WO1999035344A1

WO1999035344A1 - Mobile loading machine with front loading equipment

Info

Publication number: WO1999035344A1
Application number: PCT/EP1998/005602
Authority: WO
Inventors: Heinrich Arck; Robert HÖLLWART; Gustav Leidinger
Original assignee: O & K Orenstein & Koppel Aktiengesellschaft
Priority date: 1998-01-05
Filing date: 1998-09-04
Publication date: 1999-07-15
Also published as: ATE238464T1; DE59808101D1; DE19800164A1; BR9813122A; EP1045941B1; JP2002500301A; AU9266298A; EP1045941A1

Abstract

The invention relates to a mobile loading machine with front loading equipment, especially a construction machine. The inventive loading machine has a lifting frame (1) which is mounted with its rear end on a front frame part (13) of the loading machine (L), in such a way that it can pivot in a lifting frame pivot point (14). Said lifting frame (1) can be raised and lowered by means of at least one lifting cylinder (2). A working shovel (5), fork (5') or similar is connected to the front end of the lifting frame(1) in a shovel pivot point (6) and a tilt lever (3) is connected in a middle area of the lifting frame (1) in a tilt lever pivot point (15). The bottom end of the tilt lever (3) is flexibly connected to a tilt ram (7) in a tilt ram articulation point (8). At the other end, said tilt ram (7) is connected to a frame part (13) in a tilt ram pivot point (11). The top end of the tilt ram (7) is connected to a tilt bar (4) in a tilt bar pivot point (17). The tilt bar (4) is connected to the working shovel (5) by its other end, in a tilt lever articulation point (21) above the shovel pivot point (6). The aim of the invention is to improve the kinematics system. This is achieved by means of special geometrical ratios.

Description

"Mobile loading machine with front loading equipment"

The invention relates to a mobile loading machine with front loading equipment, in particular construction machine, with a lifting frame which is rotatably mounted with the rear end on a front frame part of the loading machine in a lifting frame pivot point and which can be raised and lowered by means of at least one lifting cylinder, at the front end of the lifting frame in one A work shovel, fork or the like is articulated and a rocker arm is articulated in a rocker arm fulcrum in a central region of the lifting frame, the lower end of which is articulated in a rocker cylinder pivot point to a tilt cylinder which is articulated at the other end in a rocker cylinder pivot point on the frame part, and whose upper end is articulated in a tilting rod pivot point on a tilting rod which is articulated with its other end above the bucket pivot point in a tilting rod pivot point on the working bucket.

There are two main areas of application for wheel loaders, namely earthmoving and industrial use. So-called Z-kinematics is common for the first-mentioned application. The Z-kinematics meet the requirements of earth movement in an advantageous manner, since they have great tearing forces in the area of the lower lifting frame position and the bucket tilts back when lifting to avoid material losses during transport, and in the upper one Stroke range when tipping the bucket has sufficient holding forces. However, the course of the holding force over the blade angle in the upper position of the lifting frame is such that it reaches the minimum value of the holding force in the most forward position of the blade center of gravity. That this is still sufficient in this position is due to the fact that a large part of the material has already fallen out of the shovel in this position, so that the load has been greatly reduced. This makes this system unsuitable for industrial use, since here the material to be handled, such as pipes, tree trunks, etc., must be held until the greatest dumping angle is reached or must be tipped back when it is picked up from the stack for the transition to the transport position. Another disadvantage of the Z-kinematics is the course of the angular velocity of the implement in the upper position range of the lifting frame. The speed decreases sharply in the area of large dumping angles, which means that material residues stuck in the bucket can only be knocked out to a limited extent.

Another feature of the Z-kinematics is that the tensile strength designed for the requirements of material loosening has its maximum value in the area of the horizontal blade (bottom) position, but drops sharply with increasing tilt angle. The tear strength at the maximum tilt angle has dropped so far in the lifting height of the bucket that is usual for transport travel that, in the event of strong braking decelerations and / or very uneven terrain, the bucket can no longer be pressed with the necessary force, which causes strong impacts associated with corresponding noise development.

Parallel kinematics are generally used for industrial purposes. Such parallel kinematics enable a blade guide that is parallel via the lifting movement of the lifting frame, and there is also a more favorable course of the holding forces in the upper lifting frame area when tipping out. There is also a continuous increase in the angular velocity, particularly in the last angular range, when tipping out, which enables material stuck in the blade to be tapped out. A disadvantage of this system is that to release the material, the tilting cylinder or cylinders are only subjected to hydraulic pressure on their annular surface, so that they must be dimensioned accordingly large.

Another disadvantage of parallel kinematics is that the tilt cylinders on the front frame of the loader have to be arranged considerably above the articulation point of the lifting frame, which results in a columnar structure of the front frame, which impairs the view of the implement. tigt,

These reasons have led, among other things, to the development of in-house kinematics systems for industrial use, which are based on the advantages of the Z-kinematics, but which eliminate the shortcomings in the described dumping process in the upper lifting frame position with additional elements. This is done primarily by attaching an additional quadrilateral joint between the limbs forming the characteristic Z and the implement. The required holding force can thus be achieved over the entire angular range of the implement. Industrial use requires a largely parallel raising when using the forklift fork, while tilting back when using a shovel or clamp is advantageous in order to bring the center of gravity closer to the vehicle. Since it is not possible to meet these contradicting requirements without further precautions, one is forced to compromise when designing such a system. By cleverly designing the kinematics system, it can be achieved that, with only moderate, acceptable retraction of the initially horizontal stacker fork, the fully tilted bucket or clamp retracts more strongly in the desired manner during the lifting process. The additional The number of links in the kinematic chain allows a far-reaching solution, albeit with certain drawbacks, to meet the requirements of the respective application. Here, too, systems with two tipping mechanisms are opposed to systems with only one tipping mechanism. The former have the disadvantage that their elements lie over the lifting frame cheeks and largely obscure the driver's view of the lateral ends of the goods to be transported in industrial use. Therefore, solutions are cheaper which only have a tipping mechanism arranged in the center, which leaves the view of the ends of the goods uncovered. However, these kinematic systems are more complex due to their additional elements and, because they are arranged in the front lifting frame area, reduce the tipping load and thus also the permissible payload.

From GB 2,266,291 A a generic loading machine with front loading equipment is known, which in principle consists of only a three-part kinematic chain, namely a rocker cylinder, a rocker arm and a rocker arm, the rocker cylinder can be attached to the rocker arm in different positions, so that different kinematics geometries are feasible to meet different requirements. In practice, however, it has been found that this known kinematics is still in need of substantial improvement. The object of the invention is to further improve the kinematics system of a generic loading machine in order to combine all the advantageous properties of the Z-kinematics, the parallel kinematics and the industrial kinematics and to avoid their disadvantages, the effort and thus the costs being those of a conventional Z - should not exceed kinematics.

This object is achieved according to the invention with a mobile loading machine of the type mentioned at the outset in that the following geometric relationships are provided in relation to the length 1 of the lifting frame:

- lifting frame length 1_ between rocker arm pivot point and bucket pivot point: lj / 1 = 0.25 to 0.4,

- Distance a from the rocker arm pivot point to the rocker arm pivot point: a / 1 = 0.3 to 0.35,

- Distance b from the tilt cylinder pivot point to the rocker arm pivot point: b / 1 = 0.14 to 0.17,

- Distance c from the tilt rod pivot point to the bucket pivot point: c / 1 = 0.2 to 0.3,

- Height h of the rocker arm pivot point above the lifting frame axis: h / l = 0.08 to 0.12,

- Length s of the tilt rod s / 1 = 0.4 to 0.5

- vertical distance g of the tilting cylinder pivot point to the lifting frame pivot point: g / 1 = 0.07 to 0.08,

- horizontal distance f of the tilting cylinder pivot point to Lifting frame pivot point: f / 1 = 0.06 to 0.07.

In practice, after lengthy research, it has been found that this special design according to the invention, i.e. Due to the exact position of the pivot points to each other, the lever ratios and the exact lengths of the individual components in their special arrangement, the known kinematics can be significantly improved, while only a simple three-part kinematic chain is required, which consists of a tilt cylinder, a rocker arm and a rocker arm consists.

It is preferably also provided that a second tilt cylinder pivot point for the tilt cylinder is provided on the rocker arm, the distance of the second upper tilt cylinder pivot point from the first lower tilt cylinder pivot point being between 0.01 and 0.12 in relation to the lifting frame length. By simply repositioning the tilt cylinder, the kinematics can be changed from the motion sequence as with a Z-kinematics for earth movement to industrial kinematics with parallel guidance of the implement. The lower tilt cylinder pivot point is preferably provided for earth movement. In the upper position of the lifting frame, the holding force is then sufficient even in the area of the highest demand and follows this approximately up to the maximum tilting angle reducing demand according to the decreasing load moment. This also leads to the fact that in the upper lifting frame position the tearing forces are high even when the implement is in a horizontal position and are comparable to those in the lower lifting frame position.

In contrast to the Z-kinematics, the tear forces remain almost constant over the lifting height of the lifting frame. Therefore, with the system according to the invention, when the material is detached from a solid wall, it can still be broken with high tear strength even in the upper stroke area. The dumping is done by introducing hydraulic oil into the tilt cylinder annulus.

The tipping speed of the implement increases disproportionately in the last rotation angle range, which means that the bucket moves up to a tipping angle of 30 to 35 °, at which the material is largely emptied, at a speed that can be easily controlled by the driver, but the stops at the maximum tipping angle with a high Speed reached, which allows the tapping of stuck material residues. As a result of this speed curve, the emptied bucket tilts back quickly up to approximately its horizontal position, although the full cylinder piston surface is acted on here. The lifting frame advantageously has a crossbeam which is arranged between the rocker arm pivot point and the bucket pivot point and carries the rocker arm by means of the rocker arm bracket. This crossbar is preferably arranged at a distance from the rocker arm pivot point that is greater than the distance between the rocker arm pivot point and the rocker arm pivot point.

To improve the driver's view of the bucket, the tilt cylinder is advantageously arranged approximately parallel to the longitudinal axis of the lifting frame.

When the bucket is emptied into a transport vehicle, there is a risk of the side wall being damaged by the rocker arm. In order to avoid this, the rocker arm is arranged correspondingly far from the bucket pivot point and as high as possible above the frame axis, namely in such a way that the ratio of the distance from the rocker cylinder articulation point to the rocker arm pivot point to the lifting frame length between rocker arm and bucket pivot point is between 0.4 and 0.5.

Further refinements result from subclaims 6 to 8.

In the lower lifting frame position when releasing the material with - lo ¬

The requirement of high tearing forces is applied by applying the hydraulic pressure to the full surface of the tilt cylinder. The tearing forces decrease less with increasing tilt angle than with the Z-kinematics. It is a characteristic of the kinematics according to the invention that the tearing forces increase again at a tipping angle between 35 and 40 °, whereas in the Z-kinematics they would drop towards zero if the tipping was continued. As a result, in the transport position of the blade, the front end of the piston rod of the tilting cylinder is pressed against the tilting rod with high force in the region of the tilting rod pivot point on the blade, so that the latter does not detach from the stop even at higher deceleration values as a result of braking or uneven terrain, but instead maintains their position relative to the lifting frame and thus also to the vehicle. In addition, the property of the rupture force increasing again from the specified range of the tilt angle allows a larger maximum tilt angle to be carried out, as a result of which heaped material can be transported over uneven terrain with a reduced risk of partial loss. The upper part of the rocker arm, which swivels backwards when the implement tilts, frees up a larger mounting space for this, which is restricted in the Z-kinematics by the rocker arm moving forward. The possible tipping angle due to the given tilt cylinder stroke when the blade cutting edge is placed on the ground is so large that the angle is limited not only by the tilt cylinder but also by the stops between the blade and the lifting frame. In this bucket position, this means a tipping angle of significantly more than 90 °, which enables both vertical parting of excavation pit walls and the support by tilting the bucket to free the loader that is stuck in rough terrain. Since the Z-kinematics only has a tipping angle of approx. 70 ° at the floor level of the bucket, the bucket that is pierced into the bottom quickly releases from the bucket during the tilting movement. When pulling off the bottom with teeth or blade edge protruding downwards, the blade lies against the lifting frame, so that the large forces resulting from the pushing force as well as the impacts resulting from the uneven yielding of the base directly through the blade stops in the vehicle to be directed. When pulling backwards with the shovel, the kinematics according to the invention have a considerably higher holding force than the previously known designs, so that this does not give in due to the pressure relief valve of the tilting cylinder responding. In order to reduce the center of gravity as far as possible during transport, material and goods handling, the implement is tilted back during the lifting process. In order to be able to raise the forks in parallel when using the forklift truck, this parallelism can be achieved by changing the articulation point of the tilt cylinder eye on the lower part of the rocker arm. This can be done either by repositioning the tilt cylinder into the second upper tilt cylinder pivot point or by moving the pivot point within the two brackets of the rocker arm using conventional technical means.

The holding force is reduced here, but it still exceeds the requirements that result from the payload permissible for the machine when using the forklift.

In the embodiment of the kinematics according to the invention, there is the possibility of arranging the crossbar in the raised lifting frame position in order to achieve optimal visibility on the working tools as close as possible to the blade pivot point. The arrangement of the tilting cylinder in its position relative to the lifting frame is chosen such that its longitudinal axis is approximately parallel and below the lifting frame axis in each lifting frame position and therefore in the upper lifting range in which the emptying of the Shoveling into the transport vehicles takes place, the selected position results in favorable visibility, since only the relatively thin piston rod of the tilt cylinder is in the driver's field of vision. Even in the lower lifting frame position when picking up material, the tilt cylinder is in a position that does not obstruct the view.

All of these advantages according to the invention, which partly conflict with one another, can surprisingly be achieved by the special kinematics according to the invention with their exact dimensions of the individual elements and their relative position to one another. The basis for the definition of the length ratios is the length of the lifting frame, the ratios are all the more favorable the further the pivot point of the rocker arm to the front lifting frame end, measured horizontally, lies at the ends of the connecting line between the two bearing points.

The invention is explained below with reference to the drawing, for example. This shows in

Fig. 1 in side view of a mobile according to the invention

Loading machine in bucket mode for earthmoving,

2 the loading machine according to FIG. 1 in fork operation for industrial use, 3 to 5 the kinematic conditions of the loading machine according to the invention,

Fig. 6 in side view of a loading machine according to the invention in excavator operation when filling a transport vehicle and

Fig. 7 is a side view of the kinematics with lifting frame and tilted bucket in the transport position.

1 and 2, a mobile loading machine is generally designated L. This loading machine L has a front frame part 13, to which the actual universal kinematics according to the invention is articulated, the exact structure of which can be seen from FIGS. 3 to 6.

The kinematics initially have a lifting frame 1, the lifting frame axis of which is designated by 16. This lifting frame 1 is rotatably supported at its rear end in a lifting frame pivot point 14 on the frame part 13 of the loading machine. The lifting frame 1 usually consists of two parallel frame parts. On the frame part 13, an only indicated lifting cylinder 2 is rotatably mounted, which is articulated with its other end on the lifting frame 1. By actuating the lifting cylinder 2, the lifting frame 1 can thus be raised and lowered, namely by the Lifting frame pivot point 14.

At the front end of the lifting frame 1, a working shovel 5 is articulated in a bucket pivot point 6, and in the region of the front end the lifting frame 1 has a crossbar 10 between its two lifting frame parts, on which two parallel rocker arm brackets 11 are arranged, at the ends of which in a rocker arm pivot point 15 a rocker arm 3 is articulated. The lower end of the rocker arm 3 is articulated in a lower first rocker cylinder pivot point 8 or an upper second rocker cylinder pivot point 9 located above it with a rocker cylinder 7 which is articulated at its other end in a rocker cylinder pivot point 11 on the frame part 13 of the loading machine. The upper end of the rocker arm 3 is articulated in a rocker rod pivot point 17 on a rocker rod 4, which is articulated with its other end above the bucket pivot point 6 in a rocker rod pivot point 21 on the working blade 5.

While the lifting frame 1 can be raised and lowered by actuating the lifting cylinder 2, the rocker arm 3 can be moved with the rocking rod 4 by extending or retracting the piston rod 12 of the rocking cylinder 7 and the bucket 5 can thus be pivoted. If the piston rod 12 of the tilt cylinder 7 is articulated in the tilt cylinder articulation point 8 on the rocker arm 3, the kinematics are suitable for a bucket function, and the function is then the same as for a Z kinematics (FIG. 1).

In contrast, if the piston rod 12 of the tilt cylinder 7 is articulated in the upper second tilt cylinder pivot point 9, which is possible by simply repositioning it, the blade cutting edge or fork is guided parallel upwards, as shown in FIG. 2.

The main ones detailed above

Advantages of the kinematics according to the invention are achieved by special geometric dimensions or leverage ratios, which are shown in detail in FIG. 3.

The following terms are used:

1 = lifting frame length of lifting frame 1,

1 _: = lifting frame length between rocker arm pivot point 15 and bucket pivot point 6, a = distance from rocker arm pivot point 15 to rocker arm pivot point 17, b = distance from rocker arm pivot point 8 to rocker arm pivot point 15, c = distance from rocker arm pivot point 21 to bucket pivot point 6, h = height of rocker arm pivot point 15 - axis 16, s = length of the tilting rod 4, g = vertical distance of the tilting cylinder pivot point 18 to the lifting frame pivot point 14, f = horizontal distance of the tilting cylinder pivot point 18 to the lifting frame pivot point 14, b _: = distance of the tilting cylinder pivot point 9 from the rocker arm point 15, d = clear distance from the lifting frame crossmember 10 to rocker arm fulcrum 15, k = length of extended rocker cylinder 7.

Based on the length 1 of the lifting frame 1, the following dimensions are provided according to the invention:

a / 1 = 0.3 to 0.35, b / 1 = 0.14 to 0.17 c / 1 = 0.2 to 0.3, h / 1 = 0.08 to 0.12, s / 1 = 0.4 to 0.5, g / 1 = 0.07 to 0.08, f / 1 = 0.06 to 0.07,

k / 1 = 0.65 to 0.75. It is also provided that the distance d between the crossmember 10 between the rocker arm pivot point 15 and the blade pivot point 6 is greater than b + r.

5, which shows an enlarged detail A of FIG. 4, a stop 19 of the eye of the piston rod 12 of the tilt cylinder 7 is provided against the eye of the tilt rod 4 or against the blade 6. In addition, as can be seen from FIG. 4, two blade stops 20 are provided against the lifting frame 1 in the tilted-out position.

Fig. 6 shows a loading machine according to the invention in a bucket function when loading a transport vehicle 22 with side walls 23. It can be seen on the one hand that the arrangement of the rocker arm in the ratio c / lj = 0.4 to 0.5 prevents a side wall collision of the rocker arm 3 is guaranteed. It can also be seen that the design according to the invention provides particularly good visibility for the driver of the loading machine L. These visibility conditions are indicated by the reference symbol S, the driver can clearly see both the shovel 5 and the transport vehicle 22 or the side walls 23.

Finally, the universal kinematics according to the invention with lifting frame 1 and tilted blade 6 are shown in FIG. 7 Transport position shown. To apply large holding forces in the tilted-out state of the blade 6, it is provided that in the upper lifting frame position the ratio of the distance m of the axis of the piston rod 12 of the rocker cylinder 7 to the rocker arm pivot point 15 to the distance n of the axis of the rocker rod 4 to the blade pivot point 6, that is to say m / n is on the order of 0.65 to 0.7.

Claims

Claims:

1. Mobile loading machine with front loading equipment, in particular construction machine, with a lifting frame (1) which is rotatably mounted with the rear end on a front frame part (13) of the loading machine (L) in a lifting frame pivot point (14) and which is lifted by means of at least one lifting cylinder (2) - and can be lowered, a working shovel (5), fork (5 ') or the like being articulated at the front end of the lifting frame (1) in a bucket pivot point (6) and in a central region of the lifting frame (1) in a rocker arm pivot point ( 15) a rocker arm (3) is articulated, the lower end of which is articulated in a tilting cylinder articulation point (8) to a tilting cylinder (7) which is articulated at the other end in a tilting cylinder pivot point (11) on the frame part (13) and its upper end is articulated in a tilting rod pivot point (17) on a tilting rod (4) which is articulated at its other end above the blade pivot point (6) in a tilting rod pivot point (21) on the working blade (5), thereby marked inet that the following geometric relationships are provided in relation to the length 1 of the lifting frame (1):

- Lifting frame length 1 _: between rocker arm pivot point (15) and bucket pivot point (6): lj / 1 = 0.25 to 0.4,

- Distance a from the rocker arm pivot point (15) to the rocker arm pivot point (17): a / 1 = 0.3 to 0.35,

- Distance b from the rocker arm pivot point (8) to the rocker arm pivot point (15): b / 1 = 0.14 to 0.17,

- Distance c from the tilt rod pivot point (21) to the bucket pivot point (6): c / 1 = 0.2 to 0.3,

- Height h of the rocker arm pivot point (15) above the lifting frame axis (16): h / l = 0.08 to 0.12,

- Length s of the tilt rod (4) s / 1 = 0.4 to 0.5

vertical distance g of the tilting cylinder pivot point (18) to the lifting frame pivot point (14): g / 1 = 0.07 to 0.08,

- Horizontal distance f of the tilting cylinder pivot point (18) to the lifting frame pivot point (14): f / 1 = 0.06 to 0.07.

2. Loading machine according to claim 1 with a second tilt cylinder pivot point (9) of the tilt cylinder (7) on the rocker arm (3), characterized in that the distance b of the second, upper tilt cylinder pivot point (9) from the first, lower tilt cylinder pivot point (8) to the lifting frame length b ^ l = 0.01 to 0.12.

3. Loading machine according to claim 1 or 2, characterized in that the lifting frame (1) has a cross-beam (10) which between the rocker arm pivot point (15) and the viewing field pivot point (6) is arranged and supports the rocker arm (3) by means of the rocker arm bracket (11).

4. Loading machine according to claim 1 or one of the following, characterized in that the tilt cylinder (7) is arranged approximately parallel to the longitudinal axis of the lifting frame (16).

5. Loading machine according to claim 1 or one of the following, characterized in that the rocker arm (3) is arranged so that the ratio b / li = 0.4 to 0.5.

6. Loading machine according to claim 1 or one of the following, characterized in that two blade stops (20) against the lifting frame (1) in the tilting position and a stop (19) of the eye of the piston rod (12) of the tilt cylinder (7) against the eye of the Tilt rod (4) or against the blade (6) are provided.

7. Loading machine according to claim 1 or one of the following, characterized in that the maximum extended length k of the tilt cylinder (7) is based on the lifting frame length k / 1 = 0.65 to 0.75.

8. Loading machine according to claim 1 or one of the following, characterized in that in the upper lifting frame position, the ratio of the distance m of the axis of the piston rod of the tilt cylinder (7) to the rocker arm pivot point (15) to the distance n of the axis of the tilt rod (14) to Bucket pivot point (6) m / n = 0.65 to 0.7.