Land vehicles – Wheeled – Running gear
Reexamination Certificate
2000-01-25
2001-11-27
Dickson, Paul N. (Department: 3618)
Land vehicles
Wheeled
Running gear
C180S311000, C212S247000, C212S253000, C414S687000
Reexamination Certificate
active
06322104
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an undercarriage frame structure for an excavator or power shovel that provides proper support for a bearing and ring gear of an excavator upper structure without machining the frame, resulting in reduced manufacturing costs. The frame is used for supporting additional components for mounting the tracks that propel the excavator, and auxiliary equipment such as a backfill blade.
In the prior art, mini excavators or small power shovels are widely used. These are track propelled vehicles that have an undercarriage mounting the track and accessory items, and including a frame with a horizontal surface on which a bearing and ring gear that supports a rotatable turntable plate is mounted. The turntable mounts a cab and operator's platform, as well as the excavator bucket. The existing undercarriage frame that mount the bearing and a ring gear typically is a very thick or heavy plate that has a machined surface on which the bearing support is mounted, in order to obtain a surface that is flat and perpendicular to the vertical axis of rotation. The plate is large and heavy, making it difficult to handle and time consuming to machine, which increases the manufacturing costs. Since the bearing support ring is quite heavy as well, any portion of the surface on the heavy plate that is out of true will cause the bearing to be inaccurately located.
Various types of frames have been advanced, but the need for machining has been a source of extra cost for years.
SUMMARY OF THE INVENTION
The present invention relates to an undercarriage for an excavator which supports a rotatable upper plate mounting a platform and a working implement, such as an excavator bucket, and provides a support for drive and propelling structure for the excavator. The undercarriage includes a frame having a support plate for supporting a swing bearing and ring gear used for mounting the upper plate and the excavator bucket, without machining subsequent to welding the frame together.
The frame is made up of two frame sections having flat top plates with integral depending skirts on the sides thereof. The plates and skirts will nest together, so that the plates that support the bearing are contiguous. The skirts of the plates are then welded together without any welding in the center plate portions of the frame sections. This minimizes any distortion of the plates, and leaves the center portions flat for mounting the bearing, including the ring gear.
To insure conformance of the top plates and to clamp the ring gear tightly, a reinforcing or backing ring is preferably placed on the bottom side of the top plates and the ring gear bearing bolts passed through the ring. The reinforcing ring, when needed, provides a flattening action on the bottom one of the frame plates and holds the lower plate planar.
Components for supporting the tracks and accessories such as a backfill blade can be mounted onto the frame without causing distortions in the plates. When the bearing and ring gear are bolted in place, the two plates, which have lower individual bending strength in the center portions than the present unitary thick plate, will permit slight shifting to conform to the bearing base without distorting the bearing so that the bearing will be held positively, and true without machining the upper surface of the frame.
The frame assembly or welding is made of two formed frame sections, each comprising a rolled steel plate and integrally die formed depending skirts. The frame sections can be formed quite precisely, and when welded together along the skirts, and the corners (but not on the flat plates forming the center) the frame sections will be securely held as an assembly without inducing unnecessary welding stresses and consequent distortions into the support area for the bearing and ring gear. The skirts of the frame sections also are welded to a bottom plate that forms a box section for rigidity. Cross tubes or sockets for holding the track supports are welded in the lower sides of the frame section skirts and also added rigidity.
The track supports of the present device are slidably mounted in cross tubes on the frame assembly. The track supports will telescope for changing the width or tread of the tracks. A hydraulic cylinder is mounted between the tubes on the frame and extends laterally so when operated it will move the tracks laterally in or out as desired.
REFERENCES:
patent: 4361242 (1982-11-01), Dion et al.
patent: 4391341 (1983-07-01), Taghon
patent: 4397481 (1983-08-01), Dion et al.
patent: 4596508 (1986-06-01), Kishi et al.
patent: 4622860 (1986-11-01), Cametti et al.
patent: 1 033 448 A3 (2000-12-01), None
patent: 2467759 (1981-04-01), None
patent: 05/179675 (1993-07-01), None
patent: 08/004053 (1996-01-01), None
patent: 10/266263 (1998-10-01), None
patent: 11/278300 (1999-10-01), None
Brochure on the 300 C-Series Excavators by Melroe Company, printed 10/97.
Bleth Jay J.
Duppong Gerald J.
Schatz Warren M.
Zander Stacey A.
Clark Equipment Company
Dickson Paul N.
Westman Champlin & Kelly P.A.
LandOfFree
Excavator frame and method of assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Excavator frame and method of assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Excavator frame and method of assembly will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2600855