Image Forming Component Patents (Class 399/31)
  • Publication number: 20030235417
    Abstract: A test measurement of the universal hardness is carried for a fixing belt (20) formed by sequentially coating an elastic layer (22) and a separation layer onto a base element (21), in which case, the universal hardness is determined for each of indentation depths of 1 &mgr;m and 4 &mgr;m from the surface side of the separation layer (23). The fixing belt (20) can be regarded as a standard product, when the universal hardness HU for the indentation depth of 1 &mgr;m satisfies the relation, HU≦30 [N/mm2], and, at the same time, when the universal hardness HU for the indentation depth of 4 &mgr;m satisfies the relation, HU≦12 [N/mm2].
    Type: Application
    Filed: March 24, 2003
    Publication date: December 25, 2003
    Inventors: Norihiko Aze, Kyoichi Ashikawa, Kohji Kamiya, Minoru Matsuo
  • Patent number: 6633732
    Abstract: The present invention relates to providing supplemental counts or “clicks” to account for recovery conditions in a document processing system. The application of recovery counts combined with the system cycle count when suitably summed will provide superior measure of the wear for a replaceable element as well as improved indication for the determination of the end of life of a replaceable element in that system. In this manner the more timely service or substitution for that replaceable element in the system can be provided, thereby allowing costs and service down-time to be minimized.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: October 14, 2003
    Assignee: Xerox Corporation
    Inventors: Robert P Siegel, Tracy E. Thieret
  • Publication number: 20030170038
    Abstract: An image forming apparatus has a unit in which at least an expendable component is incorporated. The unit is reusable by periodically replacing the expendable component. Indication means for indicating a record on use of the unit is attached to a given position on the unit.
    Type: Application
    Filed: March 5, 2003
    Publication date: September 11, 2003
    Applicant: Kyocera Mita Corporation
    Inventors: Yukihiro Ito, Satoru Yonemoto, Hideki Kitagawa
  • Patent number: 6594451
    Abstract: A use situation reporting system reports the use situations of a developer and other consumables included in an image forming apparatus for forming images on a recording material. More particularly, the use situation reporting system reports an amount of remaining developer and the use times of consumables to a user. Thus, the timing of replacing a cartridge with a new one can be concisely reported to the user.
    Type: Grant
    Filed: December 8, 2000
    Date of Patent: July 15, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomomi Kakeshita, Hiroshi Sasame, Hiroaki Ogata, Shinya Yamamoto
  • Patent number: 6580880
    Abstract: A logic and control unit (LCU) is configured to assess the viability of various subsystems in the electrophotographic marking process. The LCU determines a charging efficiency between a primary charger and a photoconductor, establishes a reference voltage on the photoconductor, wherein the reference voltage corresponds to the charging efficiency, operates a first subsystem in a non-print production mode to produce a first resulting voltage on the photoconductor, and translates the photoconductor to a stationary sensor for measuring the first resulting voltage.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: June 17, 2003
    Assignee: Heidelberger Druckmaschinen AG
    Inventors: Matthias Regelsberger, David E. Hockey, Edward M. Eck
  • Publication number: 20020141768
    Abstract: The present invention provides an image-forming machine having a photoconductor forming a surface and a toning station adjacent the surface. The toning station has at least one roller for supplying toner near the surface. Additionally, the image-forming machine has a replenisher station for supplying toner to the toning station. The replenisher station includes a moving part connected with the replenisher station, and a control device located near the moving part. The control device monitors the movement of the moving part and generates a timing signal in response. The present invention also provides a method for detecting toner clogging in a replenisher station for an image-forming machine. The method includes monitoring the movement of a moving part connected with the replenisher station, generating a timing signal in response to the movement of the moving part, and determining whether toner is clogged in the replenisher station based upon the timing signal.
    Type: Application
    Filed: March 28, 2001
    Publication date: October 3, 2002
    Applicant: Heidelberg Digital, L.L.C.
    Inventor: Kenneth P. Friedrich
  • Patent number: 6444379
    Abstract: There are provided a method for preparing a printed wiring board which can form electrostatic latent images at the desired positions of a substrate with good precision, and a uniform and good image can be formed for preparing a printed wiring board having circuits on the both surfaces of the substrate from a material to be developed having at least a metal conductive layer and a photoconductive layer on both surfaces of an insulating substrate in this order, and a preparation device.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: September 3, 2002
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Yasuo Kaneda, Masanori Takase, Kenji Hyodo
  • Patent number: 6420012
    Abstract: A toner carrier which carries a toner in the form of thin film on its surface, comes close to or comes into contact with the image-forming body so as to supply the toner to the surface of the image-forming body, thereby forming a visible image on the surface of the image-forming body, said toner carrier being characterized in that its conductive elastic layer has a coating layer thereon which is made of a material containing a resin with a glass transition point lower than 10° C. and has a dynamic elastic modulus (E′) of 107-109.8 dyn/cm2 and a loss tangent (tan &dgr;) smaller than 0.7. A toner carrier in which the electrically conductive elastic layer is formed from an elastic material having a tear strength greater than 10 kg/cm measured according to JIS K6252.
    Type: Grant
    Filed: July 20, 2000
    Date of Patent: July 16, 2002
    Assignee: Bridgestone Corporation
    Inventors: Koji Takagi, Toshiaki Arai, Takao Ohuchi, Tokuo Okada
  • Patent number: 6377758
    Abstract: A system is disclosed for detecting defects in a printed image to analyze imaging problems in an image reproducing apparatus. The printed image is scanned by the scanner and the printed image data obtained in the scanner is fed back and compared with original image data. The system finds defects in the printed image in a closed loop manner. The printed image data is automatically feeds back to a control unit so that a processor compares the printed image data with the original image data to detect defects in the intermediate imaging member. The system determine whether the intermediate imaging member needs to be replaced on the basis of the comparison.
    Type: Grant
    Filed: November 6, 2000
    Date of Patent: April 23, 2002
    Assignee: Xerox Corporation
    Inventors: William M. OuYang, Jack Whipple
  • Patent number: 6370340
    Abstract: A system for assessing the performance of an electrophotographic marking machine is provided, wherein data from several different inputs are gathered in two distinct sets having different frequencies. A high-frequency data set includes parameters typically recorded with each print made, and provide an electrophotographic history which is used in deducing the cause of malfunctions. The lower-frequency data are typically recorded at the time of each autosetup, and provide electrophotographic trend information which is used as a predictor of component and consumable lifetimes. In each data set, only data over an appropriately selected period maintained on a first-in, first-out basis. This system has the advantage of simultaneously providing an intensive recent history for tracing faults, and enabling long-term trends to be discerned without being buried in a redundant excess of data.
    Type: Grant
    Filed: May 17, 2000
    Date of Patent: April 9, 2002
    Assignee: Heidelberg Digital, L.L.C.
    Inventors: Matthias Regelsberger, David E. Hockey
  • Patent number: 6365307
    Abstract: An ionic medium, e.g., an ionic liquid, gel-like solid, etc., contacts a photoreceptor, e.g., as used in xerography etc., in order to charge and/or discharge the photoreceptor. A measuring device, e.g., an electrometer or current meter, measures at least one characteristic, e.g., voltage or current, and, if desired, light intensity, of the photoreceptor during or shortly after charging and/or discharging operations.
    Type: Grant
    Filed: December 12, 2000
    Date of Patent: April 2, 2002
    Assignee: Xerox Corporation
    Inventor: James M. Markovics
  • Patent number: 6336007
    Abstract: An evaluation method and printer in which a maintenance man may easily identify a deteriorated component in addition to a component that is broken down or is remarkably hard to operate without the need for any additional complex detecting device. A printer has a control part which controls a mechanical part and judges quantitatively in which state among normal, deteriorated, and abnormal states each mechanical part component is located. This judgment will change in accordance with whether the printer is in a maintenance or a normal mode. Further, a deteriorated component can be determined by visually inspecting a copy after one or a combination of electric parameters have been set to printable upper and lower limits.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: January 1, 2002
    Assignee: Fujitsu Limited
    Inventors: Eiichi Sugisaki, Hideo Okawa, Yoshinori Wada
  • Patent number: 6285837
    Abstract: In a xerographic development system in which an AC field is set up in a gap between a donor member and the photoreceptor to develop an electrostatic latent image, a series of tests are performed to ascertain that the width of the gap is within a suitable range. In test mode, various DC and AC biases associated with the field are systematically altered, and the reflectivities of resulting test images are read. Based on these reflectivity readings, it can be determined if the gap is too wide, such as to cause poor print quality, or too narrow, such as to cause arcing.
    Type: Grant
    Filed: September 25, 2000
    Date of Patent: September 4, 2001
    Assignee: Xerox Corporation
    Inventors: Roger W. Budnik, James M. Pacer, Scott L. Kauffman, Richard M. Maier, Michael G. Swales
  • Patent number: 6154619
    Abstract: An apparatus is provided for detecting the state of a consumable for a printer. The apparatus includes a consumable cartridge, a drive motor, a current measuring device, memory and processing circuitry. The consumable cartridge has a rotatable member that is carried by the cartridge. The motor is configured to rotate the rotatable member. The current measuring device is associated with the motor, and is operative to measure current flow through the motor. The memory is configured to store a predetermined value corresponding to current flow through the motor, and indicative of a change in state of the rotatable member. The processing circuitry is coupled with the current measuring device and the memory and is operative to determine when the measured current flow corresponds to the predetermined value of current flow. Furthermore, the processing circuitry identifies a state of the consumable cartridge. A method is also provided.
    Type: Grant
    Filed: October 27, 1999
    Date of Patent: November 28, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Darius Boockholdt, Quintin T. Phillips
  • Patent number: 6148157
    Abstract: An apparatus for developing a latent image recorded on a surface, including a housing defining a chamber storing a supply of developer material comprising toner; a toner donor member spaced from the surface and being adapted to transport toner to a region opposed from the surface; an electrode member spaced near the surface of a donor roll, said electrode member being electrically biased by a power supply to detach toner from said donor member as to form a toner cloud for developing the latent image; and a current signature analysis system, in communication with said power supply, for sampling an instant current signature being supplied to said electrode member; and a comparator, in communication with said current signature analysis system, for comparing said instant current signature to a plurality of preset fault signatures, said comparator including means for generating a message fault if the difference between said instant current signature to a plurality of preset fault signatures exceed a preset thresho
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: November 14, 2000
    Assignee: Xerox Corporation
    Inventor: William H. Wayman
  • Patent number: 6122460
    Abstract: An improved electrophotographic printer is provided in which the voltage applied to the charge roller is automatically adjusted to compensate for its changing characteristics over its life span. A high voltage DC power supply includes an output that is connected to the charge roller, and the input side of this high voltage DC power supply is controlled by a microprocessor of the print engine. The print engine controls the output voltage of the high voltage DC power supply by changing the duty cycle of the pulse-width modulated control signal that is supplied to the input of the high voltage DC power supply. A look-up table contains the correct duty cycle for the pulse-width modulated control signal with respect to the number of prints that have been made. The result of the inspection of the look-up table is used by the microprocessor of the print engine to control the correct duty cycle for the pulse-width modulated signal.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: September 19, 2000
    Assignee: Lexmark International, Inc.
    Inventors: Kermit Arnold Meece, Christopher David Strack, Troy Dustin Smith Tomson
  • Patent number: 6072970
    Abstract: A charge roller has a steel shaft and conductive outer cylindrical body which is formed by curing with heat a blend comprised of epichlorohydrin rubber, mineral-oil-free zinc oxide dispersion, stearic acid as a lubricant, accelerators and a sulfur donor. The roller has a long useful life and does not express oil while inactive.
    Type: Grant
    Filed: October 29, 1996
    Date of Patent: June 6, 2000
    Assignee: Lexmark International, Inc.
    Inventors: William Hargis Barton, Alan Stirling Campbell, Martin Victor DiGirolamo, Donald Wayne Stafford
  • Patent number: 6061543
    Abstract: An image forming apparatus has a transfer region located between a first belt and a second belt, which belts are respectively spanned and tensioned around a plurality of rollers. A total length of the first belt is substantially equal to integral multiples of a total length of the second belt. Certain portions of the belts are deformed via plastic deformation caused by contacting the plurality of rollers. The rollers are arranged so that deformed portions of the belts do not overlap each other in the transfer region.
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: May 9, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Shin Kayahara, Takashi Bisaiji
  • Patent number: 6023595
    Abstract: It is an object to identify a failed portion in a circuit for image processing and notify a service center of the failed portion, thereby enabling the failed circuit to be promptly replaced. Circuit portions of image processing units are constructed on separate substrates. As processing routes of an image signal which is inputted from an A/D converting unit, a route in which the image signal passes through a given circuit portion and a route in which the image signal doesn't pass therethrough are set. Data of a predetermined pattern is processed by those processing routes. The presence or absence of a failure of each circuit portion is discriminated from the processing results. The discrimination result is transmitted to an external apparatus installed in a service center.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: February 8, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Suzuki, Shinobu Arimoto, Nobuyuki Watanabe, Kazuhito Ohashi, Akiko Kanno, Hiroyuki Tsuji, Tetsuya Nakamura, Shingo Kitamura, Tsunao Honbo, Junichi Noguchi
  • Patent number: 5995775
    Abstract: A method to provide a highly intelligent, automated diagnostic system that identifies the need to replace specific parts to minimize machine downtime rather than require extensive service troubleshooting. In particular, a systematic, logical test analysis scheme to assess machine operation from a simple sensor system and to be able to pinpoint parts and components needing replacement is provided by a series of first level of tests by the control to monitor components for receiving a first level of data and by a series of second level of tests by the control to monitor components for receiving a second level of data. Each of the first level tests and first level data is capable of identifying a first level of part failure independent of any other test. Each of the second level tests and second level data is a combination of first level tests and first level data or a combination of a first level test and first level data and a third level test and third level data.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: November 30, 1999
    Assignee: Xerox Corporation
    Inventors: Roger W. Budnik, James M. Pacer, Guru B. Raj, Ralph A. Shoemaker, Michael G. Swales, Michael E. Beard
  • Patent number: 5946521
    Abstract: A method to provide a highly intelligent, automated diagnostic system that identifies the need to replace specific parts to minimize machine downtime rather than require extensive service troubleshooting. In particular, a systematic, logical test analysis scheme to assess machine operation from a simple sensor system and to be able to pinpoint parts and components needing replacement is provided by a series of first level of tests by the control to monitor components for receiving a first level of data and by a series of second level of tests by the control to monitor components for receiving a second level of data. Each of the first level tests and first level data is capable of identifying a first level of part failure independent of any other test. Each of the second level tests and second level data is a combination of first level tests and first level data or a combination of a first level test and first level data and a second level test and second level data.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: August 31, 1999
    Assignee: Xerox Corporation
    Inventors: Roger W. Budnik, James M. Pacer, Guru B. Raj, Ralph A. Shoemaker, Michael G. Swales
  • Patent number: 5937224
    Abstract: A method to provide a highly intelligent, automated diagnostic system that identifies the need to replace specific parts to minimize machine downtime rather than require extensive service troubleshooting. In particular, a systematic, logical test analysis scheme to assess machine operation from a simple sensor system and to be able to pinpoint parts and components needing replacement is provided by a series of first level of tests by the control to monitor components for receiving a first level of data and by a series of second level of tests by the control to monitor components for receiving a second level of data. Each of the first level tests and first level data is capable of identifying a first level of part failure independent of any other test. Each of the second level tests and second level data is a combination of first level tests and first level data or a combination of a first level test and first level data and a third level test and third level data.
    Type: Grant
    Filed: March 5, 1998
    Date of Patent: August 10, 1999
    Assignee: Xerox Corporation
    Inventors: Roger W. Budnik, Guru B. Raj, James M. Pacer, Michael G. Swales
  • Patent number: 5929640
    Abstract: An automated test system is provided for evaluating characteristics of photoreceptors used in the electrophotographic process. The test system includes a retainer for holding the photoreceptor, typically in the form of a cylinder or drum, high voltage power supplies, a charging device, light sources, and non-contact electrostatic surface potential probes, the entirety of the test system enclosed in a light-proof cabinet. A control unit responsive to user defined parameters automatically performs tests for drum substrate surface cleanliness, photoreceptor layer thickness, physical defects, and electrophotographic properties. Linear and circular scanning and fixed adaptable systems are shown.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: July 27, 1999
    Assignee: Quality Engineering Associates
    Inventors: Ming-Kai Tse, Michael H. Wollowitz, Peter F. Hays, David J. Forrest
  • Patent number: 5809365
    Abstract: The present invention provides an image forming apparatus for forming a toner image on a transfer material by using an intermediate transfer member, comprising an image bearing member, a toner image forming means for forming a toner image on the image bearing member, an intermediate transfer member moving along an endless path while contacting with the image bearing member, a measuring means for measuring a color of the intermediate transfer member, a judge means for judging a toner contaminated condition of the intermediate transfer member on the basis of a measured result by the measuring means, and a display means for displaying a judged result by the judge means. With this arrangement, by detecting the contamination of the intermediate transfer member and by displaying the contamination condition, both of deterioration of image quality due to toner contamination of the intermediate transfer member and reduction of a function for automatically setting an image forming condition can be prevented.
    Type: Grant
    Filed: August 6, 1997
    Date of Patent: September 15, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventor: Ryuichi Yoshizawa
  • Patent number: 5797060
    Abstract: An electrophotographic subsystem (130) with on-board monitoring and adjusting capabilities. The subsystem contains a photoreceptor, at least one toner dispenser, a light sensor and a processor. The processor monitors either light received from a light-imaging subsystem which is in the system into which the EP subsystem is inserted, the wear on the photoreceptor, or the toner's composition and amount, or all of the above processes. The processor then sends information either via controllers or directly to various subcomponents as operating parameter settings or instructions.
    Type: Grant
    Filed: November 5, 1996
    Date of Patent: August 18, 1998
    Assignees: Texas Instruments Incorporated, AGFA-Gevaert N.V.
    Inventor: E. Earle Thompson
  • Patent number: 5778277
    Abstract: A scanning system that accurately positions a moving carriage assembly in two directions relative to a platen. Such a scanning system includes a frame that has a registration member that extends in the Y direction, and a platen whose plane is normal to the Z direction and which is attached to the frame. The platen receives a substrate in a predetermined position relative to the registration member. The scanning system further includes a base that has a first and second tilted surfaces that extend in the Y direction, and a moving carriage assembly that is disposed between the platen and the base. The moving carriage assembly includes a housing, at least one button connected to the housing, and first and second biased pivot arms with first and second rollers that ride on the first and second tilted surfaces. The biased pivot arms push the housing against the tilted surfaces such that the button contacts the platen and the registration member.
    Type: Grant
    Filed: October 25, 1996
    Date of Patent: July 7, 1998
    Assignee: Xerox Corporation
    Inventors: Stephen J. Wenthe, Jr., Gordon B. Reid, Frederick B. Clark, Jack K. Fullerton
  • Patent number: 5771430
    Abstract: An image forming apparatus includes a photoreceptor drum having a toner image formed on its surface, a transfer drum having a dielectric layer, a semiconductive layer and a conductive layer arranged orderly, a power source section applying a predetermined voltage to the conductive layer, and a ground roller which is grounded and comes in contact with the surface of the dielectric layer through a transfer paper. In addition, in the image forming apparatus, a foaming body having elastic property is used for the semiconductive layer, and a diameter of foams in the semiconductive layer is controlled within the range of between 200 .mu.m and 400 .mu.m. Alternatively, the average micro-gap (which is obtained by equalization of a micro-gap formed between the semiconductive layer and the dielectric layer) may be controlled within the range of between 20 .mu.m and 50 .mu.m.
    Type: Grant
    Filed: January 30, 1997
    Date of Patent: June 23, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Yoshie Iwakura
  • Patent number: 5659855
    Abstract: An image forming apparatus uses an endless belt image member having a magnetic strip along one or more edges. A linear printhead is flashed in response to a magnetic encoder signal in the magnetic strip. Preferably, the apparatus has first and second linear writers and the magnetic encoding signal is created in the magnetic strip in conjunction with creation of a writing signal for the first writer with the second writer using the magnetic encoding signal to register its writing with the first writing. Preferably, an auxiliary signal is placed in the strip indicative of variable characteristics of either the image member or the image forming apparatus. This in turn is read by the apparatus and a charging, exposing or toning station controlled in response to the auxiliary signal.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: August 19, 1997
    Assignee: Eastman Kodak Company
    Inventors: Eric C. Stelter, Joseph A. Pavlisko
  • Patent number: 5659836
    Abstract: A predetermined sheet retaining plane C for absorbing a record sheet is provided in the circumferential surface of a sheet carrier, and a low-reflectivity area which is to be partially covered with the record sheet is provided at a leading portion of the sheet retaining plane C. Reflection photosensors for detecting the reflectivity of the sheet carrier including the low-reflectivity area are disposed around the sheet carrier. Whether a record sheet is held in the sheet retaining plane C is judged on the basis of detection signals of the photosensors.
    Type: Grant
    Filed: December 15, 1995
    Date of Patent: August 19, 1997
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Nobuo Hyakutake, Fumio Furusawa, Takashi Kawabata, Masaaki Tokunaga
  • Patent number: 5613047
    Abstract: According to the present invention, a concept of functional quantities indicative of quantified functional degrees of such lower-level functions as "clearer characters", "cleaner background", and "thicker characters", which are subordinating to a qualification-oriented function of "more beautiful characters". Characteristic patterns of functional quantities F1, F2 and F3 of the lower-level functions for physical parameters (for example, the surface potential of a photoreceptor body) are prepared. When a fault repair is implemented by changing a value of a physical parameter, a tradeoff occurs between lower-level functions which are influenced by the physical parameter. That is, taking into account the functional quantities F1, F2 and F3 of the lower-level functions, the value of the physical parameter is set so that the functional quantity of the function of "more beautiful characters" is maximized.
    Type: Grant
    Filed: October 11, 1994
    Date of Patent: March 18, 1997
    Assignee: Mata Industrial, Co., Ltd.
    Inventors: Yoshiki Shimomura, Sadao Tanigawa, Yukihiro Mori, Yasushi Umeda, Tetsuo Tomiyama, Hiroyuki Yoshikawa
  • Patent number: 5610689
    Abstract: A detector for detecting status quantities in processes of an image forming apparatus and a correction mechanism for changing parameters are connected to a controller. By virtue of this arrangement, the amount of current associated with a primary charging device in a latent-image process, the surface potential of a photoreceptor drum and a voltage correction coefficient are fed into the controller as status quantities. By using the entered status quantities as well as membership functions and fuzzy rules that have been stored in an internal memory of the controller, the controller executes fuzzy reasoning and outputs a signal indicating the failure rate or rate of erroneous setting of each processing element.
    Type: Grant
    Filed: January 25, 1996
    Date of Patent: March 11, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yuji Kamiya, Atsushi Takeda, Toru Katsumi
  • Patent number: 5234257
    Abstract: A mobile mining machine for cutting a tunnel in rock has a wheel-like cutterhead assembly supported by a pitch boom assembly that causes movement of the cutterhead assembly in the vertical plane. A swing boom assembly supports the pitch boom assembly and is supported by the main frame of the mobile mining machine. In one embodiment the swing boom assembly has a pivot axis that is tilted from vertical and swings the cutterhead and the pitch boom during mining to cut a tunnel having a wide, flat floor. During mining, a gripper assembly having a floor gripper shoe and a roof gripper shoe brace the mobile mining machine in the tunnel. Thrust is provided by thrust cylinders located between the gripper shoes and the main beam. Extension of the thrust cylinders moves the cutterhead assembly, main beam, and rear portion of the mobile mining machine forward relative to the gripper assembly due to slidable engagement of the main beam and gripper assembly.
    Type: Grant
    Filed: October 11, 1991
    Date of Patent: August 10, 1993
    Assignee: The Robbins Company
    Inventors: David B. Sugden, John Turner, Robert J. Boyd