JPH0381018B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a brake safety device for automobiles, etc., and is applied to detecting an abnormal temperature rise in brake oil and detecting the wear limit of a brake lining. The present invention relates to a wear degree detection method.

Configuration of the conventional example and its problems In the conventional example, as shown in FIG. Are known. As shown in FIG. 2, this sensor 7 has a structure in which both ends of a metal wire 8 are connected to external lead wires 10 and 10b, and these are placed in a resin 9. By arranging this sensor 7 in such a way that its tip is embedded in the brake lining 1 via the back metal 2 of the brake lining 1, the tip of the sensor 7 changes as the brake lining 1 wears. The structure is such that the wear limit is detected when the metal wire 8 provided in the resin 9 breaks.

In FIG. 1, 3 is a wheel cylinder section, 4 is a piston that moves according to the degree of wear of the brake lining 1, 5 is brake oil, and 6 is a rotor. Further, A indicates the initial position of the brake lining 1, and B indicates the position at the wear limit.

However, this method only detects the wear limit of the lining and has the disadvantage that it is a disposable sensor.

Therefore, from the safety aspect of the brake system, vapor lock (due to abnormal temperature rise of the brake oil) that occurs due to overuse of the brakes,
Air bubbles form inside and the brakes become inoperable)
In order to prevent this, a detection method that has both the function of detecting the wear limit of the brake lining and the function of detecting an abnormal temperature rise of the brake oil has been desired.

OBJECTS OF THE INVENTION The present invention seeks to provide a method for detecting brake temperature and degree of wear that has both the functions of detecting the wear limit of a brake lining and detecting an abnormal temperature rise of brake oil.

Structure of the Invention The brake temperature and wear degree detection method of the present invention includes a sensor placed at a predetermined location in the wheel cylinder of the brake, and this sensor detects the position of the piston that moves as the brake lining wears. This sensor detects the wear limit by contact, and at the same time detects the abnormal temperature of the brake oil.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 3, 4, and 5, with the same numbers assigned to the same parts as in the conventional example. The sensor 11 according to the present invention is installed at a predetermined position in the wheel cylinder part 3 of the brake, as shown in FIG. It also has the ability to detect. The structure of this sensor 11 includes, for example, a proximity switch as a sensor for detecting positional changes depending on the presence or absence of the piston 4, a magnetic resistance element, as shown in FIG.
A non-contact sensor 12 such as a photoelectric switch and a heat sensitive element 13 such as a thermistor or thermocouple serving as a sensor for detecting the temperature of brake oil 5 are integrated into a sensor case 14.

Next, the operating characteristics of this sensor will be explained. The above-mentioned sensor 11 is installed in the wheel cylinder part 3 of the brake, and by utilizing the fact that the piston 4 moves forward due to wear of the brake lining 1, the piston 4 moves forward until the wear limit of the brake lining 1 is reached. It is installed at a position where the non-contact position sensor 12 operates when For example, if the non-contact position sensor 12 is a proximity switch, the piston 4 will be at the proximity switch position and in the shot state until the brake lining 1 reaches its wear limit, and at this time an abnormal temperature rise in the brake oil 5 will be detected. can be detected by the heat-sensitive element 13 provided on this sensor 11. On the other hand, when the brake lining 1 reaches its wear limit, the piston 4 moves forward, and the piston 4 moves away from the position of the proximity switch, resulting in an open state, and the wear limit of the brake lining 1 can be detected. In Figure 3, C and D are brake lining 1
indicates the position of the piston 4 at the initial stage and at the wear limit. Regarding the internal structure of the sensor, it is also possible to separately design a configuration that detects when the non-contact position sensor 12 enters the short state due to the movement of the piston 4 at the wear limit of the brake lining 1. .

Now, as shown in FIG. 5, when the brake is used continuously, the temperature of the sensor 11 increases due to wear heat, and when the temperature reaches a predetermined dangerous temperature, the output of the heat-sensitive element 13 as a temperature sensor is transferred to the comparator circuit 15 and the lamp drive. A lamp 17 is turned on through a circuit 16. Further, when the brake lining reaches its wear limit, a signal from a non-contact position sensor 12 integrated into the sensor 11 lights up a lamp 17 via a lamp drive circuit 16 to issue an alarm. This allows one sensor 11 to measure both brake temperature and wear limit.

Effects of the Invention () The sensor of the present invention has a function of non-contact detection of the wear limit of the brake lining by utilizing the movement of the piston position due to wear of the brake lining, and a function of detecting abnormal temperature rise of the brake oil. The present invention provides a method for easily detecting brake temperature and degree of wear by having both a temperature sensor function and a detecting temperature sensor function.

() Since the wear limit of the brake lining is detected using the change in position due to the movement of the piston, the sensor is not disposable and can be used semi-permanently even if the brake lining reaches its wear limit.

() When informing the driver of an abnormal temperature rise in the brake oil or the wear limit of the brake lining by displaying a lamp, etc., the circuit configuration can be extremely simple, making it possible to configure a very inexpensive and practical detection system. I can do it.

[Brief explanation of drawings]

FIGS. 1 and 2 are configuration diagrams showing a conventional sensor for detecting the wear limit of a brake lining, FIGS. 3 and 4 are configuration diagrams showing the mounting state of the sensor for explaining the present invention, and FIG. The figure is also a block diagram of a detection circuit for explaining the present invention. 1... Brake lining, 3... Wheel cylinder section, 4... Piston, 5... Brake oil, 11... Sensor.

Claims (1)

[Claims] 1. A sensor is placed at a predetermined location in the wheel cylinder part of the brake, and the sensor detects the degree of wear of the brake lining by non-contact detection of changes in the position of the piston, and also detects the temperature of the brake oil. Features brake temperature and wear detection method.