JPH0422803Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an oil filter clogging alarm device, particularly to an oil filter clogging alarm device for purifying engine oil of an automobile.

BACKGROUND OF THE INVENTION Lubricating engine oil used in automobile engines is sent to each sliding part of the engine by an oil pump through an oil filter, and is purified by removing foreign substances from the oil filter. A filter element made of paper or fiber is disposed within the oil filter, and contaminants such as dust, carbon particles, or oxides generated due to oil deterioration adhere to this filter element. When the engine is used for a long period of time, a large amount of contaminants adhere to the filter element, and the oil filter becomes less efficient due to the clogging of the filter element. Therefore, the oil filter attached to the engine is replaced with a new oil filter periodically or after long-term use. In addition, a relief valve is installed inside the oil filter, and even if the filter element becomes clogged, the relief valve opens and allows bypass oil to flow directly to each sliding part of the engine without letting oil pass through. method is adopted.

Problems to be Solved by the Invention By the way, conventionally, automobiles have not been equipped with a device that indicates the clogging status of the oil filter, and after driving the automobile for a certain period of time, the driver periodically or The oil filter was replaced when it had turned black due to contaminants. With such a replacement method, it is not possible to correctly recognize the appropriate time to replace the oil filter. Therefore, even if the filter element is clogged with a large amount of contaminants to the extent that the oil filter cannot function properly, the driver will not be able to detect this deterioration and will not be able to continue driving the vehicle without replacing the oil filter. may be driven continuously. It is clear that such operating conditions significantly shorten the life of the engine. Further, contrary to the above case, the oil filter may be replaced even if the oil filter is not very clogged, and such a case is very uneconomical. Therefore, there is a need for a device that accurately informs the driver of the clogging state of the oil filter.

Therefore, as shown in, for example, Japanese Utility Model Application Publication No. 58-2309, an engine oil filter clogging warning device has been proposed. This alarm device is provided with a relief valve on the oil filter that opens when the oil filter is clogged, and activates the clogging alarm device with an activation signal from a bypass switch that is turned on when the relief valve is opened.
A feature of the present invention is that when the coolant temperature is lower than a set value by means of a water temperature detecting means that detects the coolant temperature of the engine, the actuation signal for the bypass switch is invalidated. However, the conventional clogging alarm system detects the engine cooling water temperature and activates the alarm system, so when there is a temperature difference between the engine cooling water and the engine oil, the oil Since the viscosity of the oils differs, the clogging state cannot be accurately indicated by the above-mentioned alarm device.

Therefore, as shown in Japanese Utility Model Application Publication No. 56-52009, for example, a hydraulic oil safety device has been proposed that measures the oil temperature and detects the oil pressure when the oil temperature reaches a set value or higher. has been done. However, this device does not allow for gradual display of oil pressure at different levels.

The object of this invention is to provide an oil filter clogging alarm device that accurately indicates different levels of clogging conditions.

Means for Solving Problems The oil filter clogging alarm device according to this invention includes a temperature sensor that detects the temperature of oil passing through a filter element disposed in the oil filter, and a temperature sensor that detects the temperature of oil passing through a filter element disposed in the oil filter. , a comparison circuit connected to the temperature sensor and the pressure sensor, and an alarm device having a plurality of light emitting diodes activated by a display output signal of the comparison circuit. a comparison circuit connected to the temperature sensor and the pressure sensor, and a gate circuit for detecting that the oil exceeds a predetermined temperature and a different level of pressure;
The display device includes a switching circuit that selectively lights up the plurality of light emitting diodes by generating different display output signals based on the output of the gate circuit in response to different levels of pressure.

Function When the engine oil flowing through the oil filter exceeds a predetermined temperature and exceeds different levels of pressure, display output signals are selectively applied to multiple light emitting diodes, allowing the driver to see different levels of clogging status in stages. can be recognized accurately and accurately.
Further, since the plurality of light emitting diodes are selectively turned on by the switching circuit, when one light emitting diode is turned on, the other light emitting diodes are turned off.

Embodiment Hereinafter, an embodiment of this invention will be described with reference to FIGS. 1 to 4. As shown in FIG. 1, in the oil filter clogging alarm device 10 of this invention, a cylindrical filter element 12 is fixed in a case 11, and an outer chamber 13 and an inner chamber are formed on the outside and inside of the filter element 12, respectively. 14 are formed. An upper wall 15 provided on the upper part of the case 11 is heated by a pump (not shown).
An inlet 16 is formed through which oil flows into the outer chamber 13 from the outside. The inner chamber 14 is connected to each sliding part from an outlet 17 provided on the central axis of the case 11. At the bottom of the filter element 12,
Relief valve 1 protruding inward into inner chamber 14
8 is provided. The relief valve 18 has a valve body 20 slidably disposed within the cylindrical sleeve 19.
and a spring 2 that presses the valve body 20 in the valve closing direction.
1, and a stopper 22 formed at the end of the sleeve 19 to prevent movement of the valve body 20. The sleeve 19 is provided with an outer chamber 1 without passing the filter element 12 when the valve body 20 moves in the valve opening direction.
A relief port 22 is provided that allows oil to flow directly from 3 to the inner chamber 14.

A rod 26 is provided adjacent the valve body 20 to detect movement of the valve body 20. That is, the pressure sensor 23 includes a sensor body 24 fixed to the lower end of the case 11 by screw connection, and a rod 26 slidably disposed in a hole 25 formed in the sensor body 24.
and the end wall 35 of the enlarged portion 34 of the hole 25 and the rod 26.
The rod 26 is disposed between the flange portion 36 of the rod 26
the rod 2 so that the tip 32 of the rod is in contact with the valve body 20.
6 and a plurality of contact points 28 to 31 of a contact type switch attached to the sensor body 24 around the rod 26. rod 2
6 is made of non-conductive material, while the rear end 33 is
Made of conductive material. Contact 28 is connected to a power supply voltage, and other contacts 29 to 31 are connected to a comparison circuit described later.

In the above configuration, oil flowing from the inlet 16 of the oil filter 10 normally flows into the outer chamber 1.
3 through the filter element 12 and the inner chamber 14 and exits from the outlet 17. When the filter element 12 becomes clogged, the pressure in the outer chamber 13, which is higher than that in the inner chamber 14, causes the valve body 20 to move inward against the elasticity of the spring 21, causing oil to flow into the relief port. Outer chamber 1 through 22
3 directly into the inner chamber 14. As the valve body 20 moves, the rod 26 also moves, and the contacts 28 and 29 are first electrically connected by the conductive material 33. When the pressure in the outer chamber 13 becomes higher, the valve body 20 also moves further, and the contacts 30 and 31 successively conduct to the contact 28.

The embodiment of the pressure sensor 23 described above can be modified. For example, the spring 27 may be omitted and the tip 32 of the rod 26 may be fixed, pivoted, or connected to the valve body 20 by a universal joint. Also, oil filter 10
Since the pressure sensor 40 is replaced after clogging, another embodiment of this invention is to install a pressure sensor 40 in the part that will not be replaced.
It is also possible to provide As shown in Figure 1,
The pressure sensor 40 is located in the pressure detection chamber 4 of the detection member 39.
A piezoelectric transducer 42 disposed in a high-pressure chamber 43 and a low-pressure chamber 44 by fixing the piezoelectric transducer 42
, a high pressure port 47 that leads the oil pressure upstream of the filter element 12 to the high pressure chamber 43 , and a low pressure port 48 that leads the oil pressure downstream of the filter element 12 to the low pressure chamber 44 . As the piezoelectric conversion element 42, a piezoelectric rubber, a bulk element, a PN junction element (pressure-sensitive diode or transistor), or a dielectric crystal that utilizes the piezo effect can be used. Piezoelectric conversion element 4
2 converts the pressure difference between the high pressure chamber 43 and the low pressure chamber 44 into an electrical signal.

Other pressure sensors 50, for example, as shown in FIG.
1 and a magnetically sensitive element 52 can be used.
The magnetically sensitive element 52 can be a magnetically sensitive diode or a Hall element. The magnet 51 is fixed to the valve body 20, and the magnetically sensitive element 52 is fixed to the sensor body 24 or the sleeve 19. These magnets 51 and magnetically sensitive elements 52 are reversely connected to the sensor body 24.
It may also be fixed to the valve body 24. Further, as shown in FIG. 3, the pressure detection chamber 41 of the detection member 39
By fixing a magnet 51 to a diaphragm 53 fixed with spacers 45 and 46 inside the high pressure chamber 4
Since the diaphragm 53 is deformed due to the pressure difference between the pressure chamber 3 and the low pressure chamber 44, this deformation can be converted into an electric signal by the magnetic sensing element 52 as the amount of movement of the magnet 51. The pressure sensor 50 may detect the difference between the oil pressure upstream of the filter element 12 and atmospheric pressure.

FIG. 4 shows a circuit diagram of the oil filter clogging alarm device of this invention. The illustrated oil filter clogging alarm device detects the temperature of oil passing through a filter element 12 disposed in an oil filter 10, and includes a temperature sensor 60 disposed in an oil flow path. A pressure sensor 50 that detects the oil pressure upstream of the filter element 12, and a comparison circuit 62 that is connected to the temperature sensor 60 and the pressure sensor 50 and generates a display output signal when the oil exceeds a predetermined temperature and pressure. and an alarm device 63 activated by the display output signal of the comparison circuit 62. The pressure sensor 40 described above can also be used instead of the pressure sensor 50.

Temperature sensor 60 is connected to an inverting input terminal of differential amplifier 65 via amplifier 64, and a reference voltage power supply 96 is connected to its non-inverting input terminal.
The output of the differential amplifier 65 is connected to the three AND gates 6 that together with OR gates 93 and 94 constitute a gate circuit.
6, 67 and 68 input terminals. The input of the magnetically sensitive element 5 of the pressure sensor 50 is connected to the amplifier 70.
It is connected to three constant voltage diodes 71, 72 and 73 via. These constant voltage diodes 7
1 to 73 are set so that the voltage level at which conduction is made becomes higher in sequence. Each constant voltage diode 71-7
3 is connected to the bases of transistors 74 to 76 as corresponding switching elements. The collectors of each transistor 74-76 are connected to an ignition switch 69, and the emitters thereof are connected to AND gates 66-68 and grounded via respective resistors 77-79. 1st
The contacts 29 to 31 in the figure are connected to each transistor 74.
~76 or directly connected to AND gates 66-68. It will be obvious to those skilled in the art that the above circuit can be modified as appropriate depending on the characteristics of the pressure sensor or switching element. Voltage P obtained through ignition switch 69 is applied to terminal 28 of pressure sensor 23 and reset switch 95.

The comparison circuit 62 has a rotation range detection circuit 81 connected to an engine rotation sensor 80, and this rotation range detection circuit 81 generates the display output signal when the engine rotation speed is equal to or higher than a predetermined low rotation speed. It has a function of preventing generation of the display output signal when the engine rotation speed exceeds a predetermined high rotation speed. The rotation range detection circuit 81 includes a D/A converter 82 connected to the engine rotation sensor 80, and a D/A converter 82 connected to the engine rotation sensor 80.
a differential amplifier 83 having an inverting input terminal receiving the output of the converter 82; and a transistor 84 having a collector connected to the output terminal of the differential amplifier 83.
, the base of the transistor 84 and the D/A converter 8
2, and a constant voltage diode 85 connected between the two. The emitter of transistor 84 is grounded, and its collector and the output terminal of differential amplifier 83 are connected to the input terminals of AND gates 66-67. Further, a reference power supply voltage 86 is applied to a non-inverting input terminal of the differential amplifier 83.

The output terminal of each AND gate 66 to 68 serves as a switching circuit for generating a display output signal.
It is connected to the set terminals of flip-flops (RSFF) 87-89. Q output terminals of RSFF87-89 are connected to light emitting diodes (LED) 90-92 of the corresponding alarm device 63,
The display output signal sent from 9 is
It is supplied to LEDs 90-92. The reset terminal of RSFF 87 is connected to the output terminal of AND gate 67 and reset switch 95 through OR gate 93, and similarly the reset terminal of RSFF 88 is connected to AND gate 68 and reset switch 95 through OR gate 94. The reset terminal of RSFF 89 is connected only to reset switch 95.

In the above configuration, when the output of the temperature sensor 60 reaches a predetermined level or higher, the differential amplifier 65 applies an input signal to the AND gates 66 to 68. Further, when the engine rotation speed is equal to or higher than a predetermined low rotation speed, the operational amplifier 83 that receives the output of the engine rotation sensor 80 applies input signals to the AND gates 66 to 67. However, when the engine speed exceeds a predetermined high speed, the constant voltage diode 85 becomes conductive and the transistor 84 is turned on, so that the output of the differential amplifier 83 is not applied to the AND gates 66 to 68.

Next, when the oil filter 10 becomes clogged, the signal from the magnetic sensing element 52 of the pressure sensor 50 becomes high level, first the constant voltage diode 71 becomes conductive, and the transistor 74 turns on. Therefore, when the ignition switch 69 is on, the AND gate 66 produces an output and the RSFF 87 is set, so that the LED 90 lights up. Further, as the clogging progresses, the constant voltage diode 72 becomes conductive, and the LED 91 lights up in the same manner as described above. However, since the output of the AND gate 67 is applied to the reset terminal of the RSFF 87 through the OR gate 93, the LED 90 is turned off. Further, as the clogging condition progresses further, the constant voltage diode 73 becomes conductive, so the RSFF 88 is reset and the LED 91
goes out and the LED 92 lights up. In this way, the LEDs 90 to 92 of the alarm device 63 can display the degree of clogging of the oil filter in stages. All of the LEDs 90-92 can be turned off by turning on the reset switch 95 and resetting the RSFFs 87-89. In this case, the clogging state can be reconfirmed by lighting up the LEDs 90 to 92 again.

Effects of the Invention As mentioned above, in the clogging alarm device of this invention, when the engine oil exceeds a predetermined temperature and different pressure levels, a display output signal is selectively applied to the light emitting diode of the alarm device. Therefore, the driver can recognize the clogging state at different levels step by step and accurately. For this reason,
It becomes possible to predict the clogging state of the oil filter.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an oil filter clogging alarm device showing two embodiments of this invention, and FIG. 2 is a cross-sectional view showing another embodiment of a pressure sensor used in the device of FIG. FIG. 3 is a sectional view showing still another embodiment of the pressure sensor, and FIG. 4 is an electrical circuit diagram connected to the device shown in FIG. 1. 10... Oil filter, 12... Filter element, 60... Temperature sensor, 23, 40, 5
0...Pressure sensor, 62...Comparison circuit, 63...
Alarm device, 66-68...and gate, 69...
...Ignition switch, 71-73... Constant voltage diode, 74-76... Transistor, 8
0...Engine rotation sensor, 81...Rotation range detection circuit, 87-89...RS flip-flop,
90-92...Light emitting diode, 95...Reset switch.

Claims (1)

[Claims for Utility Model Registration] (1) A temperature sensor that detects the temperature of oil passing through a filter element disposed in the oil filter, and a pressure sensor that detects the fluctuating oil pressure upstream of the filter element. , a comparison circuit connected to the temperature sensor and the pressure sensor, and an alarm device having a plurality of light emitting diodes activated by the display output signal of the comparison circuit, the comparison circuit being connected to the temperature sensor and the pressure sensor and including an alarm device having a plurality of light emitting diodes. A gate circuit detects when a predetermined temperature is exceeded and a different level of pressure is exceeded, and the output of the gate circuit generates different display output signals in response to different levels of pressure to selectively activate multiple light emitting diodes. An oil filter clogging alarm device characterized by comprising a switching circuit that lights up. (2) The comparison circuit consists of a comparator that is connected to the temperature sensor and generates an output when the output of the temperature sensor exceeds a certain level, a switching element that is connected to the pressure sensor, and an output of the switching element and the comparator that generates an output when the output of the temperature sensor exceeds a certain level. An oil filter clogging alarm device according to claim (1), which applies a display output signal to the alarm device when a clogging occurs. (3) The oil filter clogging alarm device according to claim 1, wherein the pressure sensor is a contact switch, a piezoelectric transducer, or a magnetically sensitive element. (4) Each of the plurality of switching elements is connected to an ignition switch and a corresponding AND gate, the output of the AND gate is connected to the set terminal of the switching circuit, and the reset terminal of the switching circuit is connected to the An oil filter clogging alarm device according to claim 2, wherein the output terminal of the switching circuit receives the output of the AND gate representing a high pressure signal and is connected to an alarm device. (5) The comparison circuit is an oil filter eye according to claim (1) of the utility model registration claim, which has a rotation range detection circuit that prevents generation of the display output signal when the engine rotation speed exceeds a predetermined high rotation speed. Clogging alarm device.