AU2009238310B2 - An improved hopper discharge door system - Google Patents

Abstract

The present invention relates to an improved material discharge door system and a material discharge container including such a door system. The door system includes a door which is slideably moveable with respect to an opening of the container chute between an open 5 position and a closed position, whereby the opening and the door extend along substantially parallel, declined planes to facilitate gravitational discharge of material and cleaning. The invention further relates to improvements in the means for opening and closing the door, and locking of the door.

Description

14651AU ORIGINAL Complete Specification Applicant: CIMC Rolling Stock Australia Pty Ltd Title: An improved hopper discharge door system Address for Service: LESICAR PERRIN, 49 Wright Street, Adelaide, South Australia 5000, Australia The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 An improved hopper discharge door system The present invention relates to an improved discharge door system for a bulk material handling container. In particular, the present invention relates to an improved discharge door system for a rail wagon grain and mineral sand hopper. 5 BACKGROUND OF THE INVENTION Conventional hopper car discharge door systems include a frame which is fastened to the underside of the hopper. The frame encloses a door slide or gate slide which is permitted to slide horizontally in the frame between the open and closed positions. The door slide has ordinarily been supported within the frame by the use of rollers or metal slide rails. Resilient seals have 10 often been employed to seal the gate tightly in its closed position and prevent the unintentional discharge of materials through the door. A rack and pinion or other mechanical means is typically associated with the upper surface of the moveable door slide to gain a mechanical advantage in sliding the door slide between the open and closed positions. 15 Typical problems associated with horizontal sliding door configurations of this type include: * the retaining of lading on the door slide which adversely affects opening and closing of the door slide; * the collecting of dirt in the racks above the door slide causing jamming; 20 * lading of fine clearance, such as canola or mineral sand, being worked under the seals when the slide door is dragged open, again causing jamming; * the trapping of water on the slide door, which can lead to contamination of lading through mould, and also rusting and corrosion of the door slide, metal rollers, and other metal components; and 25 * occupational health and safety issues resulting from the manual accessibility of the racks and pinions above the door slide.

3 The door slide can be locked firmly in its closed position by the use of a gravity actuated locking pin or the like. There are also known problems associated with the use of such locking pins, including: * the pin can often be bent by way of forced manual opening of the slide door; * the locking mechanisms tend to corrode and jam; * these types of locking systems typically require a special custom made tool for their operation; * unlocking is typically only achievable from one side of, or from underneath, the wagon; and * the locked or unlocked state of the pin is typically viewable from only one side of the wagon. It is therefore an object of the present invention to overcome at least some of the aforementioned problems or to provide the public with a useful alternative. ) SUMMARY OF THE INVENTION In a first form of the invention there is proposed a discharge door system for a bulk material container, said discharge door system including: a chute including a front wall, a rear wall, and two side walls having bottom edges which define an opening which extends in a declined plane such that the front wall bottom edge is disposed higher 5 than the rear wall bottom edge; a door slide disposed in a substantially parallel plane to that of said opening to facilitate gravitational discharge of material above said door slide, said door slide being moveable between an open position in which material is allowed to pass from said chute through said opening, and a closed position preventing material from passing through said opening; 0 a first drive means which when operated moves the door slide between said open and closed positions; a locking means moveable between a first position which prevents the door slide from moving from the closed to the open position, and a second position allowing movement of the door slide from the closed to the open position; a second drive means which when operated moves said locking means between said first and second 5 positions; and whereby operation of said first drive means to open the door slide requires that said second drive means is operated to move the locking means from said first to said second position. Preferably said first and second drive means are first and second air cylinders, whereby air is restricted to said first air cylinder until said second cylinder has been operated.

4 In preference said first and second air cylinders are mounted at the front of the chute, said first cylinder extending in a plane substantially parallel to that of the opening, and said second cylinder extending substantially vertically. In preference a first air cylinder piston is coupled to a connecting arm suspended from beneath 5 the door slide via a vertically extending pin. Preferably said connecting arm includes a horizontal wing portion. Preferably said locking means is in the form of a vertically supported locking key including an abutment surface and a vertically disposed slot, whereby in said first position the abutment surface is located in the path of the horizontal wing portion of the connecting aim, thereby preventing its forward ) motion, and in said second position, the channel is located in the path of the horizontal wing portion of the connecting arm, thereby allowing its forward motion. In preference the second air cylinder piston is coupled to the vertically supported locking key via at least one arm pivotally secured at the front of the chute, said locking key being supported at an end thereof.

5 THIS PAGE INTENTIONALLY BLANK 6 THIS PAGE INTENTIONALLY BLANK 7 BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several implementations of the invention and, together with the description, serve to explain the advantages and principles of the invention. In the drawings: 5 Figure 1 illustrates an underside perspective view of a hopper discharge door system in accordance with the present invention, whereby the slide door is closed and the locking mechanism shown in an enlarged view is in a locked state; Figure 2 illustrates a top perspective view of the hopper discharge door system of Figure 1, whereby the slide door is closed and the locking mechanism shown in an enlarged view is in a locked state; Figure 3 illustrates a front view of the hopper discharge door system of Figure 1, whereby the slide door is closed and the locking mechanism is in a locked state; 8 Figure 4 illustrates a front view of the hopper discharge door system of Figure 1, whereby the locking mechanism is in an unlocked state and the slide door is open; Figure 5 illustrates an underside perspective view of the hopper discharge door system of Figure 1, whereby the locking mechanism shown in an enlarged view is in an 5 unlocked state and the slide door is open; Figure 6 illustrates a top perspective view of the hopper discharge door system of Figure 1, whereby the locking mechanism shown in an enlarged view is in an unlocked state and the slide door is open; Figure 7 illustrates a side view of the hopper discharge door system of Figure 1, whereby 10 the slide door is closed and the locking mechanism is in a locked state; and Figure 8 illustrates a side side view of the hopper discharge door system of Figure 1, whereby the locking mechanism is in an unlocked state and the slide door is open. DESCRIPTION OF THE PREFERRED EMBODIMENTS The following detailed description of the invention refers to the accompanying drawings. 15 Although the description includes exemplary embodiments, other embodiments are possible, and changes may be made to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts. The hopper discharge door system 10 of the present invention is shown in Figures 1-8. In 20 brief, the hopper discharge door system 10 comprises a hopper chute 12, and a slide door assembly 14 and associated locking mechanism 16 positioned substantially at the front of the chute 12. Hopper chute 12 has an angled rectangular opening 18 which allows for gravitational discharge of materials, the front edge of the opening 18 being higher than the rear edge. Hopper 25 chute 12 also include top flanges 20 and 22 for attaching the chute 12 to the underside of a rail wagon hopper or the like (not shown), longitudinal side beams 24 and 26, and a transverse end beam 28 extending there between, for supporting various other components as described below.

9 The slide door assembly 14 includes a frame 30 having side frame members 32 and 34 suspended from an upper lip 36 which lines the sides and the rear of the chute opening 18. The side frame members 32 and 34 accommodate a plurality of rotatable rollers 38, above which is supported a door slide 40 which is free to move between open and closed positions. Figures 1-3 5 illustrate the discharge door system 10 when the door slide 40 is in a closed position, and Figures 4-6 illustrate the discharge door system 10 after the door slide 40 has been opened. The locking mechanism 16 is used to prevent manual opening of the door slide 40, and for safety reasons in connection with automated opening, as will be described in more detail below. 10 The door slide 40 is therefore supported, both in the open and closed positions, between the rollers 38 and the lip 36 which lines part of the opening 18. When door slide 40 is in the closed position the upper surface of the door slide 40 partially seals the opening 18 by maintaining a very fine clearance with lip 36. The skilled addressee should realise the benefits of having an angled opening and sliding 15 door system as described. The door system is essentially self cleaning and self draining by way of gravity in that material is able to run off the angled door slide 40. It is far less likely for material to accumulate, minimising contamination and health issues, and the possibility of product being jammed when the door is dragged open. The front ends of the side frame members 32 and 34 are joined by a transversely 20 extending support member 42 which is suspended from the horizontal end beam 28 by three equally spaced vertical elements 44, 46 and 48. These vertical elements are also used to support parts of the locking mechanism 16, as will become apparent. The door slide assembly 14 further includes a manually actuated operating shaft 50 extending transversely beneath the door slide 40, and held in place between brackets 52 and 54 25 associated with side frame members 32 and 34 respectively. The operating shaft 50 has operating handles 56 and 58 connected to opposed ends thereof, adapted for engagement with a tool (not shown) for engaging and rotating the handles, to enable manual opening and closing of the door slide 40. In particular, the operating shaft 50 is operably coupled to the door slide 40 through a rack and pinion assembly 60.

10 The rack and pinion assembly 60 includes a pair of laterally spaced racks 62 and 64 which are fixed to an underside of the door slide 40. A pair of pinion gears 66 and 68, are slidably received about the operating shaft 50 and have a meshing engagement with the rack members 62 and 64. Thus, the racks 62 and 64 are simultaneously moved in timed relation 5 relative to each other by the pinion gears 66 and 68. The door slide 40 can be opened and closed either manually, as described above using a tool (not shown) to rotate the operating shaft 50 from either side of the rail wagon, or more commonly, by way of an automated method which is described below. The automated method of opening and closing the door slide 40 involves a drive means. 10 In the embodiment shown, the drive means is in the form of a longitudinally extending, actuating air cylinder 70 which is aligned substantially parallel with the plane of the hopper chute rectangular opening 18, and is supported at one of its ends to the front of the hopper chute 12 adjacent the opening 18. A connecting arm 72 is mounted at a first end thereof to the underside of the door slide 40, and extends forwardly at the same angle. The second, opposed end of the 15 connecting arm 72 is coupled to the free end of an internal piston 74 of the actuating air cylinder 70 via connecting pin 76. The skilled addressee would realise that in this configuration, when the piston 74 is in a retracted position, that is, when the piston 74 is positioned inside the air cylinder 70, the door slide 40 is closed. When the air cylinder 70 is actuated to move the internal piston 74 in a 20 forward direction, the connecting arm 72 is also made to move forwardly, thereby shifting the door slide 40 to an open position. In summary, actuation of the air cylinder 70 causes the door slide 40 to open and close. The connecting arm 72 also includes a horizontal wing portion 78 for reasons that will become more apparent below. As mentioned earlier, the opening and closing of the door slide 40 is not possible unless 25 the locking mechanism 16 is disengaged. Turning now to Figures 7-8 in particular, the locking mechanism 16 incorporates the use of a second or locking air cylinder 80 which is supported in a substantially vertical configuration above the transversely extending support member 42 at the front of the hopper chute 12. There are two transversely and generally horizontally extending pivoting arms 82 and 84 30 which are involved in the locking mechanism. In particular, am 82 is pivotally secured at its 11 outer end to vertical element 44, and anm 84 is pivotally secured at its outer end to the opposed vertical element 48. Each arm 82 and 84 then meets at approximately the middle of the chute 12, adjacent the middle vertical element 46, where they are pivotally secured to one another. This connection is reinforced using a latch 86 which is fixed to the middle vertical element 46, 5 through which extends the first arm 82. The internal piston 88 of the locking air cylinder 80 is connected to the first arm 82 at a position adjacent latch 86, so that when the air cylinder 80 is actuated, the internal piston 88 moves upwardly, and the connecting ends of the first and second arms 82 and 84 are made to rotate in an upward direction. Obviously, when the air cylinder 80 is actuated to retract the piston 10 88 inside the cylinder 80, the connecting ends of the first and second arms 82 and 84 are made to rotate in a downward direction. A vertical locking key 90 extends downwardly from the pivotal connection between the first and second arms 82 and 84. Thus, when the connecting arms 82 and 84 are rotated in an upward or downward direction, so is the vertical locking key 90. There is a slot 92 located in the 15 transversely extending support member 42 for maintaining a lower end of the locking key 90 in a vertical configuration whilst still allowing for its vertical movement there through. The various components are arranged in a manner such that when the locking key 90 is in the lower position, it provides an abutment surface 94 in the path of the horizontal wing portion 78 of the connecting arm 72 when air cylinder 70 is actuated. When the locking key 90 is in the 20 upper position, there is a slot or channel 96 provided in the locking key 90 which allows the horizontal wing portion 78 of the connecting arm 72 to pass through when air cylinder 70 is actuated. Therefore, the door system is considered "locked" when the internal piston 88 of air cylinder 80 is in a retracted position and the locking key 90 is lowered to provide an abutment surface 94 for the connecting arm 72. The door system is considered "unlocked" when the 25 internal piston 88 of air cylinder 80 is in an extended position and the locking key 90 is raised to thereby not interfere with the motion of the connecting arm 72. The skilled addressee would realise the benefits of the locking mechanism 16, in that not only is its operation fully automated and operational from within a vehicle cabin (not shown), it allows one to recognise whether the door system is in a "locked" or "unlocked" state more 30 easily, and from either side of the vehicle.

12 Furthermore, the flow of air to each cylinder 70 and 80 is such that unless the locking air cylinder piston 88 is in the extended position, that is, unless the locking key 90 is raised, air is restricted from flowing to the actuating air cylinder 70. Therefore, the door slide 40 cannot be opened or closed using the automated method unless the locking air cylinder 80 has first been 5 actuated and the locking key 90 thereby raised. This is a safety measure which ensures that the door slide 40 cannot be accidentally opened, or forced open, when for example the rail wagon is enroute. The locking mechanism 16 is therefore no longer simply a pin which can be easily bent during manual opening of the door slide 40, as per conventional discharge door systems. The 10 locking mechanism is extremely robust in that the locking key 90 should withstand even the strongest manual attempts at forcing the door slide 40 open. In some situations, for example when a contaminated load is required to be opened under quarantine, it may be necessary to have a means of manually engaging and disengaging the locking mechanism 16. This override means is not shown. 15 The advantages of the present invention should now be apparent. In having an inclined opening 18, not only is the system self cleaning and self draining, it provides more space to apply the manual opening racks 62 and 64 beneath the door slide 40. In being positioned beneath the door like so, the racks 62 and 64 will not collect dirt and thereby jam, manual opening and closing of the door slide 40 can be achieved from either side of the rail wagon, and the system 10 20 becomes generally safer to operate because these moving components are less accessible. The present invention is also advantageous in that it provides an automated method of opening and closing the door slide 40, as well as an automated locking mechanism 16. In "automated mode", the air cylinder 70 is not able to be actuated unless the locking air cylinder 80 has first been actuated, which means that the cylinders can only be operated in sequence. 25 Further advantages and improvements may very well be made to the present invention without deviating from its scope. Although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any 30 and all equivalent devices and apparatus.

13 In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising" is used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention. 5

Claims (7)

1. A discharge door system for a bulk material container, said discharge door system including: a chute including a front wall, a rear wall, and two side walls having bottom edges which define an opening which extends in a declined plane such that the front wall bottom edge is disposed higher than the rear wall bottom edge; a door slide disposed in a substantially parallel plane to that of said opening to facilitate gravitational discharge of material above said door slide, said door slide being moveable between an open position in which material is allowed to pass from said chute through said opening, and a ) closed position preventing material from passing through said opening; a first drive means which when operated moves the door slide between said open and closed positions; a locking means moveable between a first position which prevents the door slide from moving from the closed to the open position, and a second position allowing movement of the door slide 3 from the closed to the open position; a second drive means which when operated moves said locking means between said first and second positions; and whereby operation of said first drive means to open the door slide requires that said second drive means is operated to move the locking means from said first to said second position. 0

2. A discharge door system according to claim 1 wherein said first and second drive means are first and second air cylinders, whereby air is restricted to said first air cylinder until said second cylinder has been operated.

3. A discharge door system according to claim 2 wherein said first and second air cylinders are mounted at the front of the chute, said first cylinder extending in a plane substantially parallel to 5 that of the opening, and said second cylinder extending substantially vertically.

4. A discharge door system according to claim 3 wherein a first air cylinder piston is coupled to a connecting arm suspended from beneath the door slide via a vertically extending pin.

5. A discharge door system according to claim 4 wherein said connecting arm includes a horizontal wing portion. 15

6. A discharge door system according to claim 5 wherein said locking means is in the form of a vertically supported locking key including an abutment surface and a vertically disposed slot, whereby in said first position the abutment surface is located in the path of the horizontal wing portion of the connecting arm, thereby preventing its forward motion, and in said second position, 3 the channel is located in the path of the horizontal wing portion of the connecting arm, thereby allowing its forward motion.

7. A discharge door system according to claim 6 wherein the second air cylinder piston is coupled to the vertically supported locking key via at least one arm pivotally secured at the front of the chute, said locking key being supported at an end thereof. 16 THIS PAGE INTENTIONALLY BLANK 17 THIS PAGE INTENTIONALLY BLANK 18 THIS PAGE INTENTIONALLY BLANK