JPH11158942A - Alarm device of working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide such an alarm device that an alarm is raised when a selective switch is set in a singular operation selective position in an operation circuit of a hydraulic actuator. SOLUTION: An interlocking switch 25 for making switching operation by interlocking with a selective switch is provided, the interlocking switch 25 is connected to an alarm 28 to form an electric circuit 23, and power to the electric circuit 23 is connected in the case of a singular operation selective position contact state of the selective switch. The selective switch is set in a key switch 24 operating by inserting a key, and the alarm 28 is so constituted that it issues an alarm sound or an alarm light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alarm device mounted on a working machine such as a construction machine.

[0002]

2. Description of the Related Art FIG. 7 is a boom float circuit diagram described in Japanese Patent Application Laid-Open No. 2-236318. FIG.
In the boom float circuit shown in FIG.
Operating circuits 20 and 21 for communicating the directional control valve 8
The solenoid valve 27 with a float oil passage position is provided between the solenoid valve 27 and the electric circuit 32 for switching the electromagnetic valve 27 with the float oil passage position.
0 and a manual operation automatic return contact type switch 33 (hereinafter, referred to as a return contact type switch 33) which is an operation switch are connected in series. When the manual contact switch 30 is turned off, the solenoid valve 27 with the float oil passage position is in the shutoff oil passage position. Therefore, even if the return contact switch 33 is turned on, the boom cylinder 5 is turned off.
Does not float. However, the manual contact switch 30 is kept on, and the return contact switch 3
When the switch 3 is turned on, the solenoid 28 is energized, and the solenoid valve 27 with the float oil passage position is switched from the shutoff oil passage position to the float oil passage position nu. Therefore, the boom cylinder 5 can be set in the floating state only when the return contact switch 33 is turned on. Therefore, for example, when compaction work or pile driving work using a bucket is performed, the manual contact switch 30 is turned on, and the boom direction switching valve 8 is further switched to the boom raising oil passage position. Raise the boom. When the bucket at the tip of the work attachment rises to a required height, the return contact switch 33 is turned on. Since the boom cylinder 5 replaces the float state,
The bucket can be dropped and lowered together with the boom.

[0003]

When a hydraulic excavator having a prior art boom float circuit shown in FIG. 7 performs a normal excavation operation, the manual contact type switch 30, which is a selection switch, is turned off in principle. When performing soil compaction work, pile driving work, or the like, the boom is operated with the manual contact switch 30 being turned on. However, even when the manual contact switch 30 is kept on when performing the normal excavation work, the boom cylinder 5 does not float as long as the return contact switch 33 is kept off. . For this reason, the user may not be aware that the manual contact switch 30 is kept on, and may be performing the normal excavation work. In this case, if the operator's finger inadvertently presses the return contact switch 33, which is an operation switch, the boom cylinder 5 will be in a floating state and may unexpectedly rotate downward. The present invention provides a selector switch for selecting an operation of a hydraulic actuator disposed on a work machine between a normal operation and a specific operation in accordance with a task, and a stop state or an execution state of the specific operation. It is an object of the present invention to provide an alarm device for a working machine, which issues an alarm when the selection switch is in a contact state of a specific operation selection position, in an operation circuit of a hydraulic actuator having an operation switch that can be switched to another. .

[0004]

According to the present invention, an operating circuit of at least one hydraulic cylinder of a work attachment mounted on a working machine can be switched between a normal operating oil passage position and a short circuit oil passage position. The float switching valve is provided, and the float switching valve is selectively switched by a selection switch, and at least one component of the work attachment is brought into a float state by operating the operation switch according to the work content. In the operation circuit described above, an interlocking switch is provided for switching operation in conjunction with the selection switch, an electric circuit is formed by connecting the interlocking switch and an alarm device, and a short-circuit state oil passage position of the float switching valve is provided. Sometimes the electrical circuit was energized. In the above case, the selection switch is set to a key switch operated by inserting a key, and the key of the key switch is inserted into a neutral position to bring the selection switch into a normal operation selection position contact state. The alarm generation of the alarm device is stopped, the key is turned to the rotating operation state, the selection switch is set to the special operation selection position contact state, the alarm is generated by the alarm device, and the key is set. By pulling out the neutral position, the selection switch is kept in the normal operation selection position contact state, and the alarm is disabled from generating an alarm.
The alarm device emits an alarm sound or an alarm light.

In the present invention, an interlocking switch is provided which operates in conjunction with the selection switch, and an electric circuit is formed by connecting the interlocking switch and an alarm. The selection switch is operated by inserting a key. Since the key switch is set, the key of the key switch is inserted into the neutral position so that the selection switch is brought into the normal operation selection position contact state and the alarm device is set to the stop state. it can. Then, by turning the key to the turning operation state, the selection switch can be set to the contact state of the specific operation selection position and the alarm can be set to the state of generating an alarm sound or an alarm light. Further, by pulling out the key from the neutral position, the selection switch can be held in the normal operation selection position contact state, and the alarm can be disabled from generating an alarm.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a working machine equipped with an alarm device according to the present invention (a base machine of a working machine is a hydraulic shovel), in which a compaction roller 2 is attached to the tip of a work attachment 1 to compact a backfilled soil surface in a deep groove. It is a side view showing the state where work is performed. In the drawing, reference numeral 3 denotes a lower traveling body of the working machine, 4 denotes an upper revolving superstructure connected to an upper portion of the lower traveling body 3, 6 denotes a boom of the work attachment 1, 7
Is an arm, 9 is a boom cylinder, 10 is an arm cylinder, and 11 is a bucket cylinder. FIG. 2 is an electric circuit diagram showing a hydraulic circuit and an alarm device of the work machine in FIG. In the figure, 12 and 13 are a bottom-side oil chamber and a rod-side oil chamber of the boom cylinder 9, respectively, 14 is a boom direction switching valve, 15 is a main pump, 16 is a pilot pump, 17 is a boom hydraulic remote control valve, and 18 is a boom hydraulic remote control valve. An oil tank, 19 is a float valve block which is a component of the float device for the boom cylinder 9, 21 and 22 are 3-position electromagnetic switching valves in the float valve block 19, 23 is an electric circuit, and 24 is a boom cylinder 9. A key switch, which is a selection switch operated to select one of a normal operation and a float state, 25 is an interlock switch that operates in conjunction with a key switch 24, and 26 is a switch that stops or executes the float state of the boom cylinder 9. An operation switch 28 that can be switched to a state is an alarm that issues an alarm.

In the working machine circuit shown in FIG. 2, an operating circuit (29-29 ', 31) communicating with the boom cylinder 9 is provided.
A float valve block 19 is provided in the float valve block 19, and the switching positions other than the neutral positions A and B of the three-position electromagnetic switching valves 21 and 22 in the float valve block 19 are for a short-circuit state. Oil passage positions C, D, E, F are set, and a pair of tank communication lines (line 34, 35, line 36, 37) respectively communicating with the oil tank 18 from the three-position switching valves 21, 22 are provided. ), Each of which is provided with a variable throttle section 38, 39, 40, 41, and one of the pair of tank communication pipes 35, 3
7 and in parallel with the variable throttle portions 39 and 41 provided in the oil tank 1
The check valve 42, 43 in the suction flow direction of the oil from the nozzle 8 is connected to the work attachment 1 (shown in FIG. 1) when the three-position switching valves 21, 22 are switched to the short-circuit state oil passage positions c, c, respectively. ), The speed at which the boom cylinder 9 extends or contracts in response to the operation of the arm cylinder 10 is made faster than when the other short-circuit state oil passage position D and E are switched. In the so-called regular mode R, the so-called strong mode S is when the short-circuit state oil passage position D and E are switched), and in any of the short-circuit state oil passage positions C, F, D, and E,
A part of the weight of the body (the upper revolving unit 4 and the lower traveling unit 3) is added to the work attachment 1.

FIG. 3 is a main part plan view showing the vicinity of the driver's seat 44 of the upper swing body 4 shown in FIG. In the figure, 45
_L and 45 _R are operation levers for left and right operations, respectively.
Are the operation switches attached to the operation lever 45 _L ,
6 is a switch box fixed diagonally forward of the driver's seat 44, 24 is a key switch as a selection switch disposed in the switch box 46, 47 is a key switch 2
4 is the key that has been entered. FIG. 4 is a view of the switch box 46 in FIG. FIG.
FIG. 4 is a diagram of the mounting state of the operation switch 26 in FIG. 3 as viewed from B. In the figure, 26 is an operation switch mounted fixed relative to the bracket 49 provided on the grip 48 below the operating lever 45 _L, 50 is a push button of the operation switch 26.

Next, the configuration of an alarm device according to an embodiment of the present invention will be described with reference to FIGS. In this embodiment, the key switch 24 is provided as a selection switch for selecting whether to set the boom cylinder 9 to the normal operation state or the float state according to the work content.
An interlocking switch 25 is provided which is operated in conjunction with the keyswitch (of course, the interlocking is possible due to the structure of the key switch). The interlocking switch 25, the alarm 28, and the power supply 51 are connected in series to form an electric circuit. Float state selection position contact of the key switch 24 (refers to contact a for regular mode R or contact b for strong mode S shown in FIG. 2).
In the state, the electric circuit is energized. In the above case, the key 47 of the key switch 24 is inserted into the neutral position N (the position indicated by the reference symbol N in FIG. 4, but the electrical circuit 23 shown in FIG. 2 indicates the state at the contacts O and O '). In this state, the key switch 24 is brought into the normal operation selection position contact state, the alarm device 28 is stopped from generating an alarm, and the key 47 is turned into the a contact position or the b contact position. Thus, the key switch 24 is brought into the floating state selection position contact state, the alarm 28 is activated, and the key 47 is pulled out of the neutral position N to select the key switch 24 for normal operation. The position contact state is maintained and the alarm 28 is disabled from generating an alarm. As the alarm 28, for example, a buzzer that emits an alarm sound, or a patrol light (not shown) that emits an alarm light is used.

Next, the operation of the alarm device according to the embodiment of the present invention will be described. In this embodiment, a selection switch for selecting whether the boom cylinder 9 is in the normal operation state or in the floating state is provided. However, since the selection switch is set to the key switch 24, the key switch 2
The key switch 24 can be brought into the normal operation selection position contact state by setting the key 47 of No. 4 to the neutral position N (shown in FIG. 4), and the alarm 28 can be stopped. . The key switch 24 is set to the floating state selection position contact state by turning the key 47 to the a contact position or the b contact position, and the alarm device 28 is set to an alarm sound or an alarm light generation state. can do. Further, by pulling out the key 47 from the neutral position N, the key switch 24 can be held in the normal operation selection position contact state and the alarm 28 can be disabled from generating an alarm. As the alarm 28, one that emits a considerably loud alarm such as a buzzer or one that emits a very strong alarm such as a patrol light is used, so that the operator of the work machine can easily confirm the alarm or the warning light. However, when performing an operation that does not require the boom cylinder 9 to float, the key switch 24 can be immediately returned to the neutral position N. Therefore, when the key switch 24 is returned to the neutral position N, the generation of the alarm is stopped, and even if the operation switch 26 is inadvertently turned on, the work attachment 1 may unexpectedly descend. Trouble can be prevented.

FIG. 6 is a circuit diagram of a main part of a working machine (not shown) of the working machine provided with an alarm device according to another embodiment of the present invention. In the figure, components using the same components as the prior art shown in FIG. 52 is a boom hydraulic remote control valve, 53 is a main pump, 54 is a pilot pump, 55 is an oil tank,
Reference numeral 56 denotes an electric circuit, 57 denotes an interlocking switch that is turned on / off in conjunction with a manual contact switch 30 as a selection switch, 58 denotes an alarm, and 59 denotes a power supply. Next, the configuration and operation of the alarm device of another embodiment shown in FIG. 6 will be described with reference to FIG. In the other embodiment, the manual contact switch 30 is provided as a selection switch for selecting whether to set the boom cylinder 5 to the normal operation state or the float state in accordance with the work content. An interlocking switch 57 that is turned on and off in conjunction with the switch 30 is provided. The interlocking switch 57, an alarm 58, and a power supply 59 are connected in series to form an electric circuit. Sometimes the electrical circuit was energized. Thus, when the manual contact switch 30 is turned on, the alarm 58 issues an alarm. The operator of the work machine easily confirms the alarm and, when performing an operation that does not require the float state of the boom cylinder 5, immediately starts the manual contact switch 3.
0 can be turned off. Therefore, when the manual contact switch 30 is turned off, the alarm is stopped, and even when the float contact return switch 33 is inadvertently turned on, the boom unexpectedly lowers. Coming troubles can be prevented.

In the present invention, the operation of the hydraulic actuator has been described in which the hydraulic cylinder (boom cylinder in this embodiment) can be switched between a normal operation and a float state. However, a specific operation of the hydraulic cylinder is that a part of the return oil discharged from the return-side oil chamber of the hydraulic cylinder (for example, an arm cylinder) is regenerated into the load-side oil chamber of the hydraulic cylinder, In some cases, so-called regeneration has been made possible in which the operating speed of the device is increased. In addition, there is a type in which an operation circuit of a swing motor that performs swing drive of an upper swing body is switched to a short-circuit state to enable so-called swing free. Although it is not a hydraulic actuator, there is a type in which the relief set pressure of the relief valve is switched between low pressure and high pressure.
The alarm device of the present invention can be applied to the hydraulic actuator or the like that can selectively switch between a normal operation and a specific operation according to a task.

[0013]

According to the present invention, there is provided a selection switch for selecting one of a normal operation and a specific operation according to the operation of the hydraulic actuator disposed on the work machine. An interlocking switch is provided for switching operation in conjunction with the selection switch, and the interlocking switch and the alarm are connected to form an electric circuit. And since the selection switch is set as a key switch operated by inserting a key, the selection switch is set to a normal operation selection position contact state by setting a key of the key switch to a neutral position and to the contact state. The alarm generation of the alarm can be stopped. Then, by turning the key to the turning operation state, the selection switch can be set to the contact state of the specific operation selection position and the alarm can be set to the state of generating an alarm sound or an alarm light. Further, by pulling out the key from the neutral position, the selection switch can be held in the normal operation selection position contact state, and the alarm can be disabled from generating an alarm. Further, since the alarm emits an alarm sound or an alarm light, the operator of the work machine easily confirms the alarm sound or the alarm light and performs, for example, an operation that does not require a specific operation (float state) of the boom cylinder. In this case, the selection switch can be immediately returned to the normal operation selection position contact state. Therefore, when the selection switch is returned to the normal operation selection position contact state, the generation of the alarm is stopped, and even if the operation switch is inadvertently turned on, for example, the work attachment may come down unexpectedly. Trouble can be prevented.

[Brief description of the drawings]

FIG. 1 is a side view showing a state in which a work machine equipped with an alarm device of the present invention is performing a compaction work on a backfilled soil surface in a deep groove.

FIG. 2 is an electric circuit diagram showing a hydraulic circuit and an alarm device of the work machine in FIG.

FIG. 3 is a plan view of relevant parts showing the vicinity of a driver's seat of the upper swing body shown in FIG. 1;

FIG. 4 is a view of the switch box in FIG.

FIG. 5 is a view of the mounting state of the operation switch in FIG.

FIG. 6 is a main part circuit diagram of a work machine provided with an alarm device according to another embodiment of the present invention.

FIG. 7 is a float circuit diagram for a boom according to an embodiment of the prior art.

[Explanation of symbols]

 1 Work Attachment 5, 9 Boom Cylinder 6 Boom 19 Float Valve Block 23, 32, 56 Electric Circuit 24 Key Switch 25, 57 Interlock Switch 26 Operation Switch 28, 58 Alarm 30 Manual Contact Switch 33 Return Contact Switch 47 Key 51, 59 Power

Claims (4)

[Claims] A selector switch for selecting an operation of a hydraulic actuator disposed on the work machine between a normal operation and a specific operation in accordance with the operation; and stopping or executing the specific operation. In an operation circuit of a hydraulic actuator having an operation switch capable of switching to a state,
An interlocking switch is provided for switching operation in conjunction with the selection switch, an electric circuit is formed by connecting the interlocking switch and the alarm, and the electric circuit is energized when the selection switch is in a specific operation selection position contact state. An alarm device for a working machine, comprising: 2. An operation circuit of at least one hydraulic cylinder of a work attachment mounted on a work machine is provided with a float switching valve switchable between a normal operation oil passage position and a short-circuit state oil passage position, In the operation circuit, the float switching valve is selectively switched by a selection switch, and at least one component of the work attachment is set in a float state by operating an operation switch in accordance with a work content. An interlocking switch is provided for switching operation in conjunction with the selection switch, an electric circuit is formed by connecting the interlocking switch and the alarm, and the electric circuit is energized when the float switching valve is in the short circuit state oil passage position. An alarm device for a work machine, wherein the alarm device is provided. 3. The selection switch is set as a key switch that is operated by inserting a key, and the key of the key switch is inserted into a neutral position to bring the selection switch into a normal operation selection position contact state. The alarm generation of the alarm device is stopped, the key is turned to the rotating operation state, the selection switch is set to the special operation selection position contact state, the alarm is generated by the alarm device, and the key is set. 3. The work machine according to claim 1, wherein the selector switch is held in a normal operation selection position contact state by being pulled out from the neutral position, and the alarm device is disabled from generating an alarm. Alarm device. 4. The alarm device for a work machine according to claim 1, wherein the alarm device emits an alarm sound or an alarm light.