Electrical Work Machine Having a Cooled Battery

Abstract

A work machine, such as a vibration tamper or a vibratory plate machine, includes a work device such as a ground contact plate, and a drive for driving the work device. The drive has an electric drive motor, an electric power accumulator for supplying the drive motor with an electric current, and an inverter installation for inverting the current from the power accumulator and for supplying the current to the drive motor. A cooling device is provided for cooling the power accumulator and the inverter installation. The cooling device has at least one fan installation for generating a cooling airflow which is able to be guided by way of the power accumulator and the inverter installation. The fan installation has a fan and a fan motor that drives the fan. The fan motor is provided separately from the drive motor of the drive.

Claims

1. A work machine comprising: a work device for effecting an operative movement; and a drive for driving the work device, wherein the drive has an electric drive motor, an electric power accumulator for supplying the drive motor with an electric current, and an inverter installation for inverting the current from the power accumulator and for feeding the current to the drive motor; a cooling device for cooling the power accumulator and the inverter installation; wherein the cooling device has at least one fan installation for generating a cooling airflow for cooling the power accumulator and the inverter installation, wherein the fan installation has a fan and a fan motor that drives the fan, and wherein the fan motor is provided separately from the drive motor of the drive.

2. The work machine as claimed in claim 1, wherein the cooling airflow is guided in a path extending between the power accumulator and the inverter installation.

3. The work machine as claimed in claim 2, wherein the fan is disposed in the cooling airflow path between the power accumulator and the inverter installation.

4. The work machine as claimed in claim 1, wherein the work machine includes an upper mass and a lower mass; wherein the lower mass is movable relative to the upper mass; wherein the power accumulator, the inverter installation and the cooling device are disposed on the upper mass; and wherein a ground contact plate for carrying out an operative movement of the work machine is disposed on the lower mass.

5. The work machine as claimed in claim 4, wherein an air-guiding installation is provided on the upper mass; the cooling airflow is at least partially guided through the air-guiding installation; and wherein the air-guiding installation supports the inverter installation.

6. The work machine as claimed in claim 4, wherein a vibration-decoupling installation is provided between the air-guiding installation and the upper mass.

7. The work machine as claimed in claim 4, wherein the power accumulator is held in a storage battery receptacle; the storage battery receptacle and the air-guiding installation are coupled to one another; and wherein the storage battery receptacle and the air-guiding installation are conjointly fastened in a vibration-decoupled manner to the upper mass by way of the vibration-decoupling installation.

8. The work machine as claimed in claim 1, wherein the air-guiding installation has a support structure and a covering installation which are able to be conjointly assembled so as to form a unit; the support structure is configured to support the fan installation and the inverter installation; and wherein the unit formed by the support structure and the covering installation forms an air duct which extends at least between the fan installation and the inverter installation.

9. The work machine as claimed in claim 4, wherein the support structure, conjointly with the fan installation and the inverter installation are fastened as a unit to the upper mass as a unit.

10. The work machine as claimed in claim 4, wherein the air-guiding installation has an air entry opening which is provided upstream of the fan installation and which is disposed downstream of the power accumulator.

11. The work machine as claimed claim 4, wherein the air-guiding installation has an air exit opening which is provided downstream of the inverter installation and which is directed downward.

12. The work machine as claimed in claim 4, wherein an opening, through which the air-guiding installation extends downward in the direction of the lower mass, is provided in the upper mass.

13. The work machine as claimed in claim 4, wherein the lower mass has a vibration exciter which is disposed on the ground contact plate and which is configured to generate vibrations that are able to be utilized by the ground contact plate; and wherein the cooling airflow exits the air guiding installation by way of the air exit opening and is guided in the direction of the vibration exciter on the lower mass.

14. The work machine as claimed in claim 1, wherein the cooling device has at least two fan installations; and wherein the airflows generated by the fan installations are able to be converged so as to form a common cooling airflow.

15. The work machine as claimed in claim 4, wherein an induction opening for the cooling airflow is provided upstream of the power accumulator, on an upper side of the upper mass.

16. The work machine as claimed in claim 4, wherein the work machine is a vibrating tamper or a vibratory plate machine.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0061] These and further advantages and features of the invention will be explained in more detail hereunder by way of examples with reference to the appended Figures in which:

[0062] FIG. 1 in a schematic lateral sectional illustration shows a work machine according to the invention as a vibrating tamper;

[0063] FIG. 2 in a schematic lateral view shows another work machine according to the invention as a vibratory plate compactor;

[0064] FIG. 3 shows a variant of a vibratory plate compactor having an air-guiding installation; and

[0065] FIG. 4 shows a detail pertaining to the variant of FIG. 3.

DETAILED DESCRIPTION

[0066] FIG. 1 schematically shows a vibrating tamper, or vibratory plate compactor, respectively, having an upper mass 1 and a lower mass 2 which is movable relative to the upper mass 1. The upper mass 1 and the lower mass 2 are coupled to one another by a spring installation 3 which is known per se. A ground contact plate 4 for compacting the ground is provided on the lower side of the lower mass 2.

[0067] A drive having an electric motor 5 is provided on the upper mass 1, said electric motor 5 driving in a rotating manner a crank wheel 6 which by way of a crankpin 7 is connected to a con rod 8. The con rod 8 is connected to a tamping piston 9 such that the rotating movement of the crank wheel 6 is converted into a reciprocating movement of the tamping piston 9. The linear movement of the tamping piston 9 is then finally transmitted to the ground contact plate 4 by way of the spring installation 3, said ground contact plate 4 carrying out the actual tamping movement.

[0068] A storage battery 10, which serves as an electric power accumulator, is provided for supplying the electric motor 5 with power.

[0069] The electric current provided by the storage battery 10, in terms of the voltage and the frequency thereof, is converted or inverted, respectively, into a current suitable for the electric motor 5 by an inverter 11 serving as an inverter installation. It can be possible in particular in the process that an alternating current for the electric motor 5 is generated from the direct current stored in the storage battery 10.

[0070] The crank wheel 6, the crankpin 7 and the con rod 8 are accommodated in a crankcase 12 to which the electric motor 5 is also fastened. In one variant, the electric motor 5 can also be largely disposed in the interior of the crankcase 12.

[0071] A gripping installation 13, which is configured as a handlebar and is associated with the upper mass 1, is attached to the upper side of the crankcase 12. A vibration-decoupling installation 14, for example in the form of rubber blocks, for decoupling the gripping installation 13 from vibrations is disposed between the gripping installation 13 and the crankcase 12. As a result, the gripping installation 13 within certain limits is pivotable relative to the remaining upper mass 1, in particular relative to the crankcase 12, so as to protect an operator that grips the handlebar, or the gripping installation 13, respectively, according to the intended use at the right end in FIG. 1 from the influence of excessively intense vibrations.

[0072] The storage battery 10 as well as the inverter 11 are fastened to the gripping installation 13, or are supported by the latter, respectively. It is possible here for the storage battery 10 to be fastened in an interchangeable manner to the gripping installation 13 such that said storage battery 10 can in each case be replaced by a fresh storage battery 10.

[0073] A fan installation 15, which has a fan, for example a ventilator, and a fan motor, is disposed between the storage battery 10 and the inverter 11 in spatial terms.

[0074] The fan installation 15 generates a cooling airflow 16 in that the former inducts air by way of the storage battery 10 and forces said air downstream by way of the inverter 11 until the cooling airflow 16 makes its way back into the environment. The profile of path of the cooling airflow 16 is symbolically illustrated by an arrow in FIG. 1.

[0075] A cover 17, for example a plastic hood, is provided for improved guiding of the cooling airflow 16 as well as for the protection of the various components.

[0076] In a variant not illustrated, the fan installation 15 can also be disposed upstream of the storage battery 10 or downstream of the inverter 11, so as to suitably generate the cooling airflow 16 (cf. direction of arrow).

[0077] FIG. 2 shows another embodiment of the work machine as a vibratory plate compactor. Functionally equivalent or identical components are provided with the same reference signs as in the embodiment of FIG. 1.

[0078] Accordingly, the vibratory plate compactor likewise has an upper mass 1 and a lower mass 2, wherein the lower mass 2 is movable relative to the upper mass 1. To this end, vibration-decoupling elements 20 are provided between the upper mass 1 and the lower mass 2.

[0079] A ground contact plate 4 is configured on the lower mass 2. The electric motor 5, which drives a vibration exciter 21, is disposed on the ground contact plate 4. The vibration exciter 21 can have, for example, one or a plurality of imbalance shafts which are set in rotation by the electric motor 5, which serves as the drive motor, so as to generate the desired vibrations. The vibrations, by way of the ground contact plate 4, are then introduced directly into the ground to be compacted.

[0080] The storage battery 10, which provides the power for the electric motor 5, conjointly with the inverter 11 is disposed on the upper mass 1.

[0081] As in the embodiment of FIG. 1, the fan installation 15 is disposed between the storage battery 10 and the inverter 11, so as to effect the cooling airflow 16 through the storage battery 10 and along the inverter 11. As can be seen, the cooling airflow 16 downstream of the fan installation 15 can be guided in such a manner that the inverter 11 is ideally surrounded by the cooling airflow 16 on all sides, or at least on both sides, respectively. Depending on the design embodiment however, the cooling effect is also sufficient when the storage battery 10 and/or the inverter 11 are passed by a flow on only one side.

[0082] The cover 17 is provided for improved guiding of the cooling airflow 16.

[0083] The gripping installation 13 in the case of the vibratory plate compactor is configured in the form of a drawbar which is able to be guided by an operator and is fastened to the lower mass 2.

[0084] FIG. 3 in a schematic lateral view shows a variant of the vibratory plate compactor of FIG. 2.

[0085] The vibratory plate compactor likewise has an upper mass 1 and a lower mass 2. The ground contact plate 4, to which the vibration exciter 21 is attached, is provided on the lower mass 2. The vibration exciter 21 not only comprises the actual exciter unit but also the electric motor 5 integrated therein.

[0086] The storage battery 10, as well as an air-guiding installation 30, are provided on the upper mass 1.

[0087] The air-guiding installation 30 is a compact unit which, by way of a vertical component, extends perpendicularly. The fan installation 15 for generating the cooling airflow 16 is provided in the air-guiding installation 30. The cooling airflow 16 is symbolized by a plurality of arrows of dissimilar sizes in FIG. 3, wherein the reference sign 16 is not applied to each arrow, so as not to compromise the clarity of the illustration.

[0088] Furthermore, the inverter 11 is held in the air-guiding installation 30. The inverter 11 is disposed so as to be substantially perpendicular and is on both sides impacted by the cooling airflow 16.

[0089] The air-guiding installation 30, at the lower end thereof, penetrates the upper mass 1 in a downward direction, such that the cooling airflow 16 can be discharged by way of an air exit opening 31.

[0090] As can be seen in FIG. 3, the cooling airflow 16 here is deflected in the direction of the vibration exciter 21 and of the electric motor 5 such that said cooling airflow 16 can still be utilized for cooling at that location.

[0091] The vibration exciter 21, or the electric motor 5, respectively, are mounted on the ground contact plate 4 in such a manner that said vibration exciter 21 or said electric motor 5 can be surrounded in the best possible manner by the cooling airflow 16. It can be provided in particular that the cooling airflow 16 can also flow below the electric motor 5, between the electric motor 5 and the ground contact plate 4, so as to improve the cooling effect.

[0092] An induction opening 32, by way of which cooling air can flow in from the environment, is configured on the upstream end, on the upper side of the upper mass 1. The disposal of the induction opening 32 on the upper side makes it possible that the cooling air enters the upper mass 1 ideally free of dust and dirt.

[0093] The cooling airflow 16 is subsequently guided along the walls of the storage battery 10, or through the storage battery 10, respectively.

[0094] The fan installation 15, which generates the cooling airflow 16, is disposed in the upper region of the air-guiding installation 30. An air entry opening 33, by way of which the cooling airflow 16 can enter the air-guiding installation 30 once said cooling airflow 16 has been transported by the fan installation 15, is provided upstream of the fan installation 15 and downstream of the storage battery 10.

[0095] FIG. 4 shows the context of FIG. 3 in an enlarged but reduced illustration.

[0096] The air-guiding installation 30 here is configured so as to be arcuate in order for the cooling airflow 16 to be guided expediently along the inverter installation 11.

[0097] It can also be seen here how the cooling airflow 16, upon exiting the air-guiding installation 30, is divided by way of the air exit opening 31 so as to provide a flow surrounding the vibration exciter 21 including the electric motor 5.