None.
Not Applicable.
Not Applicable.
1. The Field of the Invention
This invention relates to facilitating powered movement of a load and more particularly, to novel systems and methods for cyclic traveling devices.
2. Related Art
Trucks in various industries have been used for many years to transport material from one location to another. Methods for loading and unloading transported material vary between industries. In many industries, transported material need not be handled with care (i.e. earth, gravel, refuse, and the like). Methods for unloading such materials include dumping, conveying, and ejecting.
Dumping is a popular method for unloading, In general, the dump truck has a frame with a bed or body mounted thereto. Typically, a tailgate forms the rear extreme of the bed. When closed, the tailgate may retain the load within the bed. When open, the tailgate may allow the load to exit the bed. Typically, to facilitate dumping, the bed may be tilted upward. As the bed tilts, the load may flow by gravity out the open tailgate. In other embodiments, the entire truck may be tilted upward to allow the load to flow from the rear of the bed.
In certain applications, dumping may be undesirable. For example, long trucks or trucks with long beds do not lend themselves to safe dumping. Typically, to effectively empty a bed, the truck or the bed must be tilted to at least a forty-five degree angle. As a result, long trucks or beds must be raised to a significant height to dump effectively. Trucks so positioned may be dangerously unstable. They may also be too high to fit under a roof of a location such as a refuse transfer station. Moreover, to accomplish the amount of tilt required, it is common to use telescopic hydraulic cylinders with multiple stages. Staged hydraulic cylinders are significant more costly to purchase and maintain than single stage cylinders.
As an alternative to dumping beds, moving or “live” floors have been incorporated in truck beds. In such configurations, movement of the floor causes the load to flow out the rear end of the bed when the tailgate is open. The movable floors are generally implemented with an endless conveyor belt or a series of moving slats. Movable floors usually require numerous and complex mechanisms that are costly to purchase and maintain. Moreover, for cargo containment, it is difficult to form a movable floor that provides a good seal to the bed. Thus, movable floor beds are limited in the types of materials they may transport.
Ejection unloading is another alternative to dumping. Ejection unloading has found wide acceptance in the refuse industry. Typically, a truck utilizing ejection unloading includes a bed with tailgate forming the rear most extreme of the bed. A movable panel extending upward and across the bed may be placed within the bed to travel back and forth along the length thereof, compacting the load during loading. Hydraulic cylinders are typically used to move the panel. During ejection, the panel is pushed from the front to the rear of the bed, thus driving and unloading the material through the tailgate.
Ejection unloading may be more costly when applied to trucks with comparatively longer beds. Longer beds require that the moving drive panel travel larger distances. As a result, staged hydraulic cylinders are usually employed. Multi-stage hydraulic cylinders are much more expensive to purchase and maintain than single stage hydraulic cylinders.
Moreover, multi-stage hydraulic cylinders, by necessity, consume more radial space than single stage cylinders capable of exerting the same force, which themselves require more axial space. As a result, significantly more bed space (axial cross section) maybe consumed by the staged hydraulic cylinder itself.
To address the space consumption problem of staged hydraulic cylinders, designers have installed staged hydraulic cylinders at an angle with respect to the length of the bed. By installing the cylinder at angle, the length required by the installation may be reduced. However, in an angled installation, only a portion of the resolved force vector exerted by the cylinder is applied to the ejection of the load. As a result, the size or bore of the cylinder must be further increased.
In other applications, pairs of staged hydraulic cylinders have been used. For example, one cylinder may angle across from the driver's side of the bed to the passenger's side of the panel as it extends rearward. A second cylinder may angle across from the passenger's side of the bed to the driver's side of the panel along its length extending rearwardly. Such configurations incorporate the disadvantages of indirect force application and the cost of two telescopic cylinders. In the refuse industry, a load is acquired in small increments, each periodically compacted with a short stroke of a panel or platen. At loading, the required hydraulic stroke for compaction is, or can be, short, but typically occurs along the truck body (bed) at a different location each time. At the end of loading, usually after transporting some distance, the panel or platen must be driven the length of the bed to discharge the load.
What is needed is a device that avoids the various stability, sealing, expense, maintenance, and space consumption problems associated with dumping, moving floors, and ejection unloading. A system is needed also to effectively handle cyclic compaction over a short stroke that may occur at different locations along the bed, while still accommodating a long unloading or expulsion motion of a panel or platen along the full length of a bed.
The present invention may include a cyclic or “inch worm” traveling system. In one embodiment, one or two rails may extend the length of a truck bed. A first slide and a second slide may travel along the rail. In selected embodiments, the rail may have engagement locations spaced there along facilitating engagement of the first and second slides thereto. The invention may include an extension member extending from the first slide to the second slide. The extension member may be positioned so that force may be applied in the direction of travel of a load. A movable panel may be placed in the bed of a trailer or truck. The movable panel may travel along the rail at the impetus of the extension member. Due to the shorter length of the extension member, less of the bed capacity may be consumed by the extension member and movable panel (platen) of the present invention.
In operation, the first slide may engage the rail. The second slide may be selectively positioned to not engage the rail. Thus, as the extension member extends, the second slide may be increasingly spaced from the stationary first slide. Accordingly, the attached movable panel may be advanced toward the rear of the bed to compact a load or to urge a load out past a tailgate. Upon reaching full extension, the second slide may engage an engagement part, bracket, or location on the rail at a preconfigured location. The first slide may then disengage the rail. Thus, as the extension member retracts, it draws the first slide toward the now stationary second slide. Upon complete retraction of the extension member, the first slide may engage an engagement location such as a notch or hole at a preconfigured location. This cycle may repeat.
For a second cycle of travel, the second slide may then disengage the rail again. Thus, as the extension member again extends, the second slide may be increasingly spaced from the stationary first slide. Accordingly, the attached movable panel may be advanced toward the rear of the bed. This cycle may continue along the length of the bed until the entire load has been ejected by the panel or has been compressed. The cycle may be stopped in an intermediate position if a user chooses.
The panel many be retracted in a similar motion, toward the front of the vehicle. Retraction may occur to reset the platen in order to begin loading again. In certain embodiments, a platen or panel may be advanced to a new location as a load fills up and is compacted at a new location. In other embodiments, compaction motions may occur at one “door” or opening near one end of a vehicle until the load is complete and ready for discharge.
Fixed position installations of the present invention may also be constructed, as for use at a landfill or recycling center.
The foregoing features of the present invention will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only typical embodiments of the invention and are, therefore, not to be considered limiting of its scope, the invention will be described with additional specificity and detail through use of the accompanying drawings in which:
It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the system and method of the present invention, as represented in
The present invention may be applied to a variety of applications. Suitable applications may include truck unloading, climbing (such as on a scaffold or ladder), moving loads across a floor, moving loads up an incline, and the like. The following more detailed description of various embodiments is directed to truck unloading, but may easily be adapted to other applications such as scaffold ascension and the like. The devices, rails, engagement stops and other features of all figures may represent the device as installed as such a climbing apparatus.
Referring to
The shape and reinforcement of the slides 12, 14 and rail 16 may be selected to provide a desired structural strength. Additionally, the slide 12, 14 and rail 16 may be shaped to minimize interference with the capacity of the truck bed or other application to which the system 10 may be applied.
Slides 12, 14 and rails 16 in accordance with the present invention may be formed of any suitable material. Suitable materials may include metals, metal alloys, polymers, reinforced polymers, composites, ceramics, wood, and the like. Materials may be selected to provide the desired strength and wear characteristics. Moreover, materials may be selected to provide movement of the slides 12, 14 over the rail 16 without excessive frictional loss.
A rail 16 in accordance with the present invention may have any number of engagement locations 20 distributed there along. Engagement locations 20 or brackets 20 may be any mechanism or formation providing to the first and second slides 1214 the ability to engage the rail 16 and resist further travel there along. The depicted engagement location 20 is a hole. Notches, detents or the like may be used. In certain embodiments, the slides 12, 14, rail 16, and engagement locations 20 may be arranged to resist inadvertent blockage by foreign objects such as trash, earth, gravel, and the like. For example, a slide 12, 14 may be shaped to sweep or push foreign objects from the rail 16 and engagement locations 20. In an alternative embodiment, a slide 12, 14 may be shaped to shear foreign objects caught in their path.
Each of the first and second slides 12, 14 may include on or more stops 22 shaped to engage the engagement locations 20 of the rail. In the depicted embodiment, the stops 22 are shear pins for insertion into the rail 16. In other embodiments, stops 22 are ratchets selectively permitting unidirectional travel of the first or second slide 12, 14 over the engagement locations 20 of the tail 16. In one selected embodiment, the stop 22 may pivot to support a ratcheting motion in both directions along the rail 16.
Stops 22 in accordance with the present invention may be controlled by one or more actuators 24. Actuators 24 may be selected from any devices capable of engaging and disengaging the stops 22 with respect to the engagement locations 20 of the rail 16. Suitable actuators 24 may operate under mechanical motivation, electrical motivation, or any combination thereof. For example, an actuator 24 may be a spring brake actuator extending under pneumatic or hydraulic impetus and retracting under spring impetus. In other embodiments, an actuator 24 may be a solenoid with a return spring or a double-acting solenoid. In one embodiment, an actuator 24 may include two solenoids, one to engage the stop 22 and one to disengage the stop 22.
An extension member 26 may extend from the first slide 12 to the second slide 14. An extension member 26 in accordance with the present invention may be any member capable of controlled extension and contraction. An extension member 26 may operate by hydraulic pressure or any other mechanical or electrical mechanism.
A rail 16 in accordance with the present invention may be shaped or formed in a manner corresponding to the extension member 26. For example, if the extension member 26 is hydraulically operated, the rail may be formed to house, shield, receive, align, dispense or otherwise control the hydraulic hoses that may require access to the extension member 26 at a variety of locations along the rail 16.
A panel 28 may secure to one of the first and second slides 12, 14. The configuration of the panel 28 may vary from application to application. For example, a panel 28 for use in unloading a truck bed may have a height and width corresponding to the truck bed. Thus, as the system 10 propels the panel 28, the contents of the truck bed may be selectively compacted or ejected. If applied to scaffold climbing, the system 10 may include a panel 28 facilitating engagement of a walkway, or the like, to be ascended.
Referring to
Upon reaching maximum extension 29d or an alignment with a selected engagement location 20, the leading slide 14 may engage 29e the rail 16 by stop pin 22B. The trailing slide 12 may disengage 29f from its fixed position to be able to move along the rail 16. Thus, as the extension member 26 retracts, the leading slide 14 is held stationary while the trailing slide 12 advances. The trailing slide 14 may advance in a ratcheting motion or may simply advance to a desired position corresponding to an engagement location 20.
Upon reaching maximum retraction 29g or an alignment with a selected engagement location 20, the trailing slide 12 may engage the rail 16. The leading slide 14 may then disengage the rail 16 and be free to again advance along the rail 16 as the extension member 26 again extends. This process may be repeated 29h until the panel 28 has moved the desired distance. To move in the opposite direction, the designations of leading and trailing slides may be reassigned and the same process may be followed until the panel 28 has returned to the desired location An alternative embodiment is depicted on
In selected embodiments, stops 22 may rotate about a pivot 34. In such an embodiment, an actuator 24 on a slide 12, 14 may rotate a stop 22 to slide on the surface of the rail 16. Upon reaching an engagement location 20, the stop 22 may pivot fully. The stop 22 may be spring biased towards an engaged position. A limiter 36 may control the extent of such pivoting. In an alternative embodiment, the actuator may hold a stop 22 in a neutral position. In such a configuration, rotation of the stop 22 may be accomplished upon reaching an engagement location 20. Such an arrangement may remove the “clicking” noise normally associated with a ratcheting engagement.
A fully pivoted stop 22 may present a ramp 38 in the direction of travel 30 and a block 40 in the opposite direction. The ramp 38 may induce a disengaging rotation of the stop 22 upon contact with the engagement location 20 as the apparatus is extended. Thus, the stop 22 may exit the engagement location in the direction of travel 30. However, the block 40 may resist exit of the stop 22 from the engagement location 20 in a direction opposite to the direction of travel 30.
When travel in the opposite direction is desired, an actuator 24 may rotate the stop 22 to present a ramp 38 in the new direction of travel and a block 40 in the opposite direction. By pivoting the stops 22, the permitted direction of travel and the prohibited direction of travel may be switched.
Referring to
To permit travel in a desired direction 30, a first actuator 24a may be turned off, permitting a first spring 42a to rotate a first stop 22a to a locked position 44a. A second actuator 22b may be turned on to overcome a second spring 42b and rotate a second stop 22b to an unlocked position 46. Similarly, a third actuator 24c may be turned off, deactivated, or otherwise disengaged, permitting a third spring 42c to rotate a third stop 22c to a locked position 44b; A forth actuator 22d may be activated, engaged, operated, or switched on to overcome a forth spring 42d and rotate a forth stop 22d to an unlocked position 46b. Abutments 48 may be provided to generate interference between the stops 22a, 22c and the rail 16.
To permit travel in the opposite direction, actuators 22b, 22d that were activated or turned on may be deactivated or turned off, and actuators 22a, 22c that were deactivated (turned off) may be turned on reactivated. Slots 25 may be provided in the stops 22a, 22b, 22c, 22d to provide proper clearances and rotation.
Referring to
Referring to
Referring to
Referring to
In selected embodiments, both packing and ejection cycles may be incorporated in a control system. A packing cycle may be a single extension and retraction of the extension member 26 wherein one of the slides 12, 14 never relocates on the rail 16. If more extensive packing is desired, particularly in mostly empty beds, packing cycles may involve travel of the system 10. An ejection cycle may include multiple extensions and retractions of the extension member 26 until the panel 28 pushes all material from the bed.
Packing cycles may be used in the refuse industry to compact trash and clear space for more trash. Packing cycles may be relatively rapid since the entire system 10 may not have to travel. That is, the panel 28 may simply clear an entrance region for inputs of refuse, compacting only as necessary therefore. Once the bed is full, an ejection cycle may push the entire load of trash from the bed.
In a packing cycle for one embodiment, a first solenoid 50 may be energized and a four-way, three-position valve 52 may shift. As a result, the extension member 26 may retract. When a “pack” momentary contact switch 54 is depressed, a first relay 56 may be energized, a first contact 58 may be closed, and a second contact 60 may be opened. A second solenoid 62 may then be energized and the first solenoid 50 may be deactivated. This may cause the four-way, three-position valve 52 to shift, resulting in the extension of the extension member 26.
An extension limit switch 64 may be closed and remain closed until the extension member 26 reaches maximum extension. A double pole, retraction limit switch 66 may have a first pole 68 and a second pole 70. The first pole 68 may be initially closed and the second pole 70 may be initially open. As the extension member 26 begins to extend, the double pole, retraction limit switch 66 shifts and the first pole 68 may open while the second pole 70 may close.
In the packing cycle, a third solenoid 72 may be energized and a first three-way, two-position valve 74 may shift, applying pressure to an actuator 24a located on the leading slide. Thus, while the rear stop remains engaged to anchor the apparatus, the lead slide is freed so that the platen may be driven to pack the material.
At any time during extension, the “retract” momentary contact switch 76 may be depressed. This may open the first contact 58 and close the second contact 60. Thus, the first solenoid 50 may be activated while the second solenoid 62 is deactivated. With the first solenoid 50 active, the four-way, three-position valve 52 may shift and the extension member 26 retract.
If the packer mode is allowed to run, the extension member 26 may fully extend, the extension limit switch 64 may open, and the first relay 56 may become inactive. This may open the first contact 58 and close the second contact 60, thereby, energizing the first solenoid 50 and deactivating the second solenoid 62. With the first solenoid 50 active, the four-way, three-position valve 52 shifts, the extension member 26 retracts, and the extension limit switch 64 closes. When the extension member 26 retracts completely, the retraction limit switch 66 may shift and the first pole 68 may close while the second pole 70 opens. Thus, a pack cycle may be completed and both the first and second solenoids 50, 62 may be left inactive.
In certain embodiments, the control system may also support an ejection mode. To eject, a mode switch 78 may be switched from “pack mode” to “eject mode.” Similarly, a direction switch 80 may be set for “eject.” At such settings, a second relay 82 may be energized, a third contact 84 may open, and a forth contact 86 may close. A fourth solenoid 88 and the third solenoid 72 maybe energized. As a result, a second three-way, two-position valve 90 as well as the first three-way, two-position valve 74 may shift to apply pneumatic pressure to the actuators 24a, 24b.
The first relay 56 may be energized, the first contact 58 may be closed, and the second contact 60 may be opened. As a result, the second solenoid 62 may then be energized while the first solenoid 50 is deactivated. This may cause the four-way, three-position valve 52 to shift, resulting in the extension of the extension member 26.
As the extension member 26 extends, the extension limit switch 64 may remain closed until full extension is achieved. The first pole 68 of the double pole, retraction limit switch 66 may be initially closed and the second pole 70 may be initially open. As the extension member 26 begins to extend, the retraction limit switch 66 may shift and the first pole 68 open while the second pole 70 closes. When the extension member 26 reaches maximum extension, the extension limit switch 64 may open and the first relay 56 may become inactive. This may open the first contact 58 and close the second contact 60. Thus, the first solenoid 50 may be energized while the second solenoid 62 may be deactivated.
With the first solenoid 50 active, the four-way, thee-position valve 52 may shift causing the extension member 26 to retract and the extension limit switch 64 to close. When the extension member 26 retracts completely, the cycle may begin again and continue until the direction switch 80 is moved to “uneject.” The direction switch 80 may be toggled manually or triggered by reaching the end of the rail 16.
In the “unejected” direction, a second relay 82 may be energized, a third contact 84 may open, and a forth contact 86 may close.
A forth solenoid 88 as well as the third solenoid 72 may be deactivated causing a second three-way, two-position valve 90 as well as the first threeway, two-position valve 74 to release pressure from the actuators 24a, 24b. The extension member 26 may continue in the cycle of extension and retraction as outlined hereinabove. Because the stops 22 have rotated into engagement, the system 10 begins to move forward.
Referring to
A cyclic traveling system 10 may also eject the load from a front-loading refuse truck 92. When the body 96 is full, a tailgate 98 may be opened permitting the load to be ejected from the rear of the body 96.
Referring to
Referring to
In certain embodiments, the slot spacing 110 of engagement locations 20 may be slightly greater than the spacing closed tooth 112 of the teeth 22 when the extension member 26 is retracted. In one example, if the closed tooth spacing 112 is 17 inches, the slot spacing 110 may be 18 inches equal to the closed tooth spacing 112 of the teeth 22 when the extension member 26 is retracted plus one inch.
In certain embodiments, the stroke length 114 of the extension member 26 may be slightly greater than the closed tooth spacing 112 of the teeth 22 when the extension member 26 is retracted. In one example, the stroke length 114 of the extension member 26 may be selected or adjusted to be three inches longer than the closed tooth spacing 112 of the teeth 22 when the extension member 26 is retracted.
In general, the smaller the closed tooth spacing 112 of the teeth 22 when the extension member 26 is retracted, then the greater number of cycles may be needed to reach the end of the rail 16. As a result, travel time may be increase. On the other hand, the larger the closed tooth spacing 112 of the teeth 22 when the extension member 26 is retracted, the fewer number of cycles may be needed to reach the end of the rail 16, thus shortening travel time. However, the apparatus space is increased and available load space correspondingly decreased.
When there are more engagement locations 20 on the rail 16 than may be necessary, the process of alignment may be simplified. If a stop 22 does not align with an engagement location 20, then, when the extension member 26 begins to extend or contract, the misaligned stop 22 will slide back along the rail 16 until proper engagement is acquired at a next shorter stop. The travel lost due to sliding stops 22 may, however, increase the cycle time of the system 10.
Formulas and Relations:
One embodiment of the present invention is dimensioned according to these formulas:
Closed Tooth Spacing 112+Stroke 114≧2 * Slot Spacing 110
This places lead tooth into advance slot 200 with a reasonable tolerance.
Slot Length 108≧Tooth length 106
Slot Spacing 110≧Closed Tooth Spacing 112
Again these dimensions maintain a tooth slot engagement tolerance that is durable and robust, but does not sacrifice any unreasonable amount of throw length. In one embodiment, Slot length=Tooth length+2 inches.
The Stroke Length, Closed Tooth Spacing and Slot Spacing have direct relationship. If Slot Spacing were greater than Closed Tooth Spacing by too much, 2″ or more in the example embodiment herein described, the invention does not place the tooth exactly into the next slot. When Slot Spacing is less than Closed Tooth Spacing by 2″ or more, the invention also does not place the tooth exactly into the next slot. When the Slot Spacing is equal to the Closed Tooth Spacing, the invention does not reliably place the tooth exactly into the next slot. Accordingly, an ideal relationship in the example embodiment is that the Slot Spacing=Closed Tooth Spacing+1 inch.
If the Stroke Length in the example dimensions were greater than the Closed Tooth Spacing by 4″ or more, the “dog” tooth would surpass the next needed slot. However the “dog” tooth would be brought back into the correct slot as the cylinder retracts. The cycle time would increase because of how much extra travel the “dog” tooth does in order to be positioned in the next slot. If the Stroke Length is less than or equal to the Closed Tooth Spacing, the invention would not place the tooth exactly into the next slot. The ideal stroke length needs to be 3″ greater than the Closed Tooth Spacing, relative to dimensions in the example.
Accordingly, Stroke Length=Closed Tooth Spacing+3. The closed tooth spacing is related to the length of the track such that a smaller closed tooth spacing creates a larger number of cycles needed to reach end of track and longer amount of time to empty body. Longer Closed Tooth Spacing means a shorter amount of time to empty body.
When there are more slots in the track than needed different relations of the above equations may be allowed. The “dog” teeth will not be placed in the next slot exactly, but will fall back into a previous slot. The cycle time is increased. The number of slots needed in the track is increased.
To place the “dog” tooth in the middle of the slot in both the ejecting and retracting:
1. Pick a Stroke Length
2. Pick a Gap (X)
3. Use these equations:
Stroke−3* X=ClosedToothSpacing
SlotSpacing=ClosedToothSpacing+X
In operation, as illustrated in
In the beginning or rest position depicted in
Upon engagement of the extending cylinder 26, the load is pushed forward, to the right in
In operation a next step will be for the apparatus to draw its rear tooth forward or to the right in
Upon a next extending cycle, extension of the cylinder will drive the rear tooth 22A rearwards until its rear engaging face 25A contacts a rear engaging face 23B of second slot 20B. This engagement will provide the resistance against which the now vertically retracted front tooth 22B, as well as the load, can be displaced forward another step. This cycle repeats until the load is either compressed or disposed of.
In order to retract the apparatus to its original rest position so that the garbage truck or other haul vehicle is open and ready for reloading, the process is essentially reversed.
Of course, various embodiments of the present invention, and the position of the apparatus is selectable so that an operator can stop the apparatus in any slot. This allows the operator to open the haul vehicle cargo space door, and eject from it or leave the door closed and compress a load against it to whatever degree is necessary.
The gaps and tolerances disclosed herein are an efficient embodiment of the present invention, particularly as it is applied in haul trucks such as garbage trucks. Other relative dimensions remain within the scope of the present invention. Of course the apparatus of the present invention may be dimensioned in other sizes in order to perform work of a larger capacity, as for example in mining, or for smaller capacity. Normalization of the dimensions given in the example above yield a scaleable efficient embodiment characterized by the following ratios and preferred ranges.
In view of the foregoing, it will be seen that the several advantages of the invention are achieved and attained.
The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.
As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.