Trailer-mounted conveyor system and method

A live-bottom trailer having a conveyor system. The conveyor system including: a frame; a conveyor mounted to the frame and having a carrying surface and an opposite rear surface, the conveyor operable to move the carrying surface between a first end of the live-bottom trailer and a second end of the live-bottom trailer while the rear surface passes over a support surface of the frame; and a pressurized air system operable to direct pressurized air at the rear surface of the conveyor to reduce friction between the support surface of the frame and the rear surface of the conveyor.

FIELD

The specification relates generally to a conveyor system, and more specifically to a trailer-mounted conveyor system.

BACKGROUND

United States Pat. App. Pub. No. 2004/0118661 to Swinderman et al. (“Swinderman”) purports to disclose a multipressure plenum system for supporting a conveyor belt of a gas supported belt conveyor and a method of operation. Swinderman further purports to disclose that the multipressure plenum system includes a multipressure plenum having a support surface including a plurality of apertures and a chamber in fluid communication with the apertures. Swinderman purports to disclose that the chamber of the plenum is in selective fluid communication with a first source of gas at a first pressure, and is in selective fluid communication with a second source of gas at a second pressure. Swinderman purports to disclose that gas from the first source of gas at the first pressure flows through the apertures in the plenum to form a gas cushion which supports the conveyor belt above the plenum, and gas from the second source of gas at the second pressure selectively flows through the apertures in the plenum to provide additional support to the conveyor belt.

U.S. Pat. No. 10,781,047 to Warmoth et al. (“Warmoth”) purports to disclose air-supported belt conveyors and independent conveyor subsystems that are selectively and independently designed to meet requirements that can change along the length of a conveyor, as well as from conveyor to conveyor.

U.S. Pat. No. 3,756,380 to Ackroyd et al. (“Ackroyd”) purports to disclose a conveyor having an air cushion supported endless belt wherein the belt is pervious to enable air to pass through and provide secondary air cushions for supporting conveyed articles on the belt. Ackroyd purports to disclose that there is wall boundary means for containing the secondary air cushions, and that the air supply to the conveyor belt is by way of load responsive valves which open in the presence of a conveyed article. Ackroyd purports to disclose that dual air pressures enable articles to be hovered and manouvered above the belt whilst the conveyor is in operation.

SUMMARY

The following summary is intended to introduce the reader to various aspects of the applicant's teaching, but not to define any invention.

According to some aspects, there is provided a conveyor system mounted to a trailer, comprising: a frame; a conveyor mounted to the frame and having a carrying surface and an opposite rear surface, the conveyor operable to move the carrying surface between a first end of the trailer and a second end of the trailer while the rear surface passes over a support surface of the frame; a pressurized air system, including: an air supply portion configured to be coupled to a truck-based air supply of a truck to receive pressurized air from the truck-based air supply, and an air delivery portion fluidly joined to the air supply portion to receive the pressurized air from the truck-based air supply, the air delivery portion operable to direct the pressurized air at the rear surface of the conveyor to reduce friction between the support surface of the frame and the rear surface of the conveyor.

In some examples, the conveyor system includes a controller operable to sense a movement initiation force needed to initiate movement of the conveyor, and the controller is operable to turn on the air delivery portion to deliver pressurized air at the rear surface of the conveyor if the movement initiation force is greater than a threshold initiation force.

In some examples, the controller is operable to sense a movement maintaining force needed to maintain movement of the conveyor when the conveyor is moving, and the controller is operable to turn off the air delivery portion to cease delivering pressurized air at the rear surface of the conveyor if the movement maintaining force is less than a threshold maintaining force.

In some examples, the controller is operable to initiate movement of the carrying surface between the first end and the second end of the trailer while the air delivery portion is delivering pressurized air at the rear surface of the conveyor.

In some examples, the conveyor is an endless conveyor.

In some examples, the endless conveyor is an endless conveyor belt.

In some examples, the air delivery portion includes a plurality of air jet nozzles, the plurality of air jet nozzles spaced apart from one another.

In some examples, the truck-based air supply is an air compressor.

In some examples, the truck includes a brake system including a storage container and the air compressor.

In some examples, the air compressor is coupled to the storage container to supply the pressurized air to the storage container, and the air supply portion is configured to be coupled to the storage container to receive the pressurized air from the storage container.

In some examples, the trailer does not include an air compressor.

According to some aspects, there is provided a method of operating a conveyor system of a live-bottom trailer, comprising: joining a pressurized air system of the conveyor system to a truck-based air supply of a truck to receive pressurized air from the truck-based air supply; directing the pressurized air against an underside of a conveyor of the conveyor system, the underside being opposite a carrying surface; and moving the carrying surface between a first end of the trailer and a second end of the trailer while directing the pressurized air against the underside of the conveyor.

In some examples, the method further comprises sensing that a movement initiation force needed to initiate movement of the carrying surface is greater than a threshold initiation force, and directing the pressurized air against the underside of the conveyor in response to sensing that the movement initiation force is greater than the threshold initiation force.

In some examples, the method further comprises sensing that a movement maintaining force needed to maintain movement of the carrying surface when the carrying surface is moving is less than a threshold maintaining force, and ceasing, in response to sensing that the movement maintaining force is less than the threshold maintaining force, to direct the pressurized air against the underside of the conveyor while continuing to move the carrying surface between the first end of the trailer and the second end of the trailer.

In some examples, the truck-based air supply is a brake system of the truck, the brake system including a compressed air storage container, and joining the pressurized air system to the truck-based air supply includes joining the pressurized air system to the compressed air storage container to receive the pressured air from the compressed air storage container.

According to some aspects, there is provided a live-bottom trailer having a conveyor system, the conveyor system comprising: a frame; a conveyor mounted to the frame and having a carrying surface and an opposite rear surface, the conveyor operable to move the carrying surface between a first end of the live-bottom trailer and a second end of the live-bottom trailer while the rear surface passes over a support surface of the frame; and a pressurized air system operable to direct pressurized air at the rear surface of the conveyor to reduce friction between the support surface of the frame and the rear surface of the conveyor.

In some examples, the pressurized air system includes: an air supply portion configured to be coupled to a truck-based air supply of a truck to receive the pressurized air from the truck-based air supply, and an air delivery portion fluidly joined to the air supply portion to receive the pressurized air from the truck-based air supply, the air delivery portion operable to direct the pressurized air at the rear surface of the conveyor to reduce friction between the support surface of the frame and the rear surface of the conveyor.

In some examples, the conveyor system includes a controller, the controller operable to: sense a movement initiation force needed to initiate movement of the conveyor; turn on the air delivery portion to deliver pressurized air at the rear surface of the conveyor if the movement initiation force is greater than a threshold initiation force; sense a movement maintaining force needed to maintain movement of the conveyor when the conveyor is moving; turn off the air delivery portion to cease delivering pressurized air at the rear surface of the conveyor if the movement maintaining force is less than a threshold maintaining force; and initiate movement of the carrying surface between the first end and the second end of the trailer while the air delivery portion is delivering pressurized air at the rear surface of the conveyor.

DETAILED DESCRIPTION

Although method steps may be described (in the disclosure and/or in the claims) in a sequential order, such methods may be configured to work in alternate orders. In other words, any sequence or order of steps that may be described does not necessarily indicate a requirement that the steps be performed in that order. The steps of methods described herein may be performed in any order that is practical. Further, some steps may be performed simultaneously.

Referring toFIG.1, illustrated is a trailer100(e.g., a semi-trailer). The trailer100includes a longitudinal axis102extending between a first or front end104and a second or rear end106. Trailer100includes a vertical axis108extending between a top or upper end110and a bottom or lower end112, the vertical axis108is perpendicular to the longitudinal axis102. Trailer100also includes a lateral axis114that is perpendicular to each of the longitudinal axis102and the vertical axis108.

In some examples, trailer100includes a frame or chassis116extending from the front end104to the rear end106with a hitching system118at the front end104. In some examples, rear end106of the trailer100may be openable (e.g., the rear end106may include an openable gate or door). The trailer100may include a wheel or drive system120at the lower end112. In some examples, the trailer100is open at the top end110(e.g., closed by a tarp or other removeable and flexible cover122).

Referring now toFIGS.2and3, in some examples the trailer100includes a conveyor system130. For example, the trailer100may be a live bottom trailer100with a conveyor system130to, e.g., carry granular material to the rear end106of the trailer100.

The conveyor system130includes a frame132(e.g., with conveyor frame132mounted to trailer frame116) and a conveyor136mounted to the frame132. The conveyor includes a carrying surface140and an opposite rear or back surface142.

In some examples, the conveyor system130(e.g., an endless conveyor belt, a moving floor, and/or a moving end wall) is operable to move the carrying surface140between the first end104and the second end106, while the rear surface142passes over a support surface146of the frame116(e.g., the rear surface142passes directly over the support surface146or within 10 cm, 5 cm, or 1 cm thereof). The support surface146may be an upper surface of a support plate, and may be, e.g., a planar surface and/or horizontally extending). The support surface may be provided to, e.g., support the conveyor136when a load is resting and/or dropped on the conveyor136(e.g., the conveyor136may press down against the support surface to spread the force of the weight and/or momentum of the load).

The conveyor136may be an endless conveyor136, such as a conveyor belt136(e.g., an endless conveyor belt extending between pulleys148). The belt136may be a flexible material. In some examples, the conveyor136is a light weight conveyor. For example, the conveyor may be a reduced strength conveyor belt (e.g., less than 400, less than 350, or less than 300 strength per inch and/or at least 10% less than standard strength per inch, such as less than 387 strength per inch if the regular belt has a 430 strength per inch). For example, a regular belt may be a 430 strength per inch belt and the conveyor136may be a 320 strength per inch friction bareback belt, which may reduce the weight by, e.g., 300 lbs. A lighter weight conveyor may increase the amount of payload the trailer100is able to carry.

In some examples, the conveyor system130may include a reduced-size pulley148. For example, the conveyor system130may include a head pulley that is less than 20 inches, less than 18 inches or less than 16 inches and/or more than 10% smaller than a standard head pulley. For example, the conveyor system130may have a 14″ head pulley, which may reduce the weight of the conveyor system by, e.g., 500 lb.

Referring now toFIG.4, the conveyor136may include an upper run150above the support surface146and a lower or return run152beneath the support surface146. The carrying surface140may be an upper surface of the upper run150, and the rear or underside surface142may be a lower surface of the upper run150.

Referring now toFIGS.2to5, the conveyor system130includes a pressurized air system160. The pressurized air system160is operable to direct pressurized air at the rear surface142of the conveyor136. For example, the pressurized air system160may be operable to direct compressed air between the rear surface142and the support surface146to, e.g., reduce friction between the support surface146of the frame116and the rear surface142of the conveyor136. In some examples, the pressurized air system160includes an air supply portion162and an air delivery portion164.

The air supply portion162is configured to be coupled to a truck-based air supply of a truck168(i.e., a tractor unit) to receive pressurized air from the truck-based air supply170. For example, the air supply portion162may include a hose and a coupling to join the hose to the truck-based air supply. The truck-based air supply170may be, e.g., a brake system172of the truck168. For example, the brake system172may include an air compressor174, and the air supply portion162may be coupled to the air compressor174to receive compressed air. The air supply portion162may be joined to the air compressor174indirectly, such as via a storage tank176. The air compressor174may supply compressed air to the storage tank176and the air supply portion162may be coupled (e.g., directly) to the storage tank176to receive compressed air from the storage tank176. In some examples, the trailer100does not include an air compressor (e.g., to reduce the weight of the trailer100).

In some examples, the air supply portion162is only coupled directly to the storage tank176and can only use the air in the storage tank176(i.e., the air supply portion162may not be connected directly to the air compressor174to receive an unlimited supply of compressed air). For example, the conveyor system130may be limited to the use of the amount of air in the storage tank176, or a portion thereof as set by regulations governing how much compressed air reserve must be maintained in the tank176, and would need the storage tank176to be replenished (e.g., by operation of the truck168) before more air could be received. In some examples, the conveyor system130is configured to be limited to receiving a portion of the compressed air in the storage tank176(e.g., leaving at least 5, 10, 25, 50, 75, 80, 90, or 95 percent of the capacity of the tank capacity of the truck168that is available for use by the truck's systems, such as the brake system).

In some examples, the storage tank176may hold more than 50, more than 60 or about 80 liters of compressed air (e.g., at between 50 and 100 or about 75 PSI), and the conveyor system130may take at least 20, at least 30, at least 40 or about 50 liters of compressed air to unload a load from the trailer100. The conveyor system130may have a pressure protection system131to limit the amount of compressed air being taken from the truck168to ensure that truck brakes always have enough air.

The air delivery portion164is fluidly joined to the air supply portion162to receive the pressurized air therefrom. The air delivery portion164is operable to direct the pressurized air at the rear surface142of the conveyor136to, e.g., reduce friction between the support surface146of the frame116and the rear surface142of the conveyor136. For example, the air delivery portion164may include a nozzle180(e.g., fluidly joined to a manifold to which a hose of the air supply portion162supplies compressed air) that is selectively openable to direct air at the rear surface142of the conveyor136(e.g., at a central portion184of the conveyor136, such as within the central 50 percent of the width or the central 30 percent of the width, rather than adjacent a lateral edge). In some examples, the conveyor system130includes a plurality of nozzles180arranged in a spaced-apart arrangement along the length of the support surface146(e.g., two or more nozzles180evenly spaced along the length144). In some examples, directing the compressed air against the belt136forms raised pocket structures138between the belt and the support surface (e.g., the pockets138may form a lifted underside that is at least 1 mm, 10 mm, or 100 mm further from the support surface146than the surrounding underside142of the conveyor136).

In some examples, the conveyor system130also includes a controller188. The controller188is operable to sense a movement initiation force needed to initiate movement of the conveyor136(e.g., to begin movement from a dead stop), such as 300, 400, or 500 PSI measured from a hydraulic motor which drives the belt (e.g., if the force needed is about 500 PSI or greater the compressed air is used). For example, the conveyor136may be driven by a drive system190(e.g., a driven end pulley148), and the controller188may receive an input from the drive system190indicative of the force needed to initiate movement of the conveyor136.

The controller188is operable to turn on the air delivery portion164to deliver pressurized air at the rear surface142of the conveyor if the movement initiation force is greater than a threshold initiation force. This may reduce friction between the conveyor136and the support surface146(i.e., by providing a lifting force against the conveyor136), which may reduce the force needed to move the conveyor136and/or reduce the strain on the conveyor136(i.e., to prevent the conveyor136from breaking). The controller188may be operable to initiate movement of the carrying surface140between the first end104and the second end106of the trailer100(e.g., such that the carrying surface140moves part or all of the way from the first end to the second end or vice versa) while the air delivery portion164is delivering pressurized air at the rear surface142of the conveyor136.

In some examples, air is shut off once the conveyor136is moving (e.g., the controller188may receive an output from the drive system190indicating that the conveyor136is moving). This may reduce the amount of air used, which may keep the system from needing more compressed air than is available, since the amount of air available may be limited to all or a portion of the air stored in the storage tank176. Additionally or alternatively, the controller188may be operable to sense a movement maintaining force needed to maintain movement of the conveyor136when the conveyor136is moving (e.g., the controller188may receive an output from the drive system190when the conveyor136is moving indicating the force needed to keep it moving) and may be operable to turn off the air delivery portion164to cease delivering pressurized air at the rear surface142of the conveyor136if the movement maintaining force is less than a threshold maintaining force (which may be, e.g., as soon as the conveyor136is moving or after a portion of a load is no longer on the conveyor136).

Referring now toFIG.6, illustrated is a method200of operating the conveyor system130(e.g., the conveyor system130of a live-bottom trailer). The method200includes, at step202, joining the pressurized air system160of the conveyor system130to the truck-based air supply170of the truck168to receive pressurized air from the truck-based air supply170. For example, an operator may run a hose of the pressurized air system160from the trailer100to the truck168, and join the hose to the storage container176of the truck168(e.g., the storage container of the brake system of the truck168) via a coupling on a distal end of the hose.

Method200also includes, at step206, directing the pressurized air against the underside142of the conveyor136of the conveyor system130. For example, the operator may actuate a controller to open valves of the pressurized air system160to release the compressed air, and the pressurized air system160may direct the air against the underside142of the upper run150of the conveyor136(e.g., via nozzles180).

In some examples, pressurized air may be used whenever the conveyer system130is activated (e.g., compressed air may be used in all cases when starting the conveyor136movement and/or when running the conveyor136). However, in some examples, the method200includes, at step204, sensing that a movement initiation force needed to initiate movement of the carrying surface140is greater than a threshold initiation force, and proceeding with step206in response. Using compressed air only when the force needed to move the conveyor136is above a threshold may allow for a reduced use of air compared to using pressurized air continually and/or in response to non-sensed conditions.

Method200also includes, at step208, moving the carrying surface140between the first end104of the trailer100and the second end106of the trailer100while directing the pressurized air against the underside142of the conveyor136(i.e., to reduce the force needed to move the carrying surface). For example, the controller may turn on the drive system190of the conveyor system130to begin the motion of the conveyor136(e.g., with the upper run150moving towards the front end104or with the upper run150moving towards the rear end106), and the drive system190and the pressurized air system160may operate at the same time. This may allow for a lighter conveyor136(e.g., a thinner belt, a belt made of weaker material, and/or a belt without a chain loop) to be used (e.g., used without breaking or excessive wear) compared to running (e.g., operating and/or initiating) the drive system190without running the pressurized air system160.

In some examples, the method200includes stopping the pressurized air once the carrying surface140is moving (e.g., in response to sensing that the carrying surface140is moving and/or within 30, 10, 5, or 1 seconds of the beginning of motion of the carrying surface140relative to the support surface146). Alternatively, the method200may include, at step210sensing that the movement maintaining force needed to maintain movement of the carrying surface140when the carrying surface140is moving is less than a threshold maintaining force. The method200may also include, at step212and in response to step210, ceasing to direct the pressurized air against the underside142of the conveyor136while continuing to move the carrying surface140between the first end104of the trailer100and the second end106of the trailer100. For example, the method200may include directing pressurized air at the underside while starting (e.g., within 10, 5, or 1 second of starting) the movement of the conveyor, and then shutting off the pressurized air once the conveyor is moving (e.g., at a pre-determined speed).

The present invention has been described here by way of example only. Various modification and variations may be made to these exemplary embodiments without departing from the scope of the invention, which is limited only by the appended claims.