WO2013084363A1

WO2013084363A1 - Disk brake vibration estimation method and disk brake vibration estimation device

Info

Publication number: WO2013084363A1
Application number: PCT/JP2011/078607
Authority: WO
Inventors: 龍太郎三住
Original assignee: トヨタ自動車株式会社
Priority date: 2011-12-09
Filing date: 2011-12-09
Publication date: 2013-06-13

Abstract

A disk brake vibration estimation method for estimating vibration at the time of contact between a disk rotor of a disk brake that generates braking force and a pad by bringing the pad into contact with the rotating disk rotor comprises: acquiring input physical quantities that are physical quantities relating to the disk rotor and the pad (step ST1); estimating the vibration of the disk brake on the basis of the acquired input physical quantities, load variations between the disk rotor and the pad and between the pad and a fluid pressure receiving part, a friction variation between the disk rotor and the pad, and in-plane direction vibratory force generated in the circumferential direction of the disk rotor (step ST2); and displaying the result of the estimation (step ST3). The vibration of the disk brake in an in-plane direction can be estimated.

Description

Disc brake vibration estimation method and disc brake vibration estimation device

The present invention relates to a disc brake vibration estimation method and a disc brake vibration estimation device.

The disc brake generates braking torque by bringing the pad into contact with the disc rotor rotating by the hydraulic pressure of the hydraulic cylinder. In the disc brake, vibration occurs when the pad comes into contact with the rotating disc rotor, and so-called brake noise occurs when the rotating disc rotor and the pad resonate. Here, there are an out-of-plane vibration mode and an in-plane vibration mode as vibration modes of brake squeal. The out-of-plane vibration mode is a mode in which the friction surface with which the pad of the disk rotor contacts swings in the same direction as the rotation axis. The in-plane vibration mode is a mode in which the friction surface of the disk rotor vibrates in the circumferential direction of the disk rotor.

A technique for estimating brake squeal corresponding to only the out-of-plane vibration mode has been proposed. Further, a method for estimating the natural frequency of the disk rotor has been proposed by paying attention to the in-plane vibration mode (Patent Document 1).

JP 2004-19715 A

As described above, since the in-plane vibration mode is also one factor constituting the brake noise, it is desired to estimate the disc brake vibration in the in-plane vibration mode. Also, if the disc brake vibration in both out-of-plane vibration mode and in-plane vibration mode can be estimated, a disc brake model can be created and the brake squeal can be estimated by simulation. It is also possible to design a disc brake that suppresses brake noise.

The present invention has been made in view of the above, and an object of the present invention is to provide a disc brake vibration estimation method and a disc brake vibration estimation device capable of estimating the disc brake vibration in the in-plane direction.

In order to solve the above-described problems and achieve the object, the present invention estimates vibrations at the time of contact between the disk rotor and the pad of a disk brake that generates a braking force by bringing the pad into contact with a rotating disk rotor. A disc brake vibration estimation method for obtaining at least an input physical quantity that is a physical quantity related to the disk rotor and the pad, at least the acquired input physical quantity, and an in-plane direction occurrence occurring in a circumferential direction of the disk rotor. And a procedure for estimating the vibration of the disc brake based on the vibration force.

Further, in the disk brake vibration estimation method, the input physical quantity includes a physical quantity related to a hydraulic pressure receiving portion that receives a hydraulic pressure of a hydraulic cylinder that contacts the pad and contacts the pad rotor with the pad. The procedure for estimating the vibration of the brake includes the acquired input physical quantity, load variation between at least the disk rotor and the pad and between the pad and the hydraulic pressure receiving portion, the disk rotor and the pad, Is preferably performed based on the frictional fluctuation between the two and the excitation force generated in the rotation direction of the disk rotor.

Further, the present invention is a disc brake vibration estimation device for estimating a vibration at the time of contact between the disc rotor and the pad of a disc brake that generates a braking force by bringing a pad into contact with the rotating disc rotor, The disk rotor, the input physical quantity acquisition means for acquiring an input physical quantity that is a physical quantity related to the pad, the disk based on at least the acquired input physical quantity and an in-plane excitation force generated in the rotation direction of the disk rotor And vibration estimation means for estimating the vibration of the brake.

The disk brake vibration estimation method and the disk brake vibration estimation apparatus according to the present invention have an effect that the vibration of the disk brake can be estimated at least in the in-plane direction.

FIG. 1 is a diagram illustrating a configuration example of a disc brake vibration estimation apparatus that executes a disc brake vibration estimation method according to the present embodiment. FIG. 2 is a diagram showing a flowchart of the disc brake estimation method according to the present embodiment. FIG. 3 is a diagram illustrating a configuration example of a physical model of a disc brake used for disc brake vibration estimation. FIG. 4 is a diagram showing the results of a physical model that does not consider the in-plane direction excitation force. FIG. 5 is a diagram showing the results of a physical model that considers the in-plane direction excitation force. FIG. 6 is a diagram showing a result of disc brake vibration estimation by the disc brake vibration estimation method according to the present embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the structures described below can be combined as appropriate. Various omissions, substitutions, or changes in the configuration can be made without departing from the scope of the present invention.

Embodiment
The disc brake vibration estimation method according to the present embodiment estimates the disc brake vibration in both the out-of-plane vibration mode and the in-plane vibration mode which are the vibration modes of the brake squeal, that is, the brake squeal using the disc brake vibration estimation device. is there. FIG. 1 is a diagram illustrating a configuration example of a disc brake vibration estimation apparatus that executes a disc brake vibration estimation method according to the present embodiment.

The disc brake vibration estimation device 1 includes a processing unit 3 and a storage unit 2 which are processing means. An input / output device 4 is connected to the disc brake vibration estimation device 1, and an input means 41 provided therein inputs an input physical quantity, commands to the storage unit 2 and the processing unit 3, for example, to the processing unit 3. It gives a command to execute the disc brake vibration estimation method. Here, input devices such as a keyboard, a mouse, and a microphone can be used as the input means 41.

The storage unit 2 stores a disc brake vibration estimation program in which the disc brake vibration estimation method according to the present embodiment for realizing the estimation of the vibration of the disc brake 100 is incorporated. Here, the storage unit 2 is a fixed disk device such as a hard disk device, a flexible disk, a magneto-optical disk device, or a nonvolatile memory such as a flash memory (a storage medium that can only be read such as a CD-ROM), , Storage means such as a volatile memory such as RAM (Random Access Memory), or a combination thereof.

Here, the disc brake vibration estimation program is not necessarily limited to a single configuration, but cooperates with a program already stored in a computer system, for example, a separate program represented by an OS (Operating System). Then, the function may be achieved. Further, a disk brake vibration estimation program for realizing the function of the processing unit 3 shown in FIG. 1 is stored in a computer-readable recording medium, and the disk brake vibration estimation program recorded on the recording medium is read into a computer system. The disc brake vibration estimation method according to the present embodiment may be executed by executing. The “computer system” here includes an OS and hardware such as peripheral devices.

The processing unit 3 includes a memory such as a RAM and a ROM, and a CPU (Central Processing Unit). When estimating the vibration of the disc brake 100, the processing unit 3 stores the disc brake vibration estimation program in the memory (not shown) of the processing unit 3 based on the input physical quantity input to the disc brake vibration estimation device 1 as described above. To perform the operation. Note that the processing unit 3 appropriately stores a numerical value in the middle of the calculation in the storage unit 2 and appropriately takes out the stored numerical value from the storage unit 2 and performs the calculation. The processing unit 3 may be realized by dedicated hardware instead of the disc brake vibration estimation program. The estimation result of the vibration of the disc brake 100 created by the calculation of the processing unit 3 is displayed by the display means 42 of the input / output device 4. Here, LCD (Liquid Crystal Display), CRT (Cathode Ray Tube), etc. can be used for the display means 42. In addition, the vibration estimation result of the disc brake 100 can be output to a printer (not shown). Moreover, the memory | storage part 2 may be provided in the process part 3, and may be provided in another apparatus (for example, database server). Moreover, the structure which can access the disk-brake vibration estimation apparatus 1 by either a wired or wireless method from the terminal device which is provided with the input / output device 4 is not sufficient.

The processing unit 3 includes an input physical quantity acquisition unit 31 and a vibration estimation unit 32. The input physical quantity acquisition unit 31 acquires the input physical quantity input by the input unit 41 or the input physical quantity already stored in the storage unit 2. Here, the input physical quantity is the hydraulic pressure receiving portion 103 (piston or cylinder claw) that receives the hydraulic pressure of the hydraulic cylinder 104 that makes contact with the disk rotor 101, the pad 102, and the pad 102, and makes the pad 102 contact the disk rotor 101. For example, the size, mass, moment of inertia, longitudinal elastic modulus, shear elastic modulus, etc. of each part. The vibration estimation unit 32 acquires the input physical quantity, the in-plane direction vibration force generated in the circumferential direction (rotation direction) of the disk rotor 101, and the disk rotor 101 and the pad 102. The vibration of the disc brake 100 is estimated based on the load variation, the load variation between the pad 102 and the hydraulic pressure receiving portion 103, and the friction variation between the disc rotor 101 and the pad 102. In the present embodiment, the vibration estimation unit 32 estimates the vibration of the disc brake 100 based on the input physical quantity and the following mathematical formula 1. In addition, the following numerical formula 1 is a term of a mass term, a rigidity term, a term of surface pressure variation, a term of frictional force variation, and a term of in-plane direction vibration force in order from the left. Here, the in-plane excitation force is the circumferential direction (rotation of the disk rotor) determined based on the contact rigidity in the in-plane direction between the disk rotor 101 and the pad 102 and the displacement of the disk rotor 101 and the pad 102. Direction).

Next, the disc brake vibration estimation method will be described. FIG. 2 is a diagram showing a flowchart of the disc brake vibration estimation method according to the present embodiment. FIG. 3 is a diagram illustrating a configuration example of a physical model of a disc brake used for disc brake vibration estimation.

First, in the disc brake vibration estimation method according to the present embodiment, as shown in FIG. 2, the input physical quantity acquisition unit 31 of the processing unit 3 acquires the input physical quantity (step ST1).

Next, the vibration estimation unit 32 of the processing unit 3 estimates the vibration of the disc brake 100 based on the input physical quantity acquired by the input physical quantity acquisition unit 31 and the above mathematical formula 1 (step ST2). Here, the above formula 1 corresponds to the physical model of the disc brake 100 shown in FIG. As shown in the figure, the physical model models the disc rotor 101, the pad 102, and the hydraulic pressure receiving portion 103, respectively, and the in-plane direction of the disc rotor 101, the pad 102, and the hydraulic pressure receiving portion 103 (X shown in the same figure). Direction) and out-of-plane direction (Z direction shown in the figure), contact rigidity in the in-plane direction and out-of-plane direction between the disk rotor 101 and the pad 102 (hereinafter simply referred to as “between the rotor and the pad”). The contact stiffness in the out-of-plane direction between the pad 102 and the hydraulic pressure receiving portion 103 (hereinafter simply referred to as “between the pad and the receiving portion”) is used as a coefficient.

Next, how to derive Equation 1 will be described. First, the balance between the force and moment acting on the vibration system is defined by the following formulas 2 to 4 for the disk rotor 101, the following formulas 5 to 7 for the pad 102, and the following formulas 8 to 10 for the hydraulic pressure receiving portion 103. can do. Further, the external force (F, F ′) between the rotor and the pad acting on the vibration system can be defined by the following mathematical expressions 11 and 12. Further, the external force (P, P ′) between the pad and the receiving portion can be defined by the following mathematical formulas 13 and 14.

Here, as shown in FIG. 3, the coefficients in Equations 2 to 14 are as follows: Xr: in-plane displacement of the disk rotor 101 (displacement of the disk rotor 101 in the X direction), Xp: in-plane displacement of the pad 102 (pad 102 Xc: displacement in the X direction), Xc: in-plane displacement of the hydraulic pressure receiving portion 103 (displacement in the X direction of the hydraulic pressure receiving portion 103), Zr: out-of-plane displacement of the disc rotor 101 (displacement in the Z direction of the disc rotor 101) , Zp: out-of-plane displacement of the pad 102 (displacement of the pad 102 in the Z direction), Zc: out-of-plane displacement of the hydraulic pressure receiving portion 103 (displacement in the Z direction of the hydraulic pressure receiving portion 103), θr: deflection of the disc rotor 101 Angle (rotation angle of the disk rotor 101 in the XZ plane), θp: deflection angle of the pad 102 (rotation angle of the pad 102 in the XZ plane), θc: liquid Deflection angle of the receiving portion 103 (rotation angle of the hydraulic pressure receiving portion 103 in the XZ plane), Mr: mass of the disc rotor 101, Mp: mass of the pad 102, Mc: mass of the hydraulic pressure receiving portion 103, Ir: disc rotor 101 Moment of inertia, Ip: moment of inertia of the pad 102, Ic: moment of inertia of the hydraulic pressure receiving portion 103, a: the hydraulic pressure receiving portion 103 with respect to the pad 102 from the surface pressure center reference between the disk rotor 101 and the pad 102. Distance to the contact position, 2b: thickness of the hydraulic pressure receiving portion 103 (width in the Z direction in the hydraulic pressure receiving portion 103), 2c: thickness of the pad 102 (width in the Z direction of the pad 102), 2d: disk rotor 101 (The width of the disk rotor 101 in the Z direction), 2l: the length of the pad 102 (the width of the pad 102 in the X direction), : Static load, F: Fluctuation of surface pressure between rotor and pad (fluctuation of force in Z direction shown in the figure), F ′: Friction force fluctuation generated by fluctuation of surface pressure between rotor and pad, μ: Rotor Friction coefficient between pads, P: variation in surface pressure between pad and receiving portion (force variation in the Z direction shown in the figure), P ′: variation in frictional force caused by variation in surface pressure between pad and receiving portion, μ ': Friction coefficient between pad and receiving part, Krx: rigidity in the in-plane direction of the disk rotor 101, Krz: rigidity in the out-of-plane direction of the disk rotor 101, Krθ: bending rigidity of the disk rotor 101, Kpx: surface of the pad 102 Rigidity in the inward direction, Kpz: Stiffness in the out-of-plane direction of the pad 102, Kpθ: Bending rigidity of the pad 102, Kcx: Rigidity in the in-plane direction of the hydraulic pressure receiving part 103, Kcz: Hydraulic pressure receiving part 10 , Kcθ: contact rigidity in the out-of-plane direction between the rotor and pad, K′pr: contact rigidity in the in-plane direction between the rotor and pad, Kcp: Contact stiffness between the pad and the receiving portion in the out-of-plane direction, Kt: Contact stiffness in the in-plane direction of the mounting 105 that holds the pad 102. Here, the rigidity is the rigidity of each part itself, the bending rigidity is the bending rigidity of each part itself, the contact rigidity is the rigidity (shear rigidity) at the contact surface between the parts, and the longitudinal elastic modulus of each part. It is obtained from the shear modulus.

Next, the above formulas 11 to 14 are substituted into the formulas 2 to 10, and F, F ', P, and P' are converted to obtain the following formulas 15 to 23.

When the above formulas 15 to 23 are expressed in a matrix, as in the above formula 1, the mass term and the stiffness term, the surface pressure fluctuation term, the friction force fluctuation term, and the circumferential direction (rotation direction) of the disk rotor 101 are generated. This is a balance formula with the term of spring force, that is, in-plane direction vibration force. Here, [M], [U], [K], [Kcpr], [μKcpr], and [K′cpr] are expressed by the following equations 24 to 29, respectively.

It was confirmed that the above formula 1 is unstable in the in-plane vibration mode, that is, whether the vibration of the disc brake 100 in the in-plane vibration mode can be estimated. FIG. 4 is a diagram showing the results of a physical model that does not consider the in-plane direction excitation force. FIG. 5 is a diagram showing the results of a physical model that considers the in-plane direction excitation force. 4 and 5, the vertical axis represents frequency and the horizontal axis represents the friction coefficient. FIG. 4 shows the results of numerical analysis with K′cpr = 0. FIG. 5 shows the result of numerical analysis with K′cpr = 0.2 × Kcpr. 4 and 5, the line is the boundary between the stable region and the unstable region, and the hatched portion is the unstable region. As shown in FIG. 4, as a result of numerical analysis based on a physical model that does not consider the in-plane direction excitation force, stable in the in-plane vibration mode, that is, no vibration of the disc brake 100 occurs in the in-plane direction (surface Inward brake squeal does not occur). On the other hand, as shown in FIG. 5, as a result of numerical analysis based on a physical model that takes into account the in-plane direction excitation force, the in-plane vibration mode is unstable, that is, the disc brake 100 vibrates in the in-plane direction. There was a region where the brake squeal occurred in the in-plane direction.

Next, the processing unit 3 displays the estimation result on the display means 42 (step ST3). Here, the processing unit 3 displays a screen on the display unit 42 so that the operator can recognize the vibration of the disc brake 100 in the in-plane direction estimated by the vibration estimation unit 32. FIG. 6 is a diagram showing a result of disc brake vibration estimation by the disc brake vibration estimation method according to the present embodiment. For example, as shown in FIG. 6, the processing unit 3 has a peak of the vibration (frequency [KHz]) of the disc brake 100 in the out-of-plane direction, and the vibration of the disc brake 100 in the in-plane direction as shown in FIG. Display the peak. Note that the screen displayed on the display means 42 is not limited to the above-described FIG. 6, and only the vibration of the disc brake 100 in the in-plane direction may be displayed and corresponds to the vibration of the disc brake 100 in the in-plane direction. The frequency value and peak size may be displayed numerically.

As described above, according to the disc brake vibration estimation method according to the present embodiment, the in-plane direction and the out-of-plane direction are based on the input physical quantity, the load variation, the friction variation, and the in-plane direction excitation force. Therefore, it is possible to estimate the vibration of the disc brake 100 in a short time compared with the conventional method of estimating the vibration of the disc brake 100 in the in-plane direction by an experiment using an actual disc brake device. The vibration of the disc brake 100 in the in-plane direction can be easily estimated. Therefore, for example, when a simulation using FEM (Finite Element Method) is performed to predict the performance of the disc brake 100, a disc brake model that approximates the actual disc brake 100 (see FIG. 3). The disc brake vibration estimation method according to the present embodiment is used when predicting the vibration of the disc brake 100 when an external force is applied to the disc brake model and the pad model is brought into contact with the disc brake model. it can.

It should be noted that the disc brake vibration estimation method according to the present embodiment can also be used for the design method of the disc brake 100. In the design method of the disc brake 100, each component of the disc brake 100, that is, the disc rotor 101, the pad 102, the hydraulic pressure, is controlled so as to suppress the vibration of the disc brake 100 in the in-plane direction estimated by the disc brake vibration estimation method. The receiving part 103 will be designed. Since the vibration of the disc brake 100 in the in-plane direction, that is, the brake squeal in the in-plane direction, is likely to occur when the in-plane direction excitation force is increased, the term of the in-plane direction excitation force in the above-described Equation 1 is It is preferable to design each part of the disc brake 100 so as to be small. Specifically, in order to reduce the contact stiffness [K′cpr] in the in-plane direction between the rotor and the pad, for example, the pad 102 is designed so that the shear stiffness of the contact surface of the pad 102 with respect to the disk rotor 101 is reduced. The disk rotor 101 is designed so that the shear rigidity of the contact surface with the pad 102 of the disk rotor 101 is reduced. Alternatively, in order to reduce the displacement [U], for example, the hydraulic pressure receiving of the pad 102 is performed for the purpose of reducing the displacement Zp in the Z direction due to the bending of the pad 102 (decreasing the bending displacement of the pad 102). The pad 102 is designed for the purpose of reducing the bending angle θp of the pad 102 (decreasing the bending displacement of the pad 102), or designing the pad 102 so as to increase the sectional moment of inertia of the base material (not shown) that contacts the portion 103. The pad 102 is designed so as to reduce the bending force, and the disc rotor 101 is designed so that the in-plane displacement Xr of the disc rotor 101 becomes small. When designing the disc brake 100 using a disc brake automatic design device that automatically designs the disc brake 100, the constraint condition is that the term of the in-plane direction excitation force in the above Equation 1 is a predetermined value or less. The disc brake 100 is automatically designed.

DESCRIPTION OF SYMBOLS 1 Disc brake vibration estimation apparatus 2 Memory | storage part 3 Processing part 31 Input physical-quantity acquisition part 32 Vibration estimation part 4 Input / output device

Claims

A disc brake vibration estimation method for estimating a vibration at the time of contact between the disc rotor and the pad of a disc brake that generates a braking force by bringing a pad into contact with a rotating disc rotor,
A procedure for obtaining an input physical quantity that is a physical quantity related to at least the disk rotor and the pad;
A procedure for estimating vibration of the disc brake based on at least the acquired input physical quantity and an in-plane direction vibration force generated in a circumferential direction of the disc rotor;
Including a disc brake vibration estimation method.
The input physical quantity includes a physical quantity related to a hydraulic pressure receiving portion that receives a hydraulic pressure of a hydraulic cylinder that contacts the pad and contacts the pad to the disk rotor;
The procedure for estimating the vibration of the disc brake includes the acquired input physical quantity, a load variation between at least the disc rotor and the pad and between the pad and the hydraulic pressure receiving portion, the disc rotor, and the The disc brake vibration estimation method according to claim 1, wherein the disc brake vibration estimation method is performed based on a frictional fluctuation with a pad and a vibration force generated in a rotation direction of the disc rotor.
A disk brake vibration estimation device that estimates vibrations at the time of contact between the disk rotor and the pad of a disk brake that generates a braking force by bringing a pad into contact with a rotating disk rotor,
Input physical quantity acquisition means for acquiring an input physical quantity that is a physical quantity related to at least the disk rotor and the pad;
Vibration estimation means for estimating vibration of the disk brake based on at least the acquired input physical quantity and an in-plane direction vibration force generated in the rotation direction of the disk rotor;
A disc brake vibration estimation device comprising: