JP2000045808A - Emergency stopping circuit for machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an emergency stop of a machine in an operator cab or even outside the operator cab, in the machine capable of being driven either by an electric motor or an engine by enabling the electric motor and the engine to be stopped by one switch. SOLUTION: A normally open contact 27 for an emergency stopping relay R5 is provided between an AC power supply 11 and a start-stop circuit 33 for an electric motor driven by the AC power supply 11. A normally open contact 38 for the emergency stopping relay R5 is provided between a battery 41 and start-stop circuits 44, 54 for an engine driven by the battery 41. A coil 20 for the emergency stopping relay R5, which is closed by energizing the normally open contacts 27, 38, is provided and plural normally closed circuit type emergency stopping switches 58a, 58b, 58c are connected in series with the coil 20. These emergency stopping switches 58a, 58b, 58c are respectively installed to an operable position in an operator cab, and to an operable position outside the machine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emergency stop circuit applied to a machine that can be driven by either an electric motor or an engine.

[0002]

2. Description of the Related Art Conventionally, in a construction machine which can be driven by either an electric motor or an engine, the following method is generally used for urgently stopping the operation of the machine.

[0003] One method is to stop the operation of a machine by a start / stop switch installed in a cab without installing an emergency stop switch.

In another method, an emergency stop switch dedicated to driving an electric motor is installed in a cab, and a start / stop switch dedicated to driving an engine is separately installed. Is a method of individually stopping with a start / stop switch.

[0005]

SUMMARY OF THE INVENTION In such a case,
Since an emergency stop switch is installed only in the cab,
In some cases, the driver is inaudible due to noise or the like to stop the aircraft in an emergency, which is a factor leading to an accident.

In addition, since an emergency stop switch dedicated to driving the electric motor and a start / stop switch dedicated to driving the engine are separately provided for each drive, it is possible to accurately determine which stop switch to operate in an emergency. However, it is not easy to make such a determination instantly.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to stop an electric motor and an engine with a single switch in a machine that can be driven by both an electric motor and an engine. And It is another object of the present invention to enable the machine to be stopped urgently in or outside the cab.

[0008]

According to the first aspect of the present invention, there is provided an electric motor and an engine start / stop circuit for starting and stopping an electric motor and an engine, and a power supply, an electric motor and an engine start / stop circuit. The emergency stop relay normally open contact provided between the emergency stop relay, the emergency stop relay normally open contact closed by excitation, and the emergency stop relay coil connected in series with the emergency stop relay coil 3 is an emergency stop circuit of a machine including a closed emergency stop switch.

With this, in a machine that can be driven by either the electric motor or the engine, only by operating one emergency stop switch, the excitation of the coil of the emergency stop relay is released and the start of the electric motor and the engine is started. The normally open contact of the emergency stop relay provided for the stop circuit can be opened, so that they can be stopped urgently even when driven by an electric motor or when driven by an engine.

According to a second aspect of the present invention, there is provided an electric motor start / stop circuit driven by an AC power supply to start or stop an electric motor, a DC power supply, and an engine driven by the DC power supply to start or stop an engine. A normally open contact of an emergency stop relay provided between an engine start / stop circuit, an AC power supply and an electric motor start / stop circuit, and between a DC power supply and an engine start / stop circuit, respectively. Emergency stop circuit for a machine comprising an emergency stop relay coil that closes the normally open contact of the emergency stop relay by excitation, and a normally closed emergency stop switch connected in series to the emergency stop relay coil It is.

Thus, in a machine that can be driven by either the electric motor or the engine, by operating one emergency stop switch, the excitation of the coil of the emergency stop relay is released and each start of the electric motor and the engine is started. -The normally open contacts of the emergency stop relays provided for the stop circuits are opened, so that they can be stopped urgently even when driven by an electric motor or when driven by an engine.

According to a third aspect of the present invention, in the emergency stop circuit for a machine according to the first or second aspect, a plurality of emergency stop switches are connected in series, and these emergency stop switches are connected to the cab of the machine. And a position operable outside the machine.

Thus, the machine can be urgently stopped not only from the cab but also from outside the machine by the emergency stop switch installed not only in the cab but also outside the machine.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to one embodiment shown in FIGS. 1 to 4 and another embodiment shown in FIG.

The circuit shown in FIG. 1 corresponds to a construction machine driven mainly by an electric motor but can also be driven by an engine if necessary. The electric motor is driven by an AC circuit, and the engine is Driven by a circuit.

An AC power supply 11 is connected to an AC circuit 13 for an electric motor via a circuit breaker (NFB) 12, and is further connected to an AC / DC converter 14 for converting AC into DC. Circuit 15 is connected.

The DC circuit 15 includes a coil 16 of the relay R1,
Relay R2 coil 17, Relay R3 coil 18, Relay R4 coil 19, Emergency stop relay R5 coil 20 and relay
It has a coil 21 of R9.

On the other hand, the AC circuit 13 is
The normally closed contact 22 of the relay R2 (hereinafter, the normally closed contact is referred to as “normally closed contact”) 22 is connected to the coil 23 of the relay R6, and the normally open contact of the relay R3 (hereinafter, normally closed contact is referred to as “normally closed contact”). 24) and normally closed contact 25 of relay R9
The coil 26 of the relay R7 is connected, and the normally open contact 27 of the emergency stop relay R5, the normally open contact 28 of the relay R1,
The normally open contact 29 of the relay R3 and the coil 30 of the relay R8 are connected.

Further, a relay is connected to the normally open contact 28 of the relay R1.
Normally open contacts 31 for self-holding of R8 are connected in parallel,
Normally open contact 27 of emergency stop relay R5 and normally open contact of relay R1
The circuit drawn from between the relay 28 and the normally open contact 32 of relay R8
, An electric motor start / stop circuit 33 for starting or stopping the electric motor for driving the construction machine is connected.

In the DC circuit 15, electric components are connected to the AC / DC converter 14 via a normally open contact 34 of a relay R7.
35 is connected, and via a diode 36, a normally open contact 37 of the relay R6 and a normally open contact 38 of the emergency stop relay R5,
The start / stop switch 39 is connected.

A battery 41 as a DC power supply and a charging alternator 42 are connected between the normally open contact 37 of the relay R6 and the normally open contact 38 of the emergency stop relay R5.

The alternator 42 is mounted on the engine,
Although it is an AC generator driven by an engine, it is a charging generator that has a built-in rectifier for converting AC to DC and outputs a DC output to the battery 41.

Here, a series of circuits extending from the alternator 42 to the + side of the battery 41 is an engine-driving charging circuit 61 for charging the battery 41 with DC power supplied from the alternator 42 driven by the engine when the engine is driven.
Is formed.

On the other hand, from the AC / DC converter 14 through the diode 36 and the normally open contact 37 of the relay R6, the +
A series of circuits reaching the side form an electric motor driving charging circuit 62 that converts the AC power of the electric motor into a DC power when the electric motor is driven and charges the battery 41.

Further, the normally open contact 34 of the relay R7 and the relay R7
The normally open contact 37 of R6 is an interlock circuit that supplies the voltage generated by the alternator 42 to the battery 41, the electric component 35, and the DC circuit 15 without applying the voltage generated by the alternator 42 to the diode 36 or the AC / DC converter 14. 63 are formed.

On the positive side of the battery 41, the normally open contact 43 of the relay R2, the normally closed contact 44 of the relay R7, and the coil 21 of the relay R9
And are connected. Further, a normally open contact 45 of the relay R9 is provided between the electric component 35 and the normally open contact 34 of the relay R7.

The start / stop switch 39 is a common key switch capable of starting or stopping each drive of the electric motor and the engine, and is a two-pole rotary switch having an OFF terminal C, a start terminal S, and an ACC terminal R. It is also a key switch.

A start terminal S of the start / stop switch 39 includes a hydraulic lock switch 46 for fixing a hydraulic actuator such as a construction machine on a hydraulic circuit, a normally closed contact 47 of a relay R2, and a coil 16 of a relay R1. Further, an engine start circuit 49 is connected to a circuit drawn from between the hydraulic lock switch 46 and the normally closed contact 47 of the relay R2 via a normally open contact 48 of the relay R2.

On the other hand, the normally open contact 51 of the relay R4, the normally closed contact 52 of the relay R8, and the coil 17 of the relay R2 are connected to the ACC terminal R of the start / stop switch 39. The normally open contact 53 for self-holding of the relay R2 is connected in parallel to the normally open contact 51 of the relay R2, and the normally closed contact of the relay R8 is connected.
In the circuit drawn from between 52 and coil 17 of relay R2,
The engine stop circuit 54 is connected.

Further, the normally closed contact 55 of the relay R2 and the coil 18 of the relay R3 are connected to the ACC terminal R of the start / stop switch 39, and a normal switch for switching between an AC power supply and a DC power supply. Power switch 56, an open manual contact
And the coil 19 of the relay R4 are connected.

A circuit 57 drawn out from between the normally open contact 37 of the relay R6 and the normally open contact 38 of the emergency stop relay R5.
In addition, a plurality of emergency stop switches 58a, 58b, 58c which are normally closed type manual contacts, and a coil 20 of an emergency stop relay R5.
And are connected in series.

A plurality of emergency stop switches 58a, 58b, 58c
Are connected in series, of which at least one emergency stop switch 58a is connected to the cab (cab)
Installed in a location accessible to the operator and operable within the vehicle, and at least one emergency stop switch 58c
Is installed outside the operator's cab at a construction machine position that can be easily operated by, for example, a worker on the ground.

Therefore, both when the electric motor is driven and when the engine is driven, the driving thereof can be stopped urgently in the cab or outside the cab.

As described above, on the load side of the start / stop switch 39, the common start / stop circuit for starting or stopping both the electric motor and the engine is arranged. In addition, a plurality of emergency stop switches 58a, 58b, 58c that can be operated outside the cab
Is arranged.

Next, the operation (A) of the illustrated embodiment will be described.
(B) and (C) will be described.

(A) First, a method for charging the battery 41 at each drive, regardless of whether the construction machine is driven by an electric motor or an engine, will be described.

When the electric motor is driven or when the circuit breaker 12 is in the on state without driving the electric motor, the relay
Since the coil 23 of R6 is excited, the normally open contact 37 of the relay R6 is closed, the coil 20 of the emergency stop relay R5 is excited, and the normally open contact 38 of the emergency stop relay R5 is closed. DC voltage converted from AC to DC (about 27
V) is applied to the battery 41 and the start / stop switch 39.

Therefore, if the voltage of the battery 41 is lower than the DC voltage (about 27 V) after the AC / DC conversion,
The battery 41 is charged by the potential difference.

On the other hand, when the engine is driven, when the power switch 56 is pressed, the coil 19 of the relay R4 is excited,
The normally open contact 51 of R4 closes, the coil 17 of the relay R2 is excited, the self-holding action of the normally open contact 53 of the relay R2 works, and the normally open contact 43 of the relay R2 closes to the coil 21 of the relay R9.
Is excited, and the normally open contact 45 of the relay R9 is closed.

At this time, the normally closed contact 22 of the relay R2 is opened, so that the coil 23 of the relay R6 is de-energized.
Since the normally closed contact 55 of R2 is opened, the coil 18 of the relay R3 is also de-energized, the normally open contact 24 of the relay R3 is opened, and the coil 26 of the relay R7 is de-energized.
Opens.

That is, when the engine is driven, the relay R4,
R2 and R9 are in the excitation state (hereinafter, this excitation state is referred to as “ON state”).
), And the relays R6, R3, and R7 are in the de-energized state (hereinafter, this de-energized state is referred to as the "off state"), so that an interlock circuit is formed, and the generated voltage from the alternator 42 The voltage is not applied to the converter 14, but is supplied to the battery 41 and charged.

As described above, in a construction machine that can be driven by either the electric motor or the engine, the battery 41 can be charged both when the electric motor is driven and when the engine is driven.

(B) Next, with reference to FIGS. 2 to 4, the operation of the start / stop circuit that can start and stop each drive of the electric motor and the engine by the common start / stop switch 39 will be described. . In FIGS. 2 to 4, the excited state (ON state) of each relay R1, R2, R3, R4, R5, R6, R7, R8, and R9 is shown by a black circle, and the excited release state (OFF state) is a white circle. Indicated by

First, regardless of whether the electric motor or the engine is driven, the hydraulic operation of the construction machine is fixed by closing the hydraulic lock switch 46.

FIG. 2 shows a case where the electric motor drives a construction machine with the electric motor.

(I) The AC power supply 11 is converted into a DC power supply by the AC / DC converter 14 and supplied to the start / stop switch 39.

As described above, the relays R6 and R5 are on, and when the start / stop switch 39 is switched to the ACC position, the relays R3 and R7 are turned on and the electric components 35 are connected.

(Ii) When the start / stop switch 39 is switched to the start position, the relays R1 and R8 are turned on, power is supplied to the electric motor start / stop circuit 33, and the electric motor starts.

(Iii) When the start / stop switch 39 is switched to the off position, the relays R3 and R8 are turned off, and the electric motor stops.

FIG. 3 shows a case where the engine is driven and the AC power supply 11 is connected.

(I) The AC power supply 11 is converted into a DC power supply by the AC / DC converter 14, and the DC power is supplied to the start / stop switch 39 via the relays R6 and R5 in the ON state. When 39 is set to the ACC position, the relays R3 and R7 are turned on.

(Ii) When the power switch 56 is pressed to drive the engine, the relays R4 and R2 are turned on,
Relays R3, R6, and R7 are turned off, and power is
At the same time, the relay R9 is turned on, and the electric component 35 is connected to the battery 41.

(Iii) When the start / stop switch 39 is switched to the start position, DC power is supplied from the battery 41 to the engine start circuit 49, and the engine is started. When the start / stop switch 39 is switched to an off position (not shown), the power to the engine stop circuit 54 is turned off, and the engine stops.

FIG. 4 shows a case where the engine is driven and no AC power is applied.

(I) The emergency stop switch 58a is connected to the battery 41.
DC power is supplied from the battery 41 to the start / stop switch 39 according to the on state of the emergency stop relay R5 connected via the switches 58b, 58b and 58c. When the start / stop switch 39 is set to the ACC position, the relay R3 is turned on.

(Ii) When the power switch 56 is pressed to drive the engine, the relays R4 and R2 are turned on,
Relay R3 is turned off, and relay R9 is turned on.

(Iii) When the start / stop switch 39 is switched to the start position, DC power is supplied from the battery 41 to the engine start circuit 49, and the engine starts. When the start / stop switch 39 is switched to an off position (not shown), the power to the engine stop circuit 54 is turned off, and the engine stops.

As described above, only when the engine is driven, the start-up wait state is set by the power supply switch 56. However, the electric motor drive and the engine drive can be started or stopped by the start / stop switch 39 which is a common key switch.

As shown in FIGS. 1 to 4, a hydraulic lock switch 46 is provided at the start position of the start / stop switch 39. Therefore, when the hydraulic lock switch 46 is in the unlocked state in which the hydraulic lock switch 46 is opened. Since the relay R1 is off and the relay R8 cannot be excited at first, power is not supplied to the electric motor start / stop circuit 33, and power is not supplied to the engine start circuit 49, so that the electric motor and the engine are not supplied. Both drives cannot be started.

(C) Next, the operation of urgently stopping the driving of the electric motor and the engine during driving will be described.

When the electric motor is driven, the AC power supply 11
The DC converter 14 converts the DC power into DC power, and supplies the DC power to a start / stop switch 39. When the engine is driven, the DC power is supplied from a battery 41 to the start / stop switch 39. At this time, DC power is always supplied to the plurality of emergency stop switches 58a, 58b, 58c connected in series.

In an emergency, the emergency stop switch 58a on the power supply side of the start / stop switch 39 or outside the cab
, 58b, and 58c, the coil 20 of the emergency stop relay R5 is de-energized, so that the normally open contact 27 of the emergency stop relay R5 of the AC circuit 13 and the emergency stop relay of the DC circuit 15 The normally open contact 38 of R5 opens together, shutting off the power to the electric motor start / stop circuit 33, and also shutting off the power to the start / stop switch 39 at the same time, regardless of whether the electric motor or the engine is driven. It can be stopped and the operation of the machine can be stopped.

Next, FIG. 5 shows another embodiment of the present invention, in which the electric motor is driven by a DC power supply as in the case of the engine. The same parts as those of the circuit shown in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

An electric motor / engine start / stop circuit 59 is provided on the load side of the start / stop switch 39, and a plurality of emergency stop switches 58a, 58b, 58c are connected in series on the power supply side of the start / stop switch 39. Is provided.

These emergency stop switches 58a, 58b, 58
At least one emergency stop switch 58a of c
The at least one emergency stop switch 58c is installed inside the cab, and is installed outside the cab.

When the electric motor is driven, the AC power supply 11
The DC power is converted into a DC power by the DC converter 14, and the DC power is supplied to the start / stop switch 39. The start / stop switch 39 supplies the DC power to the start / stop circuit 59. At this time, the emergency stop switches 58a, 58b, 58c also
DC power is always supplied from the AC / DC converter 14.

When the engine is driven, the power supply switch 56 is closed to excite the coil 19 of the relay R4, thereby opening the normally closed contact 60 of the relay R4 and supplying DC power from the battery 41 to the start / stop switch 39. , This start / stop switch
DC power is supplied from 39 to the start / stop circuit 59. At this time, DC power is constantly supplied from the battery 41 to the plurality of emergency stop switches 58a, 58b, 58c.

In an emergency, the excitation of the coil 20 of the emergency stop relay R5 is released by pressing one of a plurality of emergency stop switches 58a, 58b, 58c arranged inside and outside the cab. Then, the normally open contact 38 of the emergency stop relay R5 opens, shuts off the power to the start / stop switch 39, and stops the operation of the machine.

Therefore, both when the electric motor is driven and when the engine is driven, the driving thereof can be stopped urgently in the cab or outside the cab.

As described above, a construction machine that can be driven by either the electric motor or the engine can be stopped by either the emergency stop switch installed inside the cab or the emergency stop switch installed outside the cab. .

[0071]

According to the first aspect of the present invention, only by operating one emergency stop switch, the excitation of the coil of the emergency stop relay is released, and the start / stop circuit for the electric motor and the engine is stopped. The normally open contact of the emergency stop relay provided can be opened, and even if the machine is driven by an electric motor or driven by an engine, they can be stopped urgently.

According to the second aspect of the present invention, in a machine having a start / stop circuit for an electric motor driven by an AC power supply and a start / stop circuit for an engine driven by a DC power supply, By operating the emergency stop switch, the excitation of the coil of the emergency stop relay is released, and the normally open contact of the emergency stop relay provided for each start / stop circuit of the electric motor and the engine is opened. Both when driven by an electric motor and when driven by an engine, they can be stopped urgently.

According to the third aspect of the present invention, a plurality of emergency stop switches are connected in series, and these emergency stop switches are operable in the machine cab and at positions operable outside the machine. The machine can be stopped urgently not only from the cab but also from outside the machine.

[Brief description of the drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of a relay circuit provided with a machine emergency stop circuit according to the present invention.

FIG. 2 is an electric circuit diagram showing an operation of the relay circuit when the electric motor is driven.

FIG. 3 is an electric circuit diagram showing an operation of the relay circuit when the engine is driven and an AC power supply is connected.

FIG. 4 is an electric circuit diagram showing an operation of the relay circuit when the engine is driven and no AC power is applied.

FIG. 5 is an electric circuit diagram showing another embodiment of the relay circuit provided with the emergency stop circuit of the machine according to the present invention.

[Explanation of symbols]

 11 AC power supply R5 Emergency stop relay 20 Coil 27, 38 Normally open contact (normally open contact) 33 Electric motor start / stop circuit 41 Battery 49, 54 as DC power supply Engine start / stop circuit 58a, 58b, 58c Emergency Stop switch

Continuation of the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) H02P 3/00 H02P 3/00 Z F term (reference) 2D015 GA03 GB02 3G065 BA06 CA00 DA04 EA06 JA12 JA14 JA16 3G092 AC02 AC06 DF05 DG09 FA45 FB07 HF19Z HF20Z 3G093 AA07 AA10 BA04 DA13 EB08 EC01 5H530 AA01 AA18 BB18 CC06 DD04 DD15 DD19 DD21

Claims (3)

[Claims] An electric motor and an engine start / stop circuit for starting and stopping an electric motor and an engine, and an emergency stop relay provided between a power supply and the electric motor and an engine start / stop circuit, a normally open circuit. A contact, a coil of the emergency stop relay that closes the normally open contact of the emergency stop relay by excitation, and a normally closed emergency stop switch connected in series to the coil of the emergency stop relay. Emergency stop circuit of the machine. 2. An electric motor start / stop circuit driven by an AC power supply to start or stop an electric motor; a DC power supply; an engine start / stop circuit driven by the DC power supply to start or stop the engine; The normally open contacts of the emergency stop relays provided between the AC power supply and the start / stop circuit of the electric motor and between the DC power supply and the start / stop circuit of the engine, and the normally open contacts of these emergency stop relays An emergency stop circuit for a machine, comprising: an emergency stop relay coil that closes a contact by excitation; and a normally closed emergency stop switch connected in series to the emergency stop relay coil. 3. A plurality of emergency stop switches are connected in series, and these emergency stop switches are respectively installed at a position operable in a machine cab and a position operable outside the machine. The emergency stop circuit for a machine according to claim 1 or 2, wherein: