JP2002340069A - Lifetime display device of brake element for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a driver to know certainly the replacing timing of a brake element such as a pad whether before or after the replacement without giving a feel of unease to the driver by displaying the lifetime of the brake element. SOLUTION: A sensor circuit 11 senses that the lining of the brake element has worn in a specified amount, and a distance measuring means 12 measures the running distance of a vehicle. A calculator 13 determines the lifetime till attainment of the allowable limit thickness for wear on the basis of the residual thickness when the lining has worn in the specified amount and the running distance till attainment of the specified amount, while a display 14 displays the lifetime. At the time of replacing the brake element, either of a reset switch 19 and a wear ratio keeping switch 20 is operated so that it is possible to display the lifetime of the new brake element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a device for indicating the life of a brake element for a vehicle, which is used as a brake shoe assembly for a drum brake or a pad for a disc brake for a brake element used for braking a vehicle such as an automobile. This is for notifying the driver of the life, in other words, the distance that can be traveled before the replacement. In this specification, the term "brake element" refers to a general term for a brake shoe assembly and a pad. Conversely, in this specification, a brake shoe assembly refers to a brake element for a drum brake, and a pad refers to a brake element for a disc brake.

[0002]

2. Description of the Related Art A brake for a vehicle incorporates a brake element having a lining attached to a back plate. When braking is performed, the lining is pressed against a rotating rotating body such as a drum or a disk. This lining is
Since the wear gradually occurs due to repeated braking, when the wear has progressed to a certain extent, it must be replaced with a new brake element. However, since it is impossible or difficult to visually determine the thickness of the lining from the outside, a sensor called a wear indicator is attached to the brake element, and when the lining is worn to an allowable limit, Based on a signal from the wear indicator, an alarm device provided in the driver's seat issues a command to prompt replacement of the brake element.

FIG. 4 shows an example of a pad with a wear indicator described in Japanese Utility Model Laid-Open No. 5-47562, which has been considered to achieve such an object. At the end of the back plate 2 constituting the pad 1 and protruding from the periphery of the lining 3, a mounting hole 4 is formed in a state penetrating the front and back surfaces of the back plate 2, and inside the mounting hole 4. The wear indicator 5 is mounted via a holding cylinder 6 and a compression spring 7. The wear indicator 5 is formed by burying a conductor 9 as a detection unit in a holder 8 made of synthetic resin. With such a wear indicator 5 supported on the back plate 2, the distal end of the conductive wire 9 is positioned on the wear allowable limit surface X of the lining 3.

When the lining 3 is worn due to the repetition of braking and its thickness is reduced, first, the tip of the holder 8 is worn by friction with the disk 10.
When the wear further proceeds, the tip of the conductor 9 buried in the holder 8 and the side surface of the disk 10 rub against each other, and the conductor 9 is broken at the tip. The breaking of the conductive wire 9 is detected by a detection circuit (not shown), which sends a signal to an alarm device provided in the driver's seat, and issues a command to prompt the replacement of the pad 1 by the alarm device.

[0005] Conventionally known pad wear alarms simply alert suddenly without notice that the pad lining is running low. For this reason, there is a possibility that a general driver may be anxious. On the other hand, for example, Japanese Patent No. 2689272 discloses that
A device is disclosed which notifies the driver of the degree of lining wear in a plurality of stages. However, even with this improved device, it is not possible to inform the driver of the life of the lining at an intermediate stage, that is, the distance that can be traveled before braking becomes impossible. The same applies to a case where the brake element is a brake shoe assembly for a drum brake.

[0006]

[Description of the Prior Invention] In view of such circumstances, the inventor of the present invention does not give a general driver who has no knowledge of the brake device without giving anxiety, and also makes sure that the replacement timing of the brake element is ensured. (Japanese Patent Application No. 2001-105984). First, a life indicator for a vehicle brake element according to the invention will be described.

FIGS. 5 to 8 show a first example of the above-mentioned embodiment of the invention. First, FIG. 5 is a block diagram showing a control unit of the life display device for a vehicle brake element according to the present invention. The control unit includes a detection circuit 11 and a distance measurement unit 12.
, A computing unit 13 and a display unit 14. The detection circuit 11 is for detecting that the wear amount of the lining 3 constituting the pad 1 as shown in FIGS. 6 and 7 has reached a predetermined value. For this purpose, a conductor 15 is provided on the pad 1 so that the conductor 15 is cut off in the course of wear of the lining 3. The installation structure of the conductor 15 on the pad 1 is not particularly limited. The structure shown in FIG. 4 described above can also be adopted. Alternatively, a printed resistor called a trimming resistor can be used. When such a trimming resistor is used, the lining 3 is used.
Is a conductive film, a trimming resistor printed on an insulating film is applied to the lining 3
It is conceivable that it is attached to the peripheral surface of.

In any case, the distal end of the conductor 15 is arranged at a predetermined position in the middle of the lining 3 in the thickness direction as shown in FIG. 6, and as shown in FIG. However, when the disk 10 is worn by a predetermined amount T ₀ , the disk 10 is cut by friction with the side surface of the disk 10. When the conductor 15 is cut, the voltage applied to the detection circuit 11 changes, so that the detection circuit 11 cuts the conductor 15, that is, the lining 3 moves to the predetermined amount T _0. Detects wear by minutes. Then, the detection circuit 11 sends a disconnection signal indicating that the conductor 15 has been disconnected to the computing unit 13. On the other hand, the distance measuring means 12 measures the traveling distance of the vehicle. Such a distance measuring means 12 does not need to be specially prepared in order to constitute the device for indicating the life of the brake element of the vehicle of the invention, and the odometer of the vehicle can be used as it is.
In any case, the distance measuring means 12 sends out a distance signal indicating the traveling distance of the vehicle to the computing unit 13.

The arithmetic unit 13 is provided with the detection circuit 11
Represents the ratio of the amount of wear of the lining 3 to the running distance based on the disconnection signal sent from the distance measuring device and the distance signal sent from the distance measuring means 12 and indicating the running distance until the conductor 15 is cut. Find the wear ratio. Further, the life of the pad 1 is calculated based on the wear ratio and the remaining amount of the lining 3 at the time when the conductor 15 is disconnected (the remaining thickness T _X up to the allowable wear limit surface _X ). . This point will be described with reference to FIG.

[0010] O in FIG._s To pad 1 which was exchanged for a new one
Assume that the conductor 15 incorporated is cut at the point α in FIG.
I do. In this case, after replacing the pad 1,
The traveling distance until the body 15 is cut is L₀ And or,
The amount of wear of the lining 3 is determined by the predetermined amount T₀ It is.
Therefore, the conductor 15 is disconnected after the pad 1 is replaced.
Until cut off, the lining 3
The wear ratio representing the rate of wear, that is, the solid line O in FIG._s −α
The slope of T₀ / L₀ Becomes The lining 3 is
Assuming that wear continues at the same rate after
Line O_s -The chain line that extends α as it is, and the thickness of the lining
The position on the vertical axis indicates the wear of the lining 3
The point O where the horizontal axis is the position of the allowable limit plane X_e 
The pad 1 reaches the end of its life.
It is expected). Therefore, the point O_e At
Mileage L_e And the traveling distance until the conductor 15 is cut.
Release L ₀ Difference "L_e -L₀ When the conductor 15 is cut.
The life of the pad 1 at the point of time (the point α)
calculate. And if the car is running from this point
For example, the traveling distance L from this point_x The conductor 15
The value "L" subtracted (subtracted) from the life at the time of_e −
L₀ -L_x Is calculated as the life of the pad 1 at that time.
Put out.

The display 14 displays the life of the pad 1 calculated by the calculator 13 as described above. As such a display 14, the same as various display devices conventionally provided on the dashboard portion of the vehicle can be adopted. In other words, on this dashboard part, for example, characters such as "pad has worn down to 2/3", "you can run Xkm after pad replacement" are displayed, or analog type indicating the degree of wear with a needle is displayed. Display means such as a meter can be employed.

If necessary, it is estimated that the lining 3 has been worn down to a wearable limit thickness (the point _Oe).
When the travel distance _Le has been reached), a warning to prompt the replacement of the pad 1 can be issued by voice or buzzer. Further, in the case where the operation of the vehicle is continued without replacing the pad 1 even when the thickness exceeds the allowable wear thickness (thinner), the power supply to the starter for starting the engine may be stopped. It is also possible to perform control so that a particularly loud warning sound is emitted at the time of starting (and, if necessary, traveling).

Next, FIGS. 9 to 20 show a second example of the embodiment of the present invention. In the case of this example, a plurality of (three in the illustrated example) conductors 15a, 15b, and 15c are installed at different positions in the thickness direction of the lining 3 that forms the pad 1. That is, the first-stage conductor 15 is based on the friction surface 16 of the lining 3 of the new pad 1.
a is disposed at a portion closer to the back plate 2 by a thickness T ₁ from the friction surface 16. Further, the second stage of the conductor 15b, are installed further the _second thickness T ₂ minutes only the portion closer to the back plate 2 side of the conductor 15a of the first stage above. Further, the third-stage conductor 15c has a further thickness T than the second-stage conductor 15b.
It is installed on the part close to the back plate 2 for ₃ minutes. The thicknesses T ₁ , T ₂ and T ₃ are equal to each other (T ₁
= T ₂ = T ₃ ), but if the respective values are known, they need not necessarily be equal. In addition, the third-stage conductor 15c is connected to the back plate 2 for T ₄ minutes from the allowable wear surface.
It is installed on the side away from

In any case, when the lining 3 gradually wears due to repetition of braking, the conductors 15
a, 15b, and 15c are sequentially cut in accordance with the amount of wear of the lining 3. In the case of the present example, by sequentially cutting the plurality of conductors 15a, 15b, and 15c in this manner, the wear amount of the lining 3 is detected by the detection circuit 11a in a plurality of stages. Then, a disconnection signal indicating that one of the conductors 15a (or 15b, 15c) has been cut is sent out to the computing unit 13 (see FIG. 5). The arithmetic unit 13 calculates the disconnection signal sent from the detection circuit 11a and the wear amount and travel distance between the time when a new conductor is cut and the time immediately before another conductor is cut. Based on this, a wear ratio representing the ratio of the wear amount of the lining 3 to the travel distance is obtained. Then, the life of the pad 1 is calculated based on the wear ratio and the remaining amount of the lining 3 at the time when the conductor is newly cut. However, after the new pad 1 is mounted and before the first-stage conductor 15a is cut, the wear ratio between the wear amount of the lining 3 and the travel distance set in advance and the distance measurement means 12 (FIG. 5) ) Is calculated based on the signal indicating the traveling distance sent from the pad 1). These points will be described with reference to FIGS.

First, as shown in FIG. 10, when the use of the pad 1 is started from a state where a new pad 1 (the lining 3 is not worn) is mounted, the wear amount of the lining 3 set in advance is determined. The life of the pad 1 is calculated based on a standard wear ratio, which is a ratio to the traveling distance, and a signal representing the traveling distance sent from the distance measuring means 12. That is, in this case, the lining 3 is determined based on the standard wear ratio obtained in consideration of the standard use condition.
Estimate the amount of abrasion. FIG. 11 shows the relationship between the running distance and the amount of wear of the lining 3 set based on the standard wear ratio, and FIG. 12 shows the life of the pad 1 obtained based on the relationship shown in FIG. The operation at that time is shown respectively. By displaying the life of the pad 1 using such a standard wear ratio, the life of the pad 1 can be displayed immediately after the new pad 1 is mounted. For this reason, the driver can recognize the presence of the pad 1 which needs to be replaced from an early stage.

With the repetition of braking, the pad 1
When the inning 3 is worn, as shown in FIG.
The step conductor 15a is cut. Replaced pad 1 above
Later, the traveling distance until the first-stage conductor 15a is cut
To L as shown in FIG.₁ And after the exchange,
Amount of wear T until conductor 15a is cut₁ And this
If the above-mentioned first stage conductor 15a is cut under the conditions
If the travel distance L is₁ And wear amount T₁ And based on the above
The wear ratio between the amount of wear of the lining 3 and the running distance, T ₁ / L
₁ Ask for. Then, the lining 3 is
The first stage conductor 1
The thickness of the lining 3 at the time when 5a is cut is
Distance L that can be traveled before it is worn to the allowable thickness_1X
Ask for. After the first-stage conductor 15a is cut
As shown in FIG. 15, the second-stage conductor 15b is cut off.
Until the distance traveled after cutting L_1X″
Distance L that can be traveled when body 15a is cut_1XReduced from
The reduced value L_1X'On the display 14 (see FIG. 5).
View more.

When the lining 3 is further worn and the second-stage conductor 15b is cut off as shown in FIG. 16, after the first-stage conductor 15a is cut off as shown in FIG. The travel distance L ₂ is determined based on the wear amount T ₂ and the travel distance L ₂ until the second-stage conductor 15 b is cut.
Determining the wear ratio T ₂ / L ₂ which is a ratio of the wear amount T ₂ of the said lining 3 for _2. And the above lining 3
However, assuming that the lining 3 will continue to be worn at the same rate thereafter, a travelable distance is calculated until the thickness of the lining 3 is worn to the allowable thickness. Therefore, while the same pad 1 is being used, the owner of the vehicle changes or the running conditions change (change between running in a suburb and running in an urban area), and the like. Even if a situation where the relationship with the mileage greatly differs, correct this,
The travelable distance can be correctly obtained.

After the second-stage conductor 15b is cut, the traveling distance of the second-stage conductor 15b after cutting is measured until the third-stage conductor 15c is cut. The distance that can be traveled when the conductor 15b is cut is subtracted from the travelable distance, and the reduced value is displayed on the display as a travelable distance before pad replacement. The operation in this case is the same as after the first-stage conductor 15a is cut.

The lining 3 is further worn, and FIG.
As shown, when the third-stage conductor 15c is cut,
Shows that the second-stage conductor 15b shown in FIG.
From when the third conductor 15c is cut.
Wear T_Three And mileage L_Three Based on this travel distance L
_Three Wear T of the lining 3_Three Wear ratio T which is the ratio of
_Three / L_Three Ask for. And the lining 3 is
Assuming that it will continue to wear at the same rate
Until the thickness of the ring 3 wears to the wear allowable thickness, that is,
This lining 3 corresponds to T in FIG._Four Can run while wearing
Distance L_Four (L_3X). Basic action in this case
After the first-stage conductor 15a is cut,
The operation is the same as that before the step conductor 15b is cut.
You.

However, in the case of the present embodiment, since the third-stage conductor 15c is the last-stage conductor, the third-stage conductor 15c
After cutting c, as shown in the flowchart of FIG. 20, an operation of determining whether or not the thickness of the lining 3 has reached the allowable wear limit is performed. When the thickness reaches the allowable wear limit, a warning is issued to prompt the driver to replace the pad 1 immediately instead of extinguishing the display of the mileage that can be traveled (0 km in this case). Emit.

In order to correct the change in the amount of wear of the lining 3 due to the temperature change, as shown in FIG. 21, a portion of the end of the back plate 2 constituting the pad 1 protrudes from the peripheral edge of the lining 3. Further, it was considered earlier that a temperature sensor 17 such as a thermistor was provided. In this case, the temperature of the braking portion such as the side surface of the disk 10 is detected by the temperature sensor 17, and the higher the temperature detected by the temperature sensor 17 is, the more the computing unit 13
(See FIG. 5), a correction for shortening the life of the pad 1 is added. As the temperature of the lining 3 increases, the wear increases. The correction based on the measured value of the temperature sensor 17 allows the life of the pad 1 to be calculated more accurately.

Further, a brake sensor for measuring the number of times the brake pedal is depressed is provided, and the longer the number of times the brake pedal is depressed, the shorter the life of the brake element such as the pad 1 in the computing unit 13 is. It is possible to add a correction to be calculated. As described above, the amount of wear of the lining 3 greatly changes depending on the running pattern. Therefore, even in the case of a difference between traveling in a suburb (or a highway) and traveling in an urban area, the wear ratio between the wear amount and the traveling distance depends on the number of times the brake pedal is depressed. T / L
Is corrected, the life of the brake element such as the pad 1 can be calculated more accurately. 9 to 20.
In order to implement the second example of the embodiment of the prior invention as shown in FIG. 22, for example, a wear indicator 5a as shown in FIG.
Is attached to the back plate 2 of the pad 1 and the holding cylinder 6
Attach via a.

[0023]

SUMMARY OF THE INVENTION The vehicle brake device life display device according to the prior invention, which is constructed and operates as described above, ensures the time to replace the brake device without giving the driver an uneasy feeling. Although it can be notified, no special consideration is given to the control after replacing the brake element. On the other hand, when the brake element whose lining has become thin due to wear is replaced with a new brake element having a sufficient thickness, control corresponding to the new brake element must be performed. No. SUMMARY OF THE INVENTION In view of such circumstances, the present invention has been made to realize a vehicle brake element life display device in which a controller can display a new life in response to replacement of a brake element.

[0024]

All of the above-mentioned devices for indicating the life of a brake element for a vehicle according to the present invention detect a conductor that is cut in the process of abrasion of the lining of the brake element and detect that the conductor is cut. A detection circuit that sends out a disconnection signal, a distance measuring unit that sends out a distance signal by measuring the traveling distance of the vehicle, and a wear ratio that represents a ratio of the amount of wear of the lining to the traveling distance based on the disconnection signal and the distance signal. And a calculator for calculating the life of the brake element based on the wear ratio and the remaining amount of the lining when the conductor is disconnected, and an indicator for displaying the life calculated by the calculator. Prepare.

According to a first aspect of the present invention, in addition to the above-described structure, the running distance, the wear ratio, and the disconnection signal stored in a storage unit in the arithmetic unit are provided. And a reset switch for erasing all data indicating that the data has been sent. According to a third aspect of the present invention, in addition to the above-described structure, the vehicle brake element life display device detects that the brake element has been replaced based on a change in a signal sent from the detection circuit to the arithmetic unit. And an exchange detecting means for performing the operation. When the replacement detecting means detects that the brake element has been replaced, the computing unit calculates the traveling distance, the wear ratio, and the disconnection signal stored in the storage unit in the computing unit. It has a function to delete all data indicating that it has been sent.

[0026]

According to the vehicle brake element life display device of the present invention configured as described above, similarly to the above-described vehicle brake element life display apparatus of the preceding invention, the replacement time of the brake element is set to the life. Instead of suddenly notifying just before reaching, it can be notified continuously in advance. For this reason, a general driver does not have to worry. Further, in the case of the device for displaying the life of a vehicle brake element according to the present invention, a new life display can be performed by the controller in response to replacement of the brake element.

First, in the case of the device for indicating the life of a brake element for a vehicle according to the first aspect, by operating a reset switch, the running distance, the wear ratio, and the disconnection stored in the storage unit in the arithmetic unit are operated. Since all data indicating that a signal has been sent can be deleted, a new life display can be performed on the controller in response to the above-mentioned replacement of the brake element. Further, in the case of the device for displaying the life of a brake element for a vehicle according to claim 3, when the replacement detecting means detects that the brake element has been replaced, the information is stored in a storage unit in the arithmetic unit. Since all data indicating the running distance, the wear ratio, and the fact that the disconnection signal has been sent are erased, a new life display can be performed on the controller in response to the replacement of the brake element.

[0028]

1 and 2 show a first example of an embodiment of the present invention corresponding to claims 1 and 2. FIG. still,
A feature of the present invention is to improve the vehicle brake element life display device according to the prior invention described with reference to FIGS.
The point is that the controller can display a new life in response to the replacement of the brake element. Since the configuration and operation of the other parts are the same as those of the above-mentioned invention, overlapping illustration and description are omitted, and the following is a feature of the invention.
The following description focuses on the improvements over the above-mentioned prior invention.

First, the block diagram of FIG. 1 will be described. The arithmetic unit 13 includes a disconnection signal from the detection circuit 11 for detecting that the conductor has been cut, a distance signal from the distance measuring means 12 for measuring the traveling distance of the vehicle, and a A signal from the brake sensor 18 representing the number of times the brake pedal is depressed is input. The detection circuit 11 also has a function as a temperature sensor so that the temperature of a portion related to the temperature of the friction surface of the lining during braking can be detected. In order to provide such a function, a resistor that changes the resistance value according to a temperature change, such as a thermistor, is used for the resistor constituting the detection circuit 11, so that an independent temperature sensor is prepared. You can do without it. Each of the constituent elements 11, 12, and 18 described above
The operation of the computing unit 13 for calculating the remaining life of the brake element on the basis of the signal from the controller and displaying it on the display 14 is the same as in the case of the above-mentioned invention.

Further, in the case of the present invention, the operation unit 13
In addition, a reset signal based on the operation of the reset switch 19, a wear ratio holding signal based on the operation of the wear ratio holding switch 20, and a start signal based on the operation of the ignition switch 21 can be sent. The reset signal is sent to the arithmetic unit 13 based on the operation of the reset switch 19, and the arithmetic unit 13 is stored in the storage unit in the arithmetic unit 13 when the reset signal is sent. All data indicating the running distance, the wear ratio, and the fact that the disconnection signal has been sent are deleted. On the other hand, the wear ratio holding signal is sent to the calculator 13 based on the operation of the wear ratio holding switch 20,
Based on the wear ratio holding signal, the arithmetic unit 13 is provided, on the condition that the reset switch 19 is not operated, of the travel distance, the wear ratio, and data indicating that the disconnection signal is sent. Except for the data representing the wear ratio,
Data indicating the mileage and the fact that the disconnection signal has been sent are erased.

According to the vehicle brake element life display device of the present invention configured as described above, the replacement time of the brake element is determined based on the same operation as the above-described vehicle brake element life display device of the preceding invention. In addition to continuously notifying in advance, it is possible to cause the controller to display a new service life in response to replacement of the brake element. In particular, in the case of the vehicle brake element life display device of this embodiment, by operating the reset switch 19, the travel distance, the wear ratio, and the disconnection signal stored in the storage unit in the arithmetic unit 13 are obtained. Since all the data indicating that the signal has been sent, or the data indicating that the mileage and the disconnection signal have been sent can be deleted by operating the wear ratio holding switch 20, it is necessary to replace the brake element. Correspondingly, a new life display can be displayed on the controller.

When the worn brake element is replaced with a new brake element, one of the reset switch 19 and the wear ratio holding switch 20 is operated. In this case, for example, when the vehicle purchased by the trader is to be maintained before selling it as a used car,
The reset switch 19 is pressed. That is, in this case, since the driver changes before and after the replacement of the brake element, there is no point in using the wear ratio up to that time for subsequent wear amount estimation. So, in this case, like the new car,
All the data is deleted, and the estimation of the wear amount by new data accumulation is started. On the other hand, when the driver becomes the same before and after the replacement of the brake element, such as during a periodic inspection, the wear ratio holding switch 20 is pressed. Then, the wear ratio up to that time is used to estimate the wear amount of the new brake element.

The above operation will be described with reference to FIG. When the start signal based on the operation of the ignition switch 21 is sent to the arithmetic unit 13 after the replacement of the brake element, first, the reset switch 19
It is determined whether is operated (ON). And
When the reset switch 19 is operated,
All data indicating the running distance, the wear ratio, and the fact that the disconnection signal has been sent stored in the storage unit in the arithmetic unit 13 are deleted. The computing unit 13 is connected to the display unit 14
As described with reference to FIGS. 10 to 12, the pad life is displayed based on the standard wear ratio until the first-stage conductor is cut. After the first-stage conductor is cut, the life of the pad is displayed based on the life ratio calculated according to the actual running, as described with reference to FIGS.

On the other hand, the reset switch 19
If is not operated, it is determined whether or not the wear ratio holding switch 20 is operated (ON). When the wear ratio holding switch 20 is operated, the travel distance and the disconnection signal are sent while the wear ratio is left out of the data stored in the storage unit in the arithmetic unit 13. Delete the data representing. Then, the computing unit 13 calculates the remaining thickness of the pad based on the subsequent traveling distance and the remaining wear ratio, and displays the life. After the first-stage conductor is cut, the life of the pad is displayed based on the life ratio calculated according to the actual running, as described with reference to FIGS.

When neither the reset switch 19 nor the wear ratio holding switch 20 is operated,
Since the operation necessary for replacing the brake element is not performed, the remaining life of the pad is not displayed on the display unit 14 until one of the switches is operated. Instead, the computing unit 13 displays on the display 14 that the necessary operation has not been performed. Note that, when the reset switch 19 is operated, a reset signal sent to the arithmetic unit 13 causes
It is also possible to configure so that only the data of the wear ratio is deleted. In this case, the reset switch 19 is operated together with the wear ratio holding switch 20 in the case of maintenance prior to the sale of a used car, and only the wear ratio holding switch 20 is operated in the case of maintenance during a periodic inspection. I do.

Next, FIG. 3 corresponds to claims 3 and 4.
9 shows a second example of the embodiment of the present invention. In the case of this example, an exchange detecting means (not shown) is incorporated in the arithmetic unit 13 (see FIG. 1). And this exchange detection means,
It has a function of detecting that the brake element has been replaced, based on a change in a signal sent from the detection circuit 11 (see FIG. 1) to the arithmetic unit 13. That is, when the brake element from which all the conductors of the detection circuit 11 are cut off is replaced with a new brake element due to the wear of the lining, the resistance value of the wear indicator 5a (see FIG. 22) constituting the detection circuit 11 becomes lower. From ∞ to the initial finite (smallest) value. The replacement detecting means incorporated in the computing unit 13 detects that the brake element has been replaced based on the change in the resistance value.

In the case of this embodiment, when the exchange detecting means detects that the brake element has been exchanged on condition that the wear ratio holding switch 20 (see FIG. 1) is not operated (is OFF). Then, all data indicating the running distance, the wear ratio, and the fact that the disconnection signal has been sent stored in the storage unit in the arithmetic unit 13 are deleted. That is, in the case of the present example, the above-mentioned replacement detecting means performs the same function as the above-described reset switch 19 (see FIG. 1) of the first example. However, in the case of this example, if the wear ratio is to be retained even after the replacement of the brake element, the wear ratio holding switch 20 is operated when replacing the brake element.

The operation of this embodiment will be described below with reference to FIG. First, it is checked whether the (old) brake element used so far has been cut to the last conductor. If the cutting has been completed up to the last stage, the operation proceeds to the replacing operation. On the other hand, when the conductor at the last stage is still conducting, it is not always necessary to proceed to the replacement operation. However, if the brake element whose lining has been worn halfway is removed, the resistance value becomes the same as that when the conductor at the final stage is cut. Therefore, this example does not prevent the replacement of the brake element whose lining has been worn partway.

Whether the brake element whose lining has been worn to its limit or is to be replaced halfway is replaced, the computing unit 13 detects the detection circuit 1
After the resistance value of 1 becomes ∞, a new brake element is incorporated, and when it is detected that the resistance value of the wear indicator 5a portion of this brake element has changed to an initial finite value, the computing unit 13 It is determined whether the wear ratio holding switch 20 is operated. When the wear ratio holding switch 20 is not operated, the travel stored in the storage unit in the arithmetic unit 13 is performed in the same manner as when the reset switch 19 is operated in the first example described above. All data indicating the distance, the wear ratio, and the fact that the disconnection signal has been sent are deleted. Thereafter, the life of the pad is displayed in the same manner as when the reset switch 19 is operated in the first example.

On the other hand, the wear ratio holding switch 2
0 is operated in the same manner as when the wear ratio holding switch 20 is operated in the first example.
Among the data stored in the storage unit 3, the data representing the running distance and the fact that the disconnection signal has been sent are deleted, leaving the wear ratio. Then, the computing unit 13 calculates the remaining thickness of the pad based on the subsequent traveling distance and the remaining wear ratio, and displays the life. Hereinafter, the first
In the example, the life of the pad is displayed in the same manner as when the wear ratio holding switch 20 is operated.

[0041]

Since the device for indicating the life of a brake element of a vehicle according to the present invention is constructed and operates as described above, it is possible to replace the brake element without giving the driver an uneasy feeling as in the case of the prior invention. It is possible to notify the time reliably, which can contribute to the safe operation of vehicles such as automobiles. Further, in the case of the present invention, an appropriate life display can be made even after the replacement of the brake element.

[Brief description of the drawings]

FIG. 1 is a block diagram of a first example of an embodiment of the present invention.

FIG. 2 is also a flowchart.

FIG. 3 is a flowchart of a second example of the embodiment of the present invention.

FIG. 4 is a partial cross-sectional view showing one example of a conventionally known pad with a wear indicator.

FIG. 5 is a block diagram showing a control unit of the life display device for a vehicle brake element of the prior invention.

FIG. 6 shows a state in which lining wear has not progressed;
The schematic diagram of the wear detection part which comprises the 1st example of embodiment of prior invention.

FIG. 7 is a schematic diagram of a wear detecting unit also showing a state in which wear has advanced.

FIG. 8 is a diagram for explaining pad life calculation based on a relationship between a wear amount and a traveling distance.

FIG. 9 is a schematic diagram of a wear detecting section constituting a second example of the embodiment of the prior invention.

FIG. 10 is a schematic view of a wear detecting portion constituting a second example of the embodiment of the present invention, showing a state in which lining wear has not progressed.

FIG. 11 is a diagram for explaining pad life calculation performed before a first-stage conductor is cut.

FIG. 12 is a flowchart of pad life calculation performed before the first-stage conductor is cut.

FIG. 13 is a schematic diagram of a wear detecting portion showing a state in which lining wear has progressed until a first-stage conductor is cut.

FIG. 14 is a diagram for explaining pad life calculation performed after the first-stage conductor is cut.

FIG. 15 is a flowchart of pad life calculation performed after the first-stage conductor is cut.

FIG. 16 is a schematic diagram of a wear detecting portion showing a state in which lining wear has progressed until a second-stage conductor is cut.

FIG. 17 is a diagram for explaining pad life calculation performed after the second-stage conductor is cut.

FIG. 18 is a schematic diagram of a wear detecting unit showing a state in which lining wear has progressed until a third-stage conductor is cut.

FIG. 19 is a diagram for explaining pad life calculation performed after the third-stage conductor is cut.

FIG. 20 is a flowchart of pad life calculation and warning generation performed after the third-stage conductor is cut.

FIG. 21 is a schematic diagram of a wear detecting portion constituting a third example of the embodiment of the present invention.

FIG. 22 is a partial cross-sectional view showing one example of a wear indicator used for implementing the prior invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 pad 2 back plate 3 lining 4 mounting hole 5, 5 a wear indicator 6, 6 a holding cylinder 7 compression spring 8, 8 a holder 9 conductor 10 disk 11, 11 a detection circuit 12 distance measuring means 13 arithmetic unit 14 display unit 15, 15 a 15b, 15c conductor 16 friction surface 17 temperature sensor 18 brake sensor 19 reset switch 20 wear ratio maintaining switch 21 ignition switch

Claims (8)

[Claims] 1. A conductor which is cut in a process in which a lining of a brake element is worn, a detection circuit which detects a cut of the conductor and sends a disconnection signal, and measures a traveling distance of a vehicle to generate a distance signal. A wear ratio representing a ratio of a wear amount of the lining to a travel distance is obtained based on the distance measuring means to be sent out, and the disconnection signal and the distance signal, and further, the wear ratio and the remaining of the lining when the conductor is disconnected are determined. A calculator for calculating the life of the brake element based on the amount, an indicator for displaying the life calculated by the calculator, the travel distance and the wear ratio stored in a storage unit in the calculator. And a reset switch for erasing all data indicating that the disconnection signal has been sent,
Life indicator for vehicle brake elements. 2. In addition to the reset switch, on the condition that the reset switch is not operated, the wear ratio is represented by data representing the travel distance, the wear ratio, and the fact that the disconnection signal has been sent. 2. The life indicator of a brake element for a vehicle according to claim 1, further comprising a wear ratio holding switch for erasing data indicating a travel distance and a fact that a disconnection signal has been sent, excluding data. 3. A conductor which is cut in the process of wear of the lining of the brake element, a detecting circuit which detects that the conductor is cut and sends out a disconnection signal, and measures a traveling distance of the vehicle to generate a distance signal. A wear ratio representing a ratio of a wear amount of the lining to a travel distance is obtained based on the distance measuring means to be sent out, and the disconnection signal and the distance signal, and further, the wear ratio and the remaining of the lining when the conductor is disconnected are determined. A calculator for calculating the life of the brake element based on the quantity, an indicator for displaying the life calculated by the calculator, and the brake element based on a change in a signal sent from the detection circuit to the calculator. And a replacement detecting means for detecting that the brake element has been replaced, and wherein the computing unit comprises: when the replacement detecting means detects that the brake element has been replaced, A service life display device for a vehicle brake element, having a function of erasing all data indicating the running distance, the wear ratio, and the fact that the disconnection signal is sent stored in a storage unit. 4. A wear ratio holding switch is provided, and when the wear ratio holding switch is operated, the arithmetic unit calculates the travel distance, the wear ratio, and data indicating that the disconnection signal has been sent. 4. The life indicator for a vehicle brake element according to claim 3, further comprising a function of deleting data indicating a traveling distance and a fact that a disconnection signal has been sent, except for data indicating a wear ratio. 5. A plurality of conductors are installed at different positions in the thickness direction of the lining, whereby the amount of wear of the lining can be detected in a plurality of stages by the detection circuit. The wear ratio between the lining wear amount and the travel distance is determined based on the wear amount and the travel distance between the time when the conductor is cut and the time immediately before another conductor is cut, and the wear ratio is determined. 5. The life indicator of a brake element for a vehicle according to claim 1, wherein the life of the brake element is calculated based on a ratio and a remaining amount of the lining when the conductor is newly cut. . 6. After the new brake element is mounted, until the conductor is cut for the first time, the brake is determined based on a preset wear ratio and a signal indicating a travel distance sent from the distance measuring means. The device for displaying the life of a vehicle brake element according to claim 1, wherein the life of the element is calculated. 7. A temperature sensor for detecting a temperature of a portion related to a temperature of a friction surface of the lining at the time of braking is provided, and the higher the temperature detected by the temperature sensor, the longer the life of the brake element is provided to the arithmetic unit. 7. The device for indicating the life of a vehicle brake element according to claim 1, wherein a correction for shortening the calculation is added. 8. A brake sensor for measuring the number of times the brake pedal is depressed is provided, and the more the number of times the brake pedal is depressed, the more the arithmetic unit is corrected to calculate the shorter the life of the brake element. A vehicle life indicator for a vehicle brake element according to claim 1.