JPH0827838A - Construction machinery provided with active damping means for cab - Google Patents

Abstract

PURPOSE:To effectively suppress through vibrationproof member vibrations of a cab in a low-frequency zone, installed on a construction machine body. CONSTITUTION:An active damping means 52 including a mass body 74 movably set in a cab 14 is arranged. The displacement of the cab 14 and the movement of the mass body 74 are detected and the mass body 74 is appropriately shifted on the basis of the detection and the inertia force of the mass body is utilized as a damping force of the cab 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction machine in which a cab is attached to a main body of the construction machine via a vibration isolating member.

[0002]

2. Description of the Related Art In construction machines such as hydraulic excavators,
From the viewpoint of ensuring the safety of the driver and isolating noise and vibration, the cab accommodating the driver's seat and the like is attached to the main body of the construction machine through a vibration damping member such as a vibration damping rubber.

[0003]

A considerable vibration is usually generated in the main body of the construction machine by the construction work by a working device such as a bucket mounted on the construction machine and also by the traveling of the construction machine itself. The cab is attached to the main body of the construction machine through a vibration-proof member such as a vibration-proof rubber, but the damping effect of the vibration-proof member is not always sufficient. The person is exposed to severe vibration. In the detailed study by the inventors of the present invention regarding the vibration of the cab mounted on the main body of the construction machine through the vibration isolator, the vibration damping effect of the vibration isolator is sufficient for horizontal vibration especially in the low frequency range. The cab does not work effectively, the cab vibrates at a low frequency, for example around 10 Hz, ie it oscillates laterally (widthwise) and also 15
It has been confirmed that pitching vibration, that is, vibration in the traveling direction, occurs in a low frequency range of about Hz.

The present invention has been made in view of the above facts, and its technical problem is to provide a rolling vibration in a low frequency range as described above of a cab mounted on a main body of a construction machine through a vibration isolating member. And at least one of the pitching vibrations is effectively suppressed.

[0005]

In order to solve the above technical problems, in the present invention, an active vibration damping means including a mass body that can be appropriately moved in a predetermined direction in response to a displacement of the cab in the predetermined direction. Equip.

That is, according to the present invention, a construction machine having a construction machine main body and a cab mounted on the construction machine main body through a vibration isolating member is provided as a construction machine that achieves the above-mentioned technical object. A mass body attached to the cab so as to be movable in any direction, a moving means for moving the mass body, a cab displacement detecting means for detecting a displacement of the cab in the predetermined direction, and a mass body for detecting the displacement of the mass body. Mass body movement detection means for detecting movement in the predetermined direction, displacement of the cab in the predetermined direction detected by the cab displacement detection means, and the predetermined direction of the mass body detected by the mass body movement detection means And a control means for controlling the movement of the mass body by the movement means based on the movement of the cab, and active damping means for suppressing the vibration of the cab.
A construction machine characterized by the above is provided.

In a preferred embodiment, the mass is mounted laterally movably on the rear and upper part of the cab, in view of the fact that rolling vibrations are particularly severe for the driver.
If desired, in addition to or instead of the active damping means, the mass is movable laterally, and a mass movable in the running direction is mounted in the widthwise central part and at the top of the cab. It is also possible to equip it with active damping means. The moving means is preferably composed of a hydraulic actuator.

[0008]

In the construction machine of the present invention, the mass body is appropriately moved in accordance with the displacement of the cab, and the inertial force of the mass body is applied to the cab as a damping force, which effectively vibrates the cab. Suppressed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of a construction machine constructed according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a hydraulic excavator as an example of a construction machine to which the present invention is applied. This hydraulic excavator includes a construction machine body including a lower traveling body 2 and an upper revolving body 4. The lower traveling body 2 includes a pair of endless tracks 6 (only one of which is shown in FIG. 1) arranged at intervals in the width direction. The upper revolving structure 4 is attached to the lower traveling structure 2 via a revolving mechanism 8. A cab 14 is mounted on the upper swing body 4 together with the power housing 10 and the working device 12. The power housing 10 accommodates main parts of a power unit including an engine (not shown), a hydraulic pump 16 (FIG. 4), a pressure oil tank 18 (FIG. 4) and the like. The work device 12 includes a boom 20, an arm 22, a bucket 24, a boom hydraulic cylinder mechanism 26, and an arm hydraulic cylinder 28.
And a bucket hydraulic cylinder mechanism 30. The configuration of the hydraulic shovel shown in the figure other than the active vibration damping means, which will be described later, arranged with respect to the cab 14 does not form a novel feature of the present invention, and may be a configuration well known to those skilled in the art, and therefore, the lower traveling is performed. Detailed descriptions of the body 2, the upper swing body 4, the swing mechanism 8, the power housing 10, the components housed therein, and the working device 12 are omitted.

Referring to FIGS. 2 and 3, the upper revolving structure 8 has a turntable 32 mounted so as to be rotatable about an axis extending vertically, and a skirt 34 fixed to the upper surface of the tanning table 32. Have and.
The skirt 34 is composed of a metal substrate arranged substantially horizontally. The cab 14 is fixed to the upper surface of the skirt 34 via six vibration damping members 36. Three anti-vibration members 36, which can be formed of anti-vibration rubber, are arranged at equal width-direction edges on the lower surface of the cab 14 in the running direction (operating direction in FIG. 3) at equal intervals. 3 at the other edge in the width direction at equal intervals in the traveling direction
Individually arranged. The cab 14 itself has a floor member 38 formed of a metal plate, and the floor member 38 is fixed to the skirt 34 via a vibration isolator 36. The front wall member 40 and the rear wall member 4 are provided on the floor member 38.
2, the cab body including the side wall members 44 and 46 and the ceiling member 48 is fixed. The side wall member 44 is provided with an opening / closing door 50. Further, a part of the front wall member 40, the rear wall member 42, and the side wall members 44 and 46 are formed of a transparent material such as a tempered glass plate, and the view from the inside of the cab 14 is secured. Although not shown, various control levers, switches, and the like are provided in the cab 14 together with the driver's seat.

Continuing the description with reference to FIGS. 2 and 3,
A considerable vibration is generated in the upper swing body 4 due to excavation work by the work device 12, traveling of the construction machine, and the like. The cab 14 is mounted on the skirt 3 of the upper swing body 4 via the vibration-proof member 36.
Although the vibration-damping member 36 does not necessarily have sufficient vibration-damping effect, the cab 14 may be mounted on the vehicle as shown by a two-dot chain line in FIG. It has been empirically proved that rolling vibration is caused in a low frequency range of about 10 Hz, and pitching vibration is caused in a low frequency range of, for example, about 15 Hz as shown by a chain double-dashed line in FIG.

In the illustrated hydraulic excavator, the cab 1
Active damping means, generally designated by numeral 52, is provided for suppressing the rolling vibration of No. 4 described above. The active damping means 52 includes a pair of reinforcing blocks 54 and 56, which can be formed from metal or synthetic resin blocks. One of the reinforcing blocks 54 is the cab 1.
4 on one side of the upper end and the rear end, that is, a corner defined by the inner surface of the ceiling member 48, the inner surface of the rear wall member 42, and the inner surface of the side wall member 44. Not fixed). The other reinforcing block 56 is provided at the other upper corner of the cab 14 and at the other corner of the rear end, that is, at the corner defined by the inner surface of the ceiling member 48, the inner surface of the rear wall member 42, and the inner surface of the side wall member 46. It is fixed by an appropriate fixing means (not shown). A cover member 58 is fixed between the side wall member 44 and the side wall member 46 of the cab 14 to cover the lower and front surfaces of the pair of reinforcing blocks 54 and 56. A hydraulic actuator 60 is attached to the pair of reinforcing blocks 54 and 56. Such hydraulic actuator 60
Is composed of a pair of cylinders 62 and 64 and a common plunger 66. Cylinder 62 is reinforcement block 54
The cylinder 64 is attached to the reinforcing block 56. The cylinders 62 and 64 are aligned with each other and extend substantially horizontally in the lateral direction. Cylinder 62
Protrudes leftward beyond the inner end surface of the reinforcing block 54,
The cylinder 64 projects rightward beyond the inner end surface of the reinforcing block 56. One end of the plunger 66 is slidably inserted into the cylinder 62, and the other end is slidably inserted into the cylinder 64. A pressure oil passage 68 is connected to the closed end of the cylinder 62, and a pressure oil passage 70 is connected to the closed end of the cylinder 64.
Is connected. Pressure passages 68 and 70, which may be formed from flexible hoses, are selectively connected to hydraulic pump 16 and pressure tank 18 via flow control valve 72 (FIG. 4), as further referred to below. . Pressure oil is caused to flow into the closed end side of the cylinder 62 through the pressure oil passage 68, and the pressure oil passage 70
When the pressure oil is made to flow out from the closed end side of the cylinder 64 via the, the plunger 66 is moved to the left in FIG. On the contrary, the pressure oil is introduced into the closed end side of the cylinder 64 through the pressure oil passage 70, and the cylinder 62 is inserted through the pressure oil passage 68.
When the pressure oil is made to flow out from the closed end side of, the plunger 66 is moved to the right in FIG. A mass body 74 is fixed to the central portion of the plunger 66 of the hydraulic actuator 60, and the mass body 74 is moved left and right in accordance with the movement of the plunger 66. The mass body 74 is preferably made of a metal having a relatively high specific gravity such as steel, and may have an appropriate shape such as a relatively thick disc shape.

Continuing the description with reference to FIGS. 2 and 3,
The active damping means 52 also includes a cab displacement detecting means 76 for detecting a lateral displacement of the cab 14. The cab displacement detecting means 76 can be composed of, for example, an ultrasonic displacement detector known per se, which is fixed to the outer surface of the rear end portion of the left side wall member 46 of the cab 14. Such an ultrasonic displacement detector is used in the left side wall member 46 of the cab 14.
To the upright member 82 by radiating ultrasonic waves toward the upright member 82 arranged on the turntable 32 of the upper revolving structure 4 adjacent to and detecting the time required to receive the reflected ultrasonic wave. To detect the distance. Therefore, when the cab 14 is rolling-vibrated and the left side wall member 46 of the cab 14 is laterally displaced, such displacement is detected by the cab displacement detecting means 76. If desired, other suitable forms of cab displacement detection means, such as a detected member such as a permanent magnet fixed to the left side wall member 46 of the cab 14 and a detection means such as a Hall element fixed to the upright member 82, may be used. It is also possible to use a cab displacement detection means composed of Active damping means 52
Further includes a mass body movement detecting means 84 for detecting the movement of the mass body 74. The mass body movement detecting means 84 can also be constituted by, for example, an ultrasonic displacement detector known per se, which is fixed to the inner surface of the reinforcing block 54. Such an ultrasonic displacement detector emits an ultrasonic wave toward the mass body 74 and detects the time required to receive the reflected ultrasonic wave to detect the mass body 74.
Detect the distance to. Therefore, when the mass body 74 is moved to the right or left by the action of the hydraulic actuator 60, such movement is detected by the mass body movement detecting means 84. If desired, other suitable forms of mass movement detection means, such as multiple CCDs (charge coupled devices) arranged laterally at the rear end of the inner surface of the ceiling member 50 of the cab 14 to monitor the movement of the mass 74. ), Can also be used.

Referring to FIG. 4 together with FIGS. 2 and 3, the pressure oil passages 68 and 70 are selectively connected to the hydraulic pump 16 and the pressure oil tank 18 via the flow control valve 72. The flow control valve 72 is composed of a double coil type electromagnetic control valve. The active damping means 52 also includes control means 86, which may consist of a microcomputer. The output signal of the mass body movement detection means 84 is input to the control means 86 together with the output signal of the cab displacement detection means 76, and the control means 86 supplies the control signal to the flow control valve 72 based on the input signal. When the flow control valve 72 is held in the neutral position shown, both pressure oil passages 68 and 70 are isolated from both the hydraulic pump 16 and the pressure oil tank 18 and thus fixed to the plunger 66 and the same. The mass body 74 is kept stationary at a predetermined position without being moved. When the flow control valve 72 is moved from the illustrated position to the right in FIG. 4, the pressure oil passage 68 is connected to the hydraulic pump 16, the pressure oil passage 70 is connected to the pressure oil tank 18, and the pressure oil passage 68 is passed through. The pressure oil is caused to flow into the closed end side of the cylinder 62, and the cylinder 6 passes through the pressure oil passage 70.
The pressure oil is made to flow out from the closed end side of 4, and the plunger 66
And the mass body 74 fixed to this is moved to the left in FIG. When the flow control valve 72 is moved to the left from the position shown in FIG. 4, the pressure oil passage 70 is connected to the hydraulic pump 16, the pressure oil passage 68 is connected to the pressure oil tank 18, and the pressure oil passage 70 is passed through. Pressure oil is made to flow into the closed end side of the cylinder 64, and is made to flow out from the closed end side of the cylinder 62 via the pressure oil passage 68, and the plunger 66 and the mass body 74 fixed to this are shown in FIG. It can be moved to the right. When the mass body 74 is moved to the left in FIG. 2, the inertial force of the mass body 74 causes the reinforcing block 54 to move.
2 and 56, and is transmitted to the cab 14, and the cab 14 is tilted to the left in FIG. Conversely, mass 7
4 is moved to the right in FIG.
The inertial force of 4 is transmitted to the cab 14 via the reinforcing blocks 54 and 56, and the cab 14 is tilted rightward in FIG. Since the mass body 74 is disposed on the upper portion of the cab 14, and the inertial force of the mass body 74 acts on the upper portion of the cab 14, the inertial force of the mass body 74 effectively acts on the cab 14. The tilting movement of the mass body 74 with respect to the cab 14 is controlled so as to suppress the rolling vibration generated in the cab 14. The flow control valve 72 is supplied to the control means 86 based on the output signal of the cab displacement detection means 74 and the output signal of the mass body movement detection means 80.
The control program for controlling the cab is the mass of the cab 14, the spring constant in the rolling vibration of the cab 14, the cab 14
Based on the damping theory in consideration of the damping coefficient in rolling vibration, the mass of the mass body 74, the reduction coefficient of the hydraulic actuator 60, and the damping test in the actual construction machine,
It can be set appropriately.

Thus, in the above-described embodiment, the active vibration damping means 5 relating to the rolling vibration of the cab 14 is used.
However, if desired, instead of or in addition to such active damping means 52, active damping means for pitching vibration of the cab 14 may be provided. In such an active vibration damping means, a mass body is movably mounted on the upper portion of the cab 14 in the traveling direction (that is, the left-right direction in FIG. 3) at the central portion in the width direction of the cab 14, and the cab 14 is displaced in the traveling direction. The mass body can be appropriately moved in the traveling direction.

[0017]

In the construction machine of the present invention provided with the active vibration damping means of the cab, the mass body is appropriately moved in the predetermined direction according to the displacement of the cab in the predetermined direction, and the inertial force of the mass body is the damping force. Acts on the cab as such, thus effectively damping the vibration of the cab. By disposing the mass body and the hydraulic actuator for moving the mass body in the rear part and the upper part of the cab, it is possible to substantially eliminate any adverse effect on the habitability or visibility of the driver in the cab. Further, since the main part of the constituent elements of the active vibration damping means is equipped in the cab itself, there are few configurations to be added to the construction machine body due to the equipment of the active vibration damping means.

[Brief description of drawings]

FIG. 1 is a simplified front view showing the entire hydraulic excavator to which the present invention is applied.

FIG. 2 is a partial side view illustrating a cab and its related configuration in the hydraulic excavator of FIG.

FIG. 3 is a partial front view showing a cab and its related configuration in the hydraulic excavator of FIG.

FIG. 4 is a simplified diagram illustrating an electric and hydraulic control circuit of active vibration damping means in the hydraulic excavator of FIG.

[Explanation of symbols]

2: Lower traveling body (construction machine main body) of hydraulic excavator (construction machine) 4: Lower swing body (construction machine body) of hydraulic excavator (construction machine) 14: Cab 36: Vibration isolator 52: Active vibration damping means 54: Reinforcement block 56: Reinforcement block 60: Hydraulic actuator 62: Cylinder 64: Cylinder 66: Plunger 68: Pressure oil passage 70: Pressure oil passage 72: Flow control valve 74: Mass body 76: Cab displacement detection means 84: Mass body movement detection means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenki Okawa 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Sanryo Heavy Industries Co., Ltd.

Claims (3)

[Claims] 1. A construction machine comprising a construction machine body and a cab mounted on the construction machine body via a vibration isolating member, wherein a mass body movably mounted in the cab in a predetermined direction,
Moving means for moving the mass body, cab displacement detecting means for detecting displacement of the cab in the predetermined direction, and mass body movement detecting means for detecting movement of the mass body in the predetermined direction. And the movement of the mass body by the moving means based on the displacement of the cab in the predetermined direction detected by the cab displacement detection means and the movement of the mass body in the predetermined direction detected by the mass body movement detection means. A construction machine comprising: active vibration damping means for suppressing vibration of the cab, including control means for controlling. 2. The construction machine according to claim 1, wherein the mass body is mounted on a rear portion and an upper portion of the cab so as to be movable in a lateral direction. 3. The construction machine according to claim 1, wherein the moving means is composed of a hydraulic actuator.