JP2002179385A - Cab moving mechanism for construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operator with a wide field of view in a construction machine conventionally where the field of view could be provided only within a limited range since a position of a cab was fixed. SOLUTION: In poles 23a-24b with one ends rotatably attached on a platform 22, other ends are rotatably attached to a sub platform 25 and they horizontally support the sub platform 25 mounted with the operator cab 26. In a slide cylinder 28 extended between the platform 22 and the sub platform 25, one end is rotatably attached to the platform 22 and another end is rotatably attached to the sub platform 25. Since the operator cab 26 is moved along a circular arc defined by lengths of each pole 23 and 24 in a position protruding from a tip of the platform 22 by extension and contraction of the slide cylinder 28, the field of view of the operator 27 can be moved and secured in the same position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine cab moving mechanism for moving a construction machine cab by expanding and contracting a hydraulic cylinder.

[0002]

2. Description of the Related Art In a conventional general construction machine such as a crane, an operator's cab (hereinafter, referred to as an operating cab).
Is mounted on the platform.

FIG. 1 is a side view of a conventional general crawler crane 1. In the crawler crane 1, a front attachment such as a jib 4 is attached to a main body including a crawler 2 which is a lower traveling body and a platform 3 on which a hoisting device and the like are mounted, and a hook 6 is hung from a tip of the jib 4 by a rope 5. It is configured to be lowered.
An operating cab 7 is mounted on the platform 3, and the position of the operating cab 7 is kept unchanged with respect to the platform 3.

[0004] Conventional crawler cranes have a configuration shown in FIG.
As shown in FIG. 5, there is a fixed high cab type crawler crane 9 mounted on the platform 3 with the position of the operating cab 7 raised. In the figure, the same or corresponding parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. Also, as shown in FIG.
There is also a crawler crane 10 of a high post specification in which the height is increased. In this figure, the same or corresponding parts as those in FIG. 1 or FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.
In these crawler cranes 9 and 10, the operator's view can be widened by the higher the position of the operating cab 7 than in the crawler crane 1 shown in FIG.

[0005]

However, in each of the above-mentioned conventional crawler cranes 1, 9, and 10, the harbor work using a lifting magnet, a bucket, or the like requires that the operator in the operating cab 7 be on the lower inboard side. Could not see the scraps etc. directly. Therefore, a signaler and a slinger other than the operator are required separately, and the operator works while communicating with these workers by radio. For this reason, workers are required, and a signaler, a slinger, and the like work directly on the ship, which is dangerous and may lead to a disaster.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has a sub-platform on which a cab is mounted, and both ends of the sub-platform and the platform are rotatable. A plurality of pillars mounted to support the sub-platform in parallel with the platform, one end of the sub-platform being rotatably mounted to the platform at the other end,
A hydraulic cylinder that expands and contracts in a direction intersecting the pillars, thereby rotating the plurality of pillars about the end on the platform side and tilting forward, and protruding the sub-platform from the tip of the platform; And a hydraulic cylinder control means for controlling the expansion and contraction of the cab.

[0007] In such a configuration, the hydraulic cylinder control means controls the expansion and contraction of the hydraulic cylinder, and the sub-platform remains parallel to the platform at a position protruding from the tip of the platform.
It moves on an arc defined by the length of each column. Therefore, the driver's cab mounted on the sub-platform can be protruded from the tip of the platform, and the field of view of the operator can be moved above the work place.

Further, according to the present invention, the hydraulic cylinder control means is provided in a switching valve for switching between supplying and stopping the supply of the pressurized oil to the head side and the rod side of the hydraulic cylinder, and in a cab for switching the switching valve. And a counterbalance valve that balances the load applied to the hydraulic cylinder by applying a back pressure to the hydraulic cylinder.

In such a configuration, when the switching valve is switched to the head side of the hydraulic cylinder by operating the operation switch, the hydraulic cylinder is extended, each column is tilted forward, and the operator's cabin protrudes forward. At this time, the operation cab does not fall suddenly due to the operation of the counterbalance valve. When the switching valve is switched to the rod side of the hydraulic cylinder by operating the operation switch, the hydraulic cylinder contracts, and the cab moves rearward as each column attempts to stand upright. When the switching valve is switched to the hydraulic oil supply stop side of the hydraulic cylinder by operating the operation switch, the expansion / contraction operation of the hydraulic cylinder stops, and the movement of the cab stops. Therefore, the operator can stop the cab at an intended position above the work place by operating the operation switch according to the change in the work situation while staying in the cab.

Further, the present invention is characterized in that the length of the hydraulic cylinder becomes the maximum contraction or maximum extension in a state where the plurality of columns are inclined backward.

In such a configuration, if the sub-platform is held in a state where each column is tilted backward by the expansion and contraction control of the hydraulic cylinder control means, a malfunction occurs in the hydraulic cylinder and the like, and the holding force is lost. Even so, the sub-platform rests on the hydraulic cylinder and rests in a position defined by the retraction or extension of the hydraulic cylinder.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment in which a cab moving mechanism of a construction machine according to the present invention is applied to a crawler crane will be described.

As described above, in the crawler crane, a front attachment such as a jib is attached to a main body composed of a crawler type traveling body as a lower traveling body and a platform, and a hook is hung by a rope from a tip of the jib. It is composed.

FIG. 4 is a side perspective view showing the structure of the operating cab moving mechanism according to the present embodiment, and FIG. 5 is a front perspective view thereof. On the left and right sides of the platform 22, pillars 23a, 23b and pillars 24a,
One end of 24b is rotatably attached. The other end of each of the columns 23a, 23b, 24a, and 24b is rotatably attached to the sub-platform 25, and supports the sub-platform 25 horizontally using the platform 22 as a stand. An operating cab 26 is mounted on the sub-platform 25, and an operating cab 2 is provided.
6 is mounted directly on the platform 22 in FIG.
23a to 24b from the conventional operated cab shown in
It is higher by the length of.

A hydraulic slide cylinder 28 is provided between the platform 22 and the sub-platform 25.
Is spanned. The slide cylinder 28 has one end rotatably mounted on a platform 22 substantially at the center between the columns 23a, 23b, 24a, and 24b, and the other end coaxially with a pin for attaching the columns 23a, 23b to the sub-platform 25. , 23b. The slide cylinder 28 includes a column 23a,
It expands and contracts in the direction crossing 23b. In this embodiment, when the slide cylinder 28 is in the most contracted state, the columns 23a, 23
b, 24a and 24b are tilted backward beyond the top dead center by a predetermined tilt angle.

The end of the slide cylinder 28 on the sub-platform 25 side is coaxial with the mounting pin of the columns 24a, 24b to the sub-platform 25.
4b, it is good also as a structure rotatably attached. In this case, when the slide cylinder 28 is in the most extended state,
The columns 23a, 23b, 24a, 24b are tilted backward beyond the top dead center by a predetermined tilt angle.

Various operating levers in the operating cab 26 are provided along columns 24a and 24b.
The laying portions at both ends of a and 24b are connected to the platform 22 side by a rod 29 forming a link mechanism and a push-pull cable 30 which flexes flexibly.
Therefore, regardless of the position of the operating cab 26, the operation of the various operation levers is reliably transmitted to the platform 22 side.

FIG. 6A is a hydraulic circuit diagram showing a configuration of a hydraulic control circuit for controlling the hydraulic slide cylinder 28, and FIG. 6B is an electric circuit diagram thereof.

The electric circuit includes a main switch 31, an operation switch 32, and solenoids 33 and 34. The solenoids 33 and 34 are each provided with a protection diode in parallel. Solenoid 33, 34
Switches the electromagnetic switching valves 35 and 36 shown in FIG. The operation switch 32 is disposed on a control panel in the operating cab 26 shown in FIGS. 4 and 5, and is manually operated by the operator 27.

The hydraulic circuit comprises a slide cylinder 28 connected to a hydraulic pump 39 via a counterbalance valve 37 and a pilot switching valve 38. This hydraulic circuit and the above electric circuit
This constitutes hydraulic cylinder control means for controlling expansion and contraction of the cylinder.

In such a configuration, the slide cylinder 28 is normally kept in the most contracted state, and the columns 23a, 23
The operating cab 26 is held in a posture in which the 3b, 24a, and 24b are tilted backward by a predetermined tilt angle. In this state, the operator 27 sets the operation switch 32 to the solenoid 33.
, The solenoid 33 is operated to switch the electromagnetic switching valve 35 to the 35b side, and the pilot pressure is transmitted to the pilot switching valve 38. With this pilot pressure,
The pilot switching valve 38 is switched to the side 38a, and the pressure oil from the hydraulic pump 39 is supplied to the head side 28a of the slide cylinder 28 via the check valve 40 of the counterbalance valve 37.
Supplied to When the pressurized oil is supplied to the head side 28a, the slide cylinder 28 extends, and the columns 23a,
3b, 24a and 24b are raised to the vertical state, and the operating cab 26 mounted on the sub-platform 25 reaches the top dead center. Thereafter, as shown in FIG. 4, the operating cab 26 is mounted on each pillar 2 together with the sub-platform 25.
The robot moves on a circular arc defined by the lengths of 3a, 23b, 24a, and 24b in a horizontal posture, and moves forward.

When the operator 27 stops operating the operation switch 32 while the operating cab 26 is moving forward, the operation switch 32 returns to the neutral position, the operation of the solenoid 33 is stopped, and the electromagnetic switching valve 35 is set at 35a. Switch to the side. When the electromagnetic switching valve 35 is switched to the 35a side and the pilot pressure is cut off, the pilot switching valve 38
The position is switched to the position 8b, and the supply line of the pressure oil from the hydraulic pump 39 to the slide cylinder 28 is shut off. Thus, the extension of the slide cylinder 28 stops, and the operating cab 26 stops at a position corresponding to the length of the slide cylinder 28.

When the operating cab 26 moves forward, even if the slide cylinder 28 attempts to extend rapidly due to the mass of the operating cab 26, the rod side 28b
When the hydraulic pressure reaches a predetermined pressure value, the pilot line 41 operates, the valve 43 is pressed against the elastic force of the spring 42, the hydraulic pressure on the head side 28a of the slide cylinder 28 is released, and the back pressure is reduced. Take it. For this reason, the load applied to the slide cylinder 28 and the hydraulic pressure are balanced, so that the slide cylinder 28 does not expand rapidly and the operating cab 26 does not drop rapidly.

When the operation switch 32 is operated to the solenoid 34 side, the solenoid 34 is operated and the electromagnetic switching valve 36 is operated.
Is switched to the 36b side, and the pilot pressure is transmitted to the pilot switching valve 38. By this pilot pressure, the pilot switching valve 38 switches to the side 38c, and the hydraulic pump 3
9 from the rod side 2 of the slide cylinder 28 directly.
8b. When the pressure oil is supplied to the rod side 28b, the slide cylinder 28 contracts, and together with the sub platform 25, the operating cab 26
The robot moves rearward on a circular arc defined by the lengths of a, 23b, 24a, and 24b while maintaining a horizontal posture.

At this time, the oil pressure on the head side 28a increases with the supply of the pressure oil to the rod side 28b of the slide cylinder 28, and the oil pressure on the rod side 28b also increases. However, when the hydraulic pressure on the rod side 28b reaches a predetermined pressure value, the pilot line 41 operates, the valve 43 is pushed against the elastic force of the spring 42, the hydraulic pressure on the head side 28a is released, and a back pressure is applied. Therefore, the slide cylinder 28 contracts at a constant speed. When the operator 27 stops operating the operation switch 32 while the operating cab 26 is moving backward, the operation switch 32 returns to the neutral position,
The operation of the solenoid 34 is stopped and the electromagnetic switching valve 36
Switch to a side. When the electromagnetic switching valve 36 is switched to the side 36a and the pilot pressure is shut off, the pilot switching valve 38 is switched to the position 38b and shuts off the supply line of the hydraulic oil from the hydraulic pump 39 to the slide cylinder 28. Thus, the contraction of the slide cylinder 28 stops, and the operating cab 26 stops at a position corresponding to the length of the slide cylinder 28.

As described above, according to the operating cab moving mechanism according to the present embodiment, the operating cab 26 is positioned at a position protruding from the tip of the platform 22 so that each pillar 23
Since the robot moves on an arc defined by the lengths of a, 23b, 24a, and 24b, the field of view of the operator 27 can be moved above the workplace in front of the platform 22 accordingly. Therefore, in port work or the like, the operating cab 26 can be made to protrude according to the size and tide level of the ship entering the port, and the field of view of the operator 27 can be secured at a position where the inside of the ship can be visually recognized. As a result, since harbor work can be performed under the view of the operator 27,
The number of workers such as signalers can be reduced, and also the reduction of disasters.

Further, the slide cylinder 28 can be stopped at any telescopic position by operating an operation switch 32 provided on a control panel in the operating cab 26. Therefore, the operator 27 stops the operating cab 26 at the intended position by operating the operation switch 32 in accordance with the change of the working condition while being in the operating cab 26, and appropriately secures the intended working field of view. Can be done.

In normal operation, the slide cylinder 28 is
The columns 23a, 23b, 24a, 24b are in the most contracted state in a state of being inclined backward. Therefore, even if the pipes, hoses, etc. of the slide cylinder 28 are cut, oil leakage occurs and the slide cylinder 28 fails, or the counter balance valve 37 fails, the sub-platform 25 keeps the slide cylinder 28 And rests at the position defined by the shortest length of the slide cylinder 28. Therefore, the operation cab 26 does not drop unintentionally, which is safe.

In this embodiment, the columns 23a to 23a
Although the case where the length of 24b is constant has been described, the present invention is not limited to this. For example, the present invention can be applied to a vertical lift type lift cab in which the operating cab 26 moves up and down. In this case, the columns 23a to 24b may be provided with a telescopic function by a cylinder or the like, and the extension of the slide cylinder 28 may be made longer. In such a case, the same operation and effect as in the above embodiment can be obtained.

[0030]

As described above, according to the present invention, the hydraulic cylinder control means controls the expansion and contraction of the hydraulic cylinder, and the sub-platform is positioned parallel to the platform and protrudes from the tip of the platform. Moves on an arc defined by the length of each column. Therefore, the driver's cab mounted on the sub-platform can be protruded from the tip of the platform, and the field of view of the operator can be moved above the work place. As a result, in a harbor work or the like, the operator's cab can be protruded according to the size and tide level of the ship entering the port, and the operator's view can be secured above the work place in the ship. For this reason, since harbor work can be performed under the operator's field of view, the number of workers such as signalers can be reduced, and the number of disasters can be reduced.

When the hydraulic cylinder control means is constituted by a hydraulic circuit having a counter balance valve and the hydraulic cylinder is stopped at an arbitrary telescopic position by operating an operation switch provided in the cab, the operator By operating the operation switch according to the change of the work situation while in the cab, the cab can be stopped at an intended position above the work place. For this reason, the working field of view intended by the operator can be appropriately secured.

In the case where the length of the hydraulic cylinder is set to be the maximum contraction or maximum extension in a state where the plurality of columns are tilted backward, each column is tilted backward by the expansion / contraction control of the hydraulic cylinder control means. If the sub-platform is held in this state, the sub-platform will be supported by the hydraulic cylinder and the hydraulic cylinder will be at its minimum length or maximum extension even if the hydraulic cylinder, etc., loses its holding force due to malfunction. At a position defined by the Therefore, even if the hydraulic cylinder piping or hose is cut or oil leaks or the like occur and the hydraulic cylinder malfunctions, the sub-platform is positioned at the position specified by the minimum retracted length or maximum extension of the hydraulic cylinder. Since the driver's cab does not drop unintentionally, it is safe.

[Brief description of the drawings]

FIG. 1 is a side view of a conventional general crawler crane.

FIG. 2 is a side view of a conventional fixed-type high cab type crawler crane.

FIG. 3 is a side view of a conventional crawler crane of a high post specification.

FIG. 4 is a side perspective view of the cab portion of the crawler crane showing the configuration of the cab moving mechanism according to one embodiment of the present invention.

FIG. 5 is a front perspective view of the cab portion of the crawler crane showing the configuration of the cab moving mechanism according to one embodiment of the present invention.

FIG. 6A is a hydraulic circuit diagram showing a configuration of hydraulic cylinder control means for controlling the operation of the cab moving mechanism according to one embodiment of the present invention, and FIG. 6B is an electric circuit diagram thereof.

[Explanation of symbols]

 22 ... Platforms 23a, 23b, 24a, 24b ... Pillar 25 ... Sub-platform 26 ... Operate cab 27 ... Operator 28 ... Slide cylinder 29 ... Rod 30 ... Push-pull cable 31 ... Main switch 32 ... Operation switch 33,34 ... Solenoid 35, 36 ... electromagnetic switching valve 37 ... counterbalance valve 38 ... pilot switching valve 39 ... hydraulic pump

Claims (3)

[Claims] 1. A sub-platform for mounting a driver's cab at a tip of a platform, and a plurality of sub-platforms having both ends rotatably mounted on the sub-platform and the platform, and supporting the sub-platform in parallel with the platform. And one end of the sub-platform is rotatably attached to the platform, and the other end of the sub-platform expands and contracts in a direction intersecting the column, thereby turning the plurality of columns around the end on the platform side. The hydraulic cab of a construction machine comprising: a hydraulic cylinder for moving and tilting forward to cause the sub-platform to protrude from the tip of the platform; and hydraulic cylinder control means for controlling expansion and contraction of the hydraulic cylinder. Moving mechanism. 2. The hydraulic cylinder control means is provided in a switching valve for switching between supply and stop of pressure oil to a head side and a rod side of the hydraulic cylinder and in the cab for switching the switching valve. The construction machine according to claim 1, wherein the operation switch is provided with a counterbalance valve that balances a load applied to the hydraulic cylinder by applying a back pressure to the hydraulic cylinder. Driver's cab moving mechanism. 3. The operation of a construction machine according to claim 1, wherein the length of the hydraulic cylinder is reduced or extended when the plurality of columns are inclined backward. Room moving mechanism.