JP6277514B2 - Disc brake device - Google Patents

Description

  The present invention relates to a disc brake device, and more particularly to a disc brake device of a type that generates a braking force during non-operation, which is called a negative type.

  Conventionally, in a negative type disc brake device, a spring mechanism (actuating spring) is employed as a power source for generating a pressing force, and a hydraulic mechanism is employed as a release mechanism (Patent Document 1). On the other hand, the applicant of the present application has considered using a mechanical force as a release mechanism, and tried to adopt a cam mechanism as disclosed in Patent Document 2 as a mechanism for releasing the pressing force. The disc brake device disclosed in Patent Document 3 has been devised. Note that the cam mechanism disclosed in Patent Document 2 is a mechanism for generating a braking force.

  The disc brake device disclosed in Patent Document 3 is a device provided with a small floating caliper composed of a body main body, a claw portion, and a bridge portion connecting the two. In the disc brake device, a cam shaft for operating the cam mechanism is protruded from the body main body on the extension line of the bridge portion.

Japanese Patent Laid-Open No. 52-113187 JP 2011-271132 A Japanese Patent Application No. 2013-110246

  The disc brake device that releases the pressing force of the operating spring by the cam mechanism disclosed in Patent Document 3 has various advantageous effects such as downsizing, simplification of incidental equipment, and improvement in maintenance.

  However, in the disc brake device configured as disclosed in Patent Document 3, a through hole for projecting the camshaft is provided in the back meat portion positioned on the extension line of the bridge portion. A new problem such as a decline occurred.

  Specifically, as shown in FIG. 7, since the reaction force of the claw portion acts on the back meat portion, when the rigidity of the portion decreases, when the force is applied in the axial direction of the rotor, the body There is a possibility that an opening between the main body and the claw portion becomes large.

  If the structure of the caliper body is configured to provide a plurality of bridge portions (in Patent Document 2, two locations on the return side and the return side of the rotor) as in the disc brake device disclosed in Patent Literature 2, It is considered that the caliper body can be kept rigid even when a through hole is provided in the back meat portion. In this case, however, the caliper body may be enlarged.

  Therefore, in the present invention, even when a cam mechanism is adopted as a mechanism for releasing the pressing force generated by the operating spring, the caliper body is reduced in size and does not reduce the rigidity to the force in the axial direction of the rotor. An object is to provide a brake device.

In order to achieve the above object, a disc brake device according to the present invention is configured such that a piston disposed in a cylinder formed in a caliper body receives a pressing force from an operating spring, so that a brake pad is attached via one end face. In the disc brake device to be pressed, a reaction force for releasing the pressing force against the piston is generated by inputting a rotational force, the piston is pushed back, and the pressing force is received when the input of the rotational force is released. The shaft center of the camshaft having the cam portion that is pushed back to the initial position is arranged so as to avoid the range of the back portion located on the extension line of the bridge portion in the caliper body.

  Further, in the disc brake device having the above-described characteristics, at least a part of the camshaft passes through the center of the cylinder, and the shaft center is parallel to both the arrangement surface of the back portion and the arrangement surface of the brake pad. It is desirable to have a configuration that is arranged as follows.

  According to such a configuration, there is almost no influence on the reaction force from the claw portion. Moreover, the weight balance on the inflow side and the outflow side of the rotor can be kept good.

  According to the disc brake device having the above-described features, even when the cam mechanism is employed as a mechanism for releasing the pressing force generated by the operating spring, the caliper body is downsized with the bridge portion as one place, It can suppress that the rigidity to the force with respect to the axial direction of a rotor falls.

It is a figure showing the side composition of the disc brake device concerning an embodiment. It is a figure which shows the AA cross section in FIG. It is a figure which shows the BB cross section in FIG. It is a fragmentary sectional enlarged view for demonstrating the relationship between a cam shaft and a connecting rod. It is a schematic diagram of the caliper body which shows the A'-A 'cross section in FIG. It is a schematic diagram for demonstrating the relationship of the force added to a caliper body. It is a schematic diagram for demonstrating that when the through-hole is provided in the back meat part and the force with respect to the axial direction of a rotor is applied, the rigidity of a back meat part is influenced.

  Hereinafter, embodiments of the disc brake device according to the present invention will be described in detail with reference to the drawings. 1 is a side view of the disc brake device according to the first embodiment, and FIG. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a view showing a BB cross section in FIG. FIG. 4 is an enlarged partial cross-sectional view for explaining the relationship between the camshaft and the connecting rod.

  The disc brake device 10 according to the present embodiment is basically configured to have a caliper body 12, an inner pad 60, an outer pad 62, and an air chamber 50, and is supported by a fixing portion (not shown) via a support 66.

  The caliper body 12 basically has a body main body 14, a claw portion 18, and a bridge portion 16. The body main body 14 includes a cylinder 20, a bore 22, and a bearing hole 24 inside. A piston 26 is disposed in the cylinder 20, and an operating spring 28 and a guide 30 are disposed in the bore 22.

  The piston 26 slides in the cylinder 20 and plays a role of pressing an inner pad 60 disposed between the claw portion 18 described later by one end face. The piston 26 according to the embodiment has a through hole 26a in a direction orthogonal to the pressing direction. Further, an axial hole 26b penetrating the side wall of the through hole 26a is formed on the other end face of the piston 26.

  The actuating spring 28 is an element that generates a pressing force that presses the piston 26 in the arrangement direction (pressing direction) of the inner pad 60. A specific configuration of the operating spring 28 can be a disc spring. This is because the disc spring is suitable as a pressing force generating means for generating a braking force because a large load can be applied with a small deflection. In addition, when employ | adopting a disc spring, it is good to set it as the structure arrange | positioned so that several disc springs may be piled up alternately.

  The end of the bore 22 opposite to the connecting end with the cylinder 20 is a release end, and a plug 32 serving as a spacer for adjusting the thickness and pressing force of the operating spring 28 is disposed here. By adopting such a configuration, it is possible to change the deflection and thickness of the actuating spring 28 (if a disc spring is employed, the number of the springs), and the like, and the pressing force can be adjusted. In the present embodiment, the plug 32 has a male screw portion that can be screwed into a female screw portion formed at the open end of the bore 22, and is positioned by tightening the male screw portion. The plug 32 is sealed by a fastening plate 34 that is a cover that covers the open end of the bore 22. In addition, the plug 32 according to the embodiment has a through hole 32a at the center, and the slider 31a of the adjuster 31 in the guide 30, which will be described in detail later, is configured to be slidable.

  The guide 30 is a transmission element that transmits a pressing force by the operating spring 28 to the piston 26 and receives a reaction force by a camshaft 36 to be described in detail later. The guide 30 according to the embodiment has a convex portion 30a and a flange portion 30b in appearance. When the disc spring is adopted as the operating spring 28, the outer shape of the convex portion 30a is formed to be slightly smaller than the diameter of the center hole formed in the disc spring. Further, the flange portion 30b is formed at one end of the convex portion 30a so as to protrude to the outer peripheral side from the outer shape of the convex portion 30a, and serves as an element that receives the pressing force by the operating spring 28. Moreover, the recessed part 30c which formed the bottom face in the hemispherical shape is provided in one edge part of the guide 30, ie, the flange part 30b formation side edge part.

  The other end of the guide 30 is provided with a recess in which a female screw is formed, and the adjuster 31 can be screwed into the recess. The adjuster 31 plays a role of adjusting the thickness of the operating spring 28 and the height of the guide 30, and a slider 31 a protrudes from an end surface facing the plug 32. The slider 31a is an element slidable in a through hole 32a formed in the plug 32, and bears the positioning action of the guide 30 in the axial direction.

  In this embodiment, the guide 30 having such a configuration is arranged such that the convex portion 30a penetrates the center hole of the disc springs (actuating springs 28) arranged in a stacked manner. By adopting such an arrangement form, it is possible to prevent the disc springs arranged in a stacked manner from shifting in the radial direction.

  A cam shaft 36 is disposed in the bearing hole 24. The camshaft 36 is configured based on a rotating shaft 36a and a large diameter portion 36b. In the camshaft 36 according to the embodiment, a rotation shaft 36a is provided so as to penetrate the large diameter portion 36b. Further, as shown in FIG. 4, the large-diameter portion 36b of the camshaft 36 according to the embodiment is configured such that the connecting rod 42 is in sliding contact with a concave cam portion 36c having an arcuate bottom portion. In the cam mechanism having such a configuration, it is possible to generate a force in a direction orthogonal to the rotation shaft 36a due to the rotation of the rotation shaft 36a by changing the thickness of the arc-shaped bottom portion.

  The bearing hole 24 is a hole disposed in a direction orthogonal to the direction in which the cylinder 20 of the body main body 14 is formed. Further, in the disc brake device according to the present embodiment, the bearing hole 24 is arranged so as to avoid the range of the width W of the back portion of the caliper body 12. Here, the back meat part is a part that transmits a force acting in the axial direction of the rotor in the bridge part 16 and the body main body 14. Specifically, it is a part to which the reaction force from the claw part 18 is transmitted, and as shown in FIG. 5, a part of the body body 14 located on the bridge part 16 and an extension line of the width of the bridge part 16. . When the bearing hole 24 is provided within the range of the width W of the back portion, the rigidity of the portion of the caliper body 12 to which the force acting in the axial direction is transmitted is reduced. For this reason, when an axial reaction force is applied during braking, the caliper body 12 is greatly bent, and the caliper body 12 is enlarged if the bending is to be suppressed.

  For this reason, the bearing hole 24 is formed so that the shaft center of the camshaft 36 is positioned in the range A shown in FIG. By setting the formation range of the bearing hole 24 in such a range, it is possible to make it less susceptible to the reaction force from the claw portion 18 as shown in FIG. In this embodiment, at least a part of the camshaft 36 passes through the center of the cylinder 20, and the axial center thereof is parallel to both the arrangement surface of the back portion and the arrangement surface of the inner pad 60. Is forming. This is because the bearing hole 24 having such an arrangement form can be hardly affected by the reaction force.

  The camshaft 36 disposed in the bearing hole 24 is disposed such that the rotation shaft 36 a passes through the through hole 26 a formed in the piston 26. By adopting such an arrangement, the camshaft 36 also serves as a rotation stop for the piston 26. The inner pad 60 pressed by the piston 26 is caused to rotate by a couple generated during braking. For this reason, a rotational force is also applied to the piston 26 that is in contact with the inner pad 60 during braking. When the piston 26 rotates, an unspecified force acts on a boot, a seal, or an operating spring 28 disposed between the cylinder 20 and the piston 26. Therefore, by inhibiting the rotation of the piston 26, breakage or malfunction of these elements can be prevented.

  In addition, one end of the rotation shaft 36 a is exposed to the outside of the body main body 14 from the opening of the bearing hole 24, and a rotation operation can be imparted from the outside of the body main body 14. The large-diameter portion 36 b constituting the camshaft 36 is disposed and formed so as to be positioned inside the through hole 26 a of the piston 26 in the state of being disposed in the bearing hole 24. A gap is provided between the through hole 26a and the large diameter portion 36b so that the large diameter portion 36b and the inner wall surface of the through hole 26a do not contact when the piston 26 moves in the axial direction. .

  In addition, the hole diameter of the bearing hole 24 is formed to be sufficiently larger than the rotating shaft 36a because of the necessity of inserting the large diameter portion 36b therein. For this reason, by interposing the shaft holder 38 between the inner wall of the bearing hole 24 and the rotary shaft 36a, it is possible to exert both effects of preventing the camshaft 36 from coming off and preventing rattling.

  Between the cam portion 36c of the large diameter portion 36b of the camshaft 36 disposed in the through hole 26a of the piston 26 and the concave portion 30c of the guide 30 that receives the pressing force of the operating spring 28, an axial hole 26b is interposed. A connecting rod 42 is arranged. With such an arrangement, the contact portion between the cam portion 36c and the connecting rod 42 changes as the large-diameter portion 36b rotates as the rotating shaft 36a rotates. With this action, a part of the connecting rod 42 is pushed out from the axial hole 26b to generate a reaction force that pushes back the guide 30. Thereby, the pressing force of the operating spring 28 is released, and the urging force of the inner pad 60 against the rotor is also released. At this time, the pressing force of the operating spring 28 is received by the inner peripheral wall of the bearing hole 24, that is, the body main body 14 via the rotating shaft 36 a of the camshaft 36, so that reaction force can be generated.

  Here, as shown in FIG. 2, the piston 26 according to the embodiment is coupled to the guide 30 via a coupling pin 44. For this reason, when the guide 30 is pushed back to the arrangement side of the operating spring 28 by the connecting rod 42, the piston 26 is also pulled back. Thereby, drag of the inner pad 60 pressed against the rotor by the piston 26 can also be prevented.

  Further, the camshaft 36 is arranged and configured such that the rotation center O1 of the rotary shaft 36a is deviated from the extended line of the straight line L passing through the axis of the connecting rod 42. For this reason, when the rotational force with respect to the camshaft 36 is released, the connecting rod 42 transmits the pressing force of the operating spring 28 to the cam portion 36c, and the cam portion 36c is moved to a predetermined initial position (a cam formed in a concave shape). It will push back to the position where the thickness of the bottom face of the part 36c becomes thin.

In order to realize the operation as described above, it is necessary to make it possible to apply a rotational force to the rotating shaft 36a of the camshaft 36. For this reason, one end of the cam lever 46 is attached to an exposed portion of the rotating shaft 36a of the camshaft 36 from the bearing hole 24. Here, the booster mechanism constituted by the cam mechanism including the camshaft 36 and the connecting rod 42 and the cam lever 46 is a distance l ₁ from the center O1 of the rotating shaft 36a as the fulcrum to the center O3 of the pin as the power point. (See FIG. 1), the lever ratio (l ₁ / l ₂ ) is based on the ratio of the distance l ₂ from the center O1 of the rotating shaft 36a as the fulcrum to the arc center O2 of the connecting rod 42 as the action point. Determined. For this reason, by making the effective length l ₁ of the cam lever 46 longer than l ₂ , a large force can be obtained with a small operating force. Therefore, it is possible to generate a reaction force that pushes back the guide 30 against the pressing force of the operating spring 28 that generates a large load.

  The other end of the cam lever 46 is connected to a linear rod 48 that is operated by the air chamber 50. By connecting a linearly acting rod 48 that moves linearly by the operation of the air chamber 50 to the other end of the cam lever 46, the rotation of the rotating shaft 36a of the camshaft 36 is rotated by the linear motion that occurs by the operation of the air chamber. It can be converted into rotational motion. When the cam lever 46 is rotated, even if the rotation angle is small, the trajectory is slightly arcuate. For this reason, by connecting the cam lever 46 and the linearly acting rod 48 through pin coupling via the clevis 52, distortion due to a difference in the movement trajectory can be absorbed.

  The claw portion 18 is a reaction force receiver that faces the body main body 14, and is configured such that the outer pad 62 can be disposed at a position facing the inner pad 60. The claw portion 18 in the embodiment is provided with a through hole 18a from the outer surface of the claw portion 18 toward the inner surface on which the outer pad 62 is disposed. The through-hole 18a is subjected to female threading at least on the outer surface side. An adjuster bolt 64 can be disposed in the through-hole 18a, and the axial direction of the rotor of the outer pad 62 (actually supported by a support 66 described in detail later) assembled to the inner surface of the claw 18 is provided. The position can be adjusted.

  Since the pressing force of the disc brake device 10 according to the embodiment is generated by the displacement of the operating spring 28, the sliding amount (protruding amount) of the piston 26 is small. For this reason, the clearance for the pad wear can be adjusted by tightening the adjuster bolt 64. The bridge portion 16 is a connecting portion that connects the body main body 14 and the claw portion 18.

  The caliper body 12 having the above-described configuration is assembled to the support 66 via guide pins 68 arranged in parallel with the axial direction of the rotor. With such a configuration, the caliper body 12 can slide in the axial direction of the rotor with the support 66 as a base point. Note that the inner pad 60 and the outer pad 62 are supported by the torque receiving portion of the support 66 so as to be slidable in the axial direction of the rotor.

  In the disc brake device 10 configured as described above, the bearing hole 24 for arranging the camshaft 36 constituting the cam mechanism is arranged to avoid the range of the width W of the back portion of the caliper body 12. . Therefore, it is possible to configure the disc brake device 10 that does not have insufficient rigidity against the reaction force from the claw portion 18 while making the caliper body 12 small.

Next, the operation of the disc brake device 10 configured as described above will be described.
First, when the air chamber 50 is not in operation, the guide 30 and the piston 26 are pressed by the pressing force of the operating spring 28, and the piston 26 is pushed out to the rotor side. In this state, the inner pad 60 is pushed out to the rotor side by receiving a pressing force from the piston 26 and urges the rotor. When the inner pad 60 is urged to the rotor, the caliper body 12 is pushed back through the guide pin 68 by the reaction force. By this action, the outer pad 62 arranged on the claw portion 18 is pushed out to the rotor side, and the rotor is sandwiched between the inner pad 60 and the outer pad 62 to generate a braking force.

  Next, when the air chamber 50 is operated, the linear motion rod 48 moves in a direction protruding from the air chamber 50, and the cam lever 46 is rotated (swinged) in the direction of arrow B (see FIG. 1). As a result, the rotation shaft 36a rotates and the large diameter portion 36b rotates. When the large-diameter portion 36b rotates, the connecting rod 42 that is in sliding contact with the cam portion 36c is pushed out toward the operating spring 28, and a reaction force that pushes back the guide 30 is generated.

  When the guide 30 is pushed back by the generation of the reaction force, the pressing force applied to the piston 26 connected to the guide 30 by the connecting pin 44 is also released. As a result, the braking of the rotor caused by being sandwiched between the inner pad 60 and the outer pad 62 is released.

  On the other hand, when the operation of the air chamber 50 is released, the reaction force via the connecting rod 42 is released. As a result, the connecting rod 42 and the piston 26 are pushed back together with the guide 30 by the pressing force of the operating spring 28, and a pressing force against the inner pad 60 is generated. At this time, the large diameter portion 36 b is pushed back to the initial position via the connecting rod 42.

  Moreover, in the said embodiment, although the air chamber 50 is mentioned as an example as an actuator, a motor etc. can also be employ | adopted (not shown). When a motor is used as an actuator, a crank lever (not shown) or the like is interposed between the linear motion rod 48 and the motor rotation shaft in order to convert the rotational force into a linear force. You can make it.

10 ......... Disc brake device, 12 ......... Caliper body, 14 ......... Body body, 16 ......... Bridge part, 18 ......... Nail part, 18a ...... Through hole, 20 ...... Cylinder, 22 ......... Bore, 24 ......... Bearing hole, 26 ......... Piston, 26a ......... Through hole, 26b ......... Axial hole, 28 ......... Operating spring, 30 ......... Guide, 30a ......... Projection, 30b ......... Flange, 31 ......... Adjuster, 31a ......... Slider, 32 ......... Plug, 32a ......... Through hole, 34 ......... Fastening plate, 36 ...... Camshaft, 36a ......... Rotating shaft, 36b ......... Large diameter part, 36c ......... Cam part, 38 ......... Shaft holder, 42 ...... Connecting rod, 44 ......... Connecting pin, 46 ...... Cam lever, 48 ... …… Direct acting rod, 50 ……… Air chamber 52 ......... clevis 60 ......... inner pad, 62 ......... outer pad, 64 ......... adjusting bolt, 66 ......... support, 68 ......... guide pin.

Claims (2)

In a disc brake device that presses a brake pad via one end face by a piston disposed in a cylinder formed in a caliper body receiving a pressing force from an operating spring,
When a rotational force is input, a reaction force that releases the pressing force against the piston is generated to push back the piston, and when the rotational force input is released, the pressing force is received to push back to the initial position. A disc brake device, wherein an axis of a camshaft having a cam portion is disposed so as to avoid a range of a back meat portion located on an extension line of a bridge portion in the caliper body.   The shaft center is arranged such that at least a part of the camshaft passes through the center of the cylinder and is parallel to both the arrangement surface of the back portion and the arrangement surface of the brake pad. The disc brake device according to claim 1.

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