecting the pressed portion 44; In addition, a pair of arm portions 46a and 46b projecting in the circumferential direction are provided at both circumferential ends of the pressed portion 44, respectively. Both arm portions 46a and 46b are formed with through holes 47 and 47 penetrating in the axial direction, respectively. Further, a substantially rectangular window portion 49 penetrating in the radial direction is formed in the inner half of the intermediate portion in the circumferential direction of the bridge portion 45.

  The yoke 14a having such a configuration is supported so as to be movable in the axial direction with respect to the support 2b. For this reason, in the case of this example, the pair of bolts 50a and 50b inserted through the through holes 47 and 47 from the outer side are connected to the base end portions (inner side end portions) of the pair of slide pins 51a and 51b. The slide pins 51a and 51b are coupled and fixed to the both arm portions 46a and 46b by screwing them into the screw holes 52 and 52 that are opened in (2). And the front-end | tip part thru | or intermediate | middle part of these both slide pins 51a and 51b are slidably inserted in the slide holes 37a and 37b formed in both the connection parts 32a and 32b which comprise the said support 2b. Of the slide pins 51a and 51b, portions exposed to the outer side from the slide holes 37a and 37b are covered with dust boots 53a and 53b, respectively.

  The cylinder 28 is formed, for example, by casting an aluminum alloy (including die-casting), for example, so as to be substantially cylindrical. The cylinder body 54 and the outer peripheral surface of the cylinder body 54 are formed. A mounting flange portion 55 provided so as to project radially inward from the outer side end portion, and a piping port 56 and a bleeder 57 provided at an axially intermediate portion of the outer peripheral surface of the cylinder body 54 are provided. The cylinder body 54 has cylinder spaces 58 that are open on both sides in the axial direction for fitting the first and second pistons 18a and 19a therein. Further, through holes 59, 59 penetrating in the axial direction are formed at both ends in the circumferential direction of the mounting flange portion 55. The piping port 56 communicates with the cylinder space 58 (a hydraulic chamber 20a described later), and is used for supplying and discharging brake fluid pressure. The bleeder 57 is used to remove air from the cylinder space 58. In addition, seal grooves 61a and 61b having a rectangular cross section are formed on the outer and inner portions of the inner peripheral surface of the cylinder body 54, respectively. The first seal member 62 and the second seal member 63 each having an annular shape are mounted in the seal grooves 61a and 61b. Of the inner peripheral surface of the cylinder body 54, the outer side end portion (outer side opening portion) and the inner side end portion (inner side opening portion) have large diameter grooves 64a and 64b having larger inner diameters, respectively. Is forming. And the 1st dust cover 65 and the 2nd dust cover 66 are mounted in these both large diameter grooves 64a and 64b.

  The cylinder 28 having such a configuration is detachably attached to the support 2b and detachably coupled to the support 2b. For this reason, in the case of this example, a pair of bolts 60, 60 for fixing the cylinder inserted through the through holes 59, 59 are connected to a cylinder mounting hole 34 formed in the base 29 constituting the support 2b. , 34 are fixed with screws. In this state, the cylinder 28 is disposed on the inner side of the inner pad 4b, and is disposed on the inner side of the window portion 49 of the bridge 45 constituting the yoke 14a. Therefore, the cylinder 28 is exposed when the floating type disc brake 1b of this example is viewed from the outside in the radial direction.

  Each of the first and second pistons 18a and 19a is formed in a bottomed cylindrical shape, and is fitted in the cylinder space 58 in a liquid-tight manner so as to be movable in the axial direction (moving in directions opposite to each other). Has been. Specifically, the first piston 18a is composed of a cylindrical portion 67a and a bottom portion 68a. The bottom portion 68a of the first piston 18a faces the outer side, and is fitted into the inner half of the cylinder space 58. Disguise. The second piston 19a includes a cylindrical portion 67b and a bottom portion 68b. The bottom portion 68b of the second piston 19a faces the inner side, and is fitted to the outer half of the cylinder space 58. Yes. As a result, a space formed between the bottom portions 68a and 68b in the cylinder space 58 is defined as a hydraulic chamber 20a. In addition, a space between the outer peripheral surface of the first piston 18a and the outer portion of the inner peripheral surface of the cylinder body 54 is sealed by the first seal member 62, and the outer peripheral surface of the second piston 19a and the cylinder are sealed. A space between the inner peripheral surface of the main body 54 and the inner portion is sealed by the second seal member 63. The outer opening of the cylinder body 54 is closed by the first dust cover 65, and the inner opening of the cylinder body 54 is closed by the second dust cover 66. Further, with the first and second pistons 18a and 19a fitted in the cylinder space 58 in a liquid-tight manner, the tip of the first piston 18a is opposed to the inner side surface of the inner pad 4b. The tip of the second piston 19a is opposed to the outer side surface of the pressed portion 44 that constitutes the yoke 14a. In the case of this example, the first piston 18a and the second piston 19a are the same parts, and cost reduction is achieved by sharing parts.

  In order to perform braking by the floating disc brake 1 b of this example, pressure oil is introduced into the hydraulic chamber 20 a through the piping port 56. Thereby, the first piston 18a and the second piston 19a are moved in directions away from each other in the axial direction. Then, the inner piston 4b is pressed against the inner side surface of the rotor 6 from the right to the left in FIG. 5 by the first piston 18a. At the same time, the pressed portion 44 is pressed from the left to the right in FIG. 5 by the second piston 19a, and the yoke 14a is moved to the right in FIG. 5 with respect to the support 2b. Thereby, the outer pad 3b is pressed against the outer side surface of the rotor 6 from the left to the right in FIG. As a result, the rotor 6 is strongly clamped from both sides in the axial direction, and braking is performed.

  On the other hand, when releasing the brake, the pressure oil is discharged from the hydraulic chamber 20a. The first piston 18 a is pulled back (rolled back) into the cylinder space 58 by the elasticity of the first seal member 62. Similarly, the second piston 19 a is pulled back into the cylinder space 58 by the elasticity of the second seal member 63.

According to the floating type disc brake 1b of the present example having the above-described configuration, it is possible to suppress dragging of the outer and inner pads 3b and 4b, and to reduce cost and weight.
That is, in this example, as described above, the first and second pistons 18a and 19a can be pulled back into the cylinder space 58 when the brake is released. For this reason, it is possible to secure a sufficient clearance between the linings 38 and 38 of the outer and inner pads 3 b and 4 b and the side surface of the rotor 6. Therefore, according to the floating type disc brake 1b of this example, the occurrence of dragging of the outer and inner pads 3b and 4b can be effectively suppressed.

Particularly in the case of this example, the cylinder 28 is configured separately from the support 2b, and the cylinder 28 is detachably supported with respect to the support 2b. In addition to the above effects, the following effects are obtained. Can be obtained.
First, the replacement work of the pads 3b and 4b can be performed with the cylinder 28 removed from the support 2b. Accordingly, as a support structure for the outer and inner pads 3b and 4b with respect to the support 2b, a structure that engages in the radial direction (in the case of the second example of the conventional structure) and a structure that uses pad pins are not used. As in the first example of the structure, the rectangular convex engaging protrusions 41a and 41b, which are widely used in floating disc brakes having one piston, are connected to rectangular concave torque receiving portions 35a and 35b (36a, It is possible to adopt a structure that engages 36b) in the axial direction. As a result, as in the structure of this example, pad clips 42a and 42b for suppressing rattling of the outer and inner pads 3b and 4b are used so as not to affect the sliding resistance of the yoke 14a. it can. Therefore, the occurrence of drag can be effectively suppressed as compared with the second example of the conventional structure. Further, as compared with the case where pad pins are used, the restriction on the thickness dimension in the radial direction of the bridge portion 45 constituting the yoke 14a can be reduced (thickness can be increased). Therefore, the degree of freedom in selecting the material of the yoke 14a is improved (it is possible to use a light material with low strength but low strength), which is advantageous in reducing the weight of the yoke 14a.

  Further, the support 2b and the outer and inner pads 3b and 4b constituting the floating type disc brake 1b of the present example are the floating type disc having one piston as shown in the first example of the conventional structure described above. Common use is possible between the support and the pad used for the brake. This is advantageous in reducing costs. When used as a floating type disc brake having such a single piston, the cylinder mounting holes 34, 34 formed in the support 2b remain open. Further, according to the floating type disc brake 1b of this example, various cylinders having different cylinder diameters can be attached to and exchanged with respect to the support 2b. Therefore, between the floating type disc brakes having different cylinder diameters, The support 2b (and pads 3b and 4b) can be shared, and the cost can be further reduced. Furthermore, since only the operation of attaching the first and second pistons 18a and 19a and the first and second seal members 62 and 63 (sub-assembly operation) to the cylinder 28 is performed in the clean room, The work target parts to be performed can be reduced in size. Therefore, it is possible to save space in the clean room.

  In the case of this example, the outer bridge portion 27a is provided on the outer side portion of the support 2b. However, since the cylinder 28 is separated from the support 2b, the inner peripheral surface of the cylinder 28 is provided. This eliminates the interference between the tool used for the machining and the outer bridge portion 27a. Accordingly, the degree of freedom regarding the shape and the installation position of the outer bridge portion 27a can be improved.

In the case of this example, since the cylinder 28 can be made of an aluminum alloy having a lower strength than the support 2b, the cylinder 28 is made of an iron-based material such as cast iron, which is the same as the support 2b. Compared to the case of making from an alloy, cost and weight can be reduced.
About another structure and an effect, it is the same as that of the case of the 2nd example of embodiment mentioned above.

[Second Example of Embodiment]
A second example of the embodiment of the present invention will be described with reference to FIG. The floating type disc brake 1c of this example is characterized in that the electric motor 69 is used to move both the first and second pistons 18b and 19b fitted in the cylinder 28a in the axial direction. Since other configurations and operational effects are basically the same as in the case of the first example of the above-described embodiment, illustration and description of overlapping portions are omitted, and hereinafter, characteristic portions of this example Will be explained.

  In the case of this example, the electric motor 69 is attached to the outer peripheral surface of the cylinder 28a. Also, a conversion of a ball screw mechanism or the like for converting the rotational movement of the output shaft of the electric motor 69 into a linear movement in a portion of the cylinder space 58a between the first and second pistons 18b and 19b. A mechanism 70 is provided. Then, the first and second pistons 18b and 19b are axially moved by moving a pair of linear motion members constituting the conversion mechanism 70 to both sides in the axial direction based on energization to the electric motor 69. It is possible to move to. In other words, in the case of this example, the first and second pistons 18b and 19b are mechanically moved in the axial direction using the electric motor 69 instead of the hydraulic pressure.

In the case of this example having the above-described configuration, the first and second pistons 18b and 19b are moved to the cylinder space 58a by rotating the electric motor 69 in reverse to that during braking when releasing the brake. It can be pulled back in. Therefore, even in this example, the occurrence of drag can be effectively suppressed. In the case of this example, the heavy electric motor 69 and the conversion mechanism 70 are installed around and inside the cylinder 28a supported by the support 2b, not the yoke 14b that moves in the axial direction during braking. Therefore, it is not necessary to increase the sliding resistance of the yoke 14b, which leads to deterioration of the dragging of the outer and inner pads 3b and 4b.
About another structure and an effect, it is the same as that of the case of the 1st example of the said embodiment.

[Third example of embodiment]
A third example of the embodiment of the present invention will be described with reference to FIGS. The feature of this example is that the cylinder 28b is supported with respect to the support 2b so that a slight displacement is possible. Since the configuration and operational effects of the other parts are the same as in the case of the first example of the above-described embodiment, the overlapping description and illustration are omitted, and the following description will focus on the characteristic parts of this example. .

  In the case of this example, an elastic material such as rubber having both inner and outer peripheral surfaces supported by a pair of synthetic resin collars 87a and 87b in a through hole 59 formed in the mounting flange portion 55 of the cylinder 28b. A cylindrical bush 71 made of steel is fitted inside. A pair of arc-shaped concave portions 72 and 72 that are recessed in the axial direction are formed on both end surfaces of the bush 71 in the axial direction. The bolt 60 inserted through the inside of the bush 71 is screwed and fixed to the cylinder mounting hole 34 formed in the support 2b. In the case of this example, in order to prevent the bush 71 (and the collars 87a, 87b) from falling out from the through hole 59 to the inner side, the bush 71 and the head of the bolt 60 are interposed. A washer 73 is interposed. The recesses 72, 72 formed in the bush 71 exhibit a function of making the cylinder 28b easy to displace by appropriately reducing the rigidity of the bush 71.

  In the case of this example having such a configuration, the linings 38 and 38 constituting the outer and inner pads 3b and 4b (see FIG. 5 and the like) are fitted into the cylinder 28b due to uneven wear. When the postures of the first and second pistons 18a (19a) are tilted, the bush 71 is elastically deformed to follow the tilts of the first and second pistons 18a (19a). The cylinder 28b can be slightly displaced (tilted) with respect to the support 2b. Therefore, in the case of this example having such a configuration, it is possible to effectively prevent the inner peripheral surface of the cylinder body 54 from being damaged (twisted) by the first and second pistons 18a (19a). .

FIG. 12 shows another example of the support structure that can obtain the same effect (the effect of allowing the displacement of the cylinder 28b) as the structure shown in FIGS. Hereinafter, the eight examples shown in FIG. 12 will be briefly described with a focus on the differences from the structure shown in FIGS.
First, in the case of the structure shown in (A), a pair of collars is omitted, the entire length in the axial direction of the bush 71a is extended, and both end portions in the axial direction of the bush 71a are protruded from the through holes 59. . Then, outwardly projecting flange portions 74 and 74 having outer diameter dimensions larger than those of the other portions are provided in the protruding portions, respectively. According to such a structure, the outward flange portions 74 and 74 can be interposed between the bolt 60 and the base portion 29 and the mounting flange portion 55. For this reason, it can prevent that each of these members contact | abut directly, and it becomes easy to ensure the displacement amount of the cylinder 28b large. Further, the cost of the support structure can be reduced and the assembling work can be simplified as the number of parts is reduced.

  In the case of the structure shown in (B), instead of the bolt 60 used in the structure of (A), a stud bolt 75 in which male thread portions are formed on the outer peripheral surfaces of both axial ends is used. A nut 76 is screwed into the male screw portion of the inner side portion of the stud bolt 75.

  In the case of the structure shown in (C), instead of the stud bolt 75 used in the structure of (B), a stud bolt in which a serration portion is formed on the outer peripheral surface of the outer side portion instead of a male screw portion. 75a is used. Further, the cylinder mounting hole 34a formed in the support 2b is not a screw hole in which an internal thread is formed on the inner peripheral surface, but merely a through hole. The stud bolt 75a is fixed to the support 2b by press-fitting the serration portion of the stud bolt 75a into the cylinder mounting hole 34a.

  In the case of the structure shown in (D), the stud bolt 75b has a longer overall length than the structure in (C), and the outer peripheral surface of the inner side portion is a simple cylindrical surface. Further, the nut 76 and the washer 73 used in the structure of (C) are omitted.

  In the case of the structure shown in (E), annular concave grooves 77a and 77b are formed around the through hole 59 on both side surfaces in the axial direction of the mounting flange portion 55a. A pair of bushes 71b and 71b are mounted in the annular concave grooves 77a and 77b, respectively.

  In the case of the structure shown in (F), a ball joint 78 is used instead of the bolt 60 used in the structure of (A). That is, the male thread portion formed at the base of the ball joint 78 is screwed and fixed to the cylinder mounting hole 34, and the head 79 of the ball joint 78 is fitted inside the bush 71a with the bush 71a elastically deformed. Yes. Further, an extension shaft 80 provided at the tip of the head 79 protrudes from the through hole 59 toward the inner side. According to the structure of (F) having such a configuration, the work for supporting the cylinder 28b with respect to the support 2b can be performed by elastically pushing the head 79 into the bush 71a. Work can be facilitated.

  In the case of the structure shown in (G), the ball joint 78a and the spring 81 are used without using the bush, and the through hole 59a formed in the mounting flange portion 55b has a large diameter on the inner side half. It is comprised from the part 82 and the small diameter part 83 of the outer side half part. The male screw portion provided at the base portion of the ball joint 78a is fixed to the cylinder mounting hole 34 with screws. In addition, the neck portion of the ball joint 78a is disposed inside the small diameter portion 83, and the receiving portion 84 that houses the head in a displaceable manner is disposed inside the large diameter portion 82. Further, the spring 81 is elastically compressed between the outer side surface of the mounting flange portion 55b and the inner side surface of the base portion 29 in a state where the spring 81 is disposed around the base end side portion of the ball joint 78a. In the illustrated structure, the spring 81 is a coil, but a substantially U-shaped leaf spring can also be used.

In the case of the structure shown in (H), a stepped annular concave groove 77c is formed around the through hole 59 in the outer side surface of the mounting flange 55c. Further, an annular convex portion 85 protruding toward the inner side is formed around the cylinder mounting hole 34 in the inner side surface of the base portion 29a. Then, the spring 81a is arranged with the outer side end portion fitted on the annular convex portion 85 and the inner side end portion fitted on the annular concave groove 77c. Further, the bolt 60 is screwed and fixed to the inside of the spring 81a through a sleeve 86 having an outward flange at the inner end. According to such a configuration, the spring 81a can provide appropriate elasticity not only when the cylinder 28b is displaced in the axial direction with respect to the support 2b but also when the cylinder 28b is displaced in the radial direction.
About another structure and an effect, it is the same as that of the case of the 1st example of the said embodiment.

  In carrying out the present invention, the number of cylinders constituting the floating type disc brake is not limited to one, and two may be provided as in the second example of the conventional structure described above, or more. It may be provided. Further, as a driving means for driving a pair of pistons fitted in the cylinder, various other structures such as a pneumatic type as well as a mechanical type using a hydraulic pressure or an electric motor can be adopted. In addition, the structures of the examples of the embodiment of the present invention can be implemented in appropriate combination.

1, 1a, 1b, 1c Floating disc brake 2, 2a, 2b Support 3, 3a, 3b Outer pad 4, 4a, 4b Inner pad 5 Caliper 6 Rotor 7 Caliper claw 8 Piston 9 Cylinder part 10 Bridge part 11 Slide pin 12 Slide Hole 13 Seal member 14, 14a Yoke 15 Support body 16 Cylinder portion 17 Cylinder space 18, 18a, 18b First piston 19, 19a, 19b Second piston 20, 20a Hydraulic chamber 21 Slide pin 22 Pressing portion 23 Pressed portion 24 Bridge Part 25 First seal member 26 Second seal member 27, 27a Outer bridge part 28, 28a, 28b Cylinder 29, 29a Base part 30a, 30b Inner side arm part 31a, 31b Outer side arm part 32a, 32b Connecting part 33 Installation 34, 34a Cylinder mounting hole 35a Inlet side inner torque receiving part 35b Outlet side inner torque receiving part 36a Inlet side outer torque receiving part 36b Outlet side outer torque receiving part 37a, 37b Slide hole 38 Lining 39 Back plate 40 Shim plate 41a, 41b Engagement protrusions 42a, 42b Pad clip 43 Pressing part 44 Pressed part 45 Bridge part 46a, 46b Arm part 47 Through hole 49 Window part 50a, 50b Bolt 51a, 51b Slide pin 52a, 52b Screw hole 53a, 53b Dust boot 54 Cylinder body 55, 55a, 55b Mounting flange portion 56 Piping port 57 Bleeder 58 Cylinder space 59, 59a Through hole 60 Bolt 61a, 61b Seal groove 62 First seal member 63 Second seal member 64a, 64b Large diameter groove portion 65 First dust cover 66 Second dust cover 67a, 67b Cylindrical portion 68a, 68b Bottom 69 Electric motor 70 Conversion mechanism 71, 71a, 71b Bush 72 Recess 73 Washer 74 Outward flange 75, 75a, 75b Stud bolt 76 Nut 77a, 77b, 77c Annular recess Groove 78 Ball joint 79 Head 80 Extension shaft portion 81, 81a Spring 82 Large diameter portion 83 Small diameter portion 84 Receiving portion 85 Annular convex portion 86 Sleeve 87a, 87b Collar 88a, 88b Locking convex portion 89a, 89b Locking convex portion 90a , 90b Engagement part

Claims (7)

A support fixed to the vehicle body adjacent to a rotor that rotates with the wheels;
An outer pad and an inner pad which are arranged on both sides in the axial direction of the rotor and supported in a state in which movement in the axial direction is restricted with respect to the support and movement in the radial direction and the circumferential direction is restricted;
A pressing part for pressing the outer side surface of the outer pad to the outer side end part, a pressed part to the inner side end part, and a bridge part for connecting the pressing part and the pressed part to the intermediate part in the axial direction, respectively. A yoke supported so as to be movable in the axial direction with respect to the support;
A cylinder that is disposed on the inner side of the inner pad and has cylinder spaces that are open on both sides in the axial direction;
A first piston that is fitted in the cylinder space so as to be movable in the axial direction, presses the inner side surface of the inner pad during braking, and a second piston presses the outer side surface of the pressed portion during braking;
Floating disc brake with
A floating type disc brake characterized in that the cylinder configured separately from the support is detachably supported with respect to the support.   The floating type disc brake according to claim 1, wherein the cylinder is fixedly coupled to the support so as not to be displaced.   The floating type disc brake according to claim 1, wherein the cylinder is supported so as to be slightly displaceable with respect to the support.   Convex engaging protrusions provided on both side edges of the outer and inner pads in the circumferential direction face the outer side and inner side parts of both ends of the support in the circumferential direction. Any one of claims 1 to 3 engaged with a concave torque receiving portion provided in a state that allows movement in the axial direction and restricts movement in the circumferential direction and the radial direction. The floating type disc brake described in item 1.   5. The floating disc brake according to claim 4, wherein an outer bridge portion that connects the outer side torque receiving portion and the outlet side torque receiving portion in the circumferential direction is provided at an outer side portion of the support. .   The floating disk brake according to any one of claims 1 to 5, wherein the support and the cylinder are made of different materials.   The floating disc brake according to any one of claims 1 to 6, wherein the first and second pistons are driven by driving means other than hydraulic pressure.

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