Classifications

• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02F—DREDGING; SOIL-SHIFTING
  • E02F3/00—Dredgers; Soil-shifting machines
  • E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
  • E02F3/28—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets
  • E02F3/34—Dredgers; Soil-shifting machines mechanically-driven with digging tools mounted on a dipper- or bucket-arm, i.e. there is either one arm or a pair of arms, e.g. dippers, buckets with bucket-arms, i.e. a pair of arms, e.g. manufacturing processes, form, geometry, material of bucket-arms directly pivoted on the frames of tractors or self-propelled machines
  • E02F3/345—Buckets emptying side-ways

Definitions

• the present invention relates to an arrangement of the kind set forth in the preamble of Claim 1.
• the bucket of such an assembly shall be locked to the holder in the central position in some reliable manner, and to this end is provided with locking devices which co-act with the journal devices used.
• the journal devices may, alternatively, be releasable, such as to permit selective dumping on either side.
• Malfunctioning of the bucket locking devices may also be due to other causes. For instance, subsequent to activating the operating valve for side-dumping in one direction, e.g. on the left, the operator may activate the controls for side-dumping in the other direction, on the right, before the first dumping operation has been completed.
• SE-B-355 848 (Leijon) describes a hydraulic drive arrangement for two mutually independent functions, sometimes referred to as "all-in-one-cylinder", which includes two double-acting hydraulic rams, the pistons of which each have a specific starting position and with which each of the pistons can be opera ed, through a locking device, in a direction from its starting position solely when the other piston is located in its starting position, said locking device comprising at least one hydraulic valve arrangement which is controlled mechanically by movable elements of the hydraulic.
• Such a drive arrangement may find advantageous use in an assembly which comprises a side-dumping bucket of the kind meant here, by virtue of the fact that it can be given a more compact and robust construction than other known hydraulic drive arrangements, thereby reducing the requirement of construction space to a corresponding extent, an advantage of the highest significance in connection with excavating and loading buckets.
• the known drive arrangement is characterized by the fact that none of the two hydraulic pistons is able to leave its starting posi ⁇ tion once one of the other pistons has left its starting position.
• the other hydraulic ram remains inoperative, with its piston locked in its starting position.
• Various different types of tractor implement holders for side-dumping buckets of the kind meant here are also known to the art from S ⁇ -B-308 487, S ⁇ -3-317 030 and S ⁇ -3-322 166 (all to Leijon).
• These known arrange- ents include different mechanical locking and latch ⁇ ing arrangements for locking or latching the tipping bearings of the bucket, and are based on the principle that the bucket side-dumping movements are affected through a mechanical coupling located between the hydraulic ram or rams and the devices which lock the bearing shaft about which side-dumping is effected and release the opposing bearing shaft.
• an object of the present invention is to provide an improved arrange ⁇ ment in an assenbly of the kind concerned which exhibits improved operational reliability, which will simplify the work of the tractor driver in connection with maneu- vering the bucket, and which will ensure accurate lock ⁇ ing locking of the bucket to the holder in the central position.
• a further object is to provide an arrangement of the aforesaid kind which will eliminate the risk of a side- dumping operation being executed when the components of corresponding locking devices do not co-act correctly with one another.
• the locking devices have the stated fora and are noveable to the locking position concentrically with the geonetric axis of the jouraaling arrangenent, it is possible with compact and reliable configuration of the devices required to effect side dumping of the bucket to provide the separate arrangements necessary in accor ⁇ dance with the invention to achieve the desired reli- ability of the assembly as a whole.
• the devices associa ⁇ ted with the separate hydraulic circuits and required in accordance with the invention may namely be arranged in the close proximity of each journal arrangenent and more specifically adjacent the valve blocks of said arrange- ents.
• valve blocks are connected by hoses to a main block mounted centrally on the holder in connection with the centre part of the tipping ram and accommoda ⁇ ting valve functions operative in effecting positive and safe selective side-dumping.
• the hydraulic circuit includes a valve means, suitably a so-called kick-down- val e.
• valve of this kind Because the function of a valve of this kind is depen ⁇ dent on a pre-determined pressure in a separate control circuit, which in turn presumes that a corresponding locking device has moved to its locking position, it is ensured that bucket dumping movement will not take place unless the locking device in question is outside its locking position.
• each of the hydrau- lie locking devices for effecting locking of the bearing arrangement is arranged to co-act with a valve arranged in connection with an opposing journaling device, suit ⁇ ably a so-called sequence valve of the kind described in Claim 2.
• valve which is preferably activated at a pressure of, for instance, 120 bars, which pressure is lower than the pressure at which the kick-down-valve is activated, e.g. a pressure of 140 bars, will ensure that the bucket will take a correct position, locked to both journaling devices, under all circumstances, before it is possible to side-tip the bucket.
• the hydraulic circuit will preferably include a valve mounted in connection with each journaling arrangement, for instance a so-called button valve of the kind set forth in Claim 4.
• This valve is constructed for mechanical activation of the bucket when said bucket is located in its rest position on the holder, and is operative to prevent the flow of pressure fluid to either of the hydraulic lock- ing devices - and therewith also indirectly to the tipping or dumping ram - unless the bucket is in its correct position on the holder at both ends.
• the hydraulic locking devices of the journaling arrangements co-act with separate sensors effective in detecting electro-induc- tively whether or not the locking devices have taken their correct locking positions, and if such is not the case in activating a latching valve which interrupts the supply of pressure fluid.
• the assembly may also be provided with appropriate optical and/or acoustic and/or like devices which will make the tractor driver aware of any malfunctions or faults with regard to intended functions of the assem ⁇ bly.
• the inventive arrangement will circumvent or usual causes of malfunctioning encountered with earlier known assemblies of this kind, and also faults which are related to wrong handling of the assembly operating valve. For instance, if the driver activates the operat ⁇ ing valve for side-dumping to the left and then changes his mind and immediately activates the valve for side- dumping to the right, the bucket of the inventive arrangement will automatically return to its starting position. It is necessary to produce new, positive operating pulses which initiate the aforedescribed control functions before the desired, alternative dump- ing movement can be effected. Further characteristic features of the invention will be apparent from the following description of a preferred embodiment thereof. The description is made with refer- ence to the accompanying schematic drawings.
• FIG. 1 is a perspective view of a tractor implement holder intended for an assembly which includes a side- dumping excavating and loading bucket in accordance with the invention.
• Figure 2 is a perspective view of the assembly holder including bucket dumping hydraulic systems and joumal- ing arrangements for bucket dunping movements.
• Figure 3 illustrates a hydraulic circuit and shows the valve functions included in the hydraulic circuit of the assenbly.
• Figure 4 is a cross-sectional view of an assembly or journaling arrangenent provided with . hydraulic locking systems and locking devices.
• FIG. 1 and 2 Shown in Figures 1 and 2 is an excavating assembly comprising a holder 2 and an excavating and loading bucket 3.
• the holder is carried by tractor arms which can be swung in the vertical plane such as to pivot the holder for front dumping of the bucket about a horizon- tal axis.
• the bucket 3 can also be swung for side-dumping relative to the holder 2, with the aid of a hydraulic dumping ram arrangement which is pivotally journaled to the holder and generally referenced by the numeral 4.
• the bucket can be tipped sideways about either one of two journal arrangements 11 and 12, each of which co-acts with a respective locking device 33, 34 so as to permit side- dumping about one of the journals, depending en the position of respective locking devices.
• the locking devices 33 and 34 are each activated by locking, hyd ⁇ raulic piston-cylinder devices, the general configura ⁇ tion of which is illustrated in Figure 4.
• the dumping ram 4 is a so-called all-in-one-ran having a central part 13 which is journaled on a shaft 14 for pivotal movement relative to the holder 2.
• the dumping ram includes two double acting piston-cylinder devices 15, 16, the pistons of which have a stirrup-like head 19, 20 mounted on the ends thereof and including a transverse pin or roller 21, 22 for engagement with a respective catch plate 23, 24 on the bucket.
• Each of the pistons of the dunping ran is able to move from its starting position only when the other of said pistons is located in its starting position, as a result of the provision of a locking arrangenent (not shown) provided in the central part 13.
• This locking arrange- ment comprises a hydraulic valve arrangenent vhich is ⁇ echanically controlled by noveable elements of respec ⁇ tive hydraulic rams.
• Each of the stirrup-shaped heads 19, 20 is arranged to engage respective catch plates with some centimetres of free play.
• the reference 6 identifies conduits forming part of a hydraulic circuit intended for action of the dumping ram 4 and the respective locking piston-cylinder devices of the journals 11, 12. This hydraulic circuit together with associated valve functions will be described in more detail hereinafter with reference to Figure 3.
• brackets 43, 44 mounted on the bottom of the bucket 3 are two brackets 43, 44, each of which carries a journal element in the form of a part 46, 47 having the shape of an inverse H or a horseshoe and intended for coaction with the bear ⁇ ing shafts of respective journals 11, 12.
• the tractor operating valve is referenced 50 in Figure 3 and will have the state A when placing the pip-e 70 under pressure for initiating side-dumping around the left journal 11.
• the pipe 71 is the return pipe- When side-dumping around the right journal 12, pressure is applied through the pipe 71 with the valve in the state B.
• the pressure prevailing in the pipe 70 is applied to the central, nain block 55 which, inter alia, includes the three valves 52, 53 and 54 with their respective valve images or states shown in Figure 3. Khen the bucket is tipped sideways around the left journal, these valves are switched to their illustrated positions by means of illustrated pilot circuits.
• the valve block 48 connected with the left journal 11 has three valves, namely a button valve 61 operable by the bucket 3, a sequence valve 63 actuable at a pre ⁇ determined pressure, e.g. 120 bars, and a kick-down- valve 65 operable at a higher pressure, e.g. 140 bars.
• the button valve 61 is activated mechanically by the bucket 3, when the bucket is located in its rest posi ⁇ tion, wherewith the valve image for fluid passage is activated.
• the sequence valve 63 activates its valve image for fluid passage when the aforesaid pre-determined pres ⁇ sure, e.g. 120 bars, is reached.
• the kick-dovn-valve 65 activates its valve image for fluid passage when the aforesaid higher pressure, e.g. 140 bars, is reached.
• valve block 49 connected with the right journal 12 incorporates corresponding valve functions, namely a button valve 62, a sequence valve 64 and a kick-down valve 66.
• Each dumping ram 15 and 16 respectively co-acts with a latching valve 56 and 57, each having an associated pilot circuit which is activated by a kick-down-valve 65 and 66 respectively.
• valve image A of the operating valve 50 is established by the the tractor driver, wherewith the pipe 70 is placed under pressure and the three valves 52, 53 and 54 in the main block 55 take the states illustrated in Figure 3.
• the pressure is propagated through the pipes 72, 74 and 75b to the button valve 61, the fluid-passage valve image of which is established solely when the bucket is correctly positioned on the holder. Presuming that the tucket is correctly position, propa ⁇ gation of pressure continues to the central part of the hydraulic piston-cylinder device 11, the pistons 35 and piston reds 37 of which move the locking devices 33 into their respective locking positions.
• Figure 4 illustrates an embodiment in which separate inductive sensors 80 are arranged in respective locking piston-cylinder devices, such as to detect whether or not the pistons of the locking devices have actually moved to their outer terminal positions. If this is not the case, an electrical latching valve, referenced 51 in Figure 3, is activated, said valve then interrupting the supply of pressure fluid from the operating valve.
• the pressure prevailing in the pipe 76 has ensured that the locking pistons 33 have reached their terminal positions and that a higher pressure has been generated in the pipe 76 and 75b, this higher pressure propagating through the pipe 75b to the sequence valve 64 connected to the locking hydraulic piston-cylinder device 12 on the opposing side.
• the sequence valve is activated so as to permit fluid to flow, this fluid being supplied to the locking hydraulic piston- cylinder device of the right journal arrangement 12, such as to move the locking devices 34 to their release positions.
• the pressure in the pipe system 75b, 75a, 76 will increase until a pre-deternined pressure of 140 bars has been reached, whereupon the kick-dovn-valve 65 is activated, in the nanner described above with reference to Figure 4.
• the latching valve 36 is then activated through the associated pilot circuit 90, this valve thus ensuring that hydraulic pressure is applied to the hydraulic dumping ran 15 such as to side-tip the bucket about the left journal arrangement.
• valves 61, 64 and 65 have been activated prior hereto.
• the sequence valve 64 is con- nected to the opposing, right journal arrangement 12, whereas the other two valves, i.e. the button valve 61 and the kick-down-valve 65 are located in the region of the left journal arrangement.
• the sequence valve 65 will not be activated and the buckets will not be tipped.
• the two button valves 61, 62 will check whether or not the bucket is in its correct position before pressure fluid is delivered for movement of either of the locking devices of said locking arrange- ment to its release position.
• the inductive sensors 80 shown in larger scale in Figure 4 and operative to determine whether or not the piston reds 37 - and therewith the locking devices 33 - have been moved to their outer locking positions, are also indicated in Figure 3.
• the active working parts of the piston reds 37 are preferably treated in a suitable nanner, e.g. coated with a hardnetal layer.
• the sensors 30 work in cooperation with electrical conductors 81 which supply current to the electrical latching valve 51, provided that the piston rods are not in their outer terninal positions.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Mining & Mineral Resources (AREA)
• Civil Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Structural Engineering (AREA)
• Operation Control Of Excavators (AREA)
• Fluid-Pressure Circuits (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=20372875

Family Applications (1)

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Cited By (1)

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Citations (6)

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• 1988
  • 1988-07-08 SE SE8802582A patent/SE466506B/sv not_active IP Right Cessation
• 1989
  • 1989-06-30 EP EP89907867A patent/EP0425534A1/en not_active Withdrawn
  • 1989-06-30 US US07/634,888 patent/US5141288A/en not_active Expired - Fee Related
  • 1989-06-30 JP JP1507289A patent/JPH03505763A/ja active Pending
  • 1989-06-30 WO PCT/SE1989/000376 patent/WO1990000650A1/en not_active Application Discontinuation

Patent Citations (6)

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