JPS6288861A - Belt slip amount detecting device - Google Patents

Abstract

PURPOSE:To simplify wiring of a belt slip detecting device by extracting two signal components for calculating the slip amount of a belt connecting a vehicle engine and a driven rotary body out of a single signal line called a battery line. CONSTITUTION:The plus terminal of a battery 10 is connected to a battery line 14 while the minus terminal is grounded. Electric load 12 including ignition system and electronic fuel injection system is connected to the battery line 14. Further, an alternator regulator 13 for supplying power to both the battery 10 and the vehicle's electric load 12 is connected to the battery line 14. A control device 15 is mainly composed of a microprocessor 16, a memory 17 and an input-output interface 18. To the input-output interface 18 are inputted voltage signals of the battery line 14 through a wave-shaping circuit, a differential amplifier, an analog-digital converter, etc. Accordingly, two signal components for computing the amount of belt slip can be extracted from the voltages of the battery line 14.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a belt slip amount that detects the slip amount of a belt that connects a vehicle engine and a slave rotating body such as an alternator that rotates as the engine rotates. Regarding a detection device.

[Traditional background]

BACKGROUND ART Conventionally, in automobiles, an engine is mounted to drive an engine cooling fan and a driven rotating body of an alternator via a fan belt. Therefore, if the fan belt slips, not only will the fan not be able to rotate sufficiently, causing overheating of the engine, but also the alternator will not be able to rotate sufficiently, resulting in insufficient charging of the storage battery. For this reason, slip amount detection devices have been proposed for detecting fan belt slippage and taking appropriate measures such as issuing an alarm.

[Conventional technology]

As such a slip amount detection device, for example, there is a device as shown in FIG.
52-26302). In this figure, 1 is a first input terminal to which a first pulse signal with a frequency proportional to the rotational speed of an alternator (not shown) as a driven rotating body is applied, and 2 is a first input terminal with a frequency proportional to the engine rotational speed. 2 is a second input terminal to which a pulse signal is applied; 3 is a first waveform shaping circuit that shapes the waveform of the if pulse signal; 4 is a second waveform shaping circuit that shapes the pulse signal of the engine rotation speed; be. This device constitutes a slave rotation detector that detects the rotation speed of the alternator by a first waveform shaping circuit 3 that shapes the waveform of a first pulse signal applied to the first input terminal l, and also constitutes a slave rotation detector that detects the rotation speed of the alternator. It has a shaft rotation detector that detects the rotational speed of the engine using a second waveform shaping circuit 4 that shapes the waveform of a second pulse signal applied to the input terminal 1. 5 is a comparison control circuit which receives the output signal of the second waveform shaping circuit 4 as an input and generates a gate signal for setting the time for counting pulses of the first pulse signal and also generates a reset signal thereof; 6 is the comparison control circuit which generates a reset signal thereof; 1st
a counter circuit that counts the pulses of the shaped signal of the pulse signal while the gate is open by the gate signal and generates a pulse when the count value exceeds a predetermined value;
8 is a conversion circuit that generates an output signal when a pulse is generated from the counter circuit 6; 8 is an alarm circuit that issues an alarm when the output signal disappears from the conversion circuit 7; It constitutes a comparison means for comparing the detection signals from both detectors, and the conversion circuit 7 and the alarm circuit 8 constitute an alarm means.

In this way, this belt slip detection device detects the engine rotation speed and the alternator rotation speed, compares them, and issues an alarm when the amount of belt slip exceeds a predetermined value.

[Problem that the invention seeks to solve]

By the way, in such a belt slip amount detection device, a detection signal corresponding to the rotational speed of the engine and a detection signal corresponding to the rotational speed of a driven rotating body such as an alternator are extracted from separate signal lines. It has become. In other words, the detection signal corresponding to the engine rotation speed is detected based on the primary voltage of the ignition coil, which is connected and disconnected in synchronization with the rotation of the rotor of the distributor, which is gear-driven from the output shaft of the engine. The detection signal corresponding to the alternator is, for example, detected based on the voltage of one of the stator coils of the alternator.

For this reason, in such conventional devices, it is necessary to wire the engine rotation signal line from the ignition coil etc. to the slip detection circuit, while wiring the alternator rotation detection signal line from the alternator to the slip detection circuit, making the wiring complicated. There is a problem with becoming.

Therefore, an object of the present invention is to simplify the wiring of a belt slip detection device.

[Means for solving problems]

In order to solve the above-mentioned problems and achieve the object, the present invention includes a voltage signal detection means for detecting a voltage signal of a buff battery line, and a voltage signal detection means for detecting a signal component corresponding to the rotation of the engine based on the voltage signal detection means. a second signal component detection means for detecting a signal component corresponding to the rotation of an alternator driven by a belt from the engine based on the voltage signal detection means; A slip amount calculation means is provided for calculating the slip amount of the belt based on the signal component detection means.

[Effect]

The present invention detects the voltage of the puff belt line, extracts a signal component corresponding to the rotation of the engine and a signal component corresponding to the rotation of the slave rotary body included in this voltage signal, and detects the slippage of the belt based on these extracted signal components. By calculating the amount, the calculation result is appropriately processed at a later stage. In this way, the present invention can extract the two signal components necessary for calculating the amount of belt slip from a single signal line called the battery line.

〔Example〕 Hereinafter, embodiments of the present invention will be used based on the accompanying drawings.

FIG. 1 shows an example of a belt slip detection device according to the present invention. 10 is a battery, and ten terminals of this eight battery 10 are connected to a battery line 14, and one terminal is grounded.

12 is a vehicle electrical load including an ignition device and an electronic fuel injection device, and is connected to the puffer line 14. Reference numeral 13 denotes an alternator/regulator that supplies electricity to the puffer belt 10 and the vehicle electrical load 12, and is connected to the puffer belt line 14.

Reference numeral 15 denotes a control device, which is mainly composed of a microprocessor 16, a memory 17, and an input/output interface 18. The input/output interface 18 receives the voltage signal of the battery line 14 through a waveform shaping circuit, a differential amplifier circuit, an A/
It is input via a D converter or the like.

Incidentally, the voltage signal of the battery line changes depending on the charging/discharging state of the battery itself, the vehicle electrical load state, the power generation state of the alternator, and the like. Since the configuration of the alternator is as shown in Figure 2, the output of the alternator has a waveform obtained by rectifying the three-phase alternating current as shown in Figures 3 (a) and (b). Ripple appears in its output voltage signal. Therefore, since the battery line voltage signal includes ripples that correspond to the rotation of the alternator, by detecting this ripple, it is possible to extract the signal component that corresponds to the rotation of the alternator. FIG. 3(C) is an example of the voltage signal of the battery line, and it can be seen that the above-mentioned ripple is included. On the other hand, the ignition device, electronic fuel injection device, etc. are electrical loads that operate according to the rotation of the engine. Therefore, in a vehicle equipped with an ignition system or an electronic fuel injection system, the
) As shown in (b), the voltage signal of the pufferette line 14 includes a signal component corresponding to the rotation of the engine, so by detecting this, the signal component corresponding to the rotation of the engine can be extracted. Therefore, R of memory 17
The OM stores in advance the voltage change waveform of the battery line 14 due to the load current of the ignition device and the load current of the electronic fuel injection device as a reference voltage waveform. The voltage signal of the battery tin 14 inputted by
A signal component corresponding to the rotation of the engine is detected by comparing it with the reference voltage waveform stored in the M, and a signal component corresponding to the rotation of the alternator is detected by reading the ripple included in the voltage signal of the pufferite line 14. do.

Then, based on the signal component corresponding to the rotation of the engine and the signal component corresponding to the rotation of the alternator, a ratio between the rotation period of the engine and the rotation period of the alternator is calculated, and whether the ratio is within a predetermined range. judge whether That is, microprocessor 16 connects battery line 14
a first signal component detection means for detecting a signal component corresponding to the rotation of the engine based on the voltage signal of the pufferite line; and a second signal component detection means for detecting a signal component corresponding to the rotation of the alternator based on the voltage signal of the pufferite line. In addition to having a function as a means, it also has a function as a slip area calculation means for calculating the slip amount of the fan belt based on each extracted signal component.

When the slip amount of the fan belt calculated by the microprocessor 16, that is, the ratio of the rotation period of the engine to the rotation period of the alternator, exceeds a predetermined range, a warning device 19 issues a belt slip warning.

Next, the operation of this device will be explained based on FIG.

First, the battery line voltage waveform V B (t) is input at Sl.

Next, at 32, the bar 7 telli line voltage waveform v m (t)
A frequency analysis is performed to calculate the ripple frequency f caused by the alternator.

Next, in step 33, the alternator cycle T1 is calculated from the frequency f and the number of ripples Nl per alternator rotation, which is uniquely determined by the alternator.

Next, at 34, the battery line voltage waveform V B (t) is adjusted such that the average voltage level Vn of the battery line voltage waveform V B (t) matches the average level Vs of the reference voltage waveform V S (t) stored in advance. ) is level shifted (VB' waveform in Figure 6).

Next, at 55, the level-shifted battery line voltage waveform VB'' (1) and the pre-collar memory j, C are a certain reference voltage waveform Vs
For example, the square difference is calculated as the distance gld(x) from (t) (waveform d in FIG. 6).

Next, in step 56, the time point at which the load current of the ignition system occurs, that is, the minimum time point ti of the distance d(t) is calculated, and in S7, the period Ti of the minimum time point ti and the number of ignitions per engine 1 @ rotation are calculated. The engine rotation layer JIT2 is calculated from.

Next, in step 58, a ratio α between the alternator rotation period TI and the engine rotation period T2 is calculated, and in S9 it is determined whether the ratio α is within a predetermined range [αo x α x α1].

Next, when it is determined that the determination result is not within the predetermined range, S
Warn with IO.

Note that these steps are performed every predetermined time or every predetermined rotation. Furthermore, although the electric load of the ignition device is used as a component proportional to the rotation period of the engine, the electric load of the electronic fuel injection device may be used as a component proportional to the rotation period of the engine, or it may be determined from the rotation speed instead of the rotation period.

〔Effect of the invention〕

As explained above, according to the belt slip detection device according to the present invention, since the two signal components necessary to calculate the amount of belt slip are extracted from a single signal line called the panteri line, the ignition coil This eliminates the need for wiring to an alternator or the like, simplifying the wiring.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an example of a belt slip amount detection device according to the present invention, Fig. 2 is a block diagram showing a general configuration of an alternator, Fig. 3 is a graph showing the output voltage of the alternator, and Fig. 4 5 is a graph showing the relationship between the battery line voltage and the main consumption groove of the ignition device, FIG. 5 is a 70-chart explaining the operation of the belt slip amount detection device example shown in FIG. 1, and FIG. 7 is a graph showing voltage signal processing in the belt slip amount detection device example shown in FIG. 7, and FIG. 7 is a block diagram showing a conventional belt slip amount detection device. 14... Battery line 15... Control device 16... Microprocessor (MPU) 17...
・Memory 18...I/O interface Figure 2 Figure 3 Figure 1 Closed Figure 6 Figure 9

Claims (1)

[Claims] a voltage signal detection means for detecting a voltage signal of the battery line; a first signal component detection means for detecting a signal component corresponding to the rotation of the engine based on the voltage signal detection means;
a second signal component detection means for detecting a signal component corresponding to rotation of an alternator driven by a belt from the engine based on the voltage signal detection means;
What is claimed is: 1. A belt slip amount detection device characterized by comprising a slip amount calculation means for calculating the slip amount of the belt based on the signal component detection means.