U.S. patent application number 11/584808 was filed with the patent office on 2007-04-26 for hydraulic excavator with integrated magnetic cross-beam.
Invention is credited to Tobias Glatz.
Application Number | 20070089328 11/584808 |
Document ID | / |
Family ID | 37696136 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070089328 |
Kind Code |
A1 |
Glatz; Tobias |
April 26, 2007 |
Hydraulic excavator with integrated magnetic cross-beam
Abstract
The present disclosure relates to a hydraulic excavator
comprising a magnet attached to its stem or an attached magnetic
cross-beam, in which the power of the magnets is adjustable,
wherein it includes a safety control such that the magnetic force
of the respective magnets is increased upon taking up a load and
upon leaving a safety zone around the load take-up point, the
travel speed of the excavator being switchable at the same time
from a reduced value during load take-up to an increased speed.
Inventors: |
Glatz; Tobias;
(Memmingen-Steinheim, DE) |
Correspondence
Address: |
ALLEMAN HALL MCCOY RUSSELL & TUTTLE LLP
806 SW BROADWAY
SUITE 600
PORTLAND
OR
97205-3335
US
|
Family ID: |
37696136 |
Appl. No.: |
11/584808 |
Filed: |
October 19, 2006 |
Current U.S.
Class: |
37/348 ;
414/728 |
Current CPC
Class: |
E02F 3/435 20130101;
E02F 9/24 20130101; B66C 1/06 20130101; B66C 13/46 20130101; B66C
1/08 20130101 |
Class at
Publication: |
037/348 ;
414/728 |
International
Class: |
E02F 5/02 20060101
E02F005/02 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 20, 2005 |
DE |
20 2005 016 489.5 |
Claims
1. A hydraulic excavator comprising a stem, a magnet coupled to the
stem, in which the power of the magnets is adjustable, and a safety
control such that the magnetic force of the respective magnets is
increased upon taking up a load and upon leaving a safety zone
around the load take-up point, wherein the travel speed of the
excavator can at the same time be switched from a reduced value
during load take-up to an increased speed.
2. The hydraulic excavator as claimed in claim 1, wherein the
safety zone starting from the take-up point of the load to be taken
up by means of the magnets can be determined via sensors in that
the travel distance of the load upon switching on the magnets can
be determined by the sensors.
3. The hydraulic excavator as claimed in claim 2, wherein there are
provided angle, inclination and/or displacement sensors for
determining the travel distance.
4. The hydraulic excavator as claimed in claim 3, wherein an angle
sensor is provided for taking up the angular position .alpha.
between stem and boom, and an inclination sensor is provided for
determining the boom inclination .beta..
5. The hydraulic excavator as claimed in claim 4, wherein the angle
sensor is provided for determining the angle of rotation .gamma. of
the uppercarriage.
6. The hydraulic excavator as claimed in claim 1, wherein a
displacement sensor is provided for detecting the travel distance
of the hydraulic excavator.
7. The hydraulic excavator of claim 1, wherein the magnet is
coupled to the stem via an attached magnetic cross-beam.
8. The hydraulic excavator of claim 1, wherein the magnet is
attached to the stem.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Utility Model
Application No. 20 2005 016 489.5, filed Oct. 20, 2005, which is
hereby incorporated by reference in its entirety for all
purposes.
FIELD
[0002] The present disclosure relates to a hydraulic excavator.
BACKGROUND AND SUMMARY
[0003] For taking up magnetic workpieces, such as cut sheets, it is
known already to provide cranes, such as gantry cranes, with
magnetic load take-up means. These magnetic load take-up means can
comprise single magnets or magnetic cross-beams with a plurality of
magnets. Such magnetic load take-up means are so-called loose load
take-up means for cranes. In this respect, the standard EN 13155
exists, which requests a twofold safety of the material taken up
before dropping the same. When using magnetic load take-up means in
cranes, this leads to the fact that when taking up a load, the
magnet of the magnetic load take-up means is initially only
switched on with reduced power. The load taken up then is initially
lifted slowly. When the load has been moved away from the load
take-up point at least over a certain distance X, the crane
provides a signal to the magnet control which then increases its
power to twice the magnetic force. The twofold safety as requested
by the standard EN 13155 is achieved thereby. In this condition,
the travel speed of the crane can be increased.
[0004] Magnetic load take-up means are also used in excavators. It
is known already to attach a cross-beam with magnets to the stem of
an excavator. In the known embodiment of the hydraulic excavator
with integrated magnetic cross-beam, the increase of the magnetic
force upon load take-up is effected on the part of the excavator
operator. During load take-up, a reduced force is initially applied
onto the magnets of the magnetic cross-beam, as long as the
excavator operator presses an On key. The load then is lifted
slowly by the excavator operator. Upon overtravelling a distance
estimated by the excavator operator, the same releases the On key,
whereby the magnetic force is increased. This manual control of the
magnetic force does, however, not exclude operating errors.
[0005] Therefore, it is the object underlying the present
disclosure to provide a generic hydraulic excavator in which an
automatic safety control is implemented.
[0006] In accordance with the present disclosure, this object is
solved by a hydraulic excavator as described herein. Accordingly, a
hydraulic excavator includes a magnet attached to a stem or a
magnetic cross-beam attached to a stem, which comprises a plurality
of magnets. The power of each of the magnets is adjustable. The
inventive safety control of the hydraulic excavator is effected
such that the magnetic force of the respective magnets is increased
by taking up a load and upon leaving a safety zone around the load
take-up point. Upon leaving the safety zone, which is formed
spherically around the load take-up point, the travel speed of the
excavator at the same time becomes switchable from a reduced value
during load take-up to an increased speed, generally the normal
speed.
[0007] By means of a hydraulic excavator which includes a
corresponding safety control in accordance with the present
disclosure, operating errors can be avoided and the standard EN
13155, which requests the twofold safety of the material taken up
before dropping the same, can safely be observed without the risk
of human operating errors, although the individual movements of the
hydraulic excavator are activated by the excavator operator and, in
contrast to a crane, are not translated by a simple electric
control.
[0008] Further, in some embodiments, the safety zone starting from
the take-up point of the load to be taken up by means of the magnet
can be determined via sensors in that the travel distance of the
load upon switching on the magnets can be determined by the
sensors. In the crane control it is thus determined when the
magnets are switched on. At this time, the position of the
respective sensors is determined. Subsequently, the change in
position by the sensors is monitored over time. Upon leaving a
safety zone extending spherically around the take-up point, the
magnets are switched to full load, which corresponds to the twofold
safety.
[0009] Preferably, there are provided angle, inclination and/or
displacement sensors for determining the travel distance.
[0010] An angle sensor can be provided for receiving the angular
position .alpha. between stem and boom, and an inclination sensor
can be provided for determining the boom inclination .beta..
[0011] In addition, an angle sensor can be provided for determining
the angle of rotation .gamma. of the uppercarriage.
[0012] When the hydraulic excavator is also displaced upon taking
up the load, a displacement sensor can advantageously be provided
for detecting the travel distance.
BRIEF DESCRIPTION OF THE FIGURES
[0013] Further features, details and advantages of the invention
will be explained in detail with reference to an embodiment
illustrated in the drawing. The only Figure (FIG. 1) schematically
shows an excavator with attached magnetic cross-beam.
DETAILED DESCRIPTION
[0014] The hydraulic excavator 10 as shown in FIG. 1 includes a
boom 12 to be inclined by the angle .beta. and a stem 14 pivotally
connected with said boom. The stem 14 can be swivelled with respect
to the boom 12 by the angle .alpha. by means of a hydraulic
cylinder 16. At the front end of the stem 14, there is provided a
magnetic cross-beam 18 with two magnets 20 and 22. The angle
.gamma. is the angle of rotation of the uppercarriage 24 of the
excavator about the slewing ring 26.
[0015] In broken lines, the stem 14' and the magnetic cross-beam
18' are shown at a time at which a load is taken up by the magnets
20' and 22'. At this time, the pivot point 28 of the magnetic
cross-beam 18' on the stem 14' is in a defined position. This
position is detected by correspondingly detecting the angles
.alpha., .beta., .gamma. in the excavator control.
[0016] Subsequently, the inventive safety control of the hydraulic
excavator 10 detects a change in the angles .alpha., .beta.,
.gamma. and at the same time determines whether the radius "X"
formed spherically around the starting point is left. As long as
the pivot point 28 of the cross-beam 18' lies within the spherical
space with the radius X, the magnets 20' and 22' are subject to a
reduced magnetic force, which is sufficient for taking up the load.
During this working phase, the excavator can only be moved with a
reduced speed. Upon leaving the safety radius "X", however, the
magnetic force of the magnets 20 and 22 is increased substantially,
preferably doubled. The magnetic system communicates this power
upshift to the control. Thereupon, the excavator can again be moved
with full travel speed. If the excavator control does not receive
this signal of the magnetic system comprising the magnets 20 and
22, the excavator still can only be moved with the reduced travel
speed.
* * * * *