JPH039089Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention continuously detects the states of various physical quantities, and when the change in the physical quantity deviates from a predetermined range,
The present invention relates to a physical state detection device that automatically sends out warnings.

Conventional physical quantity measuring devices or detection devices indicate the current physical quantity or continuously record the physical quantity that changes one after another, and check whether the physical quantity is within a predetermined range. The only way to determine whether or not to do so is to manually judge based on the instruction and recording conditions.If an abnormality occurs in the equipment, equipment, parts, etc. targeted for physical quantity detection, the abnormality can be detected in advance and automatically based on changes in the physical quantity. This results in defects that cannot be detected.

The purpose of this invention is to eliminate such drawbacks of the conventional methods at once, and includes a signal generating means SS, SEL, ADC that sequentially converts physical quantities that change sequentially into electrical signals at a predetermined timing and outputs the electrical signals. Switching circuit SW that switches the electrical signal between the first output and the second output
a holding circuit MM that inputs an electrical signal output from the signal generating means to update and store the already stored contents when the switching circuit is switched to the first output; and a switching circuit. is switched to the second output, inputs the electrical signal output from the signal generating means, compares this current input electrical signal with the electrical signal held in the holding circuit, and calculates the current input electrical signal. Comparators CP1 and CP2 output an in-range signal when the difference between the signal and the electrical signal held in the holding circuit is within a predetermined range, and output an out-of-range signal when the difference is outside the predetermined range. A switching control means LAT2 that switches the switching circuit that is always switched to the second output to the first output when an in-range signal is output, and a circuit G3 that outputs an alarm signal when the comparator outputs an out-of-range signal. The present invention provides an extremely effective physical state detection device that detects the physical quantity immediately before an abnormality occurs in the object to be detected, and at the same time automatically notifies that the object is in a state that is in advance of causing a failure. .

Hereinafter, details of the present invention will be explained with reference to block diagrams showing embodiments.

In the figure, sensors SS such as microphones and strain gauges that convert physical quantities into electrical signals are shown.
The output of is given to a plurality of band wavers BPF ₁ to BPF _o , each having a different passing frequency band, and divided into components for each frequency band, and then a selector that operates according to the timing pulse Pt from the pulse generator PG.
SEL sequentially and iteratively selects and converts the selected output to an analog-to-digital converter (hereinafter referred to as
ADC) After converting into a digital signal by A/D, it is applied to comparison inputs A of comparators CP ₁ to _{CP 3} via a switching circuit SW.

On the other hand, initial values are stored in each address of the memory MM as a holding circuit in correspondence with the bandpass filters BPF ₁ to BPF _o , and these are the timing pulses.
The latch circuit LAT is sequentially read out by the addressing signal Sa sent out from the pulse generator PG in synchronization with Pt, and is output by the latch circuit LAT according to the latch pulse Pl ₁ which is extracted by differentiating the leading edge of the timing pulse Pt by the differentiating circuit DF ₁ . ₁ , and the content of this is added by the bias circuit BAS ₁ for determining the upper limit value of a predetermined range, and a bias +a in the upper limit direction is added, and the bias circuit BAS 1 for determining the lower limit value of the predetermined range is added. A bias -a in the lower limit direction is added by the circuit BAS ₂ , and is applied to the reference input B of the comparators CP ₁ and CP ₂ .

For this reason, the ADC that converted the current physical quantity
The output of the A/D and the initial value to which biases +a and -a are added are compared by each comparator CP ₁ and CP ₂ , and in the comparator CP ₁ , under the condition of reference input B>comparison input A In the case of BA, the comparison output becomes, for example, "L" (low level), and in the case of BA, the comparison output becomes, for example, "H" (high level).In the comparator CP ₂ , under the condition of reference input B<comparison input A, the comparison output becomes "L" (low level). Since the comparison output is set to be, for example, "H" when is "L" and BA is "L", if the output of ADC/A/D is within a predetermined range with respect to the initial value, each comparison output will be The signal becomes "L", is inverted by NOR gate _G1 , becomes "H", and is sent to inhibit gate _G2 .

Also, in comparator CP ₃ , to comparison input A
The output of ADC/A/D is given, and each reference input C
and B includes a reference value circuit E ₁ that generates a signal corresponding to the absolute upper limit value of the physical quantity, and a reference value circuit E 1 that generates a signal corresponding to the absolute lower limit value of the physical quantity.
E ₂ is given, and reference input B < comparison input A
<Under the condition of reference input C, the comparison output is set to be, for example, “L”, and under the conditions of BA or CA, the comparison output is set to be, for example, “H”, so the output of ADC/A/D is an absolute value. If it is within the upper and lower _limits of
The output of _G1 is sent to the latch circuit _LAT2 via the inhibit gate _G2 .

The latch circuit LAT ₂ holds the output of the inhibit gate G ₂ according to the latch pulse Pl ₂ obtained by differentiating the trailing edge of the timing pulse Pt by the differentiating circuit DF ₂ , and in this example, the holding content is “H”. In order to drive the switching circuit SW at this time, the output of the ADC/A/D corresponding to the current physical quantity is given to the memory MM, and the contents are updated and stored at the address specified by the address designation signal Sa.

For this reason, in synchronization with the operation of selector SEL, it responds to the current physical quantity divided for each frequency band.
The outputs of the ADC/A/D are sequentially and repeatedly stored in the addresses corresponding to the bandpass filters BPF ₁ to BPF _o of the memory MM, and the stored values are given to the latch circuit LAT ₁ as the next reference value. This is the value obtained by converting the previous physical quantity, and is compared with the value obtained by converting the current physical quantity at the next point in time.
If the comparison result is within the specified range, the memory MM
and repeat these operations.

Regarding the above, if the output of ADC/A/D deviates from the predetermined range, the comparison output of comparator CP ₁ or CP ₂ changes to "H" and the output of NOR gate G ₁ becomes "L". If the output of the inhibit gate _G2 also becomes "L" or the output of the ADC/A/D deviates from the absolute upper and lower limit range, the output of the comparator _CP3 becomes "H" and the inhibit gate _G2 turns off, and in this case as well, the output of the same gate _G2 becomes "L", so the switching circuit SW is not driven, and the ADC/A/D that converted the current physical quantity
_The output _of
Since it is sent out as an alarm signal AL via the gate _G3 and the pulse generator PG stops operating in response to the alarm signal AL, the value obtained by converting the immediately previous physical quantity is held in the memory MM.

Therefore, it is automatically notified that an abnormality has occurred in the target physical quantity, and if the contents of the memory MM are read out and processed by the computer CPU,
The data immediately before a physical quantity becomes an abnormal value is obtained for each frequency band, and by appropriately setting a predetermined range and absolute upper and lower limits, it is possible to repair the target part before a complete failure occurs in equipment, equipment, etc. can be done.

However, the sensor SS is a microphone,
In addition to strain gauges, any device that converts a physical quantity into an electrical signal, such as a temperature sensor, pressure sensor, or flow rate sensor, can be used depending on the conditions.
The same applies to items that are selected sequentially and repeatedly using SEL, and are configured using analog circuits.
ADC/A/D can also be omitted.

Further, instead of the memory MM, counters, accumulators, etc. may be used, and a number of these items corresponding to the number of inputs of the selector SEL may be provided, and each gate G ₁ to
The present invention can be modified in various ways, such as replacing _G3 with another gate circuit depending on conditions.

As is clear from the above explanation, the present invention continuously and automatically detects the physical state of equipment, equipment, etc., issues an alarm just before the state changes, and maintains the current value. It is possible to save labor in life determination, maintenance, and operation of equipment, parts, etc., and it is particularly effective when applied to large machine tools, dental grinders, etc.

[Brief explanation of the drawing]

The figure is a block diagram showing an embodiment of the present invention. SS...Sensor, BPF ₁ to BPF _o ...Bandwidth wave device,
SEL...selector, A/D...ADC (analog/
digital converter), SW...switching circuit, MM...
...Memory (holding circuit), CP ₁ to _{CP 3} ...Comparator,
BAS ₁ , BAS ₂ ...Bias circuit, _E1 , _E2 ...Reference value circuit, _G3 ...OR gate (gate circuit).

Claims (1)

[Claims for Utility Model Registration] Signal generating means that sequentially converts physical quantities that change sequentially into electrical signals at predetermined timings and outputs them, and a switching circuit that switches the input electrical signals to a first output and a second output. and a holding circuit that inputs the electric signal output from the signal generating means when the switching circuit is switched to the first output and updates and stores the already stored contents; inputting the electrical signal output from the signal generating means when the switching circuit is switched to the second output, and comparing this current input electrical signal with the electrical signal held in the holding circuit; Outputs an in-range signal when the difference between the current input electrical signal and the electrical signal held in the holding circuit is within a predetermined range;
A comparator that outputs an out-of-range signal when it is outside a predetermined range, and a second one that always outputs an in-range signal when the comparator outputs an in-range signal
a switching control means for switching a switching circuit that has been switched to an output of 1 to a first output; and a circuit that outputs an alarm signal when the comparator outputs an out-of-range signal. Device.