Spaced Pivots Patents (Class 37/187)
-
Patent number: 9650118Abstract: This invention relates to deep-water underwater transportation in mining operations, and can be used for the placement of geological survey and mining equipment. The present underwater transport module comprises a body (1), ballast tanks (2) with adjustable buoyancy, and a system (3) for pumping a working medium in and out, said working medium being water from outside the transport module.Type: GrantFiled: April 30, 2014Date of Patent: May 16, 2017Inventor: Vladyslav Stanislavovych Kvyatkovskyy
-
Patent number: 9388023Abstract: The present invention relates to a particulate-handling bucket assembly that provides a sound seal between an extended lip section and an extended cavity section located on opposing scoops of the bucket assembly. The seal is formed by abutting elastomeric material located within a cavity of the extended cavity section against an abutting end of the extended lip section. The elastomeric material has an exposed edge which butts against the abutting end of the extended lip section, with the exposed edge having an exposed height that is greater than or equal to an abutting height of the abutting end of the extended lip section.Type: GrantFiled: March 14, 2014Date of Patent: July 12, 2016Assignee: Anvil AttachmentsInventors: John H. Gauthier, Laura G. Martin, Jon A. Craft
-
Patent number: 9303384Abstract: The present invention provides a system and method to efficiently and effectively dredge in the presence of hard rock. An additional aspect of the present invention is to provide a system that induces cavitation bubbles and/or a vortex flow within a dredging cutter head by use of water jets mounted within a cavity of the cutter head. The cavitation bubbles and/or vortex flow produced by the water jets urge comminution of hard rock encountered during dredging operations, providing a more effective and efficient dredging of waterways than conventional approaches.Type: GrantFiled: April 17, 2014Date of Patent: April 5, 2016Assignee: Colorado School of MinesInventors: Christopher J. Wyatt, Hugh Bennett Miller
-
Patent number: 9284715Abstract: Disclosed a device for digging diaphragms, including a framework and a half-shell support body, fixed in the lower part of the framework, which supports a first pair of half-shells moved to open and close by a first actuation system. The device also has a reservoir operatively connected to the first pair of half-shells to contain the soil dug by half-shells. The reservoir is normally positioned between the framework and the half-shells and has a volume configured to contain an amount of soil corresponding to the amount of soil dug by such half-shells during a single operating cycle of the device. The device can also include separation means actuated for isolating the soil contained in the reservoir.Type: GrantFiled: September 15, 2014Date of Patent: March 15, 2016Assignee: SOILMEC S.P.A.Inventors: Stefano Trevisani, Ezio Biserna, Jasmin Curic, Marco Pedrelli
-
Patent number: 9200425Abstract: A grasping apparatus that can be miniaturized and compacted to be mountable in small-size equipment or the like and reduced in weight, and a construction machine in which the grasping apparatus is mounted. The grasping apparatus has a gear mechanism 30 in which an annular inner gear 71 is disposed concentrically with a sun gear 73, plural intermediate gears 68 are interposed in an annular space between the inner gear 71 and the sun gear 73, the plural intermediate gears 68 are freely rotatably supported by a bracket secured to a construction machine or the like, a grasping apparatus swing cylinder 23 rotated by the sun gear 73 or the inner gear 71 is equipped to the construction machine or the like as equipment, an upper fork 36 is secured to the inner gear 71, a lower fork 32 that grasps a conveyance target object 90 or the like in cooperation with the upper fork 36 is secured to the sun gear 73 to which rotating force is transmitted from the inner gear 71 through the intermediate gears 68.Type: GrantFiled: May 22, 2013Date of Patent: December 1, 2015Assignee: JHL CO., LTD.Inventor: Kiichi Takehana
-
Patent number: 8756837Abstract: Fastening device designed to fasten a collecting container including: at least one pivot-member assembled so as to swivel around an axis on a mobile arm and including at least one first transverse arm provided with a first fixing structure and at least one second transverse arm provided with axial bores, at least two fasteners fixed onto the collecting container, the first fastener being provided with a second fixing structure working in conjunction with the first fixing structure, the second fastener, provided with axial bores, and a pin, designed to be inserted and to slide inside the axial bores when they are aligned. There exists at least one bore of a group, called the “central bore”, which is conical and which is surrounded by two bores of the other group, called “peripheral bores” which are cylindrical. The pin has a conical shoulder complementary to the central bore.Type: GrantFiled: December 8, 2009Date of Patent: June 24, 2014Assignee: E.C.L.Inventors: Arnaud Wattel, Stéphane David
-
Patent number: 8607480Abstract: The two jaws of the bucket each consist of two rigid portions, the receptacle and the shovel, which are hinged onto on another around the pivoting axis. They are connected to the chassis and to the control cylinder by the suspension arm and the moving arm. The hinges of each jaw between the receptacle, the shovel, the suspension arms, the moving arms, the cylinder, and the chassis imply four hinged systems, each having four push rods. During a closing movement of the bucket from the position of maximum separation of the jaws, a relative pivoting of limited amplitude occurs in alternating directions between the receptacle and the shovel of each jaw.Type: GrantFiled: November 30, 2009Date of Patent: December 17, 2013Inventor: Serge Vuistiner
-
Patent number: 7207127Abstract: A grab bucket, in particular motor-driven underwater grab bucket, has first and second half-scoops. The scoops can be moved relative to on another from an open position into a closed position by a hydraulic cylinder. The opening angle of the half-scoops is monitored by a sensor which is connected to a control and monitoring device. The sensor is integrated in the hydraulic cylinder and generates an actuating-travel signal which corresponds to the actuating travel of the hydraulic cylinder.Type: GrantFiled: July 6, 2004Date of Patent: April 24, 2007Assignee: Wolfgang Rohr GmbH & Co. KGInventor: Wolfgang Rohr
-
Unit for the collection, cleaning and calibration of electrolysis pots used for aluminium production
Patent number: 6643957Abstract: A unit for the collection, cleaning and calibration of electrolysis pots and, in particular, of anodic orifices thereof, as the anodes of an installation for the production of aluminum by igneous electrolysis are replaced, includes two buckets hinge-mounted at the level of a lower end of a shovel-bearing chassis which is vertically movable. The lower edge of each of the buckets is movable in a circular direction by a connecting rod assembly. Also the shovel-bearing chassis is joined to a vertical guide mast and is mechanically linked to the buckets-supporting chassis. The buckets-supporting chassis is moveable relative to the shovel-bearing chassis and integrates the connecting rod assembly for closing and opening the buckets with the buckets being hinge-mounted at the lower end of the buckets-supporting chassis.Type: GrantFiled: October 23, 2001Date of Patent: November 11, 2003Assignees: Reel SA, ASMIInventors: Gérard Piron, Serge Huon -
Patent number: 6557277Abstract: A hydraulic circuit for a working machine is provided which prevents a decrease in the working speed of a clamshell bucket upon expansion of an expansion arm, so that improvement of the operability can be achieved. A hydraulic circuit for a working machine is configured such that a clamshell bucket is attached to a tip end of an expansion arm and the expansion arm and the clamshell bucket are operated by pressure oil supplied from a common pressure source. The operating pressure is reduced for driving the expansion arm to the expansion side based on the operating pressure for opening the clamshell bucket. By the configuration, the clamshell bucket can be opened rapidly, and improvement of the operability is achieved.Type: GrantFiled: August 7, 2001Date of Patent: May 6, 2003Assignee: Shin Caterpillar Mitsubishi Ltd.Inventors: Yoshiyuki Hibi, Yorimichi Kubota, Nobuaki Matoba, Shinya Nozaki
-
Patent number: 6446364Abstract: A grab having at least one shoe for support against the walls of the hole that the grab is digging, and elements for moving the shoes between a folded-in position in which they remain alongside the frame and an unfolded position in which they press against the walls of the hole. Preferably, unfolding of the shoes is performed automatically when the grab reaches the bottom of the hole. The excavator of the invention is provided with such a grab. A very high digging force is achieved without an increase in the volume or in the weight of the grab.Type: GrantFiled: September 8, 2000Date of Patent: September 10, 2002Inventor: Juan Vicente Herrero Codina
-
Publication number: 20020104236Abstract: A bucket of a type designed to attach to the stick of an excavator, using pre-existing pins. The bucket is powered by a hydraulic cylinder, the lines of which attach to excavator controls. Striker forks are mounted onto the stick of the excavator at a predetermined position. The clean-out system is a wiper plate incorporated into the bucket as the “roof”, which is designed to follow the inner contour of the sides of the bucket. As the bucket is filled, the wiper plate moves to the top of the bucket; when the bucket is emptied, the wiper plate contacts the striker forks, which force the material out of the bucket, preventing build-up of material on the inside of the bucket.Type: ApplicationFiled: November 7, 2001Publication date: August 8, 2002Inventor: Gene Klager
-
Patent number: 6347464Abstract: A clam bucket of a type designed to attach by way of a pin (20) through vertical lugs (92) to the stick of an excavator making the attachment process fairly simple. These vertical lugs (92) are part of the rotational housing (32) assembly which, in conjunction with a rotational mounting plate (22) at the top of a square tubing extension (48) enable the bucket (70) to make a full 360° turn. The bucket (70) halves are each powered by a hydraulic cylinder (56), the lines of which attach to excavator controls. The clean-out system is a pair of wiper plates (86) incorporated into the bucket (70) halves. These wiper plates (86) sweep the bucket (70) halves each time the bucket opens and closes preventing buildup of material. This self-cleaning hydraulic clam bucket can be manufactured in size to suit the consumer.Type: GrantFiled: December 29, 1999Date of Patent: February 19, 2002Inventor: Gene Klager
-
Patent number: 6134815Abstract: A monitoring device for motor-driven underwater grab bucket dredges contains a bucket gear suspended on a cable. The device ensures reliable monitoring and controlling of the operating condition of the bucket gear 4. There is at least one sensor connected to the grab bucket gear for sensing a measured value. There is a computer connected to the sensor for representing the measured value detected by the sensor.Type: GrantFiled: February 11, 1999Date of Patent: October 24, 2000Assignee: Rohr GmbHInventor: Wolfgang Rohr
-
Patent number: 6023862Abstract: A control system for a rope bucket, the rope bucket being designed for the hoisting and transfer of materials and adapted to be suspended from a hoist trolley transferable along an essentially horizontal travel path. The control system includes a hoist mechanism for hoisting the rope bucket, and a close mechanism for closing and opening the scoops of the rope bucket, and also for hoisting and lowering the rope bucket. The hoist mechanism includes two separate mechanisms, and similarly the close mechanism includes two separate mechanisms which also form the transfer mechanism of the hoist trolley.Type: GrantFiled: September 23, 1998Date of Patent: February 15, 2000Assignee: KCI Konecranes International PLCInventor: Juhani Sirjola
-
Patent number: 5553405Abstract: A power-assisted shovel truck is provided including a swiveling truck and a rotary bucket attached to the truck by a movable arm. A water feed pump and a water feed tank are provided on the truck for pumping water towards the rotary bucket. A conduit communicates with the water feed pump and runs along the arm to the bucket to feed a stream of water to the rotary bucket.Type: GrantFiled: July 21, 1994Date of Patent: September 10, 1996Assignees: Toshihiro Industry Co., Ltd., Miyoshi Co., Ltd.Inventors: Hiroshi Hayashi, Tadashi Miyoshi
-
Patent number: 5540005Abstract: A marine dredging device comprised of scoop buckets hinge-connected to a soil receiver chamber with deployable silt curtains. The silt curtains are deployed to close off the aperture between the scoop buckets and prevent the extrusion of soil. Introduction of pressurized air lowers the water level in the soil receiver chamber to provide a void for dredged soil.Type: GrantFiled: July 21, 1995Date of Patent: July 30, 1996Inventor: Robert P. Lynch
-
Patent number: 5473828Abstract: To excavate sticky soil such as clayey soil, left and right buckets of a clamshell bucket are slightly inclined, thereby reducing the force to pull the buckets from a hole. The clamshell bucket includes left and right buckets which are closable, thereby holding soil, and a hydraulic cylinder having a stroke reserve so as to be further extendible after the buckets are closed, whereby the closed buckets can be displaced sidewardly relative to the vertical.Type: GrantFiled: November 28, 1994Date of Patent: December 12, 1995Assignee: Japanic CorporationInventor: Mitsuhiro Kishi
-
Patent number: 5330242Abstract: A rotatable hydraulic grapple apparatus comprises a yoke assembly having attached to it a hydraulic motor and having within it a channel. A housing is rotatably connected to the yoke assembly and is capable of being rotated by movement of the hydraulic motor. The housing is centered along the longitudinal axis of the yoke assembly such that the longitudinal axes of both the yoke assembly and the housing are collinear. The channel in the yoke assembly communicates with a manifold in the housing. The housing has rigidly attached to it a plurality of chambers, each chamber containing an hydraulic actuator rigidly attached within the chamber. Attached to each hydraulic actuator is a grapple tine. A pressurized fluid supply provides fluid to the yoke assembly channel which communicates the fluid to the housing manifold. The fluid is then communicated from the manifold to each actuator for movement of the actuator which in turn moves the grapple tines.Type: GrantFiled: December 23, 1992Date of Patent: July 19, 1994Inventor: Bobby D. Lucky, Sr.
-
Patent number: 5271170Abstract: A scoop for a mobile implement such as an excavator or an excavator-like device is made in two parts in the form of scoop sections able to be pivoted about parallel pivot axes by a piston and cylinder unit. The scoop includes an attachment head so that the scoop may be pivotally connected with a boom of the mobile implement. In order to pivot the entire scoop laterally, a further piston and cylinder unit is integrally provided for lateral pivoting of the entire scoop about a central pivot axis in the attachment head, the further piston and cylinder unit is connected at one end with a pivot point, preferably one of the pivot axes of one of the scoop sections, and at the other end with a lever. The lever is connected at one end with a pivot point, preferably the other respective one of the pivot axes on the other respective scoop section and the other end of the lever is connected via a link with a projection on the attachment head.Type: GrantFiled: February 9, 1993Date of Patent: December 21, 1993Inventor: Rolf Mieger
-
Patent number: 5199194Abstract: The invention relates to an apparatus, suitable for deployment from small vessels, for obtaining samples of materials from the sea bottom and, more specifically, to a multi-bucket sampler particularly suited for, but not restricted to, gathering samples from bottoms comprising hard or compacted materials and/or having coarse matter, such as gravel, distributed therein. In one embodiment the sampler comprises, in general, a dual bucket assembly pivotally attached to a frame, cover means for the buckets, and an actuator for pivoting the buckets from an open position wherein the buckets can penetrate the bottom to a closed position wherein the buckets are urged against the cover. The apparatus is designed to achieve maximum penetration of the seabed and to prevent washout of the materials collected upon recovery. The dual buckets provide sample duplication which may be used to assess local variability of bottom conditions.Type: GrantFiled: September 30, 1991Date of Patent: April 6, 1993Assignee: C-CORE-Centre for Cold Ocean Resources Eng.Inventor: William J. Scott
-
Patent number: 4882859Abstract: The invention relates to an excavating bucket including two scoops (13) mounted movably, with respect to a frame (1), from an open terrain-engaging position to a closed position in which they enclose a certain quantity of cuttings. It comprises a central bucket body (5), integral with said frame and including at least two lateral walls (6), the scoops being arranged so that, in closed position, they come toward the central body from both directions with their lateral walls extending from the lateral walls of the central body.Type: GrantFiled: October 25, 1988Date of Patent: November 28, 1989Assignee: SoletancheInventor: Karl Bollinger
-
Patent number: 4602444Abstract: An apparatus for transplanting trees comprising an elevating mechanism attached to an automatic travelling driving device and a digging-up device attached to said elevating device, wherein: said digging-up device includes a frame from which a pair of left and right supporting rods extend forwardly, said rods being pivotally provided with inwardly bent scooping plates, and a hydraulic cylinder is interposed between said scooping plates and said frame or said supporting rods, said hydraulic cylinder being actuated to open and close said scooping plates.Type: GrantFiled: April 15, 1985Date of Patent: July 29, 1986Assignee: Futaba Kogyo Yugen KaishaInventor: Yoshimasa Endo
-
Patent number: 4405167Abstract: A clamshell comprises a U-shaped halfscoop carrier, two halfscoops pivoted to the legs of the half-scoop carrier on axes which are parallel to each other and to the central crosspiece connecting the legs, and actuating levers, which are secured to the half-scoops and to which the piston rod and the cylinder, respectively, of a transversely extending hydraulic actuator are pivoted at the free ends of the levers. The tubes connecting the top edges of the side walls of the half scoops are formed adjacent to their ends with radial slots extending over part of their periphery. The end portions of the T-shaped legs are provided with the bearing bores and extend through the radial slots. The side walls are formed with bores, which are aligned with the bores of the tubes and with the bearing bores and receive the pivot pins for the halfscoops.Type: GrantFiled: March 2, 1981Date of Patent: September 20, 1983Inventor: Alfred Kinshofer
-
Patent number: 4328987Abstract: A rope-actuated load lifting and carrying assembly is characterized by the provision of at least one first rope guide disposed so that its axis of rotation is disposed at all times below a reference plane defined perpendicularly to the joinder plane between the gripping elements and containing the axis of rotation of the center pin. The assembly is also characterized by a head arrangement wherein at least three first rope guides are disposed in a semicircular arrangement below the reference plane, the guides being angularly separated by a predetermined amount. A head assembly includes at least three second rope guides disposed in a semicircle at or above the plane containing the connection of the head with the corner arms, the second rope guides being angularly separated by a predetermined amount.Type: GrantFiled: September 11, 1979Date of Patent: May 11, 1982Inventor: Adolph F. Zoudlik
-
Patent number: 4178030Abstract: The invention contemplates an improved grapple or grab-bucket construction of the double-acting hydraulically activated variety, wherein the normal bucket-open position is determined by a stiffly yieldable abutment which yields to permit a short further energy-absorbing bucket-opening displacement in the presence of the mechanical shock encountered upon dropping the open grab bucket onto a relatively hard base to be excavated. The short further shock-induced displacement elevates hydraulic pressure in the actuation system, which elevated pressure is vented by a relief valve in common with the hydraulic actuators of all buckets in the grapple.Type: GrantFiled: April 20, 1978Date of Patent: December 11, 1979Assignee: Firma Johannes FuchsInventor: Hans Dolinsek
-
Patent number: 4176872Abstract: A grab or the like substantially comprising a frame or upper structure having for each grab bucket pivoting levers, at the end of which there is positioned the pivot point of a grab bucket, while each grab bucket can furthermore be pulled by means of a rope to the opened position and via a lever system connected to a pulley block movable in the frame, into the closing position, whereby each grab bucket is connected through a pair of levers to a pulley block such that, in the opened position of the grab buckets, this can form an angle of 180.degree., while the grab buckets, in an intermediate position of the movable pulley block, sealingly abut against the lower and side boundary edges.Type: GrantFiled: January 23, 1978Date of Patent: December 4, 1979Assignee: Nemag, B.V.Inventor: Leendert van Huuksloot
-
Patent number: 4143901Abstract: A mechanical grab consisting essentially of a frame within which round-bottomed scoops with straight-walled sides can be rotated about an axis in such a manner that, when the grab shuts, the mutually facing walls of the scoops are upwardly movable in overlapping relationship while the relative speed with which each of the scoops rotates about its axis is different.Type: GrantFiled: November 9, 1976Date of Patent: March 13, 1979Assignee: Nemag, B.V.Inventor: Leendert van Huuksloot
-
Patent number: 4143900Abstract: A pair of bucket bowls are pivotally suspended from a power head frame on the exterior of which is mounted a pair of hydraulic rams. Each of the hydraulic rams has one end pivotally connected to the power head frame and another end pivotally connected to a respective bucket bowl. The power head frame houses power components for actuating the rams and is formed of a horizontal deck, and vertical side and end bulkheads integrally formed to provide a watertight enclosure.Type: GrantFiled: March 7, 1977Date of Patent: March 13, 1979Assignee: Condor International CorporationInventor: Joseph F. Longo
-
Patent number: 4129329Abstract: A pair of bucket bowls are pivotally suspended from a power head frame in which is mounted two pairs of hydraulic rams. Each of the hydraulic rams has one end pivotally connected to the power head frame and another end pivotally connected to a bucket bowl. The power head frame houses power components in specially designed compartments so as to achieve a symmetrical configuration to balance the forces acting on the bucket bowls.Type: GrantFiled: March 7, 1977Date of Patent: December 12, 1978Assignee: International Dynetics CorporationInventor: Joseph F. Longo
-
Patent number: 4124243Abstract: This multi-purpose grab bucket of the type comprising a pair of hydraulically actuated symmetrical pivoting shells or scoops has a main central vertical hydraulic cylinder and piston actuator and lateral oblique hydraulic cylinder and piston actuators, and valves for selectively supplying hydraulic fluid under pressure to the central actuator or the lateral actuators for operating the assembly as a "digging" bucket or as a "rehandling" bucket, or in a third mode intermediate the "digging" and "rehandling" modes.Type: GrantFiled: August 1, 1977Date of Patent: November 7, 1978Assignee: International Harvester CompanyInventor: Lucien A. Raffin
-
Patent number: 4071155Abstract: Two pincer bucket halves, each including a horizontal blade, are mounted on a frame for opposed pivotal movement in a normally horizontal plane about respective parallel normally vertical axes. An upstanding back spans the axes and upstanding sides extend perpendicularly from the outer edges of the pincer blades. To pick up material, such as a pile of leaves or branches, from a ground surface, the pincer bucket halves are opened and advanced toward the pile with the opposed blades in contact with the ground surface. After the bucket halves are located on opposite sides of the pile, the bucket halves are brought together so that the blades are closed, thereby undercutting and supporting the material, with the vertical sides of the buckets confining the material in combination with the vertical back. The embraced material may then be elevated and transported within the bucket. The material is discharged by tilting the bucket forwardly and opening the bucket halves.Type: GrantFiled: May 17, 1976Date of Patent: January 31, 1978Inventors: Samuel A. Hart, William E. Hart
-
Patent number: 4047626Abstract: A loader vehicle includes a forwardly disposed bucket made up of a pair of jaws, with linkage means associated therewith so that, with the jaws in their open state such jaws are initially moved forwardly of the vehicle, and then subsequently the jaws are guided by such linkage means into a closing action.Type: GrantFiled: March 24, 1975Date of Patent: September 13, 1977Assignee: Caterpillar Tractor Co.Inventor: Thomas C. Meisel, Jr.
-
Patent number: 4047313Abstract: This grab bucket comprises a pair of shells or scoops pivoted to the lower portion of a frame structure and operatively connected to a vertical hydraulic cylinder and piston actuator of which the piston rod is held against translation in relation to the frame structure, the upper end of the cylinder of said actuator carrying the pivot pins of links connected to the pair of shells or scoops. The frame structure comprises on the one hand an upper member rigid with the piston rod of said hydraulic actuator and on the other hand a frame structure body detachable from the upper member. The shells themselves are detachable from the base of the hydraulic cylinder to permit the operation of the grab bucket not only as a digging bucket but also as a rehandling bucket after disassembling the frame structure body and connecting the links to the upper member.Type: GrantFiled: February 9, 1976Date of Patent: September 13, 1977Assignee: International Harvester CompanyInventor: Jean-Pierre Luc Bricon
-
Patent number: 4024655Abstract: A suction pipe device for suction dredgers having at least two functionally opposed combined cutter and crusher tools mounted near the bottom opening of the suction pipe, to cut and crush and feed material to be dredged.Type: GrantFiled: July 7, 1975Date of Patent: May 24, 1977Inventor: Karl Friedrich Schweitzer
-
Patent number: 4012856Abstract: A grab bucket for pourable material and a method of operating the same, according to which during the closing of the grab bucket, at least one of the two grab bucket sections is at its closing edge subjected to oscillations with amplitudes in the direction toward the closing movement. The grab bucket has at least one of the two grab bucket sections provided with an oscillation starter.Type: GrantFiled: March 26, 1975Date of Patent: March 22, 1977Assignee: Fried. Krupp Gesellschaft mit beschrankter HaftungInventor: Wilhelm Schwarz
-
Patent number: 3965999Abstract: A drilling grab for pile foundations and well boreholes wherein the drilling grab comprises a grab body supporting circular grab spades which tilt from an open position to a closed position about pivot pins carried by the grab body. A radially projecting abutment interchangeably connected to the outer periphery of the grab body is engageable with the back of the grab spades when the same are in an open position. The abutment overlaps the periphery of the grab body and is characterized in that they consist of extension members adapted to grab spades of different sizes. The members are supported on radially projecting ribs located on the grab body.Type: GrantFiled: January 29, 1975Date of Patent: June 29, 1976Assignees: Elisabeth Hochstrasser nee Wack, Jurgen HochstrasserInventors: Hans Mathieu, Jurgen Hochstrasser
-
Patent number: 3949498Abstract: A grab bucket particularly suitable for dredging the bottom of the sea, rivers, lakes, etc. is provided with bottom plates at the lower portion of a framework from the bottom of which pivotally hang a pair of bucket shells, whereby the bottom plates cooperate with the bucket shells to shield their upper openings when they are swung upwards about their pivotal portions to put their respective confronting edges tightly together in a conventional manner.Type: GrantFiled: October 30, 1974Date of Patent: April 13, 1976Assignee: Mitsubishi Seiko Kabushiki KaishaInventors: Hisao Iwata, Gentaro Hasewaga, Kameichi Shimizu