JPH0332081B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Field of the Invention>> The present invention relates to a temperature regulator that drives a control output element according to a deviation between a detected temperature and a set temperature.
In particular, the present invention relates to an alarm control circuit that operates when the deviation exceeds a predetermined reference range.

<Prior art and its problems> As is well known, the operation mode of the alarm control circuit in a temperature controller is, for example, when the deviation between the detected temperature and the set temperature is too large in the positive direction (when the detected temperature is abnormally high). There are those that issue an alarm output when the deviation is too large in the negative direction, and those that have both of these alarm functions.
Furthermore, there are many types, such as those that combine these with a standby sequence function, and each of these has its own characteristics, and the alarm operation mode that is suitable for it differs depending on the object to be controlled.

However, in conventional temperature controllers, the operation mode of the alarm control circuit is fixed, and the user must select in advance which alarm operation mode is appropriate at the time of purchase. It was not possible to arbitrarily change the alarm operation mode of the device to suit the usage mode.

≪Object of the Invention≫ This invention was made in view of the above-mentioned conventional problems, and its purpose is to improve the conventional alarm operation mode by simply adding a small number of circuits compared to a single temperature controller. It is an object of the present invention to provide a temperature regulator having a circuit configuration that has a large number of alarm operation modes and can arbitrarily switch between these operation modes according to the purpose of use.

≪Means for Solving the Problems≫ In order to achieve the above-mentioned object, the present invention provides a system that responds to the difference between the temperature detection voltage detected by the temperature sensor and the set voltage corresponding to the set temperature output from the temperature setting circuit. a differential amplifier that outputs a deviation voltage; and a differential amplifier that is connected to the output side of the differential amplifier, and
Comparing the deviation voltage output from this differential amplifier and the reference voltage output from the reference voltage generator,
A temperature controller equipped with a comparator that supplies a binary output of on and off to a relay drive circuit, and connected between the output side line of the reference voltage generator, the voltage supply circuit that supplies a predetermined voltage, and the ground. , the first alarm operating point voltage on the high temperature side is determined by the combination of resistors inserted through the first changeover switch group, which is turned on and off according to the alarm operating mode selected from a plurality of alarm operating modes. and the second on the low temperature side
a resistor network that generates an alarm operating point voltage; and a first resistor network that compares the deviation voltage output from the differential amplifier with the first and second alarm operating point voltages.
and a second comparator; connected to the first and second comparators, when the deviation voltage is equal to or higher than the first alarm operating point voltage;
Alternatively, when the voltage is below the second alarm operating point voltage, an alarm signal is output to the first output terminal, and when the deviation voltage is above the second alarm operating point voltage, the alarm signal is output to the first output terminal.
a logic circuit that outputs an alarm signal to a second output terminal when the voltage is below the alarm operating point of the logic circuit;
and a second changeover switch group for selecting and switching one of the second output terminals, and an alarm signal from the first or second output terminal of the logic circuit selected by the second changeover switch group. and an alarm drive circuit that drives the alarm element in response to the above-mentioned changeover switch group, and allows switching and selection of multiple types of alarm operation modes by a combination of on and off of the first changeover switch group and the second changeover switch group. It is characterized by

<<Example>> Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIG. 1, 1 is a temperature sensor, and a temperature detection voltage V _T outputted from this temperature sensor 1 is inputted to a differential amplifier 3, which controls the set temperature outputted from the temperature setting circuit 2. A deviation voltage ΔT is output according to the difference from the set voltage Vs corresponding to the voltage Vs. Comparator 4 for temperature control uses the above deviation voltage ΔT.
and the reference voltage input from the reference voltage generator 6
Vz and outputs a binary output of on and off to the relay drive circuit 5.

The control output A from this relay drive circuit 5 becomes the output for temperature control, so for example, by controlling a combustion device such as a gas burner in a boiler on and off using the control output A, the detected temperature can be adjusted. Control is performed to make the temperature equal to the set temperature.

7 is an alarm control circuit, which includes first and second comparators OPA, OPB, a resistance network 8 consisting of resistors R ₁ , R ₂ , R ₃ , R ₄ , and Rv, a memory circuit 9, and a logic element.
Logic circuit 10 consisting of T ₁ , T ₂ , T ₃ , T ₄ , T ₅ etc.
, a first changeover switch group 11 consisting of switches S ₁ , S ₂ , S ₃ , S ₄ , S ₅ and a second changeover switch group 12 consisting of switches S ₆ , S ₇ , S ₈ . ing.

That is, the first changeover switch group 11 consisting of switches S ₁ , S ₂ , S ₃ , S ₄ , and S ₅ is connected to the output line of the reference voltage generator 6 and the voltage supply circuit L that supplies a predetermined voltage +V. They are connected to earth E, and are separately arranged to enable selection of various alarm operation modes, which will be described later.

Further, R ₁ , R ₂ , R ₃ configuring the resistor network 8 are the first changeover switch group S ₁ , S ₂ , S ₃ , S ₄ , S _{5 .}
The resistor _R4 is inserted and connected between the voltage supply circuit L and the switch _S3 , and the first changeover switch group _S1 , _S2 , _S3 , _S4 , S By switching and selecting ₅ , the combination of each resistor R ₁ , R ₂ , R ₃ , and R ₄ is changed, thereby generating alarm operating point voltages Vf and Vg for various alarm operating modes. Operating point voltage Vf, Vg is variable resistance
It is configured to be variable depending on RV.

Furthermore, the deviation voltage ΔT output from the differential amplifier 3 is applied to the first and second comparators OPA and OPB.
The alarm operating point voltages Vf, Vg generated by the resistor network 8 are inverted input, and these deviation voltages ΔT are compared with the alarm operating point voltages Vf, Vg to turn on,
It generates off-binarized outputs a and b.

Further, the second comparator OPB includes a memory circuit 9.
is connected, and this memory circuit 9 also serves as a comparator.
It inputs and stores OPB output b,
When the switch _S6 is on, the memory function stops, and the output e of the memory circuit 9 simply outputs a high level "H" regardless of the above output b, and when the switch _S6 is off, the above output is in the initial state. When b is at the low level "L", the output e is "L", and when the above output b becomes "H", this output b is stored and the output e is "H".
Even if this state continues and the output b becomes "L" again, the output e remains "H".

Further, a logic circuit 10 is connected to the pair of comparators OPA, OPB and the memory circuit 9, and this logic circuit 10 is connected to the pair of comparators OPA, OPB and the memory circuit 9.
The logic circuit 10 performs a logical operation on the binary outputs a and b from the memory circuit 9 and the binary output e from the storage circuit 9, and the logic circuit 10 performs a logical operation on the binary outputs g and h from the logic elements T ₄ and T ₅ . This is what is output.

Further, on the output side of the logic circuit 10, a second changeover switch group 12, S ₇ is provided for selecting and switching an appropriate one of the binary signals g and h output from the logic circuit 10. , S ₈ is connected,
An alarm driving circuit 13 is connected to the output side of the switching switch group 12, and the alarm driving circuit 13 is driven by receiving the output from the logic circuit 10, and the switching switches S ₇ and S ₈ receive the output of the signal g or h output from the logic circuit 10. The output of either one is sent to the transistor _T6 constituting the drive circuit 13 to perform alarm control and activate Ry.

Then, when the outputs g and h are "H", the alarm control relay Ry is turned on, activating the alarm device and notifying an abnormality in the temperature control system.

The alarm control circuit 7 configured as described above has six types of alarm operation modes, which will be described later.

The first mode is the set temperature as shown in Figure 3A.
The second mode is the alarm operating point temperature Tp set on the high temperature side with respect to Ts, the second mode is the alarm operating point temperature Tp is set on the low temperature side with respect to the set temperature Ts, as shown in Figure 3B, and the third mode is is the third mode in the second mode above.
The standby sequence function shown in Figure C is added, and this standby sequence function is performed when the detected temperature Tt
Even if the temperature is below the operating point temperature Tp during the initial temperature rise process, the alarm device will not activate, and once the set temperature
After reaching Ts, the alarm device is activated only when the temperature drops below the operating point temperature Tp again. The fourth mode has two operating point temperatures Tp on the high temperature side and low temperature side with respect to the set temperature Ts as shown in Figure 3D.
The fifth mode is the fourth mode with the above standby sequence function added to the low temperature side, and the sixth mode is the high temperature side and low temperature side with respect to the set temperature Ts as shown in Figure 3E. Two operating point temperatures Tp and Tp' are set, and the alarm device is activated in a range between these two operating point temperatures. Here, the set temperature Ts is the first
In the circuit shown in the figure, a voltage corresponding to the sum of the set voltage Vs and the reference voltage Vz (usually Vz = 0) and the difference between the set temperature Ts and the operating point temperature Tp (Tp') is generated by the variable resistor Rv. It is now possible to set it arbitrarily.

The above six types of alarm operation modes can be selected by the first and second changeover switch groups, and as shown in Figure 2, the on/off combinations of the switches making up these changeover switch groups Therefore, the operation mode can be switched.

That is, in the case of the first mode, switches S ₁ , S ₂ , S ₆ , and S ₈ in FIG. 1 are turned on, and all others are turned off. At this time, the first comparator OPA
The input Vf applied to the inverting input terminal at is resistor R ₄
Since it is connected to the power supply voltage +V via
Vf, and the output a of the comparator DPA is always "L".

On the other hand, a resistor _R1 is connected to the inverting input terminal of the comparator OPB.
and Rv, an operating point voltage Vg higher than the reference voltage Vz is input, and when the deviation voltage ΔT applied to the non-inverting input terminal exceeds Vg, the output b of the comparator OPB becomes "H".

The respective outputs a and b are input to inverters T ₁ and T ₂ of the logic circuit 10, respectively. At this time, the output at each point in the figure is always a=“L”, so c=
“H” Also, switch S ₆ is on, so it is always e
= “H”, and in this state, when (detection temperature Tt) < (operating point temperature Tp), that is, Vg >ΔT; b = “L”, d = “H”, f = “L”, g = “H”,
h
= “L”, relay Ry = off When Tp≦TtVg≦ΔT; b=≦“H”, d=“L”, f=“H”, g=“L”
,
h=“H”, relay Ry=on. Therefore, the alarm device is activated only when the detected temperature Tt becomes higher than the set temperature Ts and becomes equal to or higher than the operating point temperature Tp.

In the case of the second mode, switches S ₂ , S ₄ , S ₆ , S ₇
is on and all others are off. At this time, as in the case of the first mode, the output a of the first comparator OPA is always "L". Also a second comparator
A variable resistor Rv and a resistor _R2 are connected to the inverting input terminal of OPB.
This reference voltage Vz is divided by
An operating point voltage Vg lower than Vz is input, and as in the case of the first mode, when the deviation voltage ΔT applied to the non-inverting input terminal exceeds Vg, the output b becomes "H".
The respective outputs in this second mode are as follows.

Always a = "L", c = "H", e = "H", and when Tp < Tt, that is, Vg <ΔT; b = "H", d = "L", f = "L", g=“L”,
Ry=off When Tt≦Tp, that is, Vg≧ΔT; b=“L”, d=“H”, f=“L”, g=“H”,
Ry=on, and the alarm device is activated only when the detected temperature Tt becomes lower than the set temperature Ts and becomes below the operating point temperature Tp.

In the case of the third mode, since a standby sequence function is added to the second mode, the switch _S6 is turned off and the memory circuit 9 is made to function. That is, switches S ₂ , S ₄ , and S ₇ are turned on, and all others are turned off.

At this time, as in the case of the second mode, the deviation voltage ΔT applied to the non-inverting input terminal of the second comparator OPB
When exceeds the operating point voltage Vg input to the inverting input terminal, the output d of the comparator OPB becomes "H",
This output b is stored in the storage circuit 9. So,
Always a = “L”, c = “H”, and in the initial temperature rise process, when Tt < Tp, that is, VgΔT; b = “L”, d = “H”, e = “L”, f = “H”,
g
= “L”, Ry = off When Tp < Tt, that is, Vg <ΔT; b = “H”, d = “L”, e = “H”, f = “H”,
g
= “L”, Ry = off, and from the second time Tt≦Tp, that is, Vg≧
When ΔT; b = “L”, d = “H”, e = “H”, f = “L”,
g
= "H", Ry = on, and the alarm device is activated when the detected temperature Tt once exceeds the operating point temperature Tp and becomes below the operating point temperature Tp again.

In the case of the fourth mode, switches S ₃ , S ₅ , S ₆ , S ₇
is on and all others are off. At this time, the operating point voltage Vf of the first and second comparators OPA and OPB,
A voltage obtained by dividing the positive voltage V by resistors R ₄ , Rv, and R ₃ is applied to Vg. When the variable resistor Rv = 0 ohm, the operating point voltages Vf and Vg are equal to the reference voltage Vz, and the resistor When Rv is changed, the operating point voltage Vf,
If Vg is set to vary, the operating point temperatures Tp and Tp' can be set at equal intervals above and below the set temperature Ts. The output of each point at this time is, when Tt<Tp, that is, Vf>ΔT, Vg>ΔT
and; a=“L”, c=“H”, b=“L”, d=“H”,
e
= “H”, f = “L”, g = “H”, Ry = ON When Tp<Tt<Tp′, Vf>ΔT, Vg<ΔT; a=“L”, c=“H” , b=“H”, d=“L”,
e
= "H", f = "H", g = "L", Ry = off When Tp'< Tt, Vf < ΔT, Vg <ΔT; a = "H", c = "L", b = “H”, d = “L”,
e
= "H", f = "H", g = "H", Ry = ON, and the alarm device is activated when the detected temperature Tt is below the low temperature side operating point temperature Tp and above the high temperature side operating point temperature Tp' I will do it.

In the case of the fifth mode, the above-mentioned standby sequence function is added to the low temperature side of the above-mentioned fourth mode, and the output at each point is When Tt<Tp, the output is the same as in the third mode.

Since the operation in the fourth mode is reversed in the case of the fourth mode, the switch _S7 is turned off and the switch _S8 is turned on to obtain an inverted output h of the output g in the fourth mode. As a result, the relay Ry is turned on when the detected temperature Tt is in the range of Tp<Tt<Tp'.

In the above embodiment, a case has been described in which there are six types of alarm operation modes, but it goes without saying that the alarm operation modes may include only the first and second modes.

<<Effects of the Invention>> As explained above, in the temperature controller according to the present invention, the alarm control circuit has a plurality of alarm operation modes, and these alarm operation modes are set by a combination of changeover switches. Since the alarm operation mode can be selected according to the use, the alarm operation mode can be arbitrarily selected with one temperature controller depending on the purpose, and specifications can be changed. In addition, this eliminates the need to separately manufacture devices with different alarm operation modes, reducing the man-hours required to manufacture the devices, and also reduces the need for device users to be confused about model selection depending on the alarm operation mode. It has advantages such as eliminating

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing an embodiment of the temperature controller according to the present invention, Fig. 2 is a diagram showing the relationship between each alarm operation mode and the changeover switch group in this embodiment, and Figs. 3A to 3E. FIG. 2 is an explanatory diagram showing operating points of each alarm operating mode in this embodiment. 7... Alarm control circuit, OPA, OPB... 1st,
Second comparator, 8...Resistance network, 9...Storage circuit, 10...Logic circuit, 11...First changeover switch group, 12...Second changeover switch group, 13...
...Alarm drive circuit.

Claims (1)

[Scope of Claims] 1. A differential amplifier that outputs a deviation voltage according to the difference between a temperature detection voltage detected by a temperature sensor and a set voltage corresponding to a set temperature output from a temperature setting circuit; is connected to the output side of the
Comparing the deviation voltage output from this differential amplifier and the reference voltage output from the reference voltage generator,
A temperature controller equipped with a comparator that supplies a binary output of on and off to a relay drive circuit, and connected between the output side line of the reference voltage generator, the voltage supply circuit that supplies a predetermined voltage, and the ground. , the first alarm operating point voltage on the high temperature side is determined by the combination of resistors inserted through the first changeover switch group, which is turned on and off according to the alarm operating mode selected from a plurality of alarm operating modes. and the second on the low temperature side
a resistor network that generates an alarm operating point voltage; and a first resistor network that compares the deviation voltage output from the differential amplifier with the first and second alarm operating point voltages.
and a second comparator; connected to the first and second comparators, when the deviation voltage is equal to or higher than the first alarm operating point voltage;
Alternatively, when the voltage is below the second alarm operating point voltage, an alarm signal is output to the first output terminal, and when the deviation voltage is above the second alarm operating point voltage, the alarm signal is output to the first output terminal.
a logic circuit that outputs an alarm signal to a second output terminal when the voltage is below the alarm operating point of the logic circuit;
and a second changeover switch group for selecting and switching one of the second output terminals, and an alarm signal from the first or second output terminal of the logic circuit selected by the second changeover switch group. and an alarm drive circuit that drives the alarm element in response to the above-mentioned changeover switch group, and allows switching and selection of multiple types of alarm operation modes by a combination of on and off of the first changeover switch group and the second changeover switch group. A temperature controller characterized by: