WO2013107613A1

WO2013107613A1 - Ground compacting implement

Info

Publication number: WO2013107613A1
Application number: PCT/EP2013/000033
Authority: WO
Inventors: Michael Steffen; Philip Overfeld; Rudolf Berger; Helmut Braun; Christian Glanz; Dirk Sibila
Original assignee: Wacker Neuson Produktion GmbH & Co. KG
Priority date: 2012-01-16
Filing date: 2013-01-08
Publication date: 2013-07-25
Also published as: EP2804987B1; DE102012000711A1; EP2804987A1

Abstract

The invention relates to an implement (1) for treatment of the ground, having a holding or guiding device (6) for holding the implement (1) in a main working position, an upper mass (2), a lower mass (3) that is arranged below the upper mass (2) in the main working position, is movably coupled to the upper mass (2) by spring means, and has a ground contacting device (4) oriented downward in the main working position, a vibration excitation device for producing a working motion of the lower mass (3), wherein the ground contacting device (4) can be put into an impacting motion directed downward in the main working position, a drive device having an electric motor for driving the vibration excitation device, and an electrical energy store (8) for supplying the electric motor with electrical energy. The energy store (8) is arranged on the upper mass (2) or the lower mass (3) by means of a vibration decoupling device (10, 11) in such a way that the energy store can be decoupled from vibrations.

Description

GROUND COMPRESSOR

description

The invention relates to a hand-held implement for tillage with a mass of at least 15 kg, for example, a rammer or a large or Aufbruchhammer. Working tools for tillage are often driven by internal combustion engines in construction sites. This creates noise and fumes that can affect the health of construction site personnel and the environment. To counteract this, implements of this type are increasingly also being offered with electric motors which are fed from electrical energy stores or accumulators. Because of the high power energy storage of a sufficient power class are needed, which are expensive on the one hand, on the other hand, large and heavy. When installing such energy storage device on the working space is required. It should be noted that the energy storage can be heavily stressed and damaged by the mechanical loads on the implement.

It is known to attach the energy storage to a holding or guiding device of the working device, since the vibrations or shocks required during operation are introduced only damped here. However, a disadvantage of this arrangement is that the center of gravity of the implement is unfavorably influenced and the manageability of, in particular, hand-held implements may deteriorate. Furthermore, in this design it is necessary to provide a relatively long connecting cable for the supply of the electric motor arranged generally below, in which power is consumed, which is then no longer available as a useful line.

The invention has for its object to provide a working device for tillage with a fed from an electrical energy storage electric motor, which allows a higher operating comfort while cost-effective and energy-efficient design of the device.

This object is achieved by a working device for soil compaction according to claim 1. Further developments can be found in the dependent claims. A working device for tillage has a holding device for holding the implement in a main working position, an upper mass, a arranged in the main working position below the upper mass, resiliently movably coupled to the upper mass lower mass with a down in the main working position ground contact device, a Schwingungserre- generating device for generating a working movement of the lower mass, wherein the ground contact device is displaceable in a in the main working position downwardly directed striking motion, an electric motor having a drive device for driving the vibration excitation device and an electrical energy storage for supplying the electric motor with electrical energy. The energy store is decoupled by a vibration decoupling device of vibrations at the upper mass or the lower mass. In one embodiment, the implement may be a soil compaction pestle, a soil compaction vibrating plate, or a soil excavation hammer.

In a further embodiment, the implement may have a weight of at least 15 kg.

The holding device, which may also be referred to as a guide device, allows an operator to hold the implement over the ground to be worked and to guide it during the working movement. It may comprise a guide frame with gripping devices or separate handles not arranged on a guide frame for holding the working device in the main working position. The gripping devices or grips can be arranged laterally in an upper section of the working device approximately at the level of the arms of the operator. The holding device may alternatively or additionally comprise a guide bracket for pulling or pushing the working device. On the holding device operating elements may be arranged, for example for driving the drive device or for interrupting the working movement.

The holding device allows the operator to hold the implement in the main working position during work operation. The implement is thus hand-held or hand-held during operation. If the implement has a large mass, holding the implement involves a high level of physical strain on the operator, who remains with his arms Main working position, make sure the unit is guided and, if necessary, intercept the impact of the implement.

The main working position of the working implement can ensure effective tillage and in particular ensure a direction of impact of the ground contact device with a substantially vertical orientation on the ground located under the implement. This requires that the lower mass and the upper mass are arranged substantially one above the other in the main working position.

The upper mass may have a mass that allows a substantially quiet guiding of the implement. It can, for example in the case of the rammer, comprise a large part of the components necessary for operating the implement, such as the vibration excitation device and / or the drive device with the electric motor, whose mass can thus contribute to the O, without the total weight increase. Alternatively, for example, in the case of the hammer, the upper mass may also have only a protective hood which encloses the lower mass, for example, upwards, laterally and in the direction of the operator and on which the grip device can be arranged.

The lower mass can be resiliently coupled to the upper mass, for example by a spring device and arranged in the main working position below the upper mass. On the lower mass, the ground contact device can be fastened in such a way that the ground contact device is forced into a working movement with impact direction in the direction of the ground by vibrations of the lower mass.

In the case of a rammer or a vibration plate, the ground contact device can have a ground contact plate, which can strike against the ground to be compacted during operation and compact it. In the case of a hammer, the ground contact device may include a breakaway tool such as a breakaway bit to break up the ground. To drive the Aufschlagmeißels the lower mass may have a percussion device with a percussion piston and acted upon by the percussion piston striker, which acts on the Aufschlagmeißel. The percussion piston can be drivable by the arranged on the upper or lower mass drive device and in a striking movement with impact on the striker offset. Beispielswei- se, the percussion piston can be driven by a drive piston of the drive device via a Luftfederschlagwerk.

By means of the vibration excitation device, the lower mass can be vibrated relative to the upper mass and the ground contact device can be displaced into the working movement. In the case of a vibration plate, the vibration excitation device can be arranged on the lower mass and, for generating the vibrations, have at least one imbalance shaft with imbalance mass arranged thereon. In a rammer, the vibration excitation device may be disposed on the upper mass or between the upper and the lower mass and z. have a coupled with the lower mass crank mechanism. In a hammer, the vibration excitation device may be disposed on the upper mass and via a crank mechanism, for example. drive the drive piston, the impulse as already shown on the air spring impact on the percussion piston and by impact on the striker on the Aufschlagmeißel is transferable.

By means of the drive device having the electric motor, the vibration excitation device, for example the imbalance shaft or the crank drive, can be driven. The drive device can be arranged on the upper or Untermas- se and in addition to the electric motor also have other engines, such as an internal combustion engine for a hybrid drive, which can allow the greatest possible use times and independence of power sources. The electric motor may be a universal motor, an induction motor, a switched reluctance motor (SR motor), a DC motor (BDC motor) or a brushless DC motor (BLDC motor).

The electric motor can be powered alone or exclusively by the electrical energy storage. Alternatively, the electric motor can optionally be fed by the energy store or by an external power source, for example a socket of a power supply network, a building power source or a generator.

The energy store may be a rechargeable battery of a suitable power class, for example a lithium-ion or a lithium-polymer rechargeable battery. The energy store can have electrochemical cells and be enclosed by a housing, for example a plastic housing. The housing may encapsulate the electrochemical cells and have electrical connection devices and optionally control and display devices. The energy store can, for example, have a housing with the housing. form the usual unit. Furthermore, the energy storage can also be composed of several accumulators.

Decoupled from vibrations by the vibration decoupling device, the energy store can be arranged on the upper mass or the lower mass. Although in this position it is close to the components which are strongly moving during operation, it can be protected against vibrations, shocks by the vibration decoupling device, which prevents damage and wear. Consequently, it is not necessary to arrange the energy store remotely from the ground contact device, for example on the holding device.

Arranged on the upper or lower mass, the energy store can be arranged in an environment of the drive device or close to the drive device and in particular on the electric motor to be fed. For electrical connection of the electric motor to the energy storage, it is therefore sufficient to provide a short cable, reduced by the power losses or kept low. Consequently, more power is available for generating the working movement of the implement, and the implement can be operated in an energy efficient manner.

The energy storage device and the vibration decoupling device act in this arrangement as a damping system, which has a damping mass which is movable relative to the upper or lower mass and which comprises the mass of the energy reservoir. The absorber mass is coupled via the vibration decoupling device relatively movable to the upper or lower mass.

The vibration decoupling device may include spring means such as a coil spring, an elastomeric member (e.g., rubber) of appropriate stiffness and damping, or other suitable materials such as rubber. As a viscous fluid have. Consequently, the absorber system can be designed as an undamped, damped or viscous absorber. Furthermore, the absorber system may act passively or actively, wherein in an active mode of action, an additional actuator may be provided to enable the absorber mass to vibrate.

When designing the absorber system, the frequency, absorber mass and damping must be optimally matched to each other. The absorber mass can be determined by the mass of the system to be calmed from the upper and lower mass and, for example, be about 5 to 10% of the system mass, but also greater than 10% of the system mass. For example, the absorber mass can be greater than 10% of the system mass if the energy store has a large mass due to the high power requirement of the implement. For weight and space reasons, the absorber mass can also be lower.

The absorber system allows resonances in the region of a natural frequency of a system to be quieted to be considerably damped or even completely eliminated, depending on the tuning of the system. Depending on the nature and occurrence of the vibrations to be eliminated in the working mode, a suitable location can be determined at which the absorber system is to be placed advantageously. The absorber system can be arranged in particular on the upper mass, but also on the lower mass, but not in the power flow between upper and lower mass. However, it can readily be installed in the immediate vicinity of components that are in the force flow.

Furthermore, the movability of the absorber mass, in particular of the energy store, can be determined in such a way that occurring oscillations are best eradicated. For example, in the case of linear oscillations of the upper or lower mass to be killed, the absorber system can be designed as a linear vibration absorber, for example by allowing relative mobility of the energy accumulator mainly in the linear direction.

By the absorber system vibrations in the working mode can be reduced and a quieter movement behavior of the implement can be achieved. As a result, the holding of the working device can be simplified and the operator can be relieved. In addition, the components of the upper mass are relieved because they are only exposed to lower vibrations. This allows for a more cost-effective design of the implement as fewer provisions for component protection must be made and the components can be designed more cost-effectively. When using the energy storage as absorber mass, it is not necessary to provide any additional absorber masses, whereby the total weight of the implement can be kept low. In one embodiment, the energy store and the holding device are arranged on the upper mass.

The arrangement of the energy store on the upper mass, the upper mass is increased relative to the total weight. As a result, vibrations of the upper mass in the working mode can be reduced. With the assembly of the holding device on the upper mass so as to support a quiet holding and guiding the implement by the operator and the operator acting on the hand-arm vibrations can be reduced.

Furthermore, an additional vibration decoupling device such as a rubber buffer and / or a spring device between the upper mass and the holding device may be arranged. As a result, the vibrations, impulses or shocks introduced into the holding device can be further reduced and a smooth hold by the operator can be further supported.

In a further embodiment, the energy store can be arranged in the region of a substantially vertical central axis or main axis of the implement.

The central axis of the implement may correspond substantially to the impact axis of the ground contact device along which the beats are directed substantially perpendicular to the soil to be worked. Along the central axis, initially the lower mass with the bottom contact device oriented downwards and above the upper mass can be arranged at the bottom, which, in this position, strengthens the ground contact by its mass. The center axis may also correspond to an axis of symmetry of the implement with a course substantially perpendicular to the ground. Due to the arrangement of the energy storage in the region of the central axis whose mass also acts in the direction of the strokes for tillage. Furthermore, the center of gravity of the working device lying, for example, in the area of the striking axis is not displaced by the energy store in the horizontal plane, as would be the case with a lateral arrangement of the energy store at a distance from the central axis. The focus and the weight distribution of the implement are therefore favorably influenced, which among other things improves the handling of the implement.

In a further embodiment, the energy store is arranged in the main working position above the upper mass, ie at a side of the upper mass facing away from the ground in the main working position.

This arrangement allows a simple construction, in particular of the upper mass, since within the upper mass there is no separate installation space for the energy supply. is more likely to be provided. Furthermore, the energy storage above the upper mass can be easily arranged in the region of the central axis.

However, to protect the energy storage device in the upwardly exposed position, it may be necessary to provide an additional covering device for protection against heat radiation and for protection against falling objects, for example when used in a construction trench. The cover device can be designed for example by a flat cover plate made of a material reflecting the solar radiation with a suitable strength to protect the energy storage.

In one embodiment, the energy store can be arranged structurally integrated in an environment of the drive device, on the drive device and / or with the drive device.

In this arrangement, the supply of the electric motor can be achieved by the energy storage with a relatively short cabling. This prevents power loss in the cable and enables energy-efficient operation of the implement.

In a further embodiment, the vibration decoupling device may have a spring device and / or a damper device. For example, the vibration decoupling device may comprise a simple spring-damper system, for example with a coil spring and an oil pressure damper.

In one variant, an absorber mass is provided in addition to the energy storage. The additional damper mass, like the energy store, is movable relative to the upper mass and thus causes a reduction of the vibrations, analogous to the energy store. The arrangement of the additional absorber mass relative to the energy store and in particular to the upper mass can be done in various alternative variants, as explained below.

In one embodiment, the absorber mass is arranged on the energy store and, together with the energy store, is connected in a vibration-decoupled manner to the upper mass via the vibration decoupling device. The absorber mass and the energy storage can eg. form a structural unit which is movable relative to the upper mass via the vibration decoupling device. Due to the increased total mass of energy storage and damping mass, the vibration-calming effect is enhanced.

In another embodiment, the absorber mass is vibration-decoupled via its own, further vibration decoupling device with the upper mass, while the energy storage in turn is coupled via the associated vibration decoupling device to the upper mass. Due to the joint effect of absorber mass and energy storage on the upper mass, the vibration is calmed.

In another embodiment, the damper mass is connected to the energy store in a vibration-decoupled manner via its own further vibration decoupling device. The absorber mass is seated e.g. with its own (the other) vibration decoupling device on the energy storage, which in turn is coupled via its vibration decoupling device to the upper mass.

Finally, an embodiment is possible in which the energy store is connected via the vibration decoupling device with the absorber mass and the absorber mass is connected via a separate oscillation decoupling device with the upper mass vibration-decoupled. In this case, the absorber mass is thus effectively arranged between the energy store and the upper mass, wherein it is connected to both components via vibration decoupling device.

In a further embodiment, an electronic control device for controlling the drive device is arranged on the energy store or as the further absorber mass. For example, the control device can be firmly connected to the housing of the energy store. It can further increase the mass of the absorber system and further improve vibration damping without increasing the overall weight of the implement. In this arrangement, the control device is protected against vibration or shock discharges and also supplied directly from the energy storage.

Alternatively, the controller can also be vibration-decoupled from the energy store and thus, as an additional absorber mass, can cancel out vibrations of other frequencies, for example. In one embodiment, the implement may be a hand-held, large-sized hammer.

In a further embodiment, the vibration excitation device may comprise a crank mechanism coupled to the lower mass for displacing the lower mass into the working movement. In this embodiment, the vibration excitation device has no movable imbalance masses for generating the working movement. This embodiment can be used in particular with a hammer or rammer.

These and further features of the invention are explained in more detail below by means of examples with the aid of the accompanying figure. It shows:

1 is a rammer with a vibration decoupled at the

Upper mass arranged energy storage.

1 shows schematically in a lateral sectional view a rammer 1 with an upper mass 2 and a lower mass 3 which is relatively movable relative to the upper mass 2. The lower mass 3 has a padfoot with a ground contact plate 4 serving as a ground contact device.

The upper mass 2 comprises inter alia a drive device (not shown) with an electric motor (not shown) which drives a crank drive (not shown) connected to the lower mass 3. By means of the crank mechanism, the upper mass 2 and the lower mass 3 can be displaced relative to each other in an oscillating relative movement, by which the ground contact plate 4 is forced into a pounding working movement with a direction of impact substantially perpendicular to the ground 5 to be processed. As a result, the bottom 5 can be processed or compacted in the illustrated upright main working position. The direction of impact can essentially follow a central axis of the rammer 1, in the vicinity of which the center of gravity of the rammer 1 is located.

For guiding the rammer 1 by an operator, a holding device 6 is provided on which, for example, an operator handle can be arranged. The holding device 6 is arranged on the upper mass 2 and can be decoupled, for example by a rubber buffer 7 of vibrations of the upper mass 2. For supplying the electric motor, an electrical energy store 8 is provided, which is arranged above the upper mass 2 in the embodiment shown. Structurally integrated with the energy storage 8, a control device 9 is provided for controlling the rammer 1 and in particular of the electric motor. The energy store 8 and the control device 9 can be arranged in the embodiment shown in a common housing.

The housing with the energy store 8 and the control device 9 is coupled via a vibration decoupling device with a spring device 10 and a damper device 1 1 relatively movable with the upper mass 2. The components 8, 9, 10 and 1 1 therefore act as a (dashed framed) absorber system 12, which comprises the absorber mass of the mass of the energy storage device 8 and the control device 8, and in a working operation of the rammer vibrations of the upper mass 2, in particular resonances in the range a natural frequency of the upper mass 2, can significantly reduce.

By the absorber system 12 vibrations and vibrations of the upper mass 2 can be effectively reduced in the working mode. Consequently, components arranged on the upper mass 2, such as, for example, the electric motor and the crank mechanism, with their electrical or mechanical connections, are protected against vibration discharges and shocks. This extends the service life and enables a simpler and thus more cost-effective design of the components.

The introduction of vibration from the upper mass 2 via the rubber buffer 7 in the holding device 6 is further reduced by the absorber system 12. This reduces loads acting on the operator and allows a smooth holding and guiding of the rammer 1 in the working mode.

If the energy store 8 is arranged as shown in the region of the central axis of the rammer 1, the center of gravity of the rammer 1 is not displaced substantially laterally. This facilitates the holding and guiding of the rammer 1 in the main working position.

By arranging the energy storage 8 on the upper mass, the length of a wiring between the energy storage 8 and arranged on the upper mass 2 electric motor can be kept short, whereby power losses are reduced in the cable. As a result, an energy-efficient operation of the rammer 1 can be supported. Furthermore, the arrangement of the control device 9 at the top of the rammer 1 favors good operability by the operator. The control device 9 can be easily supplied by the energy storage 8 in this arrangement.

Claims

claims

1. implement (1) for tillage with

a holding device (6) for holding the working device (1) in a main working position;

an upper mass (2);

- One in the main working position below the upper mass (2) arranged with the upper mass (2) resiliently coupled lower mass (3) with a in the main working position downwardly aligned ground contact device (4);

a vibration excitation device for generating a working movement of the lower mass (3), wherein the ground contact device (4) is displaceable in a downwardly directed striking movement in the main working position;

a driving device having an electric motor for driving the vibration exciting device; and with

an electrical energy store (8) for supplying the electric motor with electrical energy; in which

the energy store (8) can be decoupled from oscillations on the upper mass (2) or on the lower mass (3) by a vibration decoupling device (10, 11).

2. Tool (1) according to claim 1, wherein the energy store (8) and the holding device (6) on the upper mass (2) are arranged.

3. Tool (1) according to claim 1 or 2, wherein the energy store (8) in the region of a substantially vertical central axis of the working device (1) is arranged.

4. Tool (1) according to one of the preceding claims, wherein the energy store (8) in the main working position above the upper mass (2) is arranged.

5. Tool (1) according to one of the preceding claims, wherein the energy store (8) is structurally integrated in an environment of the drive device, on the drive device and / or with the drive device.

6. Implement (1) according to one of the preceding claims, wherein the vibration decoupling device comprises a spring device (10) and / or a damper device (1 1).

7. Tool (1) according to any one of the preceding claims, with an additional to the energy storage (8) provided absorber mass, either

- The absorber mass is arranged on the energy storage device (8) and connected together with the energy storage device (8) via the vibration decoupling device with the upper mass (2) vibration-decoupled; or

the absorber mass is connected in a vibration-decoupled manner via its own further vibration decoupling device to the upper mass (2); or

- The absorber mass via a separate, further Schwingungsentkopplungseinrich- device with the energy storage (8) is connected vibration decoupled; or

the energy store (8) is connected to the absorber mass via the vibration decoupling device and the absorber mass is connected in a vibration-decoupled manner via its own further vibration decoupling device to the upper mass (2).

8. Tool (1) according to any one of the preceding claims, wherein an electronic control device (9) for controlling the drive device to the energy storage (8) or as part of the further absorber mass is arranged.

9. implement (1) according to any one of the preceding claims, wherein the working device is a rammer (1) for soil compaction, a vibrating plate for soil compaction or a hammer for floor breaking.

10. Tool (1) according to any one of the preceding claims, wherein the working device (1) has a weight of at least 15 kg.

1 1. Implement (1) according to one of the preceding claims, wherein the working device (1) is a hand-held large hammer.

12. Implement (1) according to one of the preceding claims, wherein the vibration excitation device with the lower mass (3) coupled crank mechanism for moving the lower mass (3) in the working movement.