JPS62185931A - Vibration-insulating supporter for driver base of construction machine - Google Patents

Abstract

PURPOSE:To eliminate the resonance of vibration by a method in which either of an elastic part to support the front of a driver base and an elastic part to support the rear is set below the gravity center of the driver base, and the other is set above the gravity center. CONSTITUTION:Both right and left ends of the front end of a floor part 8 are supported on a driver base 7. A pair of elastic supporting mechanisms 12A and an elastic supporting mechanism 12B to support the upper end of the right and left-handed columns 13a of a portal crane 13 are provided to elastically support a vehicular body 3. For the mechanism 12B on the rear, a vibration- insulating rubber 17 is provided between a bracket 18 projected backwards from the beam 13b of the strut 13 and a bracket 19 projected forwards from the body 3, as in the case of the mechanism 12A. In this case, horizontal distances a1 and a2 and height distances h1 and h2 are equalized, respectively, in relation to the gravity centers of the mechanism 12A on the front end and the mechanism 12B on the rear. The amounts of rolling and pitching can thus be reduced.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a vibration isolation support device for a cab of a construction machine.

(Prior art) The cab of construction machinery, especially self-propelled vehicles such as road rollers and power shovels, minimizes the vibration of the cab due to engine vibration and vibration of the vehicle body during driving and work. To do this, the four corners of the lower surface of the driver's cab, front, rear, left, and right, are supported by the vehicle body via anti-vibration rubber.

When supporting the driver's cab with vibration isolation using the above structure, the following items are mainly considered.

(A) In order to balance the rotational moment 1- around the center of gravity of the driver's cab when vertical vibration acts on the driver's cab via the anti-vibration rubber, for example, the As shown in the figure, when the anti-vibration rubber is modeled as a spring in the x-y-z direction, if the spring constants Cpl-Cp4 of the anti-vibration rubber provided at the four corners are the same, the driver's cab including the driver The distance between the center of gravity G and each anti-vibration rubber i4 a I
, 2, b, ~b4 is a, = 3°, b1 = b2, b
Each anti-vibration rubber is arranged so that 3=b4, and when the spring constants C21 to C,4 of each anti-vibration rubber are different, a I
X (Cp+ + Cpz) = az×(Cp3
+ Cp4), bl C□+b4 Cp4 = bl
, C22+b3CP:l.

(B) As shown in Figure 10, the weight of the cab is W, the position of the center of gravity of the cab is G, the position of the center of gravity before the vehicle tilts is Go,
G is the center of gravity position when tilted together with the vehicle body.

, G, the center of gravity further moved due to the elasticity of the anti-vibration rubber is 02, the horizontal spring constant of the anti-vibration rubber is 09, and the spring constant in the vertical direction is CP, then the car body is tilted by θ due to ground undulations, etc. At this time, the amount of movement δ of the center of gravity G of the cab is as follows: δ,=lθ+hφ+Wsinθ/(4C,,) However, from the balance of moments, hWsinθ=4bφcpb.

, °, φ=hWsinθ/(4b2Cp'') Therefore, in order to reduce the movement amount δ1, it is necessary to use a hard vibration-proof rubber with large CP and Cq.

(C) When the vehicle turns, etc., when a lateral external force (such as centrifugal force) Q acts on the center of gravity G of the driver's cab as shown in Fig. 11, the amount of movement of the center of gravity G, δ, is δ, = hφ+Q/(
4CQ) However, due to moment balance, hQ=4bφc, b.

, °, φ=hQ/ (4bl C,''), so in order to reduce this amount of movement δ, it is necessary to use a hard vibration-proof rubber with large C9 and CQ, as in the case of CB) above. .

The hardness, shape, and installation location of the vibration-proof rubber that supports the driver's cab are determined from each of the above (A), (B), and (C). 13 or 1 on the upper surface of the vehicle body 103.
Under the driver's cab 110, a cylindrical round vibration-proof rubber 117 shown in FIG. By fixing the mounting brackets 122 and 124 horizontally to the sides and fixing the mounting brackets 122 and 124 to the upper surface of the vibration isolating rubber 117 with fixing bolts 130, a structure is created in which the driver's cab 110 is supported by the vehicle body 103 in an anti-vibration manner. was.

(Problem to be Solved by the Invention) When the above condition (A) is satisfied, the moment in the vertical direction of the driver's cab is balanced and is not achieved, and the vertical vibration of the vehicle body is caused by the vibration isolating rubber. When applied to the cab, the cab vibrates only in the vertical direction without moving around the center of gravity, and each vibration isolator absorbs this vibration in the vertical direction, so a considerable vibration isolating effect can be obtained. Because it is located higher than the swing rubber, it is difficult to overcome the inertial force that acts horizontally on the center of gravity when moving forward, stopping, reversing, and cornering while working on the construction machine, but there is a problem that the driver's cab moves significantly. Ta.

Here, the above achievement and non-coupling means that, for example, when either linear vibration or rotational vibration acts from the vehicle body toward the center of gravity, the vibration occurs in both the linear direction and the rotational direction. (vibration), and conversely, when they vibrate independently, it is called uncoupled (vibration).

Next, when supporting the driver's cab in vibration isolation at a position considerably lower than its center of gravity as described above, as can be seen from the amount of movement δ and δゎ in terms CB) and (C), vibration isolation against vertical vibration is required. The smaller the spring constant and the softer the anti-vibration rubber to increase the effect, the greater the amount of oscillating movement such as rolling and pitching of the driver's cab, which worsens the riding comfort. Therefore, the spring constant cannot be made too small.

Therefore, in the past, in order to minimize the amount of swinging movement of the driver's cab, vibration-proof rubber that is hard and has a large spring constant has been used.

In this case, the natural frequency of the anti-vibration rubber is approximately 10100 Orp.
(equivalent to approximately 16H2) or higher, which coincides with the operating speed range of the engine and often causes significant vibration of the driver's cab due to resonance.

In particular, in the case of vibrating rollers for road compaction, the operating frequency range of the drum is 1,000 to 1,800 rpm, which matches the natural frequency of the anti-vibration rubber, resulting in severe vibration of the driver's cab due to resonance. To prevent this, the frequency range in which the drum can be used is often restricted.

(Means for Solving the Problems) A vibration isolating support device for a cab of a construction machine according to the present invention is a vibration isolating support device for supporting a cab of a construction machine. One of the members and the elastic member supporting the rear portion is disposed below the center of gravity of the driver's cab, and the other is disposed above the center of gravity.

If possible due to the structure of the driver's cab and vehicle body, it is desirable that the height from one elastic member to the center of gravity be approximately equal to the height from the center of gravity to the other elastic member. It is desirable that the horizontal distance from the center of gravity to the other elastic member be approximately equal to the horizontal distance from the center of gravity to the other elastic member.

Furthermore, the elastic member is of a sandwich mount type having a structure in which both end surfaces of a rubber member are formed parallel to each other, a steel plate is bonded to each end surface, and the rubber member is sandwiched between the two steel plates. It may be made of vibration isolating rubber, and it is desirable that the round vibration isolating rubber is disposed so that its compression direction faces horizontally in the vehicle width direction.

It is also desirable to install the battery under the driver's cab to lower the center of gravity.

(Function) In the vibration isolation support device for the cab of a construction machine according to the present invention, one of the elastic member supporting the front part of the cab and the elastic member supporting the rear part is positioned below the center of gravity of the cab. Since the other elastic member is placed above the center of gravity, the driver's cab is supported and restrained even above the center of gravity by the other elastic member, and the amount of movement of the driver's cab due to rolling or pitching is reduced. Not only does this significantly reduce the riding comfort, but also the spring constants of both of the elastic members can be reduced to improve vibration isolation performance against vertical vibrations.

In addition, the spring constant is reduced to make the material softer, and the natural frequency of the driver's cab vibration isolation support device is made lower than the operating speed of the engine and the operating frequency of the drum to prevent resonance and further enhance the vibration isolation effect. I can do it.

In particular, the height from one elastic member to the center of gravity should be approximately equal to the height from the center of gravity to the other elastic member, and the horizontal distance from one elastic member to the center of gravity should be the same as the horizontal distance from the center of gravity to the other elastic member. When configured to be approximately equal to the distance, unachievable support is achieved in which pitching does not occur due to vertical vibration or longitudinal vibration, and rolling does not occur due to horizontal vibration.

(Effects of the Invention) As explained above, according to the anti-vibration support device for the cab of a construction machine according to the present invention, pitching and rolling motions are reduced to improve riding comfort, and the spring constant is reduced. It improves vibration isolation performance against vertical vibrations, and at the same time eliminates resonance with engine vibrations and drum vibrations.

In particular, when the non-quick support is used, pitching and rolling are significantly improved, making it an ideal vibration-proof support device for a driver's cab.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

First, in order to reduce TG movements such as pitching and rolling of the cab DF of construction machinery as much as possible,
A non-quick support mechanism that does not cause pitching due to vertical vibration, does not cause pitching due to longitudinal vibration, and does not cause rolling due to horizontal vibration was studied from the perspective of vibration theory.

In this case, as shown in Figures 1 to 3, the driver's cab DF is modeled as a rigid body, its center of gravity is set to G, the coordinate system is set as shown, and the two positions on the left and right of the front of the driver's cab DF are We investigated a model in which each spring was elastically supported by three sets of springs (spring p, spring q, and spring r), and the two left and right parts of the rear part were elastically supported by three sets of springs (spring p, spring q, and spring r).

In order to simplify the following theoretical analysis, a case will be described in which the same spring is used as the spring P, the same spring is used as the spring q, and the same spring is used as the spring r for all the elastic support points.

Note that the spring p and the spring q are in a plane parallel to the xy plane, and the spring r is parallel to the Z-axis direction, and in the figure C3・Cq −C,
respectively indicate the spring constants of the springs p'q'r.

In the following theoretical analysis, "mechanical mechanics"
(co-authored by Yukiyuki Nakamura and Sekiyasou) (published by Izumi Shobo Publishing), Chapter 13, 2 "Theory of Vibration Isolation" was used as a reference.

The equation of motion for the driver's cab DF is the following six equations.

X-θ-ψ system: y-z-φ system: However, x, y, z: xXy, displacement in the z direction φ, θ, ψ:
Angular displacement around the x, y, and z axes QX% Q,, CL:
X% 1% Force in Z direction M,, Mv, Mz :x,)
'% Moment around the Z axis 18% ry, It : In the sense of force, the first subscript i is the direction of the given unit displacement,
The second subscript j is the direction of the component of the force generated at that time, and the subscripts are 1.2.3 for the x, y, and z directions, respectively. ) However, the synergistic moment of inertia xXy = r v- = r z- = ゛O.

In the above equations (1), (2), and (3), Cls = C
When + b = O, it becomes non-rapid, and the above +41
(5) (In equation 61, when 024=C, ,=O, it becomes uncoupled.

Therefore, as a result of calculating the above CIS, C2 CZa, and C34, C+s=C++ (at ax)
(7) However, Cz = Cpsin”α+C,c
os2αC+6=2(h++hz)(C,5in2α
+c9cos2α)-2(b++bz)(Cp-cq)
sinαcosα(8)CZ4=2 C10(az −
at ) (Q) However, C22=C
,cos”α+CQcos2αC:14=2C
r (ht + hz)
QOI From the above (7) ~ αω formula, Cl5=CI&=C
The conditions for Z4=C34=0 are as follows.

(i) When α=0 (a, -C2) = 0 (h, +h,) = Q (ii) When α≠O (at -at) = 0 (ht + hz) = 0 (C, - Cq)=0 For reference, if h++hz≠0, C
+s=C+h=C24=0, but C34≠0.

Here, additional explanation will be given regarding cases (i) and (ii) above.

α=O means that the spring p is disposed vertically and the spring q is disposed horizontally.

(at - am) = o is the horizontal distance a1 from a pair of elastic members supporting the front part of the driver's cab DF to the center of gravity G, and from the center of gravity G to the pair of elastic members supporting the rear part of the driver's cab DF. and the horizontal distance a2 thereof are equal to each other.

(h+ +h2)=O means that one of the front elastic member and the rear elastic member is below the center of gravity G, and the other is below the center of gravity G.
, and the height distances from each to the center of gravity G are equal.

(C, -Cq)=0 means that the spring constants of spring p and spring q are set equal.

If the above condition (i) or (ii) is satisfied, C+s=C+b=Cza=C34=0, so (
As can be seen from Equations 11 to (6), the non-achieving support is such that pitching does not occur due to vertical vibration, pitching does not occur due to longitudinal vibration, and rolling does not occur due to horizontal vibration. As a result, the swinging (pitching, rolling, etc.) of the driver's cab DF is significantly improved, and a driver's cab DF with excellent riding comfort can be obtained.

Hereinafter, an embodiment of a vibration isolating support device for the driver's cab DF that completely or substantially satisfies the condition (1) above will be described.

As shown in FIGS. 4 and 5, a vibrating roller 1 for compacting roadbeds has a body 3 that can be bent at a hinge part 2 in the center, and a drum 4 is mounted on the front half of the body 3. A pair of left and right rear wheels 5 are provided in the rear half of the vehicle body 3.

In this vibrating roller l, an engine 6 drives a hydraulic pump, a hydraulic motor receiving the oil pressure drives a vibration generating mechanism in the drum 4, and each hydraulic motor receiving the oil pressure drives the drum 4 and the rear. The wheel 5 is driven to rotate.

The driver's cab 7 of the vibrating roller 1 includes a driver's cab 8 and a control base 9.
, a canopy 10 , and a seat 11 provided slightly at the rear of the center of the floor member 8 .

The center line of the floor member 8 coincides with the center line of the vehicle body 3.

At the rear end of the floor member 8, a gate-shaped support 13 having a width of approximately 2 times the width of the floor member 8 is erected, and the legs of the canopy 10 are mounted on the upper ends of the left and right pillars 13a of this portal support 13. 10a is attached.

Further, in order to lower the center of gravity G of the driver's cab 7 as much as possible, battery storage boxes 14 are vertically installed below the left and right sides of the floor member 8, and batteries are stored in each of the battery storage boxes 14. . Note that the lid 14a of the battery storage box 14 is provided on the side of the floor member 8.

The cab 7 has a pair of elastic support mechanisms 12A that support both left and right ends of the front end of the floor member 8, and a pair of elastic support mechanisms 12B that support the upper ends of the left and right column parts 13a of the portal column 13.
It is elastically supported by the vehicle body 3.

The elastic support mechanism 12A is constructed as shown in FIG.

That is, a round anti-vibration rubber 17 is interposed between the upright plaque 15 of the vehicle body 3 and the bracket 16 vertically disposed on the lower surface of the floor member 8, with its compression direction being horizontal to the vehicle width direction. It is a structure.

The vibration isolating rubber 17 is a horizontally oriented short cylindrical rubber member 17a.
A circular steel plate 17b is glued to both end faces of each circular steel plate 17b.
The brackets 15 and 16 are interposed by inserting bolts 17C protruding from the center of the brackets into corresponding bolt holes of the brackets 15 and 16 and tightening them with nuts.

In this case, the vibration isolating rubber 17 is elastically deformed in the compression direction (axial direction) when the driver's cab 7 swings horizontally or rolls, and the vibration isolator 17 is sheared when the driver's cab 7 moves up and down and back and forth. This results in elastic deformation in the direction.

The elastic support mechanism 12B at the rear end is configured as shown in FIG.

That is, a bracket 18 that projects rearward from the beam portion 13t of the portal support 13 and a bracket 1 that projects forward from the vehicle body 3.
It has a structure in which a round vibration isolating rubber 17 is interposed between the elastic support mechanism 12A and the elastic support mechanism 12A.

The positional relationship with respect to the center of gravity G of the left and right elastic support mechanisms 12A at the front end and the left and right elastic support mechanisms 12B at the rear end is as follows:
As shown in Figures 4 and 5, the horizontal path M in the figure
Are al and a2 equal and the height distance? JJ h + and h2 are set equal.

By arranging the four sets of elastic support mechanisms 12A and 12B in this manner, the condition for non-coupled support in case (i) described above is satisfied.

Therefore, in the amount of movement δa and δb of the center of gravity explained in [81 and (C)] of the prior art section, the movement 1hφ due to the tilting of the cab 7 is extremely small or does not occur, so δa#1θ+Wsinθ/( 4Cq), also δ
b#Q/(4Cq).

In this way, since the amount of movement δa and δb of the center of gravity G when the vehicle body 3 tilts or turns becomes smaller, the anti-vibration rubber 17 can be made softer with a smaller spring constant to enhance the anti-vibration effect. Resonance can be eliminated by making the natural frequency of the driver's cab vibration isolation support device smaller than the operating rotational speed of the engine and the operating frequency of the drum 4.

Furthermore, since the compression direction of the vibration isolating rubber 17 is oriented in the horizontal direction of the vehicle width direction, the vertical vibration and longitudinal vibration of the vehicle body 3 are absorbed by the springs of the vibration isolating rubber 17 with a small spring constant in the shear direction, and the vibration of the vehicle body 3 is Vibration in the left and right direction is received by the spring in the compression direction of the large spring constant of the vibration isolating rubber 17, so that movement and rolling of the driver's cab 7 in the left and right direction can be significantly reduced.

In addition, by placing the battery below the floor member 8, the center of gravity G of the driver's cab 7 can be lowered, and the amount of rolling and pitching of the driver's cab 7 can be reduced. (!: By reducing h2, the entire anti-vibration support structure can be downsized.

Next, the above embodiment may be partially modified as follows.

As shown in Fig. 7, in the case of a cabin type cab 7A,
Since the center of gravity G of the driver's cab 7A moves upwards somewhat, the height distances h1 and h2 are no longer equal and become >h2.

In this case, the conditions for non-quick support are not completely satisfied, but the support structure is similar to non-quick support,
Vibrations in the cab 7A are significantly improved when compared to conventional support structures.

Even in the case of this cabin type driver's cab 7A, by moving the elastic support mechanism 12B at the rear end upward as shown in FIG. 8, the height distances h1 and h2 in the figure can be set equal, and It is also possible to provide coupled support.

In the above embodiment, the cabs 7 and 7A are supported by a total of four elastic support mechanisms 12A and 12B, two sets on the front side and two sets on the rear side. It is also possible to support the device by a total of three sets of elastic support mechanisms, one set on the rear side, and to provide non-achievement support.

Further, as the round vibration isolating rubber 17, it is also possible to use the same conventional ones as shown in FIGS. Good too.

In the above embodiment, an elastic support device that satisfies the non-achieving support condition in (i) above was described, but an elastic support device that satisfies the non-coupled support condition in (ii) above when α≠0 is described. Of course, the support device can also be realized using the same concept as the above embodiment.

Furthermore, the anti-vibration support device according to the present invention is applicable not only to the driver's cab 7/7A of the vibrating roller 1 but also to power shovels, bulldozers,
It can be applied to the cabs of various construction machines such as wheel loaders.

[Brief explanation of drawings]

Among the drawings, FIGS. 1 to 8 relate to an embodiment of the present invention, in which FIG. 1 is a perspective view of the driver's cab modeled as an elastic rigid body, FIG. 2 is a front view, and FIG. 3 is a front view. is also a rear view, FIG. 4 is a side view of the vibrating roller, FIG. 5 is a plan view of the main parts of the vibrating roller, FIG. 6 is a front view of the elastic support mechanism on the left side of the front of the driver's cab, and FIG. 7 is a side view of the vibrating roller. FIG. 8 is a side view of the vibrating roller of the first modified example; FIG. 8 is a side view of the vibrating roller of the second modified example;
Figures 9 to 14 relate to the prior art; Figure 9(a)
・(b) ・(c) are a side view, front view, and rear view of the driver's cab modeled as an elastically supported rigid body, respectively.
The figure is an explanatory diagram showing the movement of the center of gravity of the driver's cab when the vehicle body is tilted. Figure 11 is an explanatory diagram showing the movement of the center of gravity of the driver's cab when a lateral inertial force is applied. Figures 13 and 14 are respectively vibration proofing. Vertical cross-sectional view of rubber: 1. Vibration roller, 7. DF.
・Driver's cab, 8...Floor parts, 9...Control base, 10...
Ki + Novi, 11... Cab dust, 12A, 12B
...Elastic support mechanism, 15, 16, 18, 19...Bracket, 17...Round anti-vibration rubber, 17a...Rubber member, 17b...Circular steel plate. Patent applicant: Kawasaki Heavy Industries, Ltd. Figure 12 Figure 13 Figure 14 Figure 1 Figure 2

Claims (6)

[Claims] (1) In a vibration isolation support device that supports the cab of a construction machine, one of the elastic member that supports the front part of the cab and the elastic member that supports the rear part of the cab are arranged below the center of gravity of the cab. A vibration isolation support device for a cab of a construction machine, characterized in that the other is disposed above the center of gravity. (2) Vibration isolation for the cab of a construction machine according to claim 1, wherein the height from the one elastic member to the center of gravity is approximately equal to the height from the center of gravity to the other elastic member. Support device. (3) The construction machine according to claim 1 or 2, wherein the horizontal distance from one elastic member to the center of gravity is approximately equal to the horizontal distance from the center of gravity to the other elastic member. Anti-vibration support device for the driver's cab. (4) The above-mentioned elastic member is a sandwich mount type that has a structure in which both end faces of a rubber member are formed parallel to each other, a steel plate is bonded to each end face, and the rubber member is sandwiched between the two steel plates. A vibration isolating support device for a cab of a construction machine as set forth in claim 1, which is constructed of vibration isolating rubber. (5) The sandwich mount type anti-vibration rubber is disposed so that its compression direction is oriented horizontally in the vehicle width direction and its shear direction is oriented in the vertical and longitudinal directions of the vehicle body. Anti-vibration support device for the cab of construction machinery. (6) The anti-vibration support device for a driver's cab of a construction machine as set forth in claim 1, wherein a battery is attached under the floor of the driver's cab in order to lower the center of gravity of the driver's cab.