Heavy equipment pedal assembly

Abstract

The pedal assembly has a housing with a pair of pedals pivotally mounted at a selected spacing to an upper surface of the housing. An operating shaft with first and second ends is mounted for rotation within opposing side walls of the housing with a crank connected to each end of the operating shaft. Each crank is connected to a respective pedal through a linkage under tension when a pedal is depressed. A gear assembly drives a signal generating device and is adapted to translate a generated signal into instructions to actuate desired movement of the heavy equipment. A calibration stop adjacent to the crank limits a range of movement of the crank and rotation of the operating shaft. Depression of respective pedals results in rotation of the operating shaft in opposing directions, the position of each pedal is calibrated to meet pre-determined parameters.

Description

[0001] HEAVY EQUIPMENT PEDAL ASSEMBLY

[0002] FIELD OF THE INVENTION

[0003] This invention relates to controls for heavy equipment and to pedal assemblies for steering such equipment. In particular, the invention is adapted for steering or controlling an elongate boom for virtually any purpose.

[0004] BACKGROUND OF THE INVENTION

[0005] It should be noted that reference to the prior art herein is not to be taken as an acknowledgement that such prior art constitutes common general knowledge in the art.

[0006] The control of heavy equipment such as the boom of an open cut mining excavator presents a problem since movement of the boom is achieved by powerful swing motors which are sensitive to control by the human operator. This control is usually provided by the operation of two foot pedals, depressing the left pedal results in the boom moving to the left and the right pedal results in movement to the right. Various mechanical linkages typically cause the pedal not being depressed to move upward while the other pedal is depressed. Any operator failure or any flexing or failure in the pedal assembly can result in the boom swinging out of control and causing massive damage.

[0007] Draglines, power rope shovels and excavators are extremely expensive to purchase and maintain. Due to their size and the fact that most operate around the clock, they are expensive to repair, run and require regular maintenance. Therefore any improvements in their operation, any reduction of downtime or any reduction in operator fatigue can represent large savings for the mining industry. It is therefore essential to minimise the amount of downtime and improve operator comfort for these machines.

[0008] One known pedal assembly consists of at least one rod attached to an arm, at least one sector gear attached to the arm and a translation gear interconnected with the sector gear. Movement of the rod causes movement of the arm and sector gear, resulting in movement of the translation gear which is translated into an electrical signal to move the boom of the dragline excavator. However the rod or rods in this assembly are thrown into compression by operation of the control pedals. By operating the control pedals in compression there is the possibility that the rods can bend, or the linkages fail under compression. Further there is no mechanism to return the pedals to a neutral control position if the operators feet leave the pedals during movement of the boom.

[0009] Another known pedal assembly consists of a housing having a pair of pedals pivotally mounted on an upper foot plate which are coupled via links to shafts interconnected in reversing relation. One shaft drives an operating shaft activating one or more signal generating devices, the mechanism having a neutral position where the pedals lie in a common plane. The housing is mounted on a bracket assembly for rotation about an axis which lies substantially in the common plane of the pedals to adjust the rake of the pedals. Although the opposing action mechanism driven by the pedals of this assembly provides for more stable control, the driving shafts are still in compression with the attendant instability and there is no fail safe neutralizing mechanism.

[0010] Another improved pedal assembly which is designed to improve operational safety is described in related WO 2011 / 011812, entitled A Pedal Assembly for Steering Systems, filed on July 23, 2010. A pedal assembly consists of a pair of pedals connected to a shaft which is rotated by links connected to the pedals such that the links operate in tension when the pedals are depressed. The pedals have spring loaded plungers which return them to a neutral position when there is no pressure on the pedals. Although this assembly improves the control precision of the operator a number of problems still exist which make this pedal system difficult to install and problematic due to component failures.

[0011] One component which has failed is the contactor assembly which provides precise signals to the signal generating device when operated by the operating shaft. Currently, the contactor assembly has at least three contacts which provide outputs via either an encoder or resolver to control the swing motor speeds when the foot pedals which control lateral or rotational swing movement are depressed. The at least three contacts may include a direction left selected, a neutral selected and a direction right selected contacts. The length of the current contactor assemblies restrict the size of the signal generating device in particular, the encoder which can be utilised within the pedal assembly. The known contactor assemblies also tend to over travel when the pedals are depressed. The over travelling causes the contactor assembly to become jammed stuck in one direction which destroys the selected swing direction contact which leads to uncontrolled swing movement. This uncontrolled movement can lead to damage to any equipment in the path of the swing rotation of the machine and may also cause injury or the death of personnel.

[0012] Another component which limits the operation of the known pedal assemblies is the fixed stops which are associated with each pedal which limit the range of movement of the link and corresponding rotation of the shaft. The fixed stops effectively limit the travel of the respective cranks and pedals. These fixed stops are problematic in that they do not provide for any travel adjustment of the pedal. There is no way of calibrating the pedal assembly so that each pedal produces an identical control reference signal for both left and right swing motion. It is important that the travel distance is the same distance left or right.

[0013] The known swing pedal systems are complex and with relatively large numbers of interconnecting moving parts there is a greater chance that at least one component will break down and thereby require the power rope shovel, excavator or dragline to be stopped. The constant push for improved safety and efficiency to maximise profits means that any downtime can create a serious financial concern.

[0014] Clearly it would be advantageous if a heavy equipment pedal assembly for a steering system could be devised that helped to at least ameliorate some of the shortcomings described above. In particular, it would be beneficial to provide a heavy equipment pedal assembly to improve operational safety with improved efficiency or at least provide the public with a useful choice.

[0015] SUMMARY OF THE INVENTION

[0016] According to a first aspect, the present invention provides a heavy equipment pedal assembly comprising: a housing with a pair of pedals pivotally mounted at a selected spacing to an upper surface of the housing; an operating shaft mounted for rotation within the housing, the operating shaft having a first end spaced apart from a second end; a crank connected to each end of the operating shaft through openings in a respective opposing side walls of the housing, each crank connected to a respective one of the pair of pedals through an adjustable linkage, each adjustable linkage being operable in tension when the respective pedal is depressed; a gear assembly mounted within the housing, the gear assembly is driven by the rotation of the operating shaft; a signal generating device driven by the gear assembly and adapted to translate a generated signal into instructions and to transmit the instructions to actuate a desired movement of the heavy equipment; a calibration stop is located adjacent to each crank, each calibration stop has an adjustable means to set a range of movement of the link and corresponding rotation of the operating shaft; a spring operated plunger is positioned on an underside of each pedal, the spring operated plunger biasing the associated pedal toward a neutral position; and wherein depression of each respective pedal results in rotation of the operating shaft in opposite directions and the desired movement of the heavy equipment.

[0017] Preferably, the signal generating device may further comprise a contactor assembly and a motion controller. The contactor assembly may be a rotary contactor with two or more contact rows. Preferably, the contactor assembly may further comprise a physical rotation stop tab, the physical rotation stop tab is adapted to prevent over travel of the contact rows. The motion controller may be a resolver or an encoder. Preferably, the encoder maybe an absolute encoder or an absolute encoder with a process field bus interface.

[0018] Preferably, each calibration stop may comprise: a base mounted on the opposing side walls of the housing; and a slide adjustably mounted to the base, the slide having a crank engaging arm which is adapted to contact the crank to set the movement of the crank and corresponding rotation of the operating shaft.

[0019] Preferably, each crank may have a mounting arm extending perpendicular from a cylindrical body, the mounting arm connecting the crank to each pedal through the linkage and the cylindrical body is mounted on each end of the operating shaft. When mounted on the operating shaft the mounting arm of each respective crank may be positioned diametrically opposite on opposing ends of the operating shaft, when each respective pedal is depressed, one of the pair of pedals will rotate the operating shaft clockwise and the other one of the pair of pedals will rotate the operating shaft anti-clockwise.

[0020] Preferably, when one of the pair of pedals is depressed, the operating shaft may rotate clockwise and generate the signal from the signal generating device to actuate the desired movement and an amount of travel in a first direction, when the other one of the pair of pedals is depressed, the operating shaft may rotate anti-clockwise and generate the signal from the signal generating device to actuate the desired movement and an amount of travel in a second direction. Preferably, when each pedal is depressed the position of the crank engaging arm of each calibration stop with respect to the mounting arm of each crank may be calibrated to set the amount of travel in the first and second directions and prevent the engagement of the physical rotation stop tab of the contactor assembly.

[0021] Preferably, each pedal may be calibrated to ensure that the amount of travel in the first and second directions produces an identical signal output from the signal generating device.

[0022] Preferably, a rotation of each pedal may be set to not exceed a predetermined angular rotation. The pre-determined angular rotation may be approximately 150 degrees.

[0023] Preferably, the adjustable linkage connected to each pedal may be adapted to set a height or rake angle position for each pedal with respect to the upper surface of the housing.

[0024] Preferably, the gear assembly may comprise a sector gear extending perpendicular from an operating shaft mounting plate, when the operating shaft is rotated clockwise or anti-clockwise, the sector gear engages with a contact assembly gear to rotate the contactor assembly.

[0025] Preferably, a central mounting flange may extend from a bottom surface and adjacent to a heel of each pedal, the mounting flange may connect each pedal to the respective adjustable linkage and the upper surface of the housing.

[0026] Preferably, the operating shaft, the gear assembly and the signal generating device may be enclosed within the housing by a removeable cover, the removable cover may be positioned on a bottom surface of the housing. The operating shaft, the gear assembly and the signal generating device may be mounted on a removable base within the housing.

[0027] Preferably, the heavy equipment pedal assembly may be mounted on an adjustable pivot bracket secured to a cabin floor of the heavy equipment. Alternatively, the heavy equipment pedal assembly may be mounted on an adjustable slide rotation bracket on an operator console of the heavy equipment.

[0028] Preferably, the desired movement controlled by the heavy equipment pedal assembly may be a slewing or swing action. Preferably, the generated signal of the signal generating device may control a swing motor control system to achieve the desired movement and a movement speed of a swing motor. Alternatively, the generated signal of the signal generating device may control a pair of proportional valves driving an electro-hydraulic slewing motor to achieve the desired movement and a movement speed of the heavy equipment.

[0029] Preferably, the opposing side walls of the housing may be overhung by a portion of the upper surface of the housing, and the crank, the calibration stop and the adjustable linkage of each pedal may be positioned beneath the overhung portion of the upper surface.

[0030] In accordance with a further aspect, the present invention provides a method for controlling movement of a boom of a heavy equipment comprising: providing the heavy equipment having a machine upper portion with a rigid, cable-supported boom extending therefrom, a first drive system having a first motor which moves the machine upper portion along a path in a swing direction; providing a pedal assembly in accordance with the first aspect to actuate the swing movement of the machine upper portion along the path; calibrating each pedal of the pedal assembly to meet a set of pre-determined operating parameters; depressing a first pedal to rotate an operating shaft in a first direction, the rotation of the operating shaft generating a signal from a signal generating device to translate the generated signal into instructions and to transmit the instructions to swing the machine upper portion in a first swing direction; releasing the first pedal causes a spring operated plunger positioned on an underside of the first pedal to bias the first pedal toward a neutral position; depressing a second pedal to rotate the operating shaft in a second direction opposite to the first direction, the rotation of the operating shaft generating a signal from the signal generating device to translate the generated signal into instructions and to transmit the instructions to swing the machine upper portion in a second swing direction opposite the first swing direction; and releasing the second pedal causes a spring operated plunger positioned on an underside of the second pedal to bias the second pedal toward the neutral position.

[0031] Preferably, the pedal assembly may comprise any of the features of the first aspect.

[0032] In accordance with a still further aspect, the present invention provides a pedal assembly that actuates a swing movement of a boom of a heavy equipment, the pedal assembly comprising: a housing with a removeable cover positioned on a bottom surface of the housing, and a pair of pedals pivotally mounted at a selected spacing to an upper surface of the housing; a removable base plate mounted within the housing and adapted to receive an operating shaft mounted for rotation on the removable base, a gear assembly mounted for rotation on the operating shaft, and a signal generating device driven by the gear assembly and adapted to translate a generated signal into instructions when one of the pair of pedals is depressed and to transmit the instructions to actuate the swing movement of the heavy equipment; a crank connected to opposing ends of the operating shaft through openings in opposing side walls of the housing, each crank is positioned diametrically opposite on the opposing ends of the operating shaft and when each respective pedal is depressed, one of the pair of pedals will rotate the operating shaft clockwise and the other one of the pair of pedals will rotate the operating shaft anti-clockwise; an adjustable linkage connects each crank to a respective one of the pair of pedals, each adjustable linkage being operable in tension when the respective pedal is depressed; a calibration stop is located adjacent to each crank, each calibration stop has an adjustable means mounted to a base, the adjustable means having a crank engaging arm which is adapted to contact the crank to set a range of movement of the crank and corresponding rotation of the operating shaft; a spring operated plunger is positioned on an underside of each pedal, the spring operated plunger biasing the associated pedal toward a neutral position when each pedal is no longer depressed; and wherein each pedal is calibrated to meet a set of predetermined operating parameters.

[0033] Preferably, the pedal assembly may comprise any of the features of the heavy equipment pedal of the first aspect.

[0034] Preferably, the pedal assembly may be calibrated to: set a position of the signal generating device on the gear assembly so that a rotation travel of the gear assembly is identical for travel in both clockwise and anti-clockwise directions; set the height or rake angle of each pedal with respect to the upper surface of the housing to be approximately identical by adjusting the adjustable linkage associated with each pedal; set each spring operated plunger to be in contact with a bottom surface of each respective pedal when each pedal is positioned in the neutral position; set each calibration stop to limit the rotation of the crank and prevent the activation of the physical rotation stop tab of the rotary contactor in both clockwise and anti-clockwise directions; and set the output from the signal generating device to be identical in both the clockwise and anti-clockwise directions.

[0035] Preferably, once the pedal assembly has been calibrated to meet the set of pre-determined operating parameters, respective locking devices on the gear assembly, the adjustable linkages, the spring operated plungers and the calibration stops may be painted with a tamper proof coating to provide an indication to a user of any tampering of components.

[0036] Any one or more of the above embodiments or preferred features can be combined with any one or more of the above aspects.

[0037] BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be understood more fully from the detailed description given hereinafter and from the accompanying drawings of the preferred embodiment of the present invention, which, however, should not be taken to be limitative to the invention, but are for explanation and understanding only.

[0039] Fig. 1 shows a perspective view of a heavy equipment pedal assembly in accordance with an embodiment of the present invention;

[0040] Fig. 2 is an elevation of the heavy equipment pedal assembly of Fig. 1 from the left side;

[0041] Fig. 3 is a plan view of the heavy equipment pedal assembly of Fig. 1 from the bottom side with a first embodiment of the signal generating device;

[0042] Fig. 4 is a plan view of the heavy equipment pedal assembly of Fig. 1 from the bottom side with a second embodiment of the signal generating device;

[0043] Fig. 5 shows an exploded perspective view of the heavy equipment pedal assembly of Fig. 4;

[0044] Fig. 6 shows an exploded perspective view of the heavy equipment pedal assembly of Fig. 3;

[0045] Fig. 7 is an exploded perspective view of the signal generating device of Fig. 6;

[0046] Fig. 8 is an exploded perspective view of the signal generating device of Fig. 5;

[0047] Fig. 9 is an exploded perspective view of the removable base plate of Figs.

[0048] 7 and 8; Figs. 10 and 11 are perspective and exploded views of the gear assembly which is mounted on the operating shaft of Figs. 7 and 8;

[0049] Fig. 12 is an exploded perspective view of an encoder and rotary contactor as illustrated in Fig. 7;

[0050] Fig. 13 is an exploded perspective view of a resolver and rotary contactor as illustrated in Fig. 8;

[0051] Figs. 14 and 15 illustrate perspective and exploded views of an embodiment of the calibration stop in accordance with the present invention;

[0052] Figs. 16 and 17 show perspective and top plan views of the crank which is attached to either end of the operating shaft in accordance with an embodiment of the present invention;

[0053] Fig. 18 is a sectional view taken along line AA of Fig. 17; and

[0054] Fig. 19 is a sectional view taken along line BB of Fig. 17.

[0055] DETAILED DESCRIPTION

[0056] The following description, given by way of example only, is described in order to provide a more precise understanding of the subject matter of a preferred embodiment or embodiments.

[0057] It is also to be understood that the specific devices and processes illustrated in the attached drawings and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. Additionally, unless otherwise specified, it is to be understood that discussion of a particular feature or component extending in or along a given direction or the like does not mean that the feature or component follows a straight line or axis in such a direction or that it only extends in such direction or on such a plane without other directional components or deviations, unless otherwise specified.

[0058] Reference will now be made to the drawings in which the various elements of embodiments will be given numerical designations and in which embodiments will be discussed so as to enable one skilled in the art to make and use the invention. It will be further noted that the figures are schematic and provided for guidance to the skilled reader and are not necessarily drawn to scale. Rather, the various drawing scales, aspect ratios, and numbers of components shown in the figures may be purposely distorted to make certain features or relationships easier to understand. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein.

[0059] It should be noted in the following description that like or the same reference numerals in different embodiments denote the same or similar features.

[0060] In the broadest form the present invention provides a heavy equipment pedal assembly 10. The pedal assembly 10 has a housing 20 with a pair of pedals 40, 41 pivotally mounted at a selected spacing to an upper surface 27 of the housing 20. The housing 20 is substantially rectangular shaped with a pair of major or longer side walls 23, 24 and a pair of minor or shorter side walls 21 , 22. An operating shaft 115 is mounted for rotation within the housing 20, the operating shaft 115 having a first end 116 spaced apart from a second end 117. A crank 60 is connected to each end 116, 117 of the operating shaft 115 through openings 31 in the shorter side walls 21 , 22 of the housing 20. Each crank 60 is connected to a respective one of the pair of pedals 40, 41 through an adjustable linkage 50. Each adjustable linkage 50 being operable in tension when the respective pedal 40, 41 is depressed.

[0061] A gear assembly 150 is mounted within the housing 20, the gear assembly 150 is driven by the rotation of the operating shaft 115. A signal generating device 120, 140 is driven by the gear assembly 150 and is adapted to translate a generated signal into instructions and to transmit the instructions to actuate a desired movement of the heavy equipment.

[0062] A calibration stop 80 is located adjacent to the crank 60 to set a range of movement of the crank 60 and corresponding rotation of the operating shaft 115. A spring operated plunger 100 is positioned on an underside 45 of each pedal 40, 41 to bias the associated pedal 40, 41 toward a neutral position. Depression of each respective pedal 40, 41 results in rotation of the operating shaft 115 in opposite directions and the pedal assembly 10 is calibrated to meet a set of predetermined operating parameters.

[0063] Figs. 1 to 4 illustrate an embodiment of the heavy equipment pedal assembly 10 in accordance with the present invention. The heavy equipment pedal assembly 10 has two pedals 40, 41 pivotally mounted on top of an upper surface 27 of the housing 20. The housing 20 is a cast aluminium alloy housing 20 having an upper surface footplate 27 to which the pair of heat treated cast aluminium alloy pedals 40, 41 are pivotally mounted. The heat treatment of the pedals 40, 41 improves the mechanical properties of the cast aluminium and in particular the mechanical strength. The upper surface 27 also has mounting holes 34 for receiving fasteners to mount the heavy equipment pedal assembly 10 to an adjustable pivot bracket (not shown) secured to the cabin floor of the heavy equipment. Alternatively, the heavy equipment pedal assembly 10 can be mounted on an adjustable slide rotation bracket on an operator console of the heavy equipment. The adjustable pivot bracket and the adjustable slide rotation bracket allow the user to position the pedal assembly 10 to a desired position for the operator.

[0064] A handle 25 extends from the side wall 23 of the housing 20 to allow a user to hold the pedal assembly 10 so it can be easily installed and adjusted to suit the operators comfort during operation of the heavy equipment pedal assembly 10 and also to facilitate the easy transport of the pedal assembly 10. The housing 20 also has an opening 26A in the side wall 24 for receiving therein the removable electrical connection panel 26 which receives the generated signal from the signal generating device 120, 140 and provides power to the contactor 105 for the pedal assembly 10. By way of example only, the signal generated by the signal generating device 120, 140 provides proportional control of the swing or slewing motors or control to electro-hydraulic proportional valves for controlling slewing hydraulic motors to achieve the desired slewing or swing movement of the heavy equipment.

[0065] As shown in Figs 3 and 4, side walls 21 , 22, and 24 of the housing 20 are overhung by the upper surface portions 28. The bottom surface of the housing 20 is open to allow access to mount the signal generating device 120, 140 within the housing 20. A cover (not shown) is machine screwed and gasketed to the housing 20 to cover the opening to eliminate any contamination of the internal components within the housing 20.

[0066] Each pedal 40, 41 is a heat treated cast aluminium alloy pedal with integrally cast aluminium treads located in the top surface of each pedal 40. 41. The heat treatment of the pedals 40, 41 improves the mechanical properties of the cast aluminium and in particular the mechanical strength. By way of example only, the pedals 40, 41 are strengthened to sustain a weight of 150kg applied to the toe of the pedals 40, 41 to avoid any bending in the pedals 40, 41 . The raised heel 44 on each pedal 40, 41 is provided to prevent the operators feet slipping off the pedals 40, 41 . Located on the bottom surface 45 and extending from the heel 44 of each pedal 40, 41 are angular mounting lugs 42, 43. An outer pair of lugs 43 and a single centre lug 42 pivotally mount each pedal to the upper surface 27 of the housing 20. Bearings are located in each of the mounting lugs 43 and between the bearings and passing through the mounting lug 42 is a bearing spacer which pivotally mount each pedal 40, 41 to the upper surface 27 of the housing 20. The pair of outer lugs 43 only extend to mount the pedals 40, 41 to the upper surface 27 of the housing 20. Each central lug 42 extends downward through openings 33 in the upper surface 27 of the housing 20 to mount each pedal to an adjustable linkage 50 and the operating shaft 115.

[0067] A left pedal 40 and a right pedal 41 are pivotally mounted to the upper surface 27 by pairs of angular brackets 29. The angular brackets 29 are integrally cast with the upper surface 27 of the housing 20. The angular brackets 29 have openings for receiving bearings therein to reduce drag and reduce or eliminate wear when the pedals 40, 41 are depressed. Each pair of angular shaped brackets 29 are spaced apart to provide an opening for receiving pedal lugs 42, 43 extending from the bottom surface 45 of each pedal 40, 41 . Both the angular brackets 29 and the pedal lugs 42, 43 have openings with bearings therein which are aligned to receive a mounting pin. Each mounting pin pivotally mounts the pedals 40, 41 to the upper surface 27 of the housing with fasteners securing the mounting pins in place. The mounting pins may be secured with circlips inserted into recesses in the outer side edge of the openings in the brackets 29.

[0068] Adjustable linkages 50 extend between pedal lug 42 of each pedal 40, 41 and cranks 60 attached to operating shaft 115, so that when each pedal 40, 41 is depressed cranks 60 will rotate the operating shaft 115. Each adjustable linkage 50 consists of a centre stud with threaded ends for receiving rod ends, each rod end has a locking nut for securing the rod end to the centre stud. The rod ends are adjustable on the centre stud to allow a user to adjust and set the pitch angles or height above the upper surface 27 of each pedal 40, 41 .

[0069] The cranks 60 are mounted diametrically opposite from the other crank 60 on opposite ends 116, 117 of the operating shaft 115. Fig. 2 illustrates this action in relation to the left hand pedal 40. The crank 60 is shown mounted vertically upright towards the bottom surface 28 of the upper foot plate surface 27 of the housing 20 and above the operating shaft 115. With the upper end of the crank 60 connected to an end 52 of the adjustable linkage 50. When the left hand pedal

[0070] 40 is depressed in the direction of the arrow, both the crank 60 and the operating shaft 115 will rotate in an anti-clockwise direction as illustrated by the arrow shown on the side wall 21 of the housing 20. Likewise, when the right hand pedal

[0071] 41 is depressed both the crank 60 and the operating shaft 115 will rotate in a clockwise direction. Each adjustable linkage 50 is operated in tension when the respective pedal 40, 41 is depressed.

[0072] Also shown in Fig. 2 is the spring operated plungers 100 which are mounted to contact the bottom surface 45 of each pedal 40, 41 . Each spring operated plunger 100 is adjustable to the pedal pitch of each pedal 40, 41 so that in the neutral position the end of each spring operated plunger 100 is touching the bottom surface 45 of each pedal 40, 41 . Each spring operated plunger 100 is adapted to bias the associated pedal 40, 41 toward a neutral position when an operator removes the depression force on that pedal 40, 41. Each spring operated plunger 100 is mounted by a fastener in the upper surface 27 and extend through openings 35 in the upper surface 27 such that a portion of the body of each spring operated plunger 100 sits above and beneath the upper surface foot plate 27 and adjacent to an outer surface of the side walls 21 , 22 of the housing 20. When the spring inside the spring operated plunger 100 is compressed by an operator depressing a pedal 40, 41 , the calibrated spring tension in each spring operated plunger 100 is designed to return the respective pedal 40, 41 to the neutral positioned when the pedal 40, 41 is released by the operator. The spring compression rate can be altered in each spring operated plunger 100 but needs to be identical for each pedal 40, 41 .

[0073] Also shown in Fig. 2 mounted to the side wall 21 is one of the pair of calibration stops 80. Each calibration stop 80 is located adjacent to the crank 60 to set a range of movement of the crank 60 and corresponding rotation of the operating shaft 115.

[0074] Figs. 3 and 4 show bottom views of the heavy equipment pedal assembly 10. Fig. 3 shows the pedal assembly 10 with a first embodiment of the signal generating device 120 and Fig. 4 show the pedal assembly 10 with a second embodiment of the signal generating device 140. The signal generating devices 120, 140 are mounted within the interior of the housing 20, along with the operating shaft 115 and gear assembly 150. Adjacent opposite ends 21 , 22 of the housing 20 are the adjustable linkages 50 which connect each pedal 40, 41 to the operating shaft 115. One end 52 of each adjustable linkage 50 is connected to the crank 60 the other end 51 is connected to the pedal lugs 42 of each pedal 40, 41 . The pedal lugs 42 extend through the openings 33 at the rear edge of the foot plate 27 and connect to the end 51 of the adjustable linkage 50. Each crank 60 has a cylindrical body which is inserted though openings 31 in the walls 21 , 22 and connect to opposite ends 116, 117 of the operating shaft 115.

[0075] In Fig. 3 the signal generating device 120 comprises a rotary contactor 105 and a motion controller in the form of encoder 121. The encoder 121 generates a variable signal from the signal generating device 120 when the operating shaft 115 is rotated. The encoder 121 is an electro-mechanical device that converts the angular position or motion of the operating shaft 115 to a digital output signal which is supplied to actuate a desired direction and speed of movement of the heavy equipment.

[0076] By way of example only, the encoder 121 may be an absolute rotary encoder which is used to maintain the position information once power is detached from the rotary encoder. The output from the absolute rotary encoder 121 is a specific value in a binary format. This provides the advantage that the encoder’s position is instantly available once power is provided. Alternatively, the encoder 121 may be an absolute encoder with a process field bus (Profibus) interface. The absolute encoder with the Profibus interface transmits the process direction and the velocity or speed of rotation of the operating shaft 115 in binary code. The velocity or speed of rotation of the operating shaft 115 is a direct representation of the movement or force applied to each pedal 40, 41 . The absolute encoder with a Profibus interface enables consistent data transfer between the pedal assembly 10 and the swing or slewing control system of the heavy equipment.

[0077] In Fig. 4 the signal generating device 140 comprises a rotary contactor 105 and a motion controller in the form of resolver 141. The resolver 141 generates the signal from the signal generating device 140 when the operating shaft 115 is rotated. The resolver 141 is a rotary position transducer used for measuring degrees of rotation of the operating shaft 115 and produce an analog output signal which is supplied to actuate a desired direction and speed of movement of the heavy equipment.

[0078] By way of example only, the resolver 141 is an absolute rotary resolver which is used to maintain the position information once power is detached from the rotary resolver 141. This provides the advantage that the resolver’s position is instantly available once power is provided. The resolver 141 outputs signal by energizing the input phase of the resolver 141 with an AC voltage to induce voltage into each of the output windings. The resolver amplitude modulates the AC input voltage in proportion to the Sine and Cosine of the angle of mechanical rotation. That is, the resolver 141 provides a unique Sin / Cos voltage at every point in a 360 degree rotation.

[0079] Figs. 5 and 6 show exploded views of the heavy equipment pedal assembly 10. Fig. 5 shows the exploded view of the pedal assembly 10 with the second embodiment of the signal generating device 140 and Fig. 6 show the pedal assembly with the first embodiment of the signal generating device 120. With the exception of the signal generating device 120, 140 the remaining components of the pedal assembly 10 are identical, as such only Fig. 5 will be described in any detail.

[0080] In Fig. 5, each of the components of the pedal assembly 10 are shown exploded from their normal positions on or within the housing 20 or the upper surface 27. The signal generating device 140 and operating shaft 115 are attached to base plate 111 and mounted on the underside 28 of the upper surface or foot plate 27 and within the walls 21 , 22, 23, 24 of the housing 20. When mounted, each end 116, 117 of the operating shaft 115 is aligned with an opening 31 in the walls 21 , 22 of the housing 20. The openings 31 are sized to allow the cylindrical body 62 of the crank 60 to pass and rotate therethrough. The cylindrical bodies 62 are adapted to attach to each end 116, 117 of the operating shaft 115. A mounting fastener 86 of the calibration stop 80 is received in each opening 32 in the walls 21 , 22 of the housing 20. An end of the spring operated plunger 100 is received through opening 35 in the upper surface 27 of the pedal assembly 10. Each spring operated plunger 100 biases the respective pedal 40, 41 toward a neutral position when the pedal 40, 41 is not depressed. Each pedal 40, 41 is selectively spaced and pivotally mounted at one end to the upper surface 27 by angular brackets 42, 43 extending from under the heel 44 of each pedal 40, 41 . The central angular bracket 42 on each pedal 40, 41 extends through an opening 33 in the upper surface 27 and attaches to one end 51 of the adjustable linkage 50. The other end 52 of the adjustable linkage 50 connects each pedal 40, 41 to the crank mounting arm 61 of each crank 60. When each pedal 40, 41 is depressed each adjustable linkage 50 is operable in tension. The combined movement of each pedal 40, 41 and adjustable linkage 50 rotates each crank 60 in a clockwise or anti-clockwise direction which then rotates the operating shaft 115 in the same direction. The length of each adjustable linkage 50 is calibrated prior to installation in the pedal assembly 10. This ensures that the height or rake angle of each pedal 40, 41 with respect to the upper surface 27 of the pedal assembly 10 is identical for each pedal 40, 41 .

[0081] Figs. 7 and 8 show exploded views of the signal generating devices 120, 140. Fig. 7 illustrates the signal generating device 120 with the rotary encoder 121 attached to the rotary contactor 105. A mounting assembly 110 has a base plate 111 to which bearing mounting blocks 112 are mounted at opposite ends of the base plate 111. The mounting assembly 110 is removably mounted within the housing 20. Each bearing mounting block 112 receives an end 116, 117 of the operating shaft 115 which allows for the rotation of the operating shaft 115 within the housing 20. Gear assembly 150 is mounted adjacent one end 116 of the operating shaft 115 and rotates with the operating shaft 115. A sector gear rack 153 is mounted perpendicular to the operating shaft 115 to rotates the gear 116 which is attached to one end of the shaft extending from the rotary contactor 105. Rotation of the operating shaft 115 in a clockwise or anti-clockwise direction by the pedals 40, 41 will generate a corresponding signal from the rotary encoder 121 through the electrical connectors 122. The electrical connectors 122 provide the control signal to the swing or slewing control system to control the direction and speed of the slewing motors or provide the control signal to a pair of electro- hydraulic proportional valves to control the hydraulic slewing motors to achieve the desired swing or slewing movement and speed of the heavy equipment.

[0082] Fig. 8 shows an exploded view of the signal generating device 140 and provides the same operation of the signal generating device 120 as described and illustrated in Fig. 7, with the exception that the signal generating device 140 has a resolver 141 attached to the rotary contactor 105. Rotation of the operating shaft 115 in a clockwise or anti-clockwise direction by the pedals 40, 41 will generate a corresponding signal from the resolver 141 through the electrical connector 142. The electrical connector 142 provides the control signal to the swing or slewing control system to control the direction and speed of the slewing motors or provide the control signal to a pair of electro-hydraulic proportional valves to control the hydraulic slewing motors to achieve the desired swing or slewing movement and speed of the heavy equipment.

[0083] Fig. 9 illustrates an exploded view of the mounting assembly 110. The base plate 111 is a substantially rectangular plate with two longer and two shorter sides. The base plate 111 is removably mounted within the housing 20. At opposite shorter ends of the base plate 111 bearing mounting blocks 112 are mounted perpendicular to the base plate 111. Each bearing mounting block 112 receives a bearing 119 therein to rotatably mount each end 116, 117 of the operating shaft 115. Each end 116, 117 of the operating shaft 115 is tapered to receive a corresponding tapered section 64 of each crank 60. The tapered section of each end 116, 117 has a channel therein for receiving a locking key 63A. Each locking key 63A mates within a corresponding shaped keyway slot 63 within the tapered section 64 of each crank 60 to lock the crank 60 to the corresponding end 116, 117 of the operating shaft 115 and a fastener secures the crank 60 to the operating shaft 115.

[0084] Figs. 10 and 11 show perspective and exploded views of the sector gear assembly 150 which is mounted adjacent end 116 of the operating shaft 115 and rotates with the operating shaft 115. The sector gear assembly 150 has a base 151 with a mounting aperture 152 which slides over the operating shaft 115 and is secured in place on the operating shaft 115 by fasteners. A sector gear rack 153 is mounted on locating pins on the base 151 and secured in place by fasteners. When the sector gear assembly 150 is mounted on the operating shaft 115 the sector gear rack 153 extends perpendicular to the operating shaft 115 to mesh with and rotate the gear 116 which is attached to one end of the shaft extending from the rotary contactor 105.

[0085] Fig. 12 shows an exploded perspective view of the encoder 121 and the rotary contactor 105. The rotary contactor 105 is mounted on plate 107, the plate 107 is mounted by fasteners to the base plate 111 of the mounting assembly 110. The gear 106 is mounted at one end of the rotary contactor 105, the gear meshes with the sector gear rack 153 to rotate the rotary contacts of the rotary contactor 105. The rotary contactor 105 consists of a two row contact assembly with gold plated contact elements. Each contact block row has two normally open direction (left and right) contacts and one normally closed neutral position contact. The rotary contactor 105 has a spring return (not shown) used as a form of fail-safe to return the rotary contactor 105 to the neutral position when the pedals 40, 41 are not depressed. Whenever the pedals 40, 41 are in the neutral position the rotary contactor 105 will also be in the neutral position. It is critical to the operation of the pedal assembly 10 when installed on the heavy equipment such as a dragline or power rope shovel to ensure that the rotary contactor 105 is in the neutral normally closed position to allow the swing breaks to be released.

[0086] The rotary contactor 105 also has a physical rotation stop tab, the physical rotation stop tab is adapted to prevent over travel of the contact rows of the rotary contactor assembly 105. The two row contacts of the rotary contactor are utilised to provide more room within the housing 20 for mounting a larger rotary encoder 121. Also, the design of the two row contacts allows a user to easily access contact termination terminals to enable the user to more easily replace one set of the contacts without removing the pedal assembly 10 from the heavy equipment.

[0087] Located centrally on the opposite end of the rotary contactor 105 is a socket 109 for receiving one end of the drive connector 124, the drive connector 124 connects the rotary contactor 105 to the encoder 121 . As illustrated, the drive connector 124 at the one end has a square shaped pin which is received within the corresponding shaped socket 109 in the rotary contactor 105. While illustrated as a square pin and socket 109, other shaped pins could be substituted without departing from the present invention. The opposite end of the drive connector 124 has a socket for receiving the end shaft 123 of the encoder 121 . The drive connector 124 is secured to the shaft 123 by a fastener. A mounting adaptor 108A connects the rotary contactor 105 to the encoder 121 .

[0088] The absolute rotary encoder 121 is a flange mounted unit with wiring connectors 122 extending from an end of the encoder 121 . As described above, an absolute rotary encoder 121 is used to maintain the position information from each pedal 40, 41 once power is detached from the rotary encoder 121 . As such, the last position of the encoder 121 is instantly available once power is provided. The absolute rotary encoder 121 is an electro-mechanical device that converts the angular position or motion of the operating shaft 115 to a digital output signal. By way of example only, the output signal from the electrical connectors 122 is supplied to the swing or slewing control system to control the direction and speed of the slewing motors of the heavy equipment.

[0089] Fig. 13 shows an exploded perspective view of the resolver 141 and the rotary contactor 105. The rotary contactor 105 is identical to that described with reference to Fig. 12 and will not be repeated. Located centrally on the opposite end of the rotary contactor 105 is a socket 109 for receiving one end of the drive key connector 144, the drive key connector 144 connects the rotary contactor 105 to the resolver 141. As illustrated, the drive key connector 144 is formed as a square shaped pin which is received within the corresponding shaped socket 109 in the rotary contactor 105. While illustrated as a square pin and socket 109, other shaped pins could be substituted without departing from the present invention. The opposite end of the drive key connector 144 has a socket for receiving the end shaft 143 of the resolver 141 . The drive key connector 144 is secured to the shaft 143 by a suitable fastener. An adjustable mounting bracket 108 connects the rotary contactor 105 to the resolver 141 .

[0090] By way of example only, the absolute resolver 141 is body mounted unit with wiring connector 142 extending from an end of the resolver 141. As described above, the absolute resolver 141 is a brushless rotary position transducer used for measuring degrees of rotation of the operating shaft 115 to produce an analog output signal. By way of example only, the output signal from the electrical connectors 142 is supplied to the swing or slewing control system to control the direction and speed of the slewing motors of the heavy equipment.

[0091] The operation of the heavy equipment pedal assembly 10 will now be described in detail in relation to Figs. 2 to 13 for the left pedal 40 only. The operation for the right pedal 41 is identical to the left pedal 40 with the exception that when the right pedal 41 is depressed the crank 60 and operating shaft 115 rotate in a clockwise direction which rotates the rotary contactor 105 to close the normally open right contacts.

[0092] In-situ the left hand pedal 40 is positioned in the neutral position with the spring operated plunger 100 just touching the bottom surface 45 of the pedal 40. As the left hand pedal 40 is depressed, the adjustable linkage 50 is operable in tension which rotates the crank 60 located on the side wall 21 of the housing 20 in an anti-clockwise direction. This also rotates the operating shaft 115 in an anticlockwise direction. As the operating shaft 115 rotates anti-clockwise this then rotates the sector gear assembly 150 extending perpendicular from the operating shaft 110 downward towards the base 111 of the pedal assembly 10.

[0093] This rotation of the sector gear assembly 150 will then rotate the gear 106 mounted at one end of the rotary contactor 105 in a clockwise direction. This rotation moves the contact rows from the normally closed neutral contacts to close the normally open left direction contacts of the rotary contactor 105.

[0094] The pressure applied to the left hand pedal 40 by the operator is indicative of the speed which the operator requires for the swing movement. The speed of rotation of the operating shaft 115 in an anti-clockwise direction generates a corresponding output signal from the signal generating device 120, 140 through the electrical connector 122, 142. The electrical connector 122, 142 provides the control signal to the swing or slewing control system to control the swing in the left direction and the speed of the slewing motors. Alternatively, the control signal is provided to a pair of electro-hydraulic proportional valves to control the hydraulic slewing motors to achieve the desired left swing or slewing movement and speed of the heavy equipment.

[0095] Figs. 14 and 15 illustrate views of an embodiment of the calibration stop 80. A calibration stop 80 is associated is located adjacent to the crank 60 to set a range of movement of the crank 60 and corresponding rotation of the operating shaft 115. Each calibration stop 80 allows the rotation of each pedal 40, 41 to be accurately calibrated to the heavy equipment pedal assembly 10 for the particular heavy equipment. The calibration saves significant time and money during the installation and change of the pedal assembly 10. Each calibration stop 80 is firstly set to prevent the activation of the physical rotation stop within the rotary contactor 105 when a pedal 40, 41 is fully depressed. In use the calibration stop 80 is set to limit rotation of the crank 60 and operating shaft 115 when each pedal 40, 41 is fully depressed. This ensures that the crank 60 will abut against the adjustable slide plate 88 of the calibration stop 80 before the rotary contactor 105 physical rotation stop tab is activated to prevent over travel of the contact rows of the rotary contactor assembly 105, especially when an operator uses considerable force to fully depress a pedal 40, 41 .

[0096] A mounting fastener or bolt 86 mounts each calibration stop 80 through an opening 32 in the walls 21 , 22 of the housing 20. The mounting bolt 86 passes through a tapered opening 85 centrally located in the base 81 of the calibration stop 80. By way of example only, the base 81 is manufactured from a metal material such as stainless steel. The tapered opening 85 allows the head of the bolt 86 to sit just below the top surface of the base 81 to allow the adjustable slide plate 88 to move laterally along the base 81 . The adjustable slide plate 88 is manufactured from a plastics material such as nylon or any other plastics material. The mounting bolt 86 is secured to the inside of the walls 21 , 22 by fastener 87, the fastener being positioned within the housing 20.

[0097] The base 81 has four threaded openings spaced evenly around the tapered opening 85, each opening is adapted to receive a fastener to secure the adjustable slide plate 88 to the base 81 . A spacing washer 92 is positioned under each pair of fasteners to provide further strength when the adjustable slide plate 88 is secured to the base 81 . Located at one end of the base 81 is the mounting block 82 for the adjusting screw 83. An opening extends through the mounting bock 82 to allow an end of the adjusting screw 83 to be aligned with and contact a plug 90 received within an opening 91 of the adjustable slide plate 88. The plug 90 is manufactured from a metal material such as stainless steel. A locking nut 84 is threaded on the adjusting screw 83 to allow the position of the adjusting screw 83 to be locked in position.

[0098] The calibration of the rotation of each pedal 40, 41 and the output signal from the signal generating device 120, 140 is described in more detail below. In order to correctly position each crank 60 the adjustable slide 88 of the calibration stop 80 is moved laterally on the base 81 so that the crank engaging section 89 of the adjustable slide 88 is correctly placed to abut against the mounting arm 61 of each crank 60 to correctly set the movement of each respective crank 60 and the operating shaft 115. The adjusting screw 83 allows accurate movements of the adjustable slide 88 to calibrate the pedal assembly 10. Each pedal 40, 41 is calibrated to ensure that when the respective pedal 40, 41 is depressed an identical output signal is produced from the signal generating device 120, 140 by both pedals 40, 41 . The output signal from the signal generating device 120, 140 represents the amount and speed of travel which can be achieved in each swing direction when the left pedal 40 and the right pedal 41 are depressed. It is critical to the operation of the heavy equipment that the output signal from the pedal assembly 10 when depressing both pedals 40, 41 is identical.

[0099] The adjustable slide 88 has four slotted openings which allow the adjustable slide 88 to move laterally on the base 81 . The adjustment screw 83 is firstly used to position the adjustable slide 88 so that the crank engaging section 89 engages with the crank mounting arm 61 before the physical rotation stop within the rotary contactor 105 is activated. This will be described in more detail below in relation to the calibration of the pedal assembly 10. As the adjustment screw 83 is screwed into the plug 90, the adjustable slide 88 moves laterally along the base 81 until the crank engaging section 89 is correctly positioned so that the adjustable slide 88 will abut against the crank mounting arm 61 in the correct position to set the movement of each crank 60 and the output from the signal generating device 120, 140. Once the position of each crank 60 has been calibrated by the calibration stops 80 the screws which secure the adjustable slide 88 to the base 81 are tightened and the locking nut 84 is tightened against the mounting block 82 to secure the adjusting screw 83 in position.

[0100] Figs. 16 to 19 show the crank 60 which is connected to opposite ends 116, 117 of the operating shaft 115 and each pedal 40, 41 through the adjustable linkages 50. The crank 60 consists of a cylindrical body 62 and a mounting arm 61 extending perpendicular from one end of the cylindrical body 62. The mounting arm 61 has an opening 66 which receives a fastener to connect an end 52 of the adjustable linkage 50. The outer surface of the cylindrical body 62 is sized to fit and rotate within openings 31 in the side walls 21 , 22 of the housing 20. The cylindrical body 62 at one end has an internal tapered section 64 which corresponds to the tapered ends 116, 117 of the operating shaft 115. The ends 116, 117 of the operating shaft 115 are received within the tapered section 64 and locked therein by key 63A which is located within the corresponding keyway 63 in the cylindrical body 62 of the crank 60. A fastener is inserted through opening 65 in an end of the cylindrical body 62 to secure the crank 60 to threaded sockets centrally located in each end face of the ends 116, 117 of the operating shaft 115. Each crank 60 is mounted on opposite ends 116, 117 of the operating shaft 115 and when viewed from ends 21 , 22 of the housing 20, the mounting arms 62 are positioned diametrically opposite. That is, the mounting arm 62 of the crank 60 mounted adjacent to the side wall 21 is located above the end 117 of the operating shaft 115 and when the left hand pedal 40 is depressed the adjustable linkage 50 attached to the crank 60 will rotate the crank 60 and the operating shaft 115 in an anti-clockwise direction. Likewise, the mounting arm 62 of the crank 60 mounted adjacent to the side wall 22 is located below the end 116 of the operating shaft 115 and when the right hand pedal 41 is depressed the adjustable linkage 50 attached to the crank 60 will rotate the crank 60 and the operating shaft 115 in a clockwise direction. As described above, each adjustable linkage 50 being operable in tension when the respective pedal 40, 41 is depressed.

[0101] Calibration of the heavy equipment pedal assembly 10 is carried out to ensure repeatability in measurement standards for each pedal assembly 10 produced. The position and travel of each pedal 40, 41 is set to produce an identical signal output from the signal generating device 120, 140. In order to calibrate the travel of each pedal 40, 41 the calibration stop 80 mounted on the side walls 21 , 22 of the housing is positioned to set a control reference signal from the signal generating device 120, 140. The control reference signal is identical for both directions of travel. That is, when the left or right hand pedals 40, 41 are depressed the control reference signals produced by the signal generating device 120, 140 are identical for both directions of travel. The position of the calibration stop 80 sets the angular rotation of each pedal 40, 41 to not exceed a pre-determined angular rotation. By way of example, the predetermined angular rotation of each pedal 40, 41 is approximately 150 degrees.

[0102] The adjustable linkages 50 are calibrated before installation to set an identical length for each adjustable linkage 50. The calibration of the adjustable linkages 50 sets the neutral position and rake angle of each pedal 40, 41 so that the rake angle or height of the toe of each pedal 40, 41 above the upper surface 27 of the housing 20 in the neutral position is identical or within ± 1 mm for each pedal 40, 41 . The neutral position and rake angle for each pedal 40, 41 is set with reference to the upper surface 27 of the housing 20. Once the length of each adjustable linkage 50 is set the lock nuts on each rod end of the adjustable linkage 50 is tightened.

[0103] The heavy equipment pedal assembly 10 is calibrated to ensure that when each assembly 10 is installed in the heavy equipment they maintain accuracy, standardisation and repeatability in measurements assuring reliable benchmarks and results. During assembly each pedal assembly 10 is calibrated to meet a set of pre-determined operating parameters as follows:

[0104] Step 1 - Installation of the Signal Generating Device to the Sector Gear Assembly a. With the adjustable linkages 50 connected to each pedal 40, 41 the pedal assembly 10 is turned upside down with the pedals 40, 41 placed on a flat surface to position the pedals 40, 41 in the neutral position; b. The number of teeth on the sector gear rack 153 of the sector gear assembly is visually counted; c. The gear 106 of the rotary contactor 105 is brought into mesh with the sector gear rack 153 of the sector gear assembly 150 in the neutral position and in the mid-position of the sector gear rack 153; d. The pedal assembly 10 is then turned back upright and each pedal 40, 41 is depressed; e. The rotation travel of the sector gear assembly 150 is checked to ensure that it is identical in both directions; and f. The fixing screws which secure the sector gear assembly 150 to the operating shaft 115 are tensioned to secure the sector gear assembly 150 to the operating shaft 115.

[0105] Step 2 - Pedal Contact with Spring Operated Plunger a. Check that each spring operated plunger 100 is in contact or just touching the bottom surface 45 of each pedal 40, 41 when the pedals 40, 41 are in the neutral position; b. If adjustment is required: a. Release the spring operated plunger 100 locking nut and reposition the spring operated plunger 100 so that it is abutting the bottom surface 45 of each pedal 40, 41 ; and b. Tighten the spring operated plunger locking nut. Step 3 - Calibration Stop Adjustment Left Pedal a. Turn the pedal assembly 10 upside down with the pedals 40, 41 on a flat surface and in the neutral position; b. Disconnect the end 52 of the adjustable linkage 50 from both cranks 60 mounted through the side walls 21 , 22 of the housing 20; c. Manually rotate the crank 60 mounted adjacent to the side wall 21 and the sector gear assembly 150 in an anti-clockwise direction until the physical rotation stop of the rotary contactor 115 stops rotation; d. In this position the adjustable slide 88 of the calibration stop 80 mounted on the side wall 21 should just come into contact with the crank 60; e. Rotate the adjustment screw 83 on the calibration stop 80 mounted on the side wall 21 to move the adjustable slide 88 laterally by 1 mm so that the crank engaging section 89 engages with the crank mounting arm 61 before the physical rotation stop within the rotary contactor 105 is activated; f. The calibration stop 80 on the side wall 21 now limits the rotation of the rotary contactor 105 in the anti-clockwise direction; and g. Lock the adjustment screw 83 on the calibration stop 80 mounted on the side wall 21 .

[0106] Step 4 - Calibration Stop Adjustment Right Pedal a. Turn the pedal assembly 10 upside down with the pedals 40, 41 on a flat surface and in the neutral position; b. Manually rotate the crank 60 mounted adjacent to the side wall 22 and the sector gear assembly 150 in a clockwise direction until the physical rotation stop of the rotary contactor 115 stops rotation; c. In this position the adjustable slide 88 of the calibration stop 80 mounted on the side wall 22 should just come into contact with the crank 60; d. Rotate the adjustment screw 83 on the calibration stop 80 mounted on the side wall 22 to move the adjustable slide 88 laterally by 1 mm so that the crank engaging section 89 engages with the crank mounting arm 61 before the physical rotation stop within the rotary contactor 105 is activated; e. The calibration stop 80 on the side wall 22 now limits the rotation of the rotary contactor 105 in the clockwise direction; f. Lock the adjustment screw 83 on the calibration stop 80 mounted on the side wall 22; and g. Reconnect the ends 52 of the adjustable linkages 50 to the cranks 60 mounted through the side walls 21 , 22 of the housing 20.

[0107] Step 5 - Signal Generating Device Output Calibration (Resolver)

[0108] Connect test equipment to the output connector 142 in the electrical connection panel 26 of the panel assembly 10; a. With the pedal assembly 10 in the upright position depress the left pedal 40 and then the right pedal 41 and record the angular rotation from neutral to 100% and the output count value for each pedal 40, 41 ; b. For each pedal 40, 41 the angular rotation or pedal travel must not exceed 150 degrees ± 1 Degree; c. For each pedal 40, 41 the resolver 141 count must be identical for both directions of travel; d. If adjustment is required: a. Loosen the mounting screw on the adjustable mounting bracket clamp 108 holding the resolver 141 and rotate the resolver 141 either clockwise or anti-clockwise until the output count in both directions is identical; b. Retighten the mounting screw on the adjustable mounting bracket clamp 108; and c. Re-check the angular rotation from neutral to 100% to ensure the pedal travel is within tolerance and the counts from the resolver 141 are identical or within 20 counts for both pedals 40, 41 .

[0109] Step 5A - Signal Generating Device Output Calibration (Encoder) a. Connect test equipment to the output connector 122 in the electrical connection panel 26 of the panel assembly 10; b. With the pedal assembly 10 in the upright position depress the left pedal 40 and then the right pedal 41 and record the angular rotation from neutral to 100% and the output count value for each pedal 40, 41 ; c. For each pedal 40, 41 the angular rotation or pedal travel must not exceed 150 degrees ± 1 Degree; d. For each pedal 40, 41 the encoder 121 output count must be identical for both directions of travel; e. If adjustment is required: a. Loosen the fasteners securing the adjustable slide 88 to the base 81 of one of the calibration stops 80 on the side 21 , 22 of the housing 20 of one of the pedals 40, 41 ; b. Release the lock nut 84 on the adjusting screw 83; c. Rotate the adjusting screw 83 in on the plug 90 to reposition the adjustable slide 88; d. Tighten the lock nut 84 on the adjusting screw 83 and the fasteners securing the adjustable slide 88 to the base 81 ; and d. Re-check the angular rotation from neutral to 100% to ensure the pedal travel is within tolerance and the counts from the encoder 121 are identical or within 20 counts for both pedals 40, 41 .

[0110] Step 6 - Tamper Proof Marking a. Thread lock is applied to the fasteners securing the adjustable slide 88 to the base 81 of each calibration stop 80 and the fasteners are tensioned tight with anti-tamper proof paint applied to the heads of each fastener securing the adjustable slide 88 to the base 81 of each calibration stop 80; b. The lock nut 84 on the adjustment screw 83 on each calibration stop 80 is tensioned tight and anti-tamper proof paint is applied to the lock nut 84 of each calibration stop 80; c. Thread lock is applied to each of the fixing screws which secure the sector gear assembly 150 to the operating shaft 115, the fixing screws are then tensioned tight with anti-tamper proof paint applied to the heads of each fixing screw on the sector gear assembly 150; d. Thread lock is applied to the screws securing the base 107 of the rotary contactor 105 to the base plate 111 of the mounting assembly 110 and then tensioned tight with anti-tamper proof paint applied to the heads of each screw on the base 107; e. Each lock nut on each rod end of the adjustable linkages 50 are tensioned tight with anti-tamper proof paint applied to each lock nut of each adjustable linkage 50; f. The lock nut in each spring operated plunger 100 is tensioned tight with anti-tamper proof paint applied to each lock nut on each spring operated plunger 100; and g. Photographs are taken of each of the above components and of the identification tag plates for the pedal assembly 10.

[0111] A method for controlling movement of a boom of a heavy equipment is also described below. The first step is to provide the heavy equipment which has a machine upper portion with a rigid, cable-supported boom extending therefrom. A swing control system and swing motors move the machine upper portion along a path in a swing direction. A pedal assembly 10 is used to actuate the swing movement of the machine upper portion along the path. The pedal assembly 10 has all of the features described above. Each pedal 40, 41 is calibrated as described above prior to installation in the heavy equipment.

[0112] By depressing a first pedal 40 will rotate an operating shaft 115 in a first direction, the rotation of the operating shaft 115 generates a signal from a signal generating device 120. 140 to translate the generated signal into instructions and to transmit the instructions to swing the machine upper portion in the first direction. Releasing the first pedal 40 causes a spring operated plunger 100 positioned on an underside 45 of the first pedal 40 to bias the first pedal 40 toward a neutral position. This also returns the rotary contactor 105 to the normally closed neutral position.

[0113] By depressing a second pedal 41 rotates the operating shaft 115 in a second direction opposite to the first direction. The rotation of the operating shaft 115 generating a signal from the signal generating device 120, 140 to translate the generated signal into instructions and to transmit the instructions to swing the machine upper portion in the second direction. Releasing the second pedal 41 causes a spring operated plunger 100 positioned on an underside 45 of the second pedal 41 to bias the second pedal 41 toward the neutral position. As above, this also returns the rotary contactor 105 to the normally closed neutral position.

[0114] By way of example only, when the left hand pedal 40 is depressed, both the crank 60 and the operating shaft 115 will rotate in an anti-clockwise direction and generate a signal from the signal generating device 120, 140 which represents movement and speed of travel in the left direction and the boom will swing to the left. Likewise, when the right hand pedal 41 is depressed both the crank 60 and the operating shaft 115 will rotate in a clockwise direction and generate a signal from the signal generating device 120, 140 which represents movement and speed of travel in the right direction and the boom will swing to the right. Each adjustable linkage 50 is operated in tension when the respective pedal 40, 41 is depressed.

[0115] ADVANTAGES

[0116] A number of advantages are apparent in the present invention over currently available cantilevered structures, such as those described in the background.

[0117] The present invention provides control for heavy equipment and to pedal assemblies for steering such equipment. In particular, the invention is adapted for steering or controlling an elongate boom for virtually any purpose.

[0118] The adjustable linkages connected to the pedals are designed so that when either pedal is depressed, the adjustable linkages operate in tension, and this affords greater precision of control by the operator than if linkages were operating in compression. This is so because compression links are subject to flexing and failure under pressure compared with linkages in tension which do not flex. The adjustable linkages are adapted to set an identical pitch angle and height for both pedals with respect to the upper surface of the pedal assembly. This saves both time and money by avoiding costly downtime for the heavy equipment.

[0119] The spring operated plungers ensure that if the operator’s feet leave the pedals for any reason the operating shaft is returned to a neutral position where no steering signal is generated. Accordingly the assembly of the subject invention enhances the degree of control and safety in the steering operation.

[0120] The pedal assembly of the present invention avoids costly downtime of the heavy equipment by ensuring each pedal assembly is calibrated to meet a set of pre-determined parameters before installation. The calibration stops allow for accurate positioning of the pedals by limiting the movement of the associated crank and setting a known travel distance for each pedal. The calibration stops are also positioned to prevent the activation of the physical rotation stop of the rotary contactor. This saves both time and money by avoiding costly downtime for the heavy equipment.

[0121] The present invention provides a contactor assembly which is compact and easy to remove while in-situ. By limiting the number of contactor rows to only two rows provides more space within the housing for mounting a larger motion controller. The contactor assembly has also been provided with an internal physical stop tab which prevents the overrun of the contact rows when the pedals are pressed with a greater than normal force. The internal physical stop tabs prevent the over travelling and avoids the contactor assembly from becoming jammed stuck in one direction and causing significant damage to the swing control system and causing personal injury and damage to equipment due to uncontrolled movement.

[0122] VARIATIONS

[0123] It will be realized that the foregoing has been given by way of illustrative example only and that all other modifications and variations as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as herein set forth.

[0124] As used herein the term “and / or” means “and” or “or”, or both.

[0125] As used herein “(s)” following a noun means the plural and / or singular forms of the noun.

[0126] In this specification, adjectives such as first and second, left and right, top and bottom, and the like may be used solely to distinguish one element or action from another element or action without necessarily requiring or implying any actual such relationship or order. Where the context permits, reference to an integer or a component or step (or the like) is not to be interpreted as being limited to only one of that integer, component, or step, but rather could be one or more of that integer, component, or step etc.

[0127] The above description of various embodiments of the present invention is provided for purposes of description to one of ordinary skill in the related art. It is not intended to be exhaustive or to limit the invention to a single disclosed embodiment. As mentioned above, numerous alternatives and variations to the present invention will be apparent to those skilled in the art of the above teaching. Accordingly, while some alternative embodiments have been discussed specifically, other embodiments will be apparent or relatively easily developed by those of ordinary skill in the art. The invention is intended to embrace all alternatives, modifications, and variations of the present invention that have been discussed herein, and other embodiments that fall within the scope of the above described invention.

[0128] In the specification the term “comprising” shall be understood to have a broad meaning similar to the term “including” and will be 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 term “comprising” such as “comprise” and “comprises”.

[0129] Throughout this specification, the words "proximal" and "distal" are intended to refer to a position of a user operating the apparatus. Thus, "proximal", when used with reference to the drawer assembly would relate to that side corresponding to the side of the handle. The word "distal" therefore has an opposite meaning.

[0130] When any number or range is described herein, unless clearly stated otherwise, that number or range is approximate. Recitation of ranges of values herein are intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value and each separate subrange defined by such separate values is incorporated into the specification as if it were individually recited herein.

Claims

CLAIMS1 . A heavy equipment pedal assembly comprising: a housing with a pair of pedals pivotally mounted at a selected spacing to an upper surface of the housing; an operating shaft mounted for rotation within the housing, the operating shaft having a first end spaced apart from a second end; a crank connected to each end of the operating shaft through openings in a respective opposing side walls of the housing, each crank connected to a respective one of the pair of pedals through an adjustable linkage, each adjustable linkage being operable in tension when the respective pedal is depressed; a gear assembly mounted within the housing, the gear assembly is driven by the rotation of the operating shaft; a signal generating device driven by the gear assembly and adapted to translate a generated signal into instructions and to transmit the instructions to actuate a desired movement of the heavy equipment; a calibration stop is located adjacent to each crank, each calibration stop has an adjustable means to set a range of movement of the crank and corresponding rotation of the operating shaft; a spring operated plunger is positioned on an underside of each pedal, the spring operated plunger biasing the associated pedal toward a neutral position; and wherein depression of each respective pedal results in rotation of the operating shaft in opposite directions and the desired movement of the heavy equipment.

2. A heavy equipment pedal assembly as claimed in claim 1 , wherein the signal generating device further comprises a contactor assembly and a motion controller.

3. A heavy equipment pedal assembly as claimed in claim 2, wherein the contactor assembly is a rotary contactor with two or more contact rows.

4. A heavy equipment pedal assembly as claimed in claim 3, wherein the contactor assembly further comprises a physical rotation stop tab, the physical rotation stop tab is adapted to prevent over travel of the contact rows.

5. A heavy equipment pedal assembly as claimed in claim 2, wherein the motion controller is a resolver or an encoder.

6. A heavy equipment pedal assembly as claimed in claim 5, wherein the encoder is an absolute encoder or an absolute encoder with a process field bus interface.

7. A heavy equipment pedal assembly as claimed in claim 1 , wherein each calibration stop comprises: a base mounted on the opposing side walls of the housing; and a slide adjustably mounted to the base, the slide having a crank engaging arm which is adapted to contact the crank to set the movement of the crank and corresponding rotation of the operating shaft.

8. A heavy equipment pedal assembly as claimed in claim 7, wherein each crank has a mounting arm extending perpendicular from a cylindrical body, the mounting arm connecting the crank to each pedal through the adjustable linkage and the cylindrical body is mounted on each end of the operating shaft.

9. A heavy equipment pedal assembly as claimed in claim 8, wherein when mounted on the operating shaft the mounting arm of each respective crank is positioned diametrically opposite on opposing ends of the operating shaft, when each respective pedal is depressed, one of the pair of pedals will rotate the operating shaft clockwise and the other one of the pair of pedals will rotate the operating shaft anti-clockwise.

10. A heavy equipment pedal assembly as claimed in claim 9, wherein when one of the pair of pedals is depressed, the operating shaft will rotate clockwise and generate the signal from the signal generating device to actuate the desired movement and an amount of travel in a first direction, when the other one of the pair of pedals is depressed, the operating shaft will rotate anti-clockwise and generate the signal from the signal generating device to actuate the desired movement and an amount of travel in a second direction.

11. A heavy equipment pedal assembly as claimed in any one of claims 4 to 10, wherein when each pedal is depressed the position of the crank engaging arm of each calibration stop with respect to the mounting arm of each crank is calibrated to set the amount of travel in the first and second directions and prevent the engagement of the physical rotation stop tab of the contactor assembly.

12. A heavy equipment pedal assembly as claimed in claim 11 , wherein each pedal is calibrated to ensure that the amount of travel in the first and second directions produces an identical signal output from the signal generating device.

13. A heavy equipment pedal assembly as claimed in claim 1 , wherein a rotation of each pedal is set to not exceed a pre-determined angular rotation.

14. A heavy equipment pedal assembly as claimed in claim 13, wherein the pre-determined angular rotation is approximately 150 degrees.

15. A heavy equipment pedal assembly as claimed in claim 1 , wherein the adjustable linkage connected to each pedal is adapted to set a height or rake angle position for each pedal with respect to the upper surface of the housing.

16. A heavy equipment pedal assembly as claimed in claim 3, wherein the gear assembly comprises a sector gear extending perpendicular from an operating shaft mounting plate, when the operating shaft is rotated clockwise or anti-clockwise, the sector gear engages with a contact assembly gear to rotate the contactor assembly.

17. A heavy equipment pedal assembly as claimed in claim 1 , wherein a central mounting flange extends from a bottom surface and adjacent to a heel of each pedal, the mounting flange connects each pedal to the respective adjustable linkage and the upper surface of the housing.

18. A heavy equipment pedal assembly as claimed in claim 1 , wherein the operating shaft, the gear assembly and the signal generating device are enclosed within the housing by a removeable cover, the removable cover is positioned on a bottom surface of the housing.

19. A heavy equipment pedal assembly as claimed in claim 18, wherein the operating shaft, the gear assembly and the signal generating device are mounted on a removable base within the housing.

20. A heavy equipment pedal assembly as claimed in claim 1 , wherein the heavy equipment pedal assembly is mounted on an adjustable pivot bracket secured to a cabin floor of the heavy equipment.

21. A heavy equipment pedal assembly as claimed in claim 1 , wherein the heavy equipment pedal assembly is mounted on an adjustable slide rotation bracket on an operator console of the heavy equipment.

22. A heavy equipment pedal assembly as claimed in claim 1 , wherein the desired movement controlled by the heavy equipment pedal assembly is a slewing or swing action.

23. A heavy equipment pedal assembly as claimed in claim 22, wherein the generated signal of the signal generating device controls a swing motor control system to achieve the desired movement and a movement speed of a swing motor.

24. A heavy equipment pedal assembly as claimed in claim 22, wherein the generated signal of the signal generating device controls a pair of proportional valves driving an electro-hydraulic slewing motor to achieve the desired movement and a movement speed of the heavy equipment.

25. A heavy equipment pedal assembly as claimed in claim 1 , wherein the opposing side walls of the housing are overhung by a portion of the upper surface of the housing, and the crank, the calibration stop and the adjustable linkage of each pedal is positioned beneath the overhung portion of the upper surface.

26. A method for controlling movement of a boom of a heavy equipment comprising: providing the heavy equipment having a machine upper portion with a rigid, cable-supported boom extending therefrom, a first drive system having a first motor which moves the machine upper portion along a path in a swing direction; providing a pedal assembly as claimed in claim 1 to actuate the swing movement of the machine upper portion along the path; calibrating each pedal of the pedal assembly to meet a set of predetermined operating parameters; depressing a first pedal to rotate an operating shaft in a first direction, the rotation of the operating shaft generating a signal from a signal generating device to translate the generated signal into instructions and to transmit the instructions to swing the machine upper portion in a first swing direction; releasing the first pedal causes a spring operated plunger positioned on an underside of the first pedal to bias the first pedal toward a neutral position; depressing a second pedal to rotate the operating shaft in a second direction opposite to the first direction, the rotation of the operating shaft generating a signal from the signal generating device to translate the generatedsignal into instructions and to transmit the instructions to swing the machine upper portion in a second swing direction opposite the first swing direction; and releasing the second pedal causes a spring operated plunger positioned on an underside of the second pedal to bias the second pedal toward the neutral position.

27. A method as claimed in claim 26, wherein the pedal assembly comprises any of the features claimed in claims 2 to 25.

28. A pedal assembly that actuates a swing movement of a boom of a heavy equipment, the pedal assembly comprising: a housing with a removeable cover positioned on a bottom surface of the housing, and a pair of pedals pivotally mounted at a selected spacing to an upper surface of the housing; a removable base plate mounted within the housing and adapted to receive an operating shaft mounted for rotation on the removable base, a gear assembly mounted for rotation on the operating shaft, and a signal generating device driven by the gear assembly and adapted to translate a generated signal into instructions when one of the pair of pedals is depressed and to transmit the instructions to actuate the swing movement of the heavy equipment; a crank connected to opposing ends of the operating shaft through openings in opposing side walls of the housing, each crank is positioned diametrically opposite on the opposing ends of the operating shaft and when each respective pedal is depressed, one of the pair of pedals will rotate the operating shaft clockwise and the other one of the pair of pedals will rotate the operating shaft anti-clockwise; an adjustable linkage connects each crank to a respective one of the pair of pedals, each adjustable linkage being operable in tension when the respective pedal is depressed; a calibration stop is located adjacent to each crank, each calibration stop has an adjustable means mounted to a base, the adjustable means having a crank engaging arm which is adapted to contact the crank to set a range of movement of the crank and corresponding rotation of the operating shaft; a spring operated plunger is positioned on an underside of each pedal, the spring operated plunger biasing the associated pedal toward a neutral position when each pedal is no longer depressed; andwherein the pedal assembly is calibrated to meet a set of pre-determined operating parameters.

29. A pedal assembly as claimed in claim 28, wherein the pedal assembly comprises any of the features of the heavy equipment pedal of claims 2 to 25.

30. A pedal assembly as claimed in claim 28 or claim 29, wherein the pedal assembly is calibrated to: set a position of the signal generating device on the gear assembly so that a rotation travel of the gear assembly is identical for travel in both clockwise and anti-clockwise directions; set the height or rake angle of each pedal with respect to the upper surface of the housing to be approximately identical by adjusting the adjustable linkage associated with each pedal; set each spring operated plunger to be in contact with a bottom surface of each respective pedal when each pedal is positioned in the neutral position; set each calibration stop to limit the rotation of the crank and prevent the activation of the physical rotation stop tab of the rotary contactor in both clockwise and anti-clockwise directions; and set the output from the signal generating device to be identical in both the clockwise and anti-clockwise directions.

31. A pedal assembly as claimed in claim 30, wherein once the pedal assembly has been calibrated to meet the set of pre-determined operating parameters, respective locking devices on the gear assembly, the adjustable linkages, the spring operated plungers and the calibration stops are painted with a tamper proof coating to provide an indication to a user of any tampering of components.

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