AU2014233583B2 - A traction mechanism for a conveyor belt roller replacer - Google Patents

Abstract

A traction mechanism 10 for a rail-going vehicle 5 is provided, the traction mechanism 10 having an actuator 12 for operative fitment to the vehicle 5 proximate a rail engaging assembly 6 of the vehicle. The traction mechanism also includes an engager 14 linked to the actuator 12 and configured to engage the rail 8 when actuated from an idle position into an active position by the actuator 12. When the engager 14 is in the active position, the engager 14 increases traction of the rail engaging assembly 6 on the rail 8.

Description

1 TITLE OF INVENTION A Traction Mechanism for a Conveyor Belt Roller Replacer. TECHNICAL FIELD [0001] This invention relates to a traction mechanism for a conveyor belt roller replacer and to such a replacer device including a traction mechanism. BACKGROUND ART [0002] The following discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application. [0003] Belt conveyors are generally used for materials handling and transportation. In particular, belt conveyors are commonly used for transportation of particulate materials; for example, in mining and grain-handling applications. [0004] A belt conveyor typically comprises an endless conveyor belt passing around end rollers to define an upper load-carrying run and a lower return run. The upper and lower runs are supported at intervals by a series of idler roller sets. Each roller set usually includes two or more idler rollers disposed in an end-to-end relation and positioned to engage the underside of the respective run effectively distributing a downward force of the conveyor belt between the 2 rollers. Where the load carrying run is of a trough configuration, the idler roller sets each typically comprise a horizontal central roller and two inclined side rollers on opposed ends of the central roller arranged to guide the trough configuration of the belt between them. In this manner, material to be transported can be supported in the trough formed by the conveyor belt. [0005] There is generally a need to change such idler rollers over time, such as when they become defective or wear out. The procedure, which is sometimes referred to as a roller change out, typically entails stopping the conveyor, getting access to the rollers by, for example, lifting the section of the conveyor belt at which the defective idler roller is located from the rollers to provide access to the roller, removing and replacing the defective roller, and then returning the lifted section of the conveyor belt to the original position so that it is supported on the replacement roller. In certain circumstances, it may also be necessary to remove the material being carried on the conveyor belt in order to access the rollers supporting the belt. [0006] Accordingly, it is often necessary that operation of the belt conveyor be stopped so that the belt is stationary during the roller change-out procedure. The requirement to stop operation of the belt conveyor can lead to significant losses, both in terms of time and production opportunities. For example, in a mining environment, movement of product on a conveyor may translate to thousands of dollars per hour, with a stoppage of any number of minutes equating to significant production losses. [0007] Conventionally, the roller removal and replacement step in the roller change-out procedure is typically performed 3 manually. This can be disadvantageous, as it requires use of trained personnel, can also be time consuming and may expose personnel to hazardous working positions. Stopping operation of a conveyor is particularly important where a roller change out is done manually, as it forms a major safety concern for the personnel performing the roller change-out. [0008] It is against this background, and the problems and difficulties associated therewith, that the present Applicants have developed a conveyor belt roller replacer device to address such shortcomings and this device is described in WO/2013/138841 and AU2012258296 to the same Applicants, the contents of which are incorporated herein by reference. [0009] The following invention is associated with the device described in the aforementioned applications and the object of the current invention is to ameliorate the practical application and operation of such a replacer device. SUMMARY OF INVENTION [0010] According to a first aspect of the invention there is provided a traction mechanism for a rail-going vehicle, said traction mechanism comprising: an actuator for operative fitment to the vehicle proximate a rail engaging assembly of the vehicle; and an engager linked to the actuator and configured to engage the rail when actuated from an idle position into an active position by the actuator, wherein when in the active position, the engager increases traction of the rail engaging assembly on the rail.

4 [0011] It is to be appreciated that reference to a 'rail engaging assembly' includes any mechanism or construct via which the replacer device operatively engages the rail, such as a wheel or roller assembly sitting on the rail, a wheel or roller assembly suspended from the rail, a wheel or roller assembly mounted to the rail, a low-friction slider arrangement mounting the replacer device to the rail, and/or the like. [0012] Typically, the actuator is configured to actuate the engager with varying degrees of force so that the amount of traction produced when in the active position is selectively variable. [0013] Typically, the actuator is selected from a list comprising a hydraulic actuator, a pneumatic actuator, an electromechanical actuator, and an electromagnetic actuator. [0014] Typically, the engager includes a roller arranged in a cam-follower manner with an underside of a transverse portion of the rail, so that the roller is able to roll along the underside of the transverse portion as the replacer device traverses the rail whilst able to increase traction at the same time. [0015] Typically, the engager includes a pair of rollers arranged on opposite sides of a central portion of the rail. [0016] Typically, the engager is linked to the actuator by means of a connecting rod via which the actuator is able to exert force on the engager to displace the engager between the idle and active positions.

5 [0017] Typically, the traction mechanism includes guide rollers configured to engage a ridge portion of the rail to align the engager with the rail in both the idle and active positions. [0018] According to a second aspect of the invention there is provided a traction mechanism for a conveyor belt roller replacer device which includes at least one rail engaging assembly operatively associated with a rail via which the replacer device is able to traverse a length of a belt conveyor, said traction mechanism comprising: an actuator for operative fitment to the replacer device proximate a rail engaging assembly; and an engager linked to the actuator and configured to engage the rail when actuated from an idle position into an active position by the actuator, wherein when in the active position, the engager increases traction of the rail engaging assembly on the rail. [0019] It is to be appreciated that reference to a 'rail engaging assembly' includes any mechanism or construct via which the replacer device engages the rail, such as a wheel or roller assembly sitting on the rail, a wheel or roller assembly suspended from the rail, a wheel or roller assembly mounted to the rail, a low-friction slider arrangement mounting the replacer device to the rail, and/or the like. [0020] Typically, the actuator is configured to actuate the engager with varying degrees of force so that the amount of traction produced when in the active position is selectively variable.

6 [0021] Typically, the actuator is selected from a list comprising a hydraulic actuator, a pneumatic actuator, an electromechanical actuator, and an electromagnetic actuator. [0022] Typically, the engager includes a roller arranged in a cam-follower manner with an underside of a transverse portion of the rail, so that the roller is able to roll along the underside of the transverse portion as the replacer device traverses the rail. [0023] Typically, the engager includes a pair of rollers arranged on opposite sides of a central portion of the rail. [0024] Typically, the engager is linked to the actuator by means of a connecting rod via which the actuator is able to exert force on the engager to displace the engager between the idle and active positions. [0025] Typically, the traction mechanism includes guide rollers configured to engage a ridge portion of the rail to align the engager with the rail in both the idle and active positions. BRIEF DESCRIPTION OF DRAWINGS [0026] Features of the present invention are more fully described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. The description will be made with reference to the accompanying drawings in which: 7 Figure 1 is a perspective view of an embodiment of a traction mechanism for a conveyor belt roller replacer device; Figure 2 is a side view representation of the traction mechanism of Figure 1; Figure 3 is a front view representation of the traction mechanism of Figure 1 with the mechanism in an idle position; Figure 4 is a sectional representation of the mechanism along line A-A shown in Figure 3; Figure 5 is a front view representation of the traction mechanism of Figure 1 with the mechanism in an active position; and Figure 6 is a sectional representation of the mechanism along line B-B shown in Figure 5. DESCRIPTION OF EMBODIMENTS [0027] The following description provides examples of different embodiments of a traction mechanism generally indicated by reference numeral 10 for a rail going vehicle, such as a conveyor belt roller replacer device (not shown in detail). As mentioned earlier in this specification, an example of a roller replacer device is described in detail in WO/2013/138841 and AU2012258296 to the same Applicants and the reader is referred thereto if additional context is required. [0028] In essence, the replacer device, a part of which is generally indicated herein by reference numeral 5, is configured to travel on a track comprised of two rails running on either side of a belt conveyor system. The device is capable of lifting a conveyor belt off the belt conveyor 8 whilst the conveyor is in motion and then to replace any worn or damaged idler rollers underneath a lifted portion of the belt, before returning the belt onto the idler rollers. [0029] However, as the device is capable of automated operation and belt conveyors can span hundreds of metres to kilometres over varying terrain, it is often necessary to drive the replacer device along the track which is at an incline or decline, e.g. when the belt conveyor spans across uneven terrain. In addition, given the nature of the operation of the device, it is vitally important that the device is securely fixed to the track whilst in operation, specifically when in operation at an incline or decline. As such, the current traction mechanism was specifically developed for this task and examples thereof will now be discussed with particular reference to the accompanying drawings. [0030] Figure 1 shows an example of the traction mechanism 10. A leg of the replacer device 5 is shown, which includes a rail engaging assembly in the form of a wheel block assembly 6 via which the device 5 sits on a rail 8. The wheel block assembly 6 includes a housing, as shown, within which a wheel 6.1 is located and which, in turn, engages the rail 8. The wheel block 6 may also feature some manner of propulsion mechanism for driving the wheel 6.1, such as an electric motor, or the like. [0031] It is to be appreciated that various different configurations may occur for the rail engaging assembly via which the device 5 engages with the rail 8. For example, in one example the device 5 may be suspended from the rail 8, or the device may have a wheel or roller assembly which engages a side of the rail, or the device may have some manner of low friction arrangement which attaches it to the rail, including 9 a magnetic levitation arrangement, or the like. Different rail configurations are well known in the art and all form part of the manner in which the device 5 may engage the rail, depending on operational or situational requirements, etc. [0032] The traction mechanism 10 includes an actuator 12 which is fitted or attached to the replacer device 5 proximate the wheel block 6 in the current example. Depending on the configuration of the wheel block 6, the traction mechanism 10 may be attached differently and/or at a different location than the one exemplified, but such variations are understood to fall within the scope of the current invention. [0033] The actuator 12 may include any suitable actuator which is able to push or pull the engager 14, as will be described in more detail below, in order to produce a necessary clamping force required by the mechanism 10 to increase traction when in the active position. Accordingly, the actuator 12 may include a hydraulic actuator, a pneumatic actuator, an electromechanical actuator, an electromagnetic actuator and/or any other suitable actuator. It is further to be appreciated that, in other examples, the actuator 12 may displace the engager 14 differently, i.e. not in a push-or pull manner, such as arcuately, elliptically, obliquely, or the like. [0034] The traction mechanism 10 further includes an engager 14 which is linked to the actuator 12 and is configured to engage the rail 8. The engager 14 is generally displaceable between an idle position, in which it does not engage or clamp the rail 8, and an active position, in which it does. Figures 3 and 4 show an example of the engager 14 in the idle position, with Figures 5 and 6 showing the same configuration 10 but with the engager 14 in the active position engaging the rail 8 to clamp the wheel block 6 to the rail 8. [0035] In the current example, the rail 8 includes a number of portions, which are best distinguished when viewing the rail 8 in cross-sectional side view as shown in Figure 3. From such a perspective, the rail 8 defines an I-section which includes a central portion 8.1 flanked on either ends by transverse portions 8.2. [0036] In the current example, the wheel block 6 typically engages an upper transverse portion 8.2, as shown. However, it is to be appreciated that in other examples, a different engagement may be appropriate. In addition, this transverse portion 8.2 defines a ridge portion 8.3 thereon to facilitate engagement with the wheel 6.1 of the wheel block 6, i.e. the wheel 6.1 defines a circumferential groove within which the ridge portion 8.3 sits when in operation. As can be seen in Figure 2, the wheel 6.1 straddles the ridge portion 8.3 without contacting an upper surface of the upper transverse portion 8.2. However, the wheel 6.1 may ride on this upper surface of the transverse portion 8.2 in other examples. [0037] In this example, the engager 14 takes the form of two displaceable rollers linked to the actuator 12 and located on either side of the central portion of the rail 8.1, as shown. However, it is to be appreciated that the engager 14 may take other forms and/or shapes, such as friction blocks, etc. The engager rollers 14 are typically linked to the actuator 12 by means of respective connecting rods 20. The rollers are configured to fit underneath the transverse portion of the rail 8.2, as shown. In the idle position, the engager rollers 14 do not come into contact with any portion of the rail 8. However, when the actuator 12 actuates the engager rollers 14 11 from the idle position into the active position, the engager rollers 14 pulls the wheel block 6 towards the transverse portion of the rail 8.2, effectively producing a clamping effect to increase the traction of the wheel block 6 on the rail 8. [0038] In this manner, the replacer device 5 is selectively securable to the rail 8 depending on the state of the actuator 12, i.e. the increased traction can be used to prevent slipping of the replacer device when traveling up or down and incline/decline through various levels of force applied by the engager rollers 14 to the rail. It is also to be appreciated that by increasing the force produced by the actuator 12, it is possible to secure the replacer device to the rail 8 so that it remains largely stationary on the rail 8. [0039] In the current example, the traction mechanism 10 also includes guide rollers 16 fixed to an associated guide housing 18 attached to the actuator 12, as shown. The guide rollers 16 are generally configured to engage the ridge portion of the rail 8.3 to align the engager rollers 14 with the rail 8 in both the idle and active positions. This ensures that the traction mechanism 10 is correctly aligned to effectively increase traction or when securing the device 5 to the rail 8. [0040] As mentioned above, Figure 4 shows the traction mechanism 10 with the engager 14 in the idle position, with Figure 6 showing the engager in the active position engaging the rail 8 and producing a clamping effect to secure the device 5 to the rail. The letter "L" is used to indicate the distance between the engager roller 14 and an underside of the transverse portion 8.3 of the rail 8. In the idle position, 'L' is larger than zero. When the actuator 12 is active and pulling the engager rollers 14 against the underside of the 12 rail 8.3, the distance "L" has been decreased to zero and the traction mechanism 10 produces a clamping force to increase the traction of the wheel block 6 on the rail 8. [0041] As such, the actuator 12 is typically under control of a control system (not shown) of the replacer device 5, so that when this control system senses that the replacer device 5 is traveling up or down and incline or decline, the control system activates the actuator 12 accordingly to produce the necessary force to prevent slippage of the device 5 on the rail 8 as it travels up or down the incline or decline. It is to be appreciated that, depending on the amount of force produced by the actuator 12, the replacer device 5 may be mobile or held stationary with the engager 14 in the active position. [0042] Similarly, when this control system senses that the replacer device 5 is in a desired position on the rail 8, the control system is able to activate the actuator 12 to produce sufficient force in order to clamp the replacer device 5 securely to the rail 8 so that it remains stationary. This finds particular application where the replacer device 5 is to be secured on a rail having an incline or decline. [0043] As mentioned, an advantage of the current example is that the control system is able to gradually increase or decrease the clamping force produced by the traction mechanism 10 by varying the level of force produced by the actuator 12. The ability of the engager rollers 14 to engage and roll alongside the underside of the rail 8.3 also assists in this regard. This is particularly useful if the replacer device 5 is driven up an incline or down a decline and minor adjustments in a position of the device is required. Once the device 5 reaches the desired position on the rail, the 13 actuator 12 can be fully engaged and the resultant clamping force or traction force produced will secure the device on the rail, even if at an incline or decline. [0044] It should be appreciated that the scope of the invention is not limited to the scope of the embodiment described. Various modifications and improvements may be made to the embodiment described without departing from the scope of the invention. [0045] Throughout this specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. [0046] It is to be appreciated that reference to "one example" or "an example" of the invention is not made in an exclusive sense. Accordingly, one example may exemplify certain aspects of the invention, whilst other aspects are exemplified in a different example. These examples are intended to assist the skilled person in performing the invention and are not intended to limit the overall scope of the invention in any way unless the context clearly indicates otherwise. CITATION LIST Patent literature WO/2013/138841 (SANDPIT INNOVATION ET AL) available 26 September 2013; AU2012258296 (SANDPIT INNOVATION ET AL) available 10 October 2013.

Claims (8)

1. A traction mechanism for a conveyor belt roller replacer device which includes at least one rail engaging assembly operatively associated with a rail via which the replacer device is able to traverse a length of a belt conveyor, said traction mechanism comprising: an actuator for operative fitment to the replacer device proximate a rail engaging assembly; an engager linked to the actuator and configured to engage the rail when actuated from an idle position into an active position by the actuator, wherein when in the active position, the engager increases traction of the rail engaging assembly on the rail; and a control system configured to operatively sense an orientation of the replacer device on the rail and for dynamically controlling the actuator so that the amount of traction produced when in the active position is selectively variable by the control system according to the sensed orientation.

2. The traction mechanism of claim 1, wherein the actuator is selected from a list comprising a hydraulic actuator, a pneumatic actuator, an electromechanical actuator, and an electromagnetic actuator.

3. The traction mechanism of claim 1, wherein the engager includes a roller arranged in a cam-follower manner with an underside of a transverse portion of the rail, so that the roller is able to roll along the underside of the transverse portion as the replacer device traverses the rail. A A I1-XTr'%1F-7h OTTflrT-P 15 X Received 21/08/2014

4. The traction mechanism of any one of claims 1 to 3, wherein the engager includes a pair of rollers arranged on opposite sides of a central portion of the rail.

5. The traction mechanism of any one of claims 1 to 4, wherein the engager is linked to the actuator by means of a connecting rod via which the actuator is able to exert force on the engager to displace the engager between the idle and active positions.

6. The traction mechanism of any one of claims 1 to 5, which includes at least one guide roller configured to engage a ridge portion of the rail to align the engager with the rail in both the idle and active positions.

7. The traction mechanism of any one of claims 1 to 6, wherein the control system is configured to control the traction to prevent slippage of the replacer device as it travels up or down an incline or decline.

8. The traction mechanism of any one of claims 1 to 7, wherein the control system is configured to control the traction to clamp the replacer device securely to the rail when in a desired position. A A I1-XTr'%1F-7h OTTf7TlrT