Abstract: A single-circuit refrigerator includes a refrigerant circuit in which the following are connected in series one after another between a pressure port and an intake port of a compressor: a condenser, a first throttle section, a first evaporator for cooling a first temperature zone of the single-circuit refrigerator, a second throttle section, a second evaporator for cooling a second temperature zone of the single circuit refrigerator, and an intake line. A downstream section of the intake line is connected with the first throttle section to form a first heat exchanger, and an upstream section of the intake line is connected with the second throttle section to form a second heat exchanger.

Abstract: The present invention is provided with an extraction device (40) including: a cooling unit for cooling gas that has been extracted from a condenser (5) and condensing condensed gas; and an exhaust pump (48) for discharging, to the exterior, uncondensed gas that has been isolated without having been condensed by the cooling unit. A current temperature difference, which is the difference between the current saturation temperature in the condenser (5) and the current outlet temperature of a cooling water heat transfer tube (5a), and a planned temperature difference, which is a planned value, are computed. Using information on an in-tube fouling temperature difference elevation, which is a difference between the saturation temperature in the condenser (5) and the outlet temperature of the cooling water heat transfer tube (5a) and which is predetermined assuming in-tube fouling of the cooling water heat transfer tube (5a), the temperature difference elevation due to the current in-tube fouling is computed.

Abstract: A system for monitoring and reporting internal refrigeration unit temperatures includes a temperature measuring device for placement within the refrigeration unit. The temperature measuring device has a first temperature sensors situated in a buffer solution for measuring an average temperature within the refrigeration unit and/or has a second temperature sensors exposed to ambient air within the refrigeration unit for measuring an instantaneous temperature within the refrigeration unit. A circuit periodically transmits the average temperature and/or the instantaneous temperature from the temperature measuring device to a server where the average temperature and the instantaneous temperature are analyzed to determine and/or predict a fault with the refrigeration unit. Upon determination and/or prediction of the fault, an alert is sent to at least one staff member indicating the refrigeration unit and fault.

Abstract: An HVAC system includes an indoor unit having a return air duct and a supply air duct in an enclosed space. The HVAC system includes an outdoor unit having a variable-speed condenser fan. A first temperature sensor is disposed in at least one of the return air duct, the supply air duct, or an enclosed space. A controller is operatively coupled to the first temperature sensor, and the variable-speed condenser fan. The controller is configured to determine whether at least one of over-cooling or over-heating of air in the enclosed space is occurring. Responsive to a determination that at least one of over-cooling or over-heating of air in the enclosed space is occurring, the controller adjusts a speed of the variable-speed condenser fan.

Abstract: Provided is a cold storage unit that has a high cold storage capacity, does not generate carbon dioxide, and enables recycling of the cold source. Also provided are a moving body and an ice slurry supply system. In the cold storage unit, a casing that defines a cold storage space has a heat insulating structure, a partition wall that faces the casing is provided at least at a top portion of the cold storage space, and a gap between the casing and the partition wall is filled with an ice slurry that is a mixture of brine and flake ice acquired by freezing the brine. In addition, it is possible to provide a supply port for supplying the ice slurry into the gap and a discharge port for discharging the ice slurry from the nap.

Abstract: The invention relates to a water pre-cooling jacket for a vertical multitubular-type ice-making machine comprising an ice maker (1) having an outer wall or jacket or sleeve in whose interior a series of vertical tubes (2) are disposed, containing water for freezing thereof, said ice maker having a cooling gas inlet (4) and an outlet (3) of said cooling gas, the pre-cooling jacket (5) having a channel (8) for recovering the cold from the cooling gas having an inlet (6) on the lower part of the pre-cooling jacket (5) and an outlet (7) on the upper part of this jacket (5), said duct extending spirally, or with any other geometry and achieving a reduction in temperature from 21° C. at the inlet to 7° C. at the outlet.

Abstract: A refrigerator includes: a cabinet in which a refrigerating compartment is provided; a first door connected to the cabinet to open and close the refrigerating compartment and having an opening; a housing provided in the first door and accessible through the opening therein; an ice making room provided in the housing; a storage room that is provided below the ice making room and maintained at a temperature different from that of the refrigerating compartment; a guide duct provided below the ice making room to guide discharge of ice; a second door connected to the first door; a dispenser disposed on a front surface of the second door; and a discharge duct provided in the second door, wherein, when the second door is closed, the guide duct communicates with the discharge duct, and ice made in the ice making room is discharged to the dispenser.

Abstract: The present disclosure relates to a heat exchanger for refrigerator and a refrigerator having the same. The heat exchanger for refrigerator includes a plurality of heat transfer continuously arranged in multiple stages from a windward side to a leeward side, wherein the heat transfer fins disposed in the lower stage are offset in one of the column direction and the width direction from the plane's perspective.

Abstract: The present invention provides a refrigerator comprising: a cabinet provided with a storage chamber; an inner case that forms the exterior of the storage chamber; a first door rotatably installed on the cabinet so as to open/close one side of the storage chamber; a second door having a pillar that rotates such that the same can contact the first door, the second door being rotatably installed on the cabinet so as to open/close the other side of the storage chamber; and a transfer member provided inside the inner case so as to sense rotation of the second door and to guide rotation of the pillar, wherein the transfer member comprises an up/down movement guide portion that moves downward, when the pillar approaches, and contacts the pillar while the pillar remains unfolded.

Abstract: Disclosed are a refrigerator and a refrigerator door opening apparatus. The refrigerator includes a cabinet forming a storage space; a door configured to open and close the storage space; a panel installed on a front surface of the door to form an external appearance; a door handle provided in the panel and operable to open the door; and a door opening apparatus coupled to the door handle and configured to assist in opening the door. The door opening apparatus includes a main module installed inside the panel and configured to protrude backward from the panel according to the operation of the door handle; and a sub-module provided at an end portion of the door corresponding to the main module and configured to protrude backward in conjunction with the main module to push the cabinet and open the door.

Abstract: The present invention provides a refrigerator comprising a cabinet having a storage chamber; an inner case forming the exterior of the storage chamber; a first door pivotally provided to the cabinet and opening and closing one side of the storage chamber; a second door having a pillar rotated so as to come into contact with the first door, pivotally provided to the cabinet, and opening and closing the other side of the storage chamber; and a driving member provided at a lower end of the second door so as to move together with the second door, and operating the pillar so as to fold or unfold the pillar, wherein the pillar has a first catching protrusion and a second catching protrusion, which are selectively caught by the driving member.

Abstract: The present invention provides a refrigerator comprising: a cabinet having a storage chamber; an inner case that forms the exterior of the storage chamber; a first door rotatably installed on the cabinet so as to expose/cover one side of the storage chamber; a second door having a pillar that rotates such that the same can contact the first door, the second door being rotatably installed on the cabinet so as to expose/cover the other side of the storage chamber; and a transfer member provided on the inner case so as to sense the rotation of the first door and to guide the rotation of the pillar.

Abstract: There is disclosed a refrigerator including an inner case that defines an exterior appearance of a storage space, with a communication hole formed therein, an outer case spaced apart a predetermined distance from the inner case, with a communication formed at a position corresponding to the communication hole of the inner case, a vacuum space provided between the inner case and the outer case, with being maintained vacuum, to insulate the inner case from the outer case, and a connection pipe passing through the vacuum space, to connect the communication hole of the inner case and the communication hole of the outer case with each other.

Abstract: The present invention discloses a refrigerator and a humidity control method for the same. The refrigerator comprises a humidity controlling device to controllably maintain moisture and/or perform humidification. The humidity controlling device is configured to: set a target humidity value, measure an actual relative humidity value of a target space, and calculate a target water replenishing mass W based on a difference between the two values and a current temperature of the target space; measure and calculate a water replenishing time T, and adjust the humidity controlling device so as to maintain its maximum humidifying rate Vmax within the time T to achieve the humidification purpose; and adjust the humidity controlling device so as to maintain a humidifying rate consistent with a water vapor loss rate in the target space to achieve the moisture maintaining purpose.

Abstract: A beverage cooling apparatus for imparting coldness to beverage containers includes a base having a planar configuration and having a pair of side walls extending upwardly from ends of the base. The apparatus includes a guide member that includes first and second end portions and defining a plurality of apertures spaced apart from one another between the first and second end portions thereof that are configured to selectively receive and suspend the plurality of beverage containers, respectively. The first and second end portions of the guide member are coupled to upper ends of the side walls of the cooling member, respectively. The cooling member includes a temperature transfer material that transfers hot or cold heat energy to beverage containers suspended in apertures, respectively, such that they touch or are in proximity to the cooling member. The cooling member is separable from the guide member and re-frozen for later use.

Abstract: A process for removing light components from an ethylene stream may include providing a dried ethylene stream containing ethylene, ethane, CO, CO2, H2, CH4, and C3+ hydrocarbons. The process may include sending the dried ethylene stream to a stripper to produce an overhead stream containing ethylene, CO, H2 and CH4, and a bottom stream containing ethylene, ethane, CO2, and C3+ hydrocarbons. The gaseous phase on top of the stripper may be condensed in a heat exchanger cooled by a refrigerant stream to get a first gaseous phase and a first liquid phase. The first gaseous phase may be condensed in a heat exchanger cooled by liquid ethane or liquid ethylene to get a second gaseous phase containing ethylene CO, H2 and CH4 and a second liquid phase. The first and second liquid phases may be the reflux of the stripper.

Abstract: A low-temperature drying apparatus includes a furnace body, an object holder, an infrared light transmitting plate, a supply device, a discharge device, and infrared heaters. The object holder holds an object to be dried so that the object to be dried is placed in the furnace body. The infrared light transmitting plate is arranged on a surface of the furnace body that faces the object holder. The cooling flow generating device generates a cooling flow in a space between the object to be dried that is held by the object holder and the infrared light transmitting plate. The infrared heater is disposed to face the infrared light transmitting plate in an open space outside the furnace body.

Abstract: A bale dryer including a support frame, at least one air intake manifold movably coupled to the support frame for supplying heated air, a bale retainer coupled to the support frame and configured for retaining at least one bale in a fixed position vertically spaced from the at least one air intake manifold, and an actuator coupled to the at least one air intake manifold and configured to move the at least one air intake manifold between a retracted positon and an extended positon.

Abstract: In some embodiments, a grain drying apparatus may include a drum with a grain auger including a flighting with air holes. The drum may be surrounded by an outer drum, the inner drum including a plurality of drum air holes. A volume of dehydrated air may pass around a helical air diverter, located in an annulus between the inner drum and the outer drum, and through the grain, thereby drying the grain.

Abstract: This application relates to a system and methods for the exsiccation of material objects. The system can include a ventilation device. The material object can be attached to the ventilation device. The system can further include a container for the ventilation device and material object. The system can be attached and detached to a vehicle without the need for tools and can be compatible with preexisting vehicle roof racks.

Abstract: A method to thermally convert alternative fuels within a loop seal reactor by utilizing preheated/calcined cement meal as the heat source within which alternative fuels are immersed, subjected to drying, pyrolysis and subsequently charred, and an apparatus utilized to practice such method.

Abstract: A kiln and method for firing basic ceramic articles; the kiln comprises a conveying device for conveying the basic ceramic articles along a given path through a firing chamber, in which the basic ceramic articles are heated, a cooling chamber, in which the basic ceramic articles are cooled so as to obtain ceramic products; and an extraction device adapted to generate two gas flows in the firing chamber; the gas flows come from two opposite ends of the firing chamber and meet in the extraction device.

Abstract: A drill bit for improving performance of a drilling machine is provided. The drill bit includes a drill bit body with a rear end adapted to be connected to a drilling machine, and a leading end with a flat face perpendicular to a longitudinal axis (X-X) of the drill bit body. The drill bit body includes a first tapered portion with diameters increasing from the flat face of the leading end to a maximum diameter (Dmax), a second tapered portion with diameters decreasing from the maximum diameter (Dmax) to the rear end of the drill body, at least three partly-circular recesses formed in the drill bit body thus delimitating as many tapered drilling faces, each of them extending from the flat face of the leading end to the maximum diameter (Dmax). The flat face and the tapered drilling faces have a plurality of protruding teeth and the teeth are cylindrical and have a longitudinal axis (Y-Y) forming an angle with the face supporting the teeth which is less than or equal to 90°.

Abstract: In a door structure of a heat treatment furnace performing a heat treatment of a workpiece, there are provided: a first opening member and a second opening member in which workpiece passing ports where the transferred workpiece passes are formed; and a sheet shutter, the sheet shutter is provided with a winding portion and a shutter portion, the shutter portion is disposed between the first opening member and the second opening member, the shutter portion is provided with a first sheet portion which covers the workpiece passing port of the first opening member and a second sheet portion which covers the workpiece passing port of the second opening member at a time that the shutter portion is closed, and it is configured that a gas storage portion is formed between the first opening member and the second opening member at the time that the shutter portion is closed.

Abstract: A duct system of an electric arc furnace includes a plurality of walls each including sinuously winding piping having an inlet and an outlet, and a portion of a first wall of the plurality of walls forming a working platform. The platform is movable between a raised position and a lowered position. In the raised position, the portion of the first wall is disposed in proximate vertical alignment with the remainder of the first wall. In the lowered position, the portion of the first wall is disposed substantially perpendicularly to the remainder of the first wall. The portion of the first wall is sized to occupy a cross-sectional area formed by the plurality of walls such that the portion of the first wall is disposed in close proximity to the other of the plurality of walls.

Abstract: The present invention is to resolve a problem such as the above, the purpose being providing a heat exchanger capable of improving heat exchange efficiency by allowing the amount of heating medium flowing through heat medium channels, which are in multiple layers between a plurality of plates, to be evenly distributed. The present invention comprises a heat exchange part having heating medium channels, through which heating medium flows, and combustion gas channels, through which combustion gas burned in a burner flows, adjacently disposed in alternation in the spaces between the plurality of plates, the heat exchange part being provided in multiple numbers in a stacked structure, and having a heating medium distribution part for narrowing the channel at points where the flow direction of the heating medium is switched in adjacently located heating medium channels.

Abstract: A heat exchanger assembly is provided. The heat exchanger assembly may comprise a hot layer disposed between at least two cold layers. The hot layer may comprise a hot layer fin disposed within a hot layer closure bar. The hot layer closure bar may comprise a parting sheet support coupled to a frame. The parting sheet support may be configured to support a parting sheet while also allowing a fluid flow through the hot layer. The parting sheet support may comprise fluid channels configured to allow the fluid flow through the parting sheet support.

Abstract: A plate heat exchanger, and a heat exchanger plate for the plate heat exchanger for heat exchange between a first fluid and a second fluid are disclosed. The heat exchanger plate comprises a heat exchanger area comprising a first end zone, a central main zone adjoining the first end zone, a second end zone adjoining the central main zone, and a corrugation of ridges and valleys on the heat exchanger area. A longitudinal center axis extends along and through the three zones. The ridges and valleys extend along a respective continuous line, which is at least partly curved and forms an angle of inclination with the longitudinal center axis. The angle of inclination at the longitudinal center axis is less steep for the continuous lines at the first end zone than at the central main zone.

Abstract: To provide a heat pipe where the heat pipe has an excellent capacity for absorbing a non-condensable gas such as a hydrogen gas thus exhibiting excellent heat transfer characteristics. The heat pipe includes: a container having a cavity portion inside the container; a wick structure disposed in the cavity portion; a working fluid sealed in the cavity portion; and a metal which absorbs hydrogen at 350° C. or below and releases no hydrogen at 350° C. or below, the metal being disposed in the cavity portion.

Abstract: A system and related method that provides, but is not limited thereto, a thin structure with unique combination of thermal management and stress supporting properties. An advantage associated with the system and method includes, but is not limited thereto, the concept providing a multifunctional design that it is able to spread, store, and dissipate intense thermal fluxes while also being able to carry very high structural loads. An aspect associated with an approach may include, but is not limited thereto, a large area system for isothermalizing a localized heating source that has many applications. For example it can be used to mitigate the thermal buckling of ship deck plates, landing pad structures, or any other structures subjected to localized heating and compressive forces.

Abstract: A stacked plate heat exchanger having a structure that can be temporarily fixed by a simple structure in brazing, without using additional expensive parts includes a top plate, a bottom plate and a plurality of inner plates, wherein an upwardly bent tab part is formed on at least one of the plates, a cutout part is formed in plates other than the plate on which the tab part is formed, and each plate is stacked and fixed to one another with the tab part and the cutout part in a fitted state.

Abstract: A heat exchanger and a method for additively manufacturing the heat exchanger are provided. The heat exchanger includes a housing defining a flow passageway having a plurality of heat exchange banks stacked therein. Each heat exchange bank includes a plurality of heat exchange tubes that form a lattice structure that extends from a first end proximate a central manifold outward along the radial direction toward a second end proximate an annular outer manifold. The central manifolds and the annular outer manifolds fluidly couple the heat exchange tubes of adjacent heat exchange banks in an alternating manner to form a serpentine flow path for a flow of heat exchange fluid.

Abstract: A header for a heat exchanger includes a first barrel and a second barrel stacked on top of each other and being separated by a septum which may include one or more apertures. The first barrel and the second barrel may define a first manifold and a second manifold, respectively, which may be in fluid communication via the apertures in the septum. An inlet manifold is in fluid communication with the first manifold and the second manifold for providing a flow of heated fluid, the heated fluid being distributed through the first manifold and the second manifold before passing through a plurality of heat exchange tubes that extend from each of the first manifold and the second manifold.

Abstract: A heat exchanger includes a heat exchanger core, a header defining a header manifold, and a transition portion that provides fluid communication between the heat exchanger core and the header manifold. The transition portion includes a transition tube extending between the header and the heat exchanger core, a header junction where the transition tube joins the header, and a splitting junction that splits the transition tube into the plurality of heat exchange tubes. The header junction may define elliptical inlet apertures, a large filleted joint, and a junction thickness that is greater than a header wall thickness.

Abstract: A heat exchanger for heating a fluid in an incineration plant, comprising at least one heat exchanger component wherein the side in contact with the flue gas has an oxide layer comprising an ?-Al2O3 which protects the heat exchanger component against corrosion caused by corrosive compounds entrained or comprised by the flue gas.

Abstract: In the present disclosure, a flow path member includes a substrate, a flow path and a first oxide layer. The substrate contains non-oxide ceramics, and includes an outer surface. The flow path is in the substrate, and includes an inlet and an outlet. The first oxide layer is disposed on the outer surface.

Abstract: An apparatus has a housing with at least one gutter, a body of fill material disposed in the housing, a liquid distribution system disposed in the housing and positioned above the fill material, a fan positioned below the body of fill material for blowing air upward through the fill material, a liquid collection assembly positioned between the fill material and the fan for collecting the liquid gravitating through the fill material. The liquid collection assembly has at least one troughless, open sided surface element angled so gravity is utilized to capture the down flowing liquid to provide a barrier between the fill media and the fan and to carry the liquid down the surface element and into the at least one gutter.

Abstract: A splash bar for use in a cooling tower includes bottom, top, first side and second side portions. The bottom portion has first and second edges and is configured to be supported by horizontal hanger support members of a splash bar hanger grid along a width between the first and second edges. The top portion has first and second edges and is arranged substantially parallel with the bottom portion. The first side portion extends from the first edge of the bottom portion to the first edge of the top portion and the second side portion extends from the second edge of the bottom portion to the second edge of the top portion. The first and second edges of the top portion are closer to one another than the first and second edges of the bottom portion. A plurality of openings are formed through each portions.

Abstract: According to one embodiment, a system includes a high side heat exchanger, a load, a compressor, and a horizontal oil separator. The high side heat exchanger is configured to remove heat from a refrigerant. The horizontal oil separator comprises a centrifugal chamber, an oil, a cut line, a filter, a collector, and an outlet. The centrifugal chamber is configured to receive the refrigerant from the compressor and rotate the refrigerant, wherein rotating the refrigerant separates an oil from the refrigerant. The cut line is configured to prevent the oil separated in the centrifugal chamber from combining with the refrigerant. The filter is configured to separate additional oil from the refrigerant. The collector is configured to collect the oil separated in the centrifugal chamber and the additional oil. The outlet is configured to discharge the refrigerant to the high side heat exchanger.

Abstract: A supply circuit for a heat exchange medium for a consumer having an inflow line for the heat exchange medium and a return line for the heat exchange medium, the lines being connected to one another by way of a consumer heat exchanger. A pumping device for conveying the heat exchange medium through the supply circuit is a frequency-controlled pumping device having a conveying pump and a frequency converter which is assigned to the conveying pump. For an industrial plant, a primary circuit is connected to a supply circuit of this type as a secondary circuit. In either case, the supply circuit is operated selectively in one of two operating modes. In a first operating mode, the temperature of the heat exchange medium which enters into the consumer heat exchanger from the inflow line is set by way of an admixture control operation in which the temperature of the heat exchange medium which enters into the consumer heat exchanger from the inflow line is set by way of an actuation of the valve.

Abstract: The present invention provides a pistol with a frame having a rear grip, a trigger facility forward of the grip and an upper surface. An elongated slide connects to the frame and is operable to reciprocate along the upper surface. The frame defines a trigger recess open above the trigger facility at the upper surface. An insert has a major portion removably received in the trigger recess and has a rail extending from the major portion above the upper surface. The frame rail is adapted to connect with the slide to constrain reciprocation of the slide.

Abstract: A receptacle for collecting casings ejected from a firearm applied with a magazine includes a housing having an upper opening, a lower opening, and an interior defined within the housing between and in communication with the upper and lower openings. The upper opening is opened and can be mounted to be spaced apart from the ejection port of a firearm. A gate in the lower opening pivots between open and closed positions; the lower opening is closed when the magazine is received in the firearm and is opened when the magazine is removed from the firearm.

Abstract: In an embodiment an electronic device comprising of a processing module, storage module comprising an application software program, memory module, display driver module, display module, detection module, power supply module; configured to be capable of detecting and displaying force events.

Abstract: A method of modifying a firearm barrel comprising the steps of milling an existing barrel to create a sloped area with a larger diameter at a chamber end and a small action moving toward the muzzle end; placing an barrel nut on the barrel; placing a chamber bushing having a step with the step disposed at the chamber end; placing a brass pressing guide on the barrel and placing the barrel assemble with brass press guide and rear jacket tube in a press to press fit these components together; placing a gas block on the barrel adjacent to the rear jacket tube pressing the components tougher using the press; placing a front jacket tube on the barrel adjacent to the gas block and pressing the components tougher using the press; covering the threads of the barrel and placing a pour guide on the barrel; filling a void defined between the front jacket tube, rear jacket tube and barrel with a filler; placing a centering device on the barrel so that it is operatively associated with the front jacket tube to center the b

Abstract: An auto-loading firearm having a system for switches between live fire and training modes via a selector switch mounted either on the firearm frame or on a specially designed training attachment. A multi-part transfer bar, between the trigger and sear, can be selectively connected in a live fire mode and spaced apart in a training mode. A selectively engageable trigger resetting mechanism automatically returns the trigger to its set position after firing the firearm is in training mode.

Abstract: A novel and improved rotating stock butt and rotating sighting device that applies to a shoulder-fired firearm where the firing mechanism and the sighting device are elevated above the stock butt when in a horizontal shooting position. This system comprises a cooperation between the rotating stock butt and the rotating sighting device that allows the firing mechanism and the barrel to be offset to either the right or to the left of the stock butt while the rotating sighting device and sight bead remains on the top center of the firearm. This allows the shooter to mount the gun with very little head movement.

Abstract: An archery bow having a vertically positioned handle and an elongated center block affixed to the handle in a perpendicular configuration is provided. A pair of limbs are affixed to the center block and having a pair of cams (or pulleys) are rotatably attached to the limbs. A bowstring is formed between the first and second cams. The handle, center block, limbs, and bowstring are configured to discharge an arrow from a plane substantially perpendicular to a shooter. An arm stabilizer may also be provided to engage the forearm of the shooter and provide stabilization when the archery bow is aimed or fired.

Abstract: A retention structure of a crossbow contains a fixer including a seat, a rolling element, a resilient element, and a shock absorber. The seat has an affix sheet, a fitting tube, at least one threaded aperture, an accommodation aperture, and an engagement portion. A diameter of the engagement portion is less than that of the accommodation aperture. The seat contacts with the connection mount. At least one screwing element screws with the at least one threaded aperture via the at least one locking orifice. The rolling element is housed in the accommodation aperture of the seat and is limited by the engagement portion. The resilient element is housed in the accommodation aperture and abuts against the connection mount and the rolling element. The shock absorber has a through hole and fits on the fitting tube of the seat by using the through hole.

Abstract: A crossbow having an energizer is described herein. The crossbow, in an embodiment, includes a stock, a body coupled to the stock, and a plurality of limbs. Each of the limbs has a coupled limb end and an uncoupled limb end. The energizer, which includes an electrical power source, is operatively coupled to the limbs.

Abstract: Provided is a crossbow comprising a bow having a riser having a first side and a second side opposite the first side, a first limb set engaged to the first side, a second limb set engaged to the second side, a first cam set engaged to the first limb set, a second cam set engaged to the second limb set; an adjustable pulley set having at least a first pulley and a second pulley, wherein the pulley set is operationally engaged with and selectably movable with respect to the first cam, or the second cam, or the riser; a first power cord set extending from the first cam set and at least partially around the first pulley; and a second power cord set extending from the second cam set and at least partially around the second pulley.