Track Guide Or Alignment Mechanism Patents (Class 305/116)
  • Patent number: 11173971
    Abstract: Track systems for traction of a vehicle in which a spacing of laterally-adjacent ones of the track systems in a widthwise direction of the vehicle is adjustable. This may facilitate use of the vehicle in different conditions (e.g., in different field configurations, such as in different configurations of row crops, where the vehicle is an agricultural vehicle). For instance, the spacing of the laterally-adjacent ones of the track systems may be adjustable while the laterally-adjacent ones of the track systems are connected to a power train of the vehicle and/or without requiring use of additional parts (e.g. spacers).
    Type: Grant
    Filed: February 8, 2017
    Date of Patent: November 16, 2021
    Assignee: CAMSO INC.
    Inventors: Dewaine Kautsch, Jonathan Lauzier, Michel Deslauriers
  • Patent number: 9457852
    Abstract: A cartridge assembly for a track chain is disclosed. The cartridge assembly includes a pin that has a lubricant channel therein. The pin is accommodated in an inner bushing that also has a channel extending therethrough for accommodating the pin. The pin extends beyond either end of the inner bushing. The pin and inner bushing are partially disposed in an outer bushing that also has a channel for accommodating the pin in inner bushing. The ends of the inner bushing and pin extend beyond the ends of the outer bushing. First and second inserts are disposed at either end of the inner bushing. The first and second inserts are disposed between the outer bushing and a pair of opposing collars which are disposed on the ends of the pin beyond the inserts and beyond the ends of the inner bushing. The inserts and collars each include seals. The seals of the collars are supported by one or more thrust rings as opposed to the inserts or partially by the inserts.
    Type: Grant
    Filed: April 2, 2014
    Date of Patent: October 4, 2016
    Assignee: Caterpillar Inc.
    Inventors: Eric Johannsen, Roger Recker, Jason Sebright, Mark S. Diekevers
  • Publication number: 20150130268
    Abstract: A crawler mechanism includes a frame, a track including a plurality of shoes coupled together and supported for movement relative to the frame along a direction of travel, a sprocket, and a guide rail. The frame includes a first end, a second end, a first side extending between the first end and the second end and proximate a support surface, and a second side. Each shoe includes an intermediate portion having a first hardness. The sprocket drives the plurality of shoes to move along the second side of the frame. The guide rail is coupled to the second side of the frame and includes a base having an outer surface and a coating bonded to the outer surface. The coating contacts the intermediate portion of the shoes as the shoes move along the second side of the frame, and the coating defines a second hardness less than the first hardness.
    Type: Application
    Filed: November 11, 2014
    Publication date: May 14, 2015
    Inventors: Adam Scheuerman, Joseph Brenny
  • Publication number: 20130199859
    Abstract: A crawler device includes a wheel support, wheels respectively rotatably supported thereto, and a crawler belt run around the wheels. Each of the wheels includes a rigid wheel body and an elastic material exterior part fixed to an outer periphery of the wheel body. Raised portions are formed in an outer periphery of the exterior part to continuously extend in a width direction and be arranged in a circumferential direction spaced from each other. Drain grooves extending through the exterior part in the width direction are formed between the raised portions. Top surfaces of the raised portions of the exterior part surface contact an inner peripheral surface of the crawler belt with a frictional force working therebetween. Restriction members stopping opposite side edges of the crawler belt are provided in the wheel support to restrict the crawler belt from being displaced with respect to the wheels in the width direction.
    Type: Application
    Filed: September 15, 2011
    Publication date: August 8, 2013
    Applicant: TOPY KOGYO KABUSHIKI KAISHA
    Inventors: Tomoya Inoue, Shingo Tsukui, Katsuki Fujimoto
  • Patent number: 8494727
    Abstract: In order to achieve a solution which assists a farmer in working land in a way which reduces the risk of soil compaction of the land there is, among others, a method of determining a work trajectory to be followed by an agricultural work vehicle. The method includes accessing a soil carry capacity map of an area of land to be worked by the agricultural work vehicle, receiving load data of the agricultural work vehicle so as to determine the agricultural work vehicle load and determining the work trajectory to be followed by the agricultural work vehicle. The work trajectory is determined by correlating the soil carry capacity map and the load data of the agricultural work vehicle, so as to optimize that the area to be worked with low carry capacity is worked with low agricultural work vehicle load.
    Type: Grant
    Filed: November 23, 2010
    Date of Patent: July 23, 2013
    Assignee: Aarhus Universitet
    Inventors: Ole Green, Dionysios D. Bochtis
  • Publication number: 20110037311
    Abstract: A method and apparatus is disclosed, for construction and operation of an all terrain polymorphic tracked vehicle. The invention improves on the prior art by providing a mechanism whereby it is possible to vary the shapes of the tracks during operation of the vehicle. This capability facilitates negotiating obstacles and rough terrain, enables such vehicles to climb stairs or similar obstacles, and also enables self leveling of the vehicle on inclined terrain.
    Type: Application
    Filed: August 13, 2009
    Publication date: February 17, 2011
    Inventors: Rustam Stolkin, Mathew Hochberger, Kirk Deligiannis, Colin Finley Harrier
  • Publication number: 20100156169
    Abstract: An idler of an undercarriage assembly for a track-type machine is disclosed. The undercarriage assembly may have at least two links, which may be interconnected by a cartridge. The cartridge may have a bushing disposed about and rotatable relative to a pin. At least one of the links may have a link rail wear surface, which may be positioned an original wear surface height from the bushing. The idler may have a lower surface, which may be configured to wear against the link rail wear surface. The idler may also have an upper surface, which may be configured to wear against the bushing. The upper surface may be positioned radially outward of the lower surface by an original upper surface height. The original upper surface height may be between approximately 70% and approximately 90% of the original wear surface height.
    Type: Application
    Filed: December 4, 2009
    Publication date: June 24, 2010
    Applicant: Caterpillar Inc.
    Inventors: Daniel D. Angot, Roger E. Lawson
  • Publication number: 20090278403
    Abstract: A track unit for moving a ground work vehicle, comprising two elastic elements proximate to the front and rear ends, interposed between a monolithic upper portion of the structure that supports the driving wheel and a monolithic lower portion that supports two pairs of coaxial guiding wheels with parallel axles and resting rollers, means adapted to ensure a coplanar arrangement of the upper and lower portions of the structure being also provided.
    Type: Application
    Filed: May 26, 2009
    Publication date: November 12, 2009
    Inventor: Riccardo Canossa
  • Publication number: 20090212623
    Abstract: A traction system for a vehicle has a support frame that defines a circular track belt support that is revolvable about an axis at its center, a flexible track belt; and a track belt stretching assembly comprising one or more track belt stretching rollers. The system has one traction configuration in which the flexible traction belt is held on said support track forming a substantially circular, wheel-like traction surface, and can change to a stretching state in which said rollers engage said belt and stretch it from its state in said one traction configuration to a stretched state to define one or more other traction configurations of the system.
    Type: Application
    Filed: May 4, 2009
    Publication date: August 27, 2009
    Applicant: GALILEO MOBILITY INSTRUMENTS LTD.
    Inventors: Yuval Spector, Dan Raz, Avishay Novoplanski, Gregory Rinberg
  • Patent number: 7575289
    Abstract: A rubber crawler running device which includes a drive wheel connected to a drive shaft of a vehicle body, an idler wheel, and a rubber crawler having rubber projections formed on an inner peripheral surface thereof at predetermined intervals, the drive wheel and the idler wheel being disposed substantially horizontally, the rubber crawler being wound around the drive wheel and the idler wheel and contacting the running surface, wherein the drive wheel is formed so that engaging teeth thereof which engage with the rubber projections are exposed at right and left sides, and further comprising a guide skirt body fixed to the vehicle body and disposed at transverse direction outer sides of the drive wheel at a portion at which the rubber crawler is wound around the drive wheel, with a gap being kept between the drive wheel and the guide skirt body.
    Type: Grant
    Filed: April 18, 2003
    Date of Patent: August 18, 2009
    Assignee: Bridgestone Corporation
    Inventors: Shingo Sugihara, Hitoshi Akiyama
  • Publication number: 20090200091
    Abstract: A crawler has a track connection system. The crawler includes a crawler frame; at least one drive tumbler supported on the frame; a track made of a plurality of track shoes connected in series to produce a track having a first end and second end that can be connected together to form the track into an endless track. The track is wrapped around the frame, with the first and second ends spaced apart but each adjacent a section of the frame. The track connection system is mounted to the frame and includes a mover device connected to the frame; and a track engagement member coupled between the mover device and the track; iii) whereby actuation of the mover device causes the track engagement member to move the track into a position where the first and second ends can be connected.
    Type: Application
    Filed: February 9, 2009
    Publication date: August 13, 2009
    Inventors: Kenneth J. Porubcansky, Joel D. Zick
  • Patent number: 7267189
    Abstract: The invention relates to an undercarriage, preferably for a crawler-mounted crane, comprising a crawler track which runs on a crawler carrier and which consists of base plates articulatedly connected to one another, with cams being formed on the base plates which laterally center the crawler track under the rollers, wherein two metal guide sheets which extend substantially over the length of the crawler carrier and which are engaged behind by holding plates arranged at the base plates of the crawler tracks are laterally arranged at the lower carriage of the crawler carrier.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: September 11, 2007
    Assignee: Liebherr-Werk Ehingen GmbH
    Inventor: Hans-Dieter Willim
  • Patent number: 7100715
    Abstract: An idler guide unit for crawler type traveling apparatuses which attains the facilitation of clearance regulating operations and the reduction, which is owing to the facilitation of the mentioned operations, of traveling noise. This idler guide unit is formed so that the clearance regulating operations are carried out by using tapering blocks 26, position regulators 41, 50 for the tapering blocks 26 being also provided.
    Type: Grant
    Filed: November 18, 2003
    Date of Patent: September 5, 2006
    Assignee: Komatsu Ltd.
    Inventors: Masayuki Mukaino, Ken Law
  • Publication number: 20040065487
    Abstract: A track vehicle employing a rail track system attached to the sides of the frame of a track vehicle having a continuous track driven by pneumatic tires mounted to the frame proximate each end of the rail system along such that triangular torsion and compression links are mounted to the continuous track such that the apex end slides along the rail and the other ends extending against the track to provides lighter more even ground contact for use on snow and other soft terrain than present track vehicles.
    Type: Application
    Filed: October 7, 2003
    Publication date: April 8, 2004
    Applicant: Tool Engineering & Manufacturing Company
    Inventor: Paul G. McKinnon
  • Patent number: 6702406
    Abstract: A travel gear of a crawler work vehicle has a plurality of double bogie type track wheel devices. The double bogie type track wheel devices respectively include a first arm member attached to the lower part of a track frame so as to be swingable in the vertical direction, a second arm member whose almost center portion in the longitudinal direction is rotatably attached to the tip of the first arm member, and a pair of front and rear track wheels rotatably attached to front and rear ends of the second arm member and rolling on the tread of a crawler. A pair of first guard devices for preventing intrusion of a foreign matter into a space between the pair of front and rear track wheels and the crawler are attached to both side faces in the width direction of the vehicle of the first arm member.
    Type: Grant
    Filed: May 31, 2002
    Date of Patent: March 9, 2004
    Assignee: Komatsu Ltd.
    Inventors: Tsuyoshi Yoshida, Kazuyuki Onohara
  • Patent number: 6655757
    Abstract: A head sprocket assembly and sprocketless tail roller assembly for a pontoon track drive system wherein the sprocket assembly and tail roller is fitted with a plurality of support rings for straightening the track's elongated cleats attached to a plurality of chains passing lengthwise around the pontoons.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: December 2, 2003
    Inventor: Larry Prestenbach
  • Patent number: 6520602
    Abstract: A guide for a multi-link endless chain of a track-type undercarriage, especially for cranes, has an undercarriage support, at least one drive sprocket wheel provided with chain teeth, possibly an idler, and several track rollers. Each chain link of the endless chain has two guide webs which are symmetric to the center, spaced a certain distance apart, and extend in the travel direction. The webs have engaging surfaces which ride on opposed circumferential flanges on the drive sprocket wheel. A cog connects the two webs below the engaging surfaces and meshes with the chain teeth of the drive sprocket wheel. The guide has two parallel rails oriented in the travel direction of the endless chain, the inside surfaces of the rails coming to rest against the outside surfaces of the associated guide webs when the guide function is occurring.
    Type: Grant
    Filed: May 25, 2001
    Date of Patent: February 18, 2003
    Assignee: Demag Mobile Cranes GmbH
    Inventors: Werner Rutz, Ingo Nöske
  • Patent number: 6435628
    Abstract: A guiding arrangement has a guide structure having an opening defined therein. The guiding arrangement also has a roller assembly. The guiding arrangement further has an axle positioned relative to the guide structure so that a portion of the axle is located within the opening.
    Type: Grant
    Filed: August 24, 2000
    Date of Patent: August 20, 2002
    Assignee: Caterpillar Inc.
    Inventors: Michael D. Hasselbusch, Roy L. Maguire, Darby R. Robertson
  • Patent number: 6401847
    Abstract: This invention includes an undercarriage support and adjustment system for a tracked vehicle having first and second elongated outwardly extending members coupled to the vehicle, a first undercarriage bearing support coupled to the vehicle between the first and second outwardly extending members, and an undercarriage bearing support member slidingly coupled to the outer ends of the two support members and having a second undercarriage bearing support.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: June 11, 2002
    Assignee: Case Corporation
    Inventor: Thomas G. Lykken
  • Patent number: 6386653
    Abstract: Track laying work machines (10) are provided with a pair of track roller assemblies (20) positioned on opposite sides of the work machine (10). Each track roller assembly (20) includes a track (12) entrained around a drive wheel (14), an idler wheel (16), and a plurality of supporting mid-rollers (18). An apparatus for measuring misalignment and realigning (48) the track (12) is utilized to monitor alignment and align the track (12) during operation of the work machine (10).
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: May 14, 2002
    Assignee: Caterpillar Paving Products Inc.
    Inventor: Steven J. Brandenburger
  • Patent number: 6364437
    Abstract: The device comprises at least one track (10) formed from an endless flexible belt (22) fitted on the inside with at least one row of studs (24) situated in the longitudinal direction of the endless belt and spaced at a constant distance apart and each delimited by two transverse faces and two lateral faces, two main wheels (12, 16) and support wheels (20A, 20B, 20C) on which the endless belt rolls, and a guidance element (50) placed between a main wheel (12) and an adjacent support wheel (20C) and comprising rollers (52) able to frame the lateral faces of the studs (24) in order to ensure guidance and stabilization of the endless belt in the region of the guidance element.
    Type: Grant
    Filed: May 23, 2000
    Date of Patent: April 2, 2002
    Assignee: Otico
    Inventor: Olivier Phely
  • Publication number: 20010054844
    Abstract: A guide for a multi-link endless chain of a track-type undercarriage, especially for cranes, has an undercarriage support, at least one drive sprocket wheel provided with chain teeth, possibly an idler, and several track rollers. Each chain link of the endless chain has two guide webs which are symmetric to the center, spaced a certain distance apart, and extend in the travel direction. The webs have engaging surfaces which ride on opposed circumferential flanges on the drive sprocket wheel. A cog connects the two webs below the engaging surfaces and meshes with the chain teeth of the drive sprocket wheel. The guide has two parallel rails oriented in the travel direction of the endless chain, the inside surfaces of the rails coming to rest against the outside surfaces of the associated guide webs when the guide function is occurring.
    Type: Application
    Filed: May 25, 2001
    Publication date: December 27, 2001
    Applicant: Demag Mobile Cranes GmbH
    Inventors: Werner Rutz, Ingo Noske
  • Patent number: 6283241
    Abstract: A number of embodiments of snowmobile suspensions for the drive belt of the snowmobile. The suspension includes a single cushioning unit that has its opposite ends loaded by a linkage system that is interposed between a guide rail and a frame of the snowmobile. At least one of these pivotal connections is adjustable, and the adjustment is provided in a manner so that it can be made without changing the effective length of the cushioning unit during adjustment. In addition, a number of the embodiments permit the adjustment to be made at one side of the snowmobile.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: September 4, 2001
    Assignee: Yamaha Hatsudoki Kabushiki Kaisha
    Inventor: Takahiko Kubota
  • Patent number: 6273530
    Abstract: The adjustment mechanism of the present invention is mounted to a frame and comprises an alignment cam that is pivotally mounted to the frame by a tension link pivot pin. The alignment cam is provided with an actuating arm that is coupled to a longitudinally extendible adjusting member. The longitudinally extendible adjusting member comprising a screw jack. A tension link is pivotally mounted to the tension link pivot pin. Camming surfaces on the alignment cam are skewed with respect to the transverse axis defined by the tension link pivot pin so that rotation of the alignment cam twists the tension link and thereby the idler wheel predominately about a vertical axis. Albeit to a lesser degree, rotation of the alignment cam also twists the tension link and idler about a longitudinally extending horizontal axis. Therefore by extending or retracting the screw jack, the toe-in/toe-out orientation of the idler wheel can be adjusted.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: August 14, 2001
    Assignee: Deere & Company
    Inventors: Gary Dean Johnson, Robert James White, Bradley Thomas Cote
  • Patent number: 6267459
    Abstract: Endless track laying work machines are provided with a pair of track roller assemblies positioned on opposite sides of the work machine. Each track roller assembly includes an endless rubber belt entrained around a drive wheel, an idler wheel, and a plurality of supporting mid-rollers. An automatic belt alignment system is utilized to align the endless rubber belt during operation of the endless track laying work machine (10). The automatic belt alignment system also provides connection of the idler wheel assembly to a tensioning system and to the forwardly extending nose portion of a track roller frame.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: July 31, 2001
    Assignee: Caterpillar Inc.
    Inventors: Dan J. Becker, Daniel M. Keehner
  • Patent number: 6095531
    Abstract: An improved hand truck apparatus for use in moving loads up and down stair which includes a pair of novel stair tread engaging assemblies which operate smoothly and in a relatively friction-free manner. The stair engaging belts of each of the stair tread engaging assemblies is supported by a plurality of freely rotating, spaced-apart rollers which are grooved to closely receive and support the lower portion of the belts in the manner to positively guide the belts around the belt supporting frames of the assemblies as the rollers freely rotate about their individual axles. The roller supporting frame of each of the stair tread engaging assemblies is uniquely provided with guide means for guiding the stair tread engaging belts into the channels formed in the rollers and for preventing undesirable frictional contact between the belt and the supporting frame as the belt travels about the supporting rollers.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: August 1, 2000
    Assignee: Olympia industrial, Inc.
    Inventor: Zareh Khachatoorian
  • Patent number: 6074023
    Abstract: A guide roller assembly for use in a guide roller mechanism of a crawler type vehicle, including a support shaft fixedly provided on a truck frame and a guide roller rotatably mounted on the support shaft through bearings. The guide roller has an integral unitary body structure of a stepped cylindrical shape having a radially bulged portion formed integrally by plastic deformation in an axially intermediate portion between cylindrical end portions of a smaller diameter, and having a uniform wall thickness over the entire length of the guide roller. The guide roller is improved in strength and can realize a substantial cut in production cost.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: June 13, 2000
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Fujio Satou, Ken Ichiryu, Kiyoshi Tanaka
  • Patent number: 6033043
    Abstract: This invention is to suppress repeated striking noises as generated by a crawler belt (29) when taken up onto a drive sprocket (25) in a polygonally bent shape. A crawler belt support block (34) is fixedly mounted on top of an upper reinforcing plate (19) of a bracket (15) on the side of the drive sprocket. The crawler belt support block (34) includes a skid block (36) with a crawler belt sliding surface (36B) to be held in sliding contact with lower surfaces of respective links (30) of the crawler belt (29) to guide same in a direction tangential of the drive sprocket (25) when the crawler belt (29) is taken up onto the drive sprocket (25). The crawler belt support block suppresses vertical movements as would occur to the crawler belt (29) when taken up onto the drive sprocket (25) in a polygonally bent shape, to reduce the repeated striking noises generated by meshing engagement of bushes (32) of the crawler belt (29) and the drive sprocket (25).
    Type: Grant
    Filed: July 14, 1997
    Date of Patent: March 7, 2000
    Assignee: Hitachi Construction Machinery Co., Ltd.
    Inventors: Takeshi Higuchi, Hiroyuki Nishimori
  • Patent number: 5927412
    Abstract: Track sub-assembly having a castering swing link for supporting a primary idler spindle, the swing link having an upper bore for accepting a first connecting pin and a lower bore for accepting a second connecting pin to define a pivot line, and an offset idler bore offset from the pivot line permitting castering of the primary idler in response to externally imposed force vectors, with self-alignment of the primary idler to its proper tracking position.
    Type: Grant
    Filed: January 14, 1997
    Date of Patent: July 27, 1999
    Assignee: Caterpillar Inc.
    Inventor: Elmer R. Crabb
  • Patent number: 5829545
    Abstract: A snowmobile having a crawler belt operatively connected to a drive wheel, slide rails and guide wheels supported by the slide rails, the slide rails including a main slide rail arranged at approximately a midportion of the crawler belt, and a pair of right and left side slide rails arranged along outside side edges of the crawler belt, the guide wheels being arranged between the main slide rail and the side slide rails.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 3, 1998
    Assignee: Honda Giken Kogyo Kabushiki Kaisha
    Inventors: Kazuhiro Yamamoto, Takao Kouchi, Shizuo Kawano, Tadaaki Nagata, Hideaki Suzuki
  • Patent number: 5821974
    Abstract: Of a plurality of page memories for storing printing data corresponding to the printing heads, at least the page memory is associated with an auxiliary memory for storing at least two continuous pages of printing data for at least one printing head, wherein a printing data write unit executes a process for writing the next page of printing data in one of the page memory and the auxiliary memory while the printing data stored in the other one of the page memory and the auxiliary memory is being printed, and the image processing unit supplies printing data continuously and alternately from the page memory and the auxiliary memory to each corresponding printing head.
    Type: Grant
    Filed: September 27, 1996
    Date of Patent: October 13, 1998
    Assignee: Kabushiki Kaisha TEC
    Inventors: Kaname Iga, Hidemi Mihara, Takashi Ichikawa, Kazuhiro Fushimi
  • Patent number: 5791257
    Abstract: An overhead crane adapted to be supported on a pair of spaced apart, generally parallel first and second rails, the crane having a frame having opposite first and second ends, a first wheel rotatably mounted on the first end of the frame, the first wheel being adapted to roll along the first rail, a second wheel rotatably mounted on the second end of the frame, the second wheel being adapted to roll along the second rail, a first bearing assembly supporting the first wheel, a second bearing assembly supporting the second wheel, each of the first and second bearing assemblies including a bearing supporting the associated wheel for rotation relative to the frame about a rotation axis, the rotation axis having a position relative to the frame, and a mechanism connecting the bearing to the frame and allowing the bearing to be fixed in various positions relative to the frame, a hoist supported by the frame, and a load engaging mechanism which is raised and lowered by the hoist.
    Type: Grant
    Filed: January 8, 1997
    Date of Patent: August 11, 1998
    Assignee: Harnischfeger Corporation
    Inventor: Jeffrey A. Konop
  • Patent number: 5671819
    Abstract: An improved tire tensioning system for use with flexible band tracks moun on dual tire sets is disclosed. The tensioning system includes first and second tensioning bars which each have one threaded end connected to a turnbuckle and a second end connected to block fixed to a respective front or rear wheel axle by a ball coupling. Also shown is an improved axle structure which can be used to adjust the toe in/out of the rear tire sets.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: September 30, 1997
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: Donald H. Kendall
  • Patent number: 5639148
    Abstract: An adjustment mechanism for providing fine adjustments of the relative position of the first wheel relative to the other wheel or wheels in a belted track system. The adjustment mechanism comprises a screw jack assembly that is mounted to the first and second flanges of a first longitudinal member and a second longitudinal member, respectively. After loosening the fastening bolts for the two flanges, the screw jack can be manipulated rotating the first longitudinal member relative to the second longitudinal member. After the correct adjustment position has been found, the fastening bolts can be retightened.
    Type: Grant
    Filed: April 17, 1996
    Date of Patent: June 17, 1997
    Assignee: Deere & Company
    Inventor: Alan David Sheidler