JPH08273507A - Timer device - Google Patents

Abstract

PURPOSE: To provide an OFF-delay timer device enabling the operation of an OFF-delay timer by using an ON-delay timer in the OFF-delay timer device. CONSTITUTION: In an OFF-delay timer device reaching an OFF-condition after a fixed time from the change of an input condition, an ON-delay timer circuit T' and a condition retaining circuit for retaining a condition at the time of operation start are included, and then output equivalent to the output of an OFF-delay timer can be obtained based on the output of the ON-delay timer circuit T' and the condition retaining circuit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timer device, and more particularly to an off-delay timer device.

[0002]

2. Description of the Related Art Generally, a timer circuit is used in electric equipment for various time controls. The timer circuit includes an on-delay timer circuit and an off-delay timer circuit. The on-delay timer circuit changes the signal state by time-up after a set time has elapsed since a certain event occurred. On the other hand, the off-delay timer circuit maintains its state for a set time when a certain event occurs, and then changes the signal state.

[0003]

In an apparatus using a CPU (microcomputer), the on-delay timer and the off-delay timer are built in the CPU, so that both delay timers can be easily used.

However, in a device that does not use a CPU (microcomputer), only an on-delay timer is built in as a timer circuit, so that the off-delay timer cannot be operated. If a mechanical off-delay timer is used to operate the off-delay timer, the cost and the number of parts will increase.

If the output of the on-delay timer is inverted and the operation of the off-delay timer is to be performed, the operation of the off-delay timer cannot be obtained at the start of operation. That is, at the start of operation, even if the timer coil of the on-delay timer is excited, there is a region where the timer contact does not change due to the delay within the set time of the timer. I can't make it work.

Therefore, an object of the present invention is to provide an off-delay timer device capable of operating the off-delay timer by using the on-delay timer.

[0007]

SUMMARY OF THE INVENTION The present invention detects a signal when a timer coil of an on-delay timer is de-energized at the time of starting operation, and masks a delay at power-on, thereby turning on. The delay timer can be used to perform the same operation as the off-delay timer.

That is, according to the first aspect of the present invention, in an off-delay timer device which is turned off after a fixed time from a change in the input state, an on-delay timer circuit and a state holding circuit for holding a state at the start of operation. , And is configured to obtain an output equivalent to that of the off-delay timer, based on the outputs of the on-delay timer circuit and the state holding circuit.

According to a second aspect of the present invention, in an off-delay timer device that is turned off after a fixed time has elapsed after a change in the input state, an on-delay timer circuit and a relay circuit that holds the on-state at the start of operation are provided. By including the AND logic of the logical negation output of the on-delay timer circuit and the logical negation output of the relay circuit, the output is equivalent to that of the off-delay timer.

[0010]

According to the first aspect of the present invention, the output of the on-delay timer circuit is masked with the output of the state-holding circuit, including the on-delay timer circuit and the state-holding circuit for holding the state at the start of operation. , And an output equivalent to that of an off-delay timer is obtained.

According to the second aspect of the present invention, an ON-delay timer circuit and a relay circuit for holding an ON state at the start of operation are included, and a logical NOT output of the ON-delay timer circuit is set to a logical NOT of the relay circuit. The output is masked to obtain the same output as the off-delay timer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described with reference to the drawings.

First, FIG. 1A shows a restart prevention circuit for a compressor using an off-delay timer. FIG.
As shown in (A), various switches, a relay coil, and relay contacts interlocking with them are connected between the DC power supply bus P and N to form a necessary sequence circuit.

The circuit operation of FIG. 1A will be described below with reference to the timing chart of FIG.

When the operation switch S1 is turned on, the coil R1 is excited and the contacts R1 'and R1' are turned on. As a result, the compressor 52c is turned on and the coil of the off-delay timer T3 'is excited, so that the contact T3 is opened.

Even when the compressor 52C is turned off, the contact T3 'remains open during the time T, so that the contact T2' is not turned on, that is, the compressor 52C is not restarted.

The 2-second delay of the compressor 52C shown in FIG. 1B is obtained by the coil T2 'to prevent the compressor 52C from turning on simultaneously with the compressor 52F.

As described above, the off-delay timer T3 '
Thus, the open state of the contact T3 'is maintained for the time T, but in the embodiment of the present invention, the above-mentioned operation is achieved by using the on-delay timer.

FIG. 2A shows a restart prevention circuit for a compressor using an on-delay timer according to an embodiment of the present invention. As shown in FIG. 2 (A), the DC power supply bus P-
As shown in the drawing, various switches, relay coils, and relay contacts interlocking with them are connected between N to form a necessary sequence circuit. In FIG. 2 (A), a portion surrounded by a chain line is shown. 100 and 200 are shown in FIG.
The difference from the circuit of (A) is shown.

The operation of the circuit of FIG. 2A will be described below with reference to the timing chart of FIG. In addition,
Before start of operation, when power is turned on, on-delay timer T '
The contact turns into the ON state after the arbitrary set time has elapsed and cannot be operated during this set time.

Based on the waveform of the coil of the on-delay timer T ′, the waveform of the T ″ contact having the delay time T can be obtained. The waveform of this T ″ contact is shown as T3 ′ in FIG.
Compared with the contact waveform, the T ″ contact waveform portion 30
Except for 0 (the shaded area), the two are considered to match.

That is, during the delay time T immediately after the start of operation, the T ″ contact is open (see FIG. 2B),
On the other hand, when the off-delay timer is used,
Since it is in the closed state (see FIG. 1B), it is understood that the waveform of the T ″ contact needs to be masked in the region of the delay time T immediately after the start of operation.

As the masking signal, the signal of the relay R40 which is closed when the compressor 52C is first turned on (at the time of startup) and holds the closed state thereafter (see FIG. 2B) is used.

From the above, the on-delay timer T '
It can be seen that, in order to perform the operation of the off-delay timer by using the AND logic, the waveform of the T ″ contact of the on-delay timer T ′ may be ANDed with the waveform obtained by logically negating the waveform of the relay R40. The AND logic waveform thus obtained coincides with the waveform of the T3 contact shown in FIG.

[0025]

As described above, according to the invention described in claims 1 and 2, it is possible to operate the off-delay timer by using the on-delay timer.
Compared with the case of using a mechanical off-delay timer,
The cost reduction and the number of parts can be reduced.

[Brief description of drawings]

FIG. 1 is a restart prevention circuit for a compressor using an off-delay timer and an operation explanatory diagram.

FIG. 2 is a restart prevention circuit for a compressor using an off-delay timer according to an embodiment of the present invention, and an operation explanatory diagram.

[Explanation of symbols]

 T'on-delay timer R40 relay 52C compressor

Claims (2)

[Claims] 1. An off-delay timer device, which is turned off after a fixed time from a change in an input state, includes an on-delay timer circuit and a state holding circuit for holding a state at the start of operation. And an off-delay timer device that obtains an output equivalent to that of an off-delay timer based on the output of the state holding circuit. 2. An off-delay timer device which is turned off after a lapse of a certain time from a change in an input state, including an on-delay timer circuit and a relay circuit which holds an on-state at the start of operation. An off-delay timer device characterized in that an output equivalent to that of an off-delay timer is obtained by taking an AND logic of the logical negation output of the above and the logical negation output of a relay circuit.