Patents Assigned to Komatsu Limited
  • Patent number: 6392205
    Abstract: A disc heater is applied to a temperature control apparatus which controls a temperature of an object to be processed on at least one surface thereof. In the disc heater, wire-like heating elements are laid on a plate surface in a predetermined pattern and power feeding portions are disposed at ends of the wire-like heating elements. The pattern formed by the wire-like heating elements comprise a large number of arc portions disposed on a large number of concentric circles, and a surface area of the arc portions is 70% or greater, more preferably, 85 to 95% of a surface area of the entire pattern. With this feature, it is possible to effectively reduce the local excessively heated portion to the utmost, and to uniformly heat the entire heating surface, thus realizing an ideal topology pattern of the disc heater.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: May 21, 2002
    Assignee: Komatsu Limited
    Inventor: Mikio Minonishi
  • Patent number: 6357820
    Abstract: A work vehicle is provided that permits easy routine daily inspection services of a rear mounted engine in the vehicle. The vehicle has a cab covering a rear engine compartment. The cab is pivotally mounted on the frame of the vehicle. An engine hood is in turn pivotally mounted on the cab and covers the engine in the engine compartment. Accordingly, the hood can be pivoted or rotated to expose the engine for routine daily maintenance while the cab and the engine hood can be pivoted or rotated to expose the entire engine compartment for periodic heavy duty maintenance.
    Type: Grant
    Filed: August 23, 2000
    Date of Patent: March 19, 2002
    Assignee: Komatsu Limited
    Inventors: Isao Nagatsuka, Takeshi Endou, Junji Mimuro, Hirofumi Tanaka
  • Patent number: 6325104
    Abstract: A hydraulic circuit of the present invention comprises a single pump, a precedence valve connected to a discharge pipe of the pump and having a high-pressure side output port and a low-pressure side output port for respectively distributing pressure oil to a high-pressure side circuit and a low-pressure side circuit, a high-pressure specified operation valve connected to one of the output port of the precedence valve, an actuator connected to the high-pressure specified operation valve, a pressure reducing valve connected to the other output port of the precedence valve, low-pressure specified operation valves connected to an output port of the pressure reducing valve, and another actuator connected to the low-pressure specified operation valves. When a load is applied to the actuator connected to the high-pressure specified operation valve, the pressure oil from the pump is supplied to the high-pressure specified operation valve with higher priority.
    Type: Grant
    Filed: February 2, 2000
    Date of Patent: December 4, 2001
    Assignee: Komatsu Limited
    Inventor: Kouji Yamashita
  • Patent number: 6270173
    Abstract: In a travelling crawler belt in which a pair of left and right links are connected by pins respectively press-fitted into the corresponding links, a fixing end surface of the pin or the links is continuously and locally pressed and deformed in an axial direction of the pin from the fixing end surface, along an inner or outer peripheral portion of an opening of a pin-press-fit hole. Then, a part of the opening peripheral portion of the end of the pin or the link is enlarged or reduced in diameter, so that the diametrically increased or reduced portion is retained and fixed to a mating retaining space. With this fixing method, it is possible to easily and strongly couple the links and the pin, and to obtain a fixing structure of the links and the pin for a crawler belt capable of sufficiently securing a holding force of the pin in the axial direction.
    Type: Grant
    Filed: September 15, 1999
    Date of Patent: August 7, 2001
    Assignee: Komatsu Limited
    Inventors: Akira Hashimoto, Teiji Yamamoto, Hiroyuki Nakaishi, Kenichi Hisamatsu, Seiji Miyaura
  • Patent number: 6248973
    Abstract: In a laser marking method for making a dot mark on a semiconductor wafer by using laser beam, molten splashes which arise at the laser marking are prevented from adhering to a surface of the wafer and a shape of the dot mark is kept in a stable posture with its visibility being ensured even after the marking made throughout various and multistage steps in a manufacturing process by the semiconductor apparatus. The method comprises forming a transparent thin film on at least a dot mark-formation area of a semiconductor wafer body of the wafer; irradiating the dot mark-formation area with laser beam having a wavelength selected in advance, on the transparent thin film; melting and deforming the wafer body by the laser beam transmitting the transparent thin film to form a dot mark; and by utilizing the heat generated when the wafer body is melted, deforming the transparent thin film, along with the deformation of the dot mark, into the same shape as the dot mark without a breakdown of the transparent thin films.
    Type: Grant
    Filed: March 11, 1999
    Date of Patent: June 19, 2001
    Assignee: Komatsu Limited
    Inventors: Yukinori Matsumura, Yukihiko Sugimoto, Kotaro Hori
  • Patent number: 6144397
    Abstract: A laser marking method and an apparatus thereof which realize stamp processing with a beautiful appearance and a high precision, without reducing the manufacturing efficiency. The laser marking method comprises a step of sequentially displaying divisional patterns each corresponding to one scanning line of a first deflector, a step of sequentially scanning the divisional patterns with a laser beam from a laser oscillator by the first deflector, and a step of moving a stamp position on a work surface for every one of scanning transmission beams respectively transmitted through the divisional patterns, in a direction perpendicular to a scanning direction, by a second deflector, thereby to synthesize and stamp the divisional patterns.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: November 7, 2000
    Assignee: Komatsu Limited
    Inventors: Teiichirou Chiba, Masato Moriya, Akihiko Souda
  • Patent number: 6065799
    Abstract: A cabin is movable along the outer side surfaces of an operator cab floor by a vertical drive means. Specifically, pinions fixed to left and right end portions of a shaft are driven and rotated by motors installed on the operator cab floor. Rack gears engaged with the pinions are fixed to the cabin. Even when the cabin is moved and situated at its lowermost position, where the lower edges of the cabin project downwards below the operator cab floor, by the rack gears by rotations of the pinions, a single door which is continuous in the vertical direction can be installed on a side plate. Therefore, even when the whole height of the cabin is lowered to its limit, the door can be opened and closed without troubles. The shaft also functions to synchronize the rotations of the left and right pinions mechanically, thereby preventing torsion of the cabin.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: May 23, 2000
    Assignees: Komatsu EST Corporation, Komatsu Limited
    Inventors: Tohru Suwabe, Shinji Iguchi
  • Patent number: 5966472
    Abstract: An automatic recognition method capable of accurately determining edges of a concavity or convexity in order to achieve an improved measuring accuracy in recognition of a concavity or convexity. This method comprises the steps of: converting a photographic image of an object having a concavity or convexity defined therein into data in a specified feature space; obtaining a plurality of points that exist outside a virtual circle determined by a virtual center of the concavity or convexity, the virtual center being established for each elementary area of the image converted into the feature space data; obtaining the equation of a plane that passes through the plurality of points; detecting symmetric pairs of pixels in each elementary area of the feature space data with respect to the corresponding virtual concavity or convexity center; and recognizing the position of the concavity or convexity of the object when the symmetric pixels satisfy the equation of the plane.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: October 12, 1999
    Assignee: Komatsu Limited
    Inventors: Takayuki Kataoka, Ken'ichiro Matsumoto