Level indicating mechanism for a work machine

A level indicating mechanism for indicating to a machine operator the relative level position of a work machine includes a circular ring magnet and a bullseye level instrument positioned within the ring magnet. A potting material surrounds the level instrument and connects it to the ring magnet. The level indicating mechanism is adapted to be removably secured to portions of the work machine and be visable to the machine operator. The angular orientation of the work machine is adjustable by stabilizing apparatus to bring the work machine to a level position with respect to the ground surface.

TECHNICAL FIELD 
This invention relates generally to excavating type work machines and more 
particularly to apparatus which is adapted to indicate the relative level 
position of the work machine. 
BACKGROUND ART 
Excavating type machines, including backhoe loader machines, are equipped 
with a bucket mechanism for digging trenches and other excavations. Such 
trenches are used for installing underground utilities, pipelines, and 
other buried apparatus. These excavations are often in close proximity to 
buildings, sidewalks, or other buried utilities. To prevent damage to such 
adjacent structures and/or other buried objects, it is important that such 
excavations be as straight, in a vertical plane, as possible. Most 
excavating type machines are equipped with some type of stabilizing arms 
to remove the machine weight from the machine wheels and stabilize the 
machine during the digging operation. These stabilizing arms are also used 
to level the machine with respect to the surface which supports the 
machine. However, such leveling operation is only an approximation and is 
dependant entirely on the judgment of the machine operator. If the 
operator's judgment is not good, the excavation may be angled 
considerably, which may result in damage to adjacent structures or to 
previously buried cables or pipelines, or make machine harder to control 
as digging arm goes "over center" and accelerates. 
The present invention is directed to overcoming one or more of the problems 
as set forth above. 
DISCLOSURE OF THE INVENTION 
In one aspect of the present invention, a level indicating mechanism for 
indicating the relative level position of a work machine includes a 
circular magnet and a level instrument positioned within the magnet. The 
level instrument and the magnet are connected together by a potting 
material which surrounds the level instrument. The level instrument can 
include a bullseye bubble type level and the level indicating mechanism is 
adapted to be removably secured to the work machine. 
Excavating machines, including multiple task performing backhoe loading 
machines, are often utilized to dig trenches and make excavations in areas 
that are adjacent to buildings and structures, or are adjacent to existing 
buried cables or pipelines. To prevent damage to such existing structures 
or buried utilities, it is important that the trench or excavation be 
straight and as vertically oriented as possible. The orientation of the 
work machine, with respect to the trench and existing structures is 
adjusted by the machine operator utilizing machine stabilizing structures. 
The level position is determined from experience and practice and is 
generally a rough estimate of an actual level condition of the 
machines'digging assembly. 
The subject level indicating mechanism offers a solution to the above noted 
problems and takes the guess work out of leveling the work machine prior 
to the digging operation.

BEST MODE FOR CARRYING OUT THE INVENTION 
With reference to the drawings, a work machine 10 for performing a variety 
of work functions includes a frame structure 12, an engine 14 for 
providing power to the work machine 10, an operator's compartment 16 which 
is supported on the frame structure 12, and a digging assembly 18 which is 
supported on the frame structure 12 and is connected to the rear portion 
20 of the work machine 10. The work machine 10 further includes front 
wheels 22 and rear wheels 24 for supporting and propelling the work 
machine 10. The work machine 10 if of a type commonly referred to as a 
backhoe loader and further includes a loader bucket assembly 26 which is 
pivotally connected at 28 to the frame structure 12 at the front portion 
30 of the machine 10. 
The digging assembly 18 includes a stabilizing apparatus 32, a swing frame 
or bracket 34, a boom member 36, a stick member 38, and a digging bucket 
40. The stabilizing apparatus 32 includes first and second stabilizing 
arms 42,44 and respective first and second fluid powered cylinders 46,48 
connected between the swing frame 34 and the respective stabilizing arms 
42,44. The stabilizing apparatus 32 is adapted to stabilize the work 
machine 10 during a digging operation and also serves to tilt the machine 
10 and digging assembly 18 relative to a vertical plane 50 which is normal 
to the ground surface 52 which supports the work machine 10. 
A level indicating mechanism 54 which is removably positioned on the work 
machine 10 includes a magnet 56, a level instrument 58 positioned within 
the magnet 56, and a potting material 60, such as an epoxy, adapted to 
surround the level instrument 58 and secure it to the magnet 56. The level 
instrument 58 includes a bullseye level 62. The level indicating mechanism 
54 is adapted to indicate the relative level position of the work machine 
10, and the digging assembly 18, with respect to the ground surface 52 
which supports the work machine 10. The level indicating mechanism 54 is 
preferably removably connected to the machine frame 12, where it is easily 
visible to the operator of the digging assembly 18 during a digging 
operation. Since the level indicating mechanism 54 is held to the frame 12 
by the magnet 56, it can easily be removed and connected to other metal 
portions of the work machine 10. Although a circular ring magnet 56 is 
shown, other types of magnets, such as strip magnets, could be used to 
hold the level 62 to the machine frame 12. 
Industrial Applicability 
With reference to the drawings, and to the previous detailed description, 
the subject level indicating mechanism 54 is particularly useful with 
excavating type work machines, such as a backhoe loader machine 10. Such 
work machines 10 are utilized to excavate trenches for burying pipelines 
and utilities, as well as excavating and uncovering previously buried 
materials. When working in close proximity to buildings or other 
structures, or adjacent other buried cables or pipes, it is extremely 
important that the excavated trench be as straight vertically as possible. 
The subject level indicating mechanism 54 provides the operator of the 
work machine 10 with the information he needs to dig such a trench. 
When the work machine 10 and digging assembly 18 have been positioned to 
begin an excavation, the machine operator places the level indicating 
mechanism 54 on the swing frame 34 where it is held by the circular ring 
magnet 56. The machine operator can then adjust the machine 10 and the 
digging assembly 18, with respect to the ground surface 52 and the 
vertical plane 50, by operating the first and second cylinders 46,48 to 
extend or retract the first and second stabilizing arms 42,44 to bring the 
machine 10 to a level position, as indicated by the level instrument 58. 
The operator then performs the digging operation, and the level indicating 
apparatus can be removed and stored inside the operator's compartment, or 
on other locations of the work machine 10. 
Other aspects, objects, and advantages of this invention can be obtained 
from a study of the drawings, the disclosure, and the appended claims.