AU2008286694A1 - Pedal assemblies and apparatus used therewith - Google Patents

Description

WO 2009/021283 PCT/AU2008/001170 1 PEDAL ASSEMBLIES AND APPARATUS USED THEREWITH FIELD OF THE INVENTION This invention relates to pedal assemblies used in draglines to actuate 5 various movements of a dragline bucket, and particularly to provide slewing control. This invention is not limited to such applications, but for illustrative purposes reference will be generally made to such an application. It is to be understood that this invention could be used in other equipment, such as in stripping shovels, road and port construction machinery, military tanks, gun turrets 10 and the like. In addition this invention relates to control gear assemblies, brackets, fixtures or other apparatus that may be utilised with pedal assemblies. BACKGROUND OF INVENTION Unless explicitly indicated to the contrary, none of the following prior art 15 constitutes common general knowledge in the art. Draglines are generally used in strip-mining operations to move the overburden from above the material to be mined, such as coal. A dragline bucket is suspended from a boom or a truss supported by a hoist rope which enables the lowering and lifting of the bucket. The bucket is also coupled to a drag rope. 20 In a typical cycle of excavation, the bucket is positioned above the material to be excavated and the bucket is lowered and then dragged along the surface of the material. The bucket is then lifted by the hoist rope and a swing operation rotates the dragline machine maneuvering the bucket to a place where the excavated material is to be dumped by releasing the dragrope causing the bucket 25 to tilt and empty. An operator in the cabin of the dragline generally uses hand controls to operate the hoist and drags the bucket and two foot pedals which control lateral or rotational swing movement of the bucket. The swing pedals are pushed down left to swing the boom and bucket left and vice versa. The two pedals are joined with 30 a solid inverted connection meaning that when the left pedal is pushed the right pedal will travel up and vice versa. Known swing pedal systems are made by Bucyrus Erie, Marion and P&H where the gear control assemblies are located below the floor the operator's cabin WO 2009/021283 PCT/AU2008/001170 2 in a dragline. There are many problems with these known dragline swing pedal controls, especially in relation to servicing. Dust, oil leaks and general mechanical problems over time may interfere with known pedal swing assemblies causing the operation of the dragline to fail. 5 Servicing may be problematic because of confined space and accessibility to the gear controls due to positioning of the gear control system. In many cases, the need to use equipment such as a cherry picker or platform lift from outside the cabin may be needed to fix a problem. Problems may require the removal of the floor of the cabin, total dismantling of the gear controls or repair of parts off site 10 causing downtime and needless hours wasted. One solution to the serviceability issue has the housing mounted within the cabin on a flat lower plate base. The left and right pedals are pivoted at their heel ends essentially at cabin floor level on the lower base plate with the housing located between the pedals. Left and right pedal shafts pass through respective 15 end walls of the house above the base plate and are operated by the pedals via respective roller crank arms, the lost motion rollers operating on the underside of the pedals. The inner ends of the shafts are coupled to each other in opposed rotation by respective bevel gears acting through a reversing idler bevel gear. At least one of the shafts is acted on by a counter spring to bias the coupled shafts 20 and their respective pedals to a neutral position. An operating shaft is mounted parallel to the pedal shafts and is driven by a pedal shaft sector gear acting on an operating shaft pinion gear. The operating shaft may operate rotary devices such as rotary potentiometers and rotary transducers, and/or cam operated devices such as microswitches. 25 The housing intrudes into the cabin space where the pedals of the prior art naturally locate. The location of the pedals at either side of the housing means the operator must adopt an excessively wide stance if the housing is to be of sufficient width to accommodate the reversing gear train assembly, counter spring assembly, and operating shaft and devices assembly. 30 SUMMARY OF INVENTION In the specification the terms "comprising" and "containing" shall be understood to have a broad meaning similar to the term "including" and will be WO 2009/021283 PCT/AU2008/001170 3 understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the terms "comprising" and "containing" such as "comprise", "comprises", "contain" and "contains". 5 This invention in one aspect resides broadly in a pedal assembly comprising a housing having a pair of pedals pivotally mounted on an upper surface thereof at a selected spacing, said pedals being coupled via respective links to an opposing-action mechanism in said housing, an operating shaft mounted in the housing and driven by said opposing-action mechanism, and one 10 or more signal generating devices operated by said operating shaft, the mechanism having a neutral position where said pedals lie in a common plane, said housing being mounted for rotation about an axis which lies substantially in said common plane to adjust the rake of said pedals. It has been surprisingly determined that pedals on the top of a housing that 15 would ordinarily be unusable if mounted to the cabin floor by being relatively too high are rendered useful and ergonomic if adjusted by being raked toward the operator according to the operator's preference. By this means, the pedal assembly can be wholly in the cabin and be serviceable in situ. The pedal spacing is ergonomic. 20 The housing is preferably a low-profile housing. In order that the housing be low profile, the opposed action mechanism may comprise left and right pedal shafts passing through respective end walls of the housing and operated by the pedals via links to respective crank arms mounted on the shaft ends, the shafts being coupled to each other in opposed rotation, the operating shaft being 25 mounted in the housing parallel to and horizontally spaced from the pedal shafts and driven off one of the pedal shafts. By this means the profile of the housing may be reduced to close to the dimension of the signal generating devices operated by the operating shaft. The opposing action may be provided by coupling the pedal shafts though bevel gears and an idler gear journalled to the 30 housing. The mount may be secured to the cabin floor. Alternatively the mount may be associated with an operator console or seat. The mount may be rake adjustable only, or may be provided with one or more of means to adjust reach WO 2009/021283 PCT/AU2008/001170 4 (the distance from the operator console to the pedals) and height. The mount may be adapted to enable the housing to be rotated away from the cabin floor for servicing. Where provision for servicing is provided by the mount rotating away from the cabin floor, the housing is preferably provided with a machine screw-fixed 5 and gasketed service cover on the underside of the housing. When cantilevered from the operators console or seat the mounted pedal assembly is at the end of a significant lever. In order to oppose the lever forces in use the mounting may include a brace which extends from the mounting to the seat or consol along the cabin floor. By this means any tendency for the mount to bend the console or seat 10 frame is countered by the brace bearing on the cabin floor. In another aspect the invention resides in a pedal assembly including a housing having a top wall, left and right pedals pivoted on the top wall, left and right pedal shafts passing through respective end walls of the housing and operated by the pedals via links to the respective crank arms mounted on the shaft 15 ends, the shafts being coupled to each other in opposed rotation, and operating shaft mounted in the housing and driven off one of the pedal shafts, and one or more signal generating devices operated by said operating shaft. One advantage of preferred embodiments is that the top mounting of the pedals enables the pedals to be at least partially over the top of the mechanism in 20 the housing, thus allowing a narrower stance on the pedals. For example, the respective links may be disposed to the region of the outer edge of its pedals and be adapted to operate close to a respective side wall of the housing though a link aperture provided in the top wall. Preferably, one shaft is longer than the other to make for a larger space for 25 devices. This invention in another aspect resides in a pedal assembly that actuates movement of a device via a controller, said pedal assembly including: two inverted connected pedals operatively connected to at least one gear that drives at least one contact assembly, whereby when driven the contact 30 assembly sends a signal to the controller, said controller adapted to translate the received signal into instructions and to transmit the instructions to actuate a desired movement of the device, WO 2009/021283 PCT/AU2008/001170 5 wherein the gear, contact assembly and controller are enclosed within the interior of a housing having a removable cover, said pedals being located external to the housing, and wherein the housing and pedals are connected as a unit whereby upon 5 leverage of the unit from above a base enables the interior of the housing to be accessible when the cover is removed. Preferably, the pedal assembly actuates the swing movement of a dragline or shovel bucket. This invention may also suitably operate the movement of a gun turret, tank or machinery used in road, port construction and other civil engineering 10 operations. The pedal assembly could also operate any directional movement of a device or apparatus depending on the types of selection of gear, contact assembly, controller, type of machinery, etc. It is preferred that seals such as gaskets are placed in areas where dust may be able to enter into the housing. However, leather or synthetic boots, 15 bellows or the like may be used as well. The controller may be an encoder or a resolver. The contact assembly may include at least three contacts, but suitably there are at least six contacts to provide more precise signals. The contact assembly may be separated over different areas in the housing, such as split between four 20 contacts in one area and two in another area or the like. However, it is preferred that the contacts are in single assembly to avoid timing problems and to limit the need to recalibrate two or more separate assemblies. Suitably, the removable cover is located on the opposed side of the housing to the pedals. The pedal assembly may be adjustable mounted to the floor, 25 operator's chair or console/s by suitable mounting frames, support arms, brackets or the like. The base may be the floor where the operator's chair is located. For example, the floor may be the cabin floor of a dragline. In one embodiment, the pedals are pivoted at the heel end of the operator. In a preferred embodiment the pedal may be substantially pivoted centrally so the 30 operator can better utilize their toes and heel for moving the pedal. This may provide more control and flexibility being more ergonomic for the operator. Advantageously, servicing or repair of the pedal assembly can be conducted onsite by leverage of the peddle assembly of the invention as a single WO 2009/021283 PCT/AU2008/001170 6 unit, removing the cover of the housing to assess the equipment in the interior of the housing. BRIEF DESCRIPTION OF DRAWINGS 5 In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate one or more preferred embodiments of the invention and wherein: FIG. 1 is a perspective view of a pedal assembly suitable for use in the present invention; 10 FIG. 2 is an operating system of the pedal assembly of FIG. 1; FIG. 3 is an exploded view of the apparatus of FIG. 1; FIG. 4 is a side view of the apparatus of FIG. 1, mounted on a bracket; FIG. 5 is a front end view of the arrangement of FIG. 4; FIG. 6 is a front perspective view of a detail of the arrangement of FIG. 4; 15 FIG. 7 is a rear perspective view of a detail of the arrangement of FIG. 4; and FIG. 8 is an alternative a bracket for use in an assembly in accordance with the present invention 20 DESCRIPTION OF THE PREFERRED EMBODIMENTS In addition, terms such as "front", "back", "base", "top", "side", "bottom", "left", right", "end", etc refer to the orientation or configuration of a swing pedal or other related apparatus when used according to the illustrations and to assist in indicating points of reference when viewing the accompanying figures. It is to be 25 understood that these terms do not limit the present invention to any specific orientation or configuration of the invention. Example I Figs. I to 7 illustrates a pedal assembly 10 in accordance with the invention 30 and including a cast aluminium alloy housing 11 having an upper footplate 12 to which are pivoted a pair of pedals 13. End walls 14 of the housing are overhung by the foot plate 12 and have the ends of respective shafts 15 passing there through. The shafts 15 each mount a crank 16 connected to the centre of a WO 2009/021283 PCT/AU2008/001170 7 respective pedal 13 by links 17 passing through apertures 20 in the foot plate 12. The foot plate 12 has integrally cast pedal pivot lugs 21 as well as internally threaded pedal limit stop turrets 22. A cover 23 is machine screwed and gasketed to the housing 11. 5 The shafts 15 form part of a control mechanism 24 which is built on a plate chassis 28. The shafts 15 each mount a bevel gear 25 on the inner end, the respective bevel gears being coupled by an idler gear 26. One of the shafts mounts a rack sector 27 that engages a pinion 30 on an operating shaft 31 which mounts cam set operating a pack 32 of rotary signal switches and a rotary resolver 10 or encoder 33. The signal is output to a data connector 34 to which a multiconductor signal cable connecting the assembly to the controlled slewing motors such as electro-hydraulic slewing motors. As illustrated in Figs. 4 to 7, the housing 11 is mounted on a bracket assembly 35 comprising a pair of spaced primary brackets 36 bolted to the 15 operator console lower cross member 37 and extending forward of the console. A floor brace 40 is co-secured by the bolts 38 to resist deformation of the cross member under usage loads, and is required because the cross member is not of sufficient section to resit bending. A track arm 41 is pivoted at 42 to each primary bracket and the end is 20 adjusted for height by the engagement of a pin 43 with any one of three apertures 44. The removal of the pin 43 also enables the track arm to be raised to vertical or beyond for servicing as will become apparent hereinafter. A carriage plate 45 is formed with a roller assembly 46 adapted to travel along a track 47 on the track arm 41 to provide for reach adjustment. Locating pins 48 secure the carriage plate 25 in a selected reach position by engagement with notches 49 in the track arm 41. The respective carriage plates 45 each have a pivot bush or bearing 50 mounting a housing support bracket 51 adapted to be machine screwed to the underside of the foot plate 12 to support the housing without restricting access to the cover 23. The housing support bracket 51 is configured whereby the axis of 30 the pivot 50 passes substantially through the centre of the pedal 13 at its neutral position. The pivot 50 enables the rake of the pedal assembly 10 to be adjusted by rotation about the pivot 50 to optimize ergonomic position of the pedals 13.

WO 2009/021283 PCT/AU2008/001170 8 The rake position is maintained by engagement of captive pins 52 with a selected aperture 53. Example 2 5 In Fig. 8 there is illustrated an alternative bracket 54, the pedal assembly 10 being omitted for clarity. In this case the bracket 54 is adapted to be bolted down to the floor of the cabin and is thus not adjustable in height or reach. However, the bracket 54 is adjustable for rake and includes a floor plate 55 having a pair of spaced pedestals 56 welded thereto. Housing support brackets 57 are pivoted to 10 the pedestals 56. The forward end of the housing support brackets 57 mount links 60 having an inward-directed pin 61 adapted to engage a respective one of a series of notches in notch bars 62 welded near the forward edge of the floor plate 55. By this means, the rake of the housing support brackets 57 may be adjusted. The respective links 60 are interconnected by a handle 63. An aperture 64 15 through the floor plate 55 corresponds to the cabin floor aperture when retrofitting to a cabin which has had its BE brand pedal removed and allows the control cable to pass through. It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and 20 variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein set forth.

Claims (13)

1. A pedal assembly comprising a housing having a pair of pedals pivotally mounted on an upper surface thereof at a selected spacing, said pedals being coupled via respective links to an opposing-action mechanism in said housing, an operating shaft mounted in the housing and driven by said opposing-action mechanism, and one or more signal generating devices operated by said operating shaft, the mechanism having a neutral position where said pedals lie in a common plane, said housing being mounted for rotation about an axis which lies substantially in said common plane to adjust the rake of said pedals.

2. A pedal assembly according to claim 1, wherein the opposing-action mechanism comprises left and right pedal shafts passing through respective end walls of the housing and operated by the pedals via links to respective crank arms mounted on the shaft ends, the shafts being coupled to each other in opposed rotation, the operating shaft being mounted in the housing parallel to and horizontally spaced from the pedal shafts and driven off one of the pedal shafts.

3. A pedal assembly according to claim 2, wherein the opposing action is provided by coupling the pedal shafts though bevel gears and an idler gear journalled to the housing.

4. A pedal assembly according to claim 1, wherein the mount is secured to an operator console or seat within a cabin.

5. A pedal assembly according to claim 1, wherein the mount is associated with a cabin floor.

6. A pedal assembly according to claim 1, wherein the mount is provided with one or more of means to adjust reach and height of the pedals.

7. A pedal assembly according to claim 1, wherein the mount is adapted to enable the housing to be rotated away from a cabin floor for servicing. WO 2009/021283 PCT/AU2008/001170 10

8. A pedal assembly according to claim 7, wherein the housing is provided with a service cover on the underside of the housing.

9. A pedal assembly according to claim 4, wherein the mount includes a brace which extends from the mounting to the seat or console along the cabin floor.

10. A pedal assembly including a housing having a top wall, left and right pedals pivoted on the top wall, left and right pedal shafts passing through respective end walls of the housing and operated by the pedals via links to the respective crank arms mounted on the shaft ends, the shafts being coupled to each other in opposed rotation, and operating shaft mounted in the housing and driven off one of the pedal shafts, and one or more signal generating devices operated by said operating shaft.

11. A pedal assembly according to claim 10 wherein the respective links may be disposed to the region of the outer edge of its pedals and be adapted to operate close to a respective side wall of the housing though a link aperture provided in the top wall.

12. A pedal assembly according to claim 10 wherein one shaft is longer than the other to make for a larger space for devices.

13. A pedal assembly that actuates movement of a device via a controller, said pedal assembly including: two inverted connected pedals operatively connected to at least one gear that drives at least one contact assembly, whereby when driven the contact assembly sends a signal to the controller, said controller adapted to translate the received signal into instructions and to transmit the instructions to actuate a desired movement of the device, wherein the gear, contact assembly and controller are enclosed within the interior of a housing having a removable cover, said pedals being located external to the housing, and WO 2009/021283 PCT/AU2008/001170 11 wherein the housing and pedals are connected as a unit whereby upon leverage of the unit from above a base enables the interior of the housing to be assessable when the cover is removed.