JP3455868B2 - Construction vehicle seat damping device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping device for seats of construction vehicles such as construction machines and earthmoving machines.

[0002]

2. Description of the Related Art Construction vehicles generate large vibrations due to traveling on rough terrain, reaction from working machines, and generally because the vehicle body is not equipped with a suspension system. And in the seat of the construction vehicle, up and down direction, front and back direction (running direction),
Large vibration is applied in the left-right direction (width direction). Therefore, in order to alleviate vibrations to the driver sitting in the seat and improve the working environment of driving and manipulating, the seat is provided with various vibration damping means and vibration damping means in consideration. For example, the cab floor on which the seat is installed is attached to the vehicle body frame via a vibration isolating member such as a vibration isolating rubber, and the seat is attached to the cab floor mainly via a so-called suspension mechanism that damps vibrations in the vertical direction. Is done.

Vibration in the front-back direction of the seat (pitching vibration)
Is likely to occur in construction vehicles such as earthmoving machines that often run on uneven terrain, loaders that repeatedly move forward and backward, and hydraulic excavators that are equipped with work machines that overhang forward. This longitudinal vibration occurs in a relatively low frequency range, is uncomfortable for the driver, and is one of the vibrations that need to be improved. For this purpose, for example, a seat is attached to a pedestal to which the seat is attached so as to be movable in the front-rear direction, and the seat is vibrated against the front-back vibration of the pedestal to reduce the vibration acceleration transmitted to the seat. Type vibration control device was developed and adopted.

[0004]

However, in the active type vibration damping device of the above-mentioned form, there is a limit to the stroke of movement of the seat with respect to the pedestal due to mechanical and dimensional constraints of the device, and therefore the end of the stroke is limited. Is provided with a mechanical stopper. When an excessive vibration displacement occurs due to control, the displacement is limited by this stopper. Therefore, the active vibration damping device having the mechanical stopper has the following problems to be solved. (1)
If the range of the movement stroke of the seat is set so as to satisfy all the vibration conditions input to the vibration damping device, the stroke control range becomes large and the device becomes large. And the seat cannot be installed in the limited space of the construction vehicle. (2) If the stroke range is limited to the most commonly used range, a mechanical shock absorber is installed at the stroke end to reduce the collision impact acceleration at the stroke end and reduce the impact on the vibration damping effect. In addition, it is necessary to protect the vibration damping device itself.

The present invention has been made in view of the above facts, and its technical problems are (1) without increasing the size of an active seat vibration damping device, and (2) shock absorbing at the stroke end of the seat. It is an object of the present invention to provide an active seat vibration damping device having a stroke limiting function that does not require a device.

[0006]

In the present invention, in order to solve the above technical problems, a seat vibration damping device is constructed as follows. (1) The calculation means of the vibration control means in the vibration damping device is provided with a stroke limiter element for limiting and controlling the stroke displacement so that the stroke end can be limited without providing a mechanical shock absorbing device. (2) The stroke limiter element controls the displacement speed to decrease as the stroke displacement approaches a predetermined stroke end.

That is, according to the present invention, as a seat vibration damping device for a construction vehicle that solves the above technical problems, a pedestal provided on a vehicle body frame and a seat movably mounted in a predetermined direction on the pedestal are provided. A vibration control means disposed between the pedestal and the seat, wherein the vibration control means is a state of acceleration, velocity or displacement of the pedestal in the predetermined direction. A pedestal state quantity detecting means for detecting an amount, a vibrating means for exciting the seat in the predetermined direction, and a seat state quantity detecting means for detecting a state quantity of acceleration, velocity or displacement of the seat in the predetermined direction. A computing means for computing a vibration force for damping the seat based on output signals from the pedestal state quantity detecting means and the seat state quantity detecting means and outputting the vibration force to the vibration means. The calculation means is
A seat vibration damping device for a construction vehicle, wherein the exciting force is calculated so as to gradually reduce the moving speed of the seat as the seat moves to a predetermined stroke end in the predetermined direction. .

In a preferred embodiment, the seat is mounted so as to be movable in the front-rear direction of the construction vehicle.

As is well known, the pedestal state quantity detecting means and the seat state quantity detecting means for detecting the acceleration, speed or displacement which are the state quantities of the pedestal and the seat in a predetermined direction are acceleration,
Since the value of the velocity or the displacement can be converted into another value by differentiating or integrating it, an appropriate means for detecting either one may be adopted.

In the seat vibration damping device according to the present invention, the movement stroke displacement of the seat movably mounted on the pedestal can be controlled by the vibration control means. Therefore, (1) Stroke displacement is limited in the stroke displacement control loop system. (2) When the stroke displacement approaches the stroke end, the approach speed is gradually reduced. Thus, it is not necessary to increase the size of the damping device, and mechanical impacts at the stroke end are eliminated. And again, the velocity near the stroke end is reduced and the impact is reduced.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, further details will be described with reference to the accompanying drawings illustrating preferred embodiments of a hydraulic excavator that is a typical example of a construction vehicle to which a seat vibration control device configured according to the present invention is applied. Explained.

Explaining with reference to FIGS. 7 and 8, a hydraulic excavator generally designated by reference numeral 2 includes a lower traveling body 4 and an upper revolving body 6 mounted on the lower traveling body 4 so as to be freely rotatable. It has. A cab 8 is provided on the upper swing body 6, a work machine 10 is provided in front of the cab 8 (left side in FIG. 7), and an engine room 12 is provided behind the cab 8 (right side in FIG. 7). . The cab 8 is installed on a swing frame 7 which is a part of a vehicle body frame via a cab floor 9 which is a floor of the cab. Inside the cab 8, a seat 14 which is a driver's seat is provided on the cab floor 9. The hydraulic excavator 2 is moved in the up-down direction and the front-rear direction by the work such as civil engineering construction using the working machine 10 that largely overhangs in the forward direction, and by running the undercarriage 4 on an uneven road surface. Large vibration is generated in the traveling direction and in the left-right direction (width direction). The pitching vibration in the front-back direction of the seat is, for example, 1.5 H in the low frequency range.
Vibration of about z is generated.

Continuing the description with reference to FIG. 6, a seat vibration damping device, generally designated by reference numeral 3, has a pedestal 16 installed on the cab floor 9 and the pedestal 16 in the front-back direction (upper right and lower left in FIG. 6). Seat 1 movably mounted in the direction of connecting
4 and a vibration control means 20 arranged between the pedestal 16 and the seat 14. In pedestal 16 or pedestal 1
A known so-called suspension mechanism (not shown) for damping and damping the vertical vibration of the seat 14 is formed on the whole 6.

Continuing the description with reference to FIGS. 2 to 4, the pedestal 16 is formed in a substantially rectangular parallelepiped shape, and the pedestal 1 is formed as described above.
It is a well-known one in which a suspension mechanism is formed inside 6 or the entire pedestal 16. Seat 1 is on the upper surface of the pedestal 16.
4 is mounted on the seat side mounting member 15 (seat side mounting member 1
5 will be described later in detail), and a pedestal-side mounting member 17 for movably mounting the pedestal 16 in the front-rear direction is fixed to the pedestal 16 by appropriate fastening means (not shown) such as bolts. The pedestal side attachment member 17 is formed by welding steel members to each other or fastening them with bolts or the like. The pedestal-side mounting member 17 includes a plate member 17a mounted on the upper surface of the pedestal 16, and a pair of slide shafts 17b extending in the front-rear direction (left-right direction in FIG. 3) to the left and right (upper and lower in FIG. 3) of the plate member 17a. It has a plurality of brackets 17c for attaching each of the pair of slide shafts 17b to the plate member 17a (one at each of the front and rear ends of one slide shaft 17b, and two in the middle, for a total of four).
A bracket 17d that rotatably supports one end of a linear actuator 24 (the linear actuator 24 will be described in detail later) that is a vibrating means is provided at the center of the front side (the left side in FIG. 3) of the plate member 17a. Has been.

The seat 14 may be of a known type per se, and therefore its detailed description is omitted. The lower surface of the seat 14 is combined with the pedestal side mounting member 17 so that the seat 14
A seat-side mounting member 15 is mounted on the pedestal 16 so as to be movable in the front-rear direction (left-right direction in FIG. 2) via a pair of seat front-rear position adjusting mechanisms 13. The seat front-rear position adjusting mechanism 13 is a slide mechanism which is known per se and which can appropriately select and fix the position of the seat 14 in the front-rear direction, and therefore a detailed description thereof will be omitted. The seat-side mounting member 15 is formed by welding steel members to each other or fastening them with bolts or the like. The seat-side attachment member 15 has a pair of seat front-rear position adjustment mechanisms 13 on its upper surface.
The plate member 15a to which is attached, and the slide shaft 1 of the pedestal side mounting member 17 to the left and right (up and down in FIG. 3) and front and back (left and right in FIG. 3) of the lower surface of the plate member 15a
It has a total of four linear motion bearings 15b that fit into 7b and slide. The plate member 15a further includes the plate member 1
A bracket 15c that pivotally supports the other end of the linear actuator 24 is provided at the center of the rear surface (right side in FIG. 2) of the lower surface of 5a.

As described above, the seat-side mounting member 15 includes the pedestal-side mounting member 17 and the slide shaft 17 of the pedestal-side mounting member 17.
The linear bearing 15b of the seat-side mounting member 15 is slidably fitted to b, so that the linear bearing 15b is mounted so as to be movable in the front-rear direction.

Continuing the description with reference to FIG. 5, the vibration control means 20 vibrates the seat 14 in the longitudinal direction and the acceleration detector 22 which is the pedestal acceleration detecting means for detecting the acceleration in the longitudinal direction of the pedestal 16. A linear actuator 24, which is a vibrating unit, and an acceleration detector 23, which is a seat acceleration detecting unit that detects acceleration in the front-rear direction of the seat 14.
And a controller 26 which is a calculation means for calculating a vibration force for damping the seat 14 and outputting the vibration force to the linear actuator 24 based on the output signals from the acceleration detector 22 and the acceleration detector 23. There is.

As the pedestal state quantity detecting means of the pedestal 16, the linear actuator 2 on the plate member 17a of the pedestal side mounting member 17 having the acceleration detector 22 fixed to the pedestal 16 is used.
4 is attached to an appropriate portion near 4 so as to detect the vibration acceleration in the front-rear direction of pedestal 16 (not shown in FIGS. 2 to 4). As the seat state quantity detecting means of the seat 14, the acceleration detector 23 is substantially fixed to the seat 14 via the seat front-rear position adjusting mechanism 13 and at a proper position on the plate member 15a of the seat side mounting member 15.
Is attached so as to detect the vibration acceleration in the front-back direction (not shown in FIGS. 2 to 4). As the acceleration detector 22 and the acceleration detector 23, a well-known electric vibration pickup such as an electrodynamic type or a piezoelectric type can be used. Acceleration detector 22 and acceleration detector 2
The vibration acceleration detected by 3 is the controller 26
(The controller 26 will be described in detail later).

[0019] an arithmetic unit controller 26 Ru formed by a microcomputer. The controller 26 includes a vibration damping control element 26a (see FIG. 1) and a stroke limiter element 26b (see FIG. 1), and is detected by the acceleration detector 23 and the longitudinal acceleration of the pedestal 16 detected by the acceleration detector 22. Based on the vibration acceleration in the front-rear direction of the seat 14, the front-back vibration force of the seat 14 for controlling the vibration of the seat 14 is calculated and output to the linear actuator 24 (details of the control will be described later. Details).

Linear actuator 24 which is a vibrating means
Is basically composed of a well-known hydraulic cylinder and a hydraulic source (not shown). Linear actuator 24
One end of which is rotatably attached to the bracket 17d on the upper surface of the pedestal side mounting member 17 fixed to the pedestal 16, and the other end of which is substantially rotatably attached to the lower surface of the bracket 15c of the seat side mounting member 15 fixed to the seat 14. It is pivotally supported. The linear actuator 24 includes an electromagnetic switching control valve in its hydraulic source,
The electromagnetic switching control valve is switched by the output signal from the controller 26, and the hydraulic cylinder is expanded and contracted.

A flow of vibration control of the seat vibration damping device 3 will be described with reference to FIG. 1. (1) Vibration of the pedestal 16 in the front-rear direction is caused by an acceleration detector 22 which is a pedestal state quantity detecting means of the pedestal 16. The acceleration is detected and sent to the controller 26 which is a calculation means. (2) Vibration acceleration in the front-back direction of the seat 14 is detected by the acceleration detector 23, which is a seat state amount detecting means of the seat 14, and is sent to the controller 26. (3) The vibration damping control element 26a of the controller 26 compares the vibration accelerations input from the acceleration detector 22 and the acceleration detector 23 to suppress the vibration of the seat 14 against the vibration of the pedestal 16. A vibration direction, a vibration force, a vibration acceleration, a vibration amplitude, etc. are calculated as a vibration force by the vibration suppression control element 26 a included in the controller 26. (4) The calculation result by the vibration suppression control element 26a flows to the stroke limiter element 26b of the controller 26, and as shown by the stroke limiter element 26b in FIG. 1, the vibration amplitude stroke (input stroke) defines the maximum stroke limit. An output stroke is defined such that the stroke is gradually reduced toward the stroke end, and the stroke is output to the linear actuator 24 which is a vibrating means. (5) As the electric signal output to the linear actuator 24, the electromagnetic switching control valve of the linear actuator 24 is operated to flow the pressure oil to the linear actuator 24,
It contains signals to control pressure, flow direction, etc. (6) The linear actuator 24 expands or contracts in response to a signal from the controller 26 to reduce the longitudinal vibration of the seat 14 relative to the longitudinal vibration of the pedestal 16. (7) The vibration of the seat 14 in the front-rear direction, which has been suppressed, is detected by the acceleration detector 23, which is a seat state amount detecting means, and is fed back to the controller 26. (8) Thus, since the stroke displacement is limited in the stroke displacement control loop system and the approach speed is gradually reduced when the stroke displacement approaches the stroke end, it is not necessary to increase the size of the vibration damping device, and Mechanical crash impacts are eliminated and also impacts near the stroke end are mitigated.

The present invention has been described above in detail based on the embodiments. However, the present invention is not limited to the above embodiments, and various changes or modifications can be made within the scope of the present invention. Is. For example, (1) In the present embodiment, the seat vibration damping device configured to damp the vibration in the front-rear direction of the seat has been described, but it is possible to respond to the vertical vibration or the horizontal vibration. With this configuration, the present invention can be similarly applied to vibration in the vertical direction or the horizontal direction. (2) In the present embodiment, a linear actuator composed of a hydraulic cylinder that can be used by an existing hydraulic system of a construction vehicle is used as the vibrating means.
Instead of the hydraulic cylinder, it is also possible to use an actuator in which an electric motor is combined with, for example, a rack, a pinion, or a ball screw. By using an electric motor,
It is possible to improve maintainability and downsize. (3) In the present embodiment, the acceleration detector is used as the state quantity detecting means in the predetermined direction of the seat, but other appropriate means can be used as the state quantity detecting means. . For example, the electric motor is used as a servo motor and a built-in rotation angle detector is used to convert the rotation angle detection output into a displacement in a predetermined direction (relative displacement between the seat and the pedestal), and a second differential result of the converted displacement, The seat acceleration can be known from the sum of the output of the pedestal acceleration detector. By doing so, it is possible to reduce the size of the entire seat vibration damping device. (4) Although a typical driver's seat for one person is disclosed as the seat in the present embodiment, a seat for a plurality of people or a plurality of seats for one person may be mounted. it can. (5) The pedestal in the present embodiment is mounted on the cab floor formed as a pedestal and mounted on the vehicle body frame, but as long as the pedestal can be mounted via vibration damping means Therefore, a part of the body frame may be formed as a pedestal.

[0023]

According to the seat vibration damping device for a construction vehicle constructed according to the present invention, (1) an active type seat vibration damping device is not made large, and (2) shock absorption is provided at the stroke end of the seat. It is possible to provide an active type vibration damping device having a vibration control means having a stroke limiting function and having improved vibration damping performance, which does not require a device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a control flow of a seat vibration damping device configured according to the present invention.

FIG. 2 is a side view of a main part of a seat vibration damping device configured according to the present invention.

FIG. 3 is a plan view seen in the direction of arrow AA in FIG.

FIG. 4 is a rear view as seen in the direction of arrow BB in FIG.

FIG. 5 is an explanatory view showing a simplified configuration of a seat vibration damping device constructed according to the present invention.

FIG. 6 is a perspective view of a seat equipped with a seat vibration damping device configured according to the present invention.

FIG. 7 is a side view of a hydraulic excavator equipped with a seat vibration damping device configured according to the present invention.

8 is a front view of the hydraulic excavator as seen in the direction of arrow C-C in FIG. 7.

[Explanation of symbols]

2: Hydraulic excavator 3: Seat damping device 7: Swing frame (body frame) 14: Seat 16: Pedestal 20: Vibration control means 22: Accelerometer (Pedestal state quantity detection means) 23: Acceleration detector (seat state quantity detecting means) 24: Linear actuator (vibrating means) 26: Controller (calculation means)

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI // F16F 9/50 F16F 9/50 (72) Inventor Yohei Ando 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Heavy Industries, Ltd. (72) Inventor Kiyokatsu Sakakibara 2-5-1, Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Heavy Industries, Ltd. (56) Reference Japanese Unexamined Patent Publication No. 4-129847 (JP, A) Shoukai 61-62632 (JP, U) ) (58) Fields investigated (Int.Cl. ⁷ , DB name) B60N 2/35-2/54 E02F 9/16 F16F 15/02 G05D 19/02

Claims (2)

(57) [Claims] 1. A construction comprising a pedestal provided on a body frame, a seat movably mounted on the pedestal in a predetermined direction, and a vibration control means arranged between the pedestal and the seat. In a vehicle seat vibration damping device, the vibration control means includes a pedestal state quantity detecting means for detecting a state quantity of acceleration, velocity, or displacement of the pedestal in the predetermined direction, and a vibration applying means for exciting the seat in the predetermined direction. A vibrating means, a seat state quantity detecting means for detecting a state quantity of acceleration, velocity or displacement of the seat in the predetermined direction; and a pedestal state quantity detecting means and an output signal from the seat state quantity detecting means. Computing means for computing a vibrating force for damping the seat and outputting the vibrating force to the vibrating means, the computing means according to the movement of the seat to a predetermined stroke end in the predetermined direction. The vibration is applied so that the moving speed of the seat is gradually reduced. Computing the seat damping system for a construction vehicle, characterized in that. 2. The seat vibration damping device for a construction vehicle according to claim 1, wherein the seat is mounted so as to be movable in the front-rear direction of the construction vehicle.