65 results about "Spiral wound" patented technology

The invention relates to the technical field of heat exchangers, and discloses a control method and system for a spiral wound tube type heat exchanger based on the Internet of Things. The method comprises the following steps: acquiring flow velocity distribution data in a pipe in real time through a multi-point sensor to form a first data set, performing regional analysis to obtain a flow velocity deviation value, evaluating heat exchange abnormality, positioning an abnormal position, and generating an abnormal region distribution map; a dynamic parameter adjustment scheme is calculated in combination with a heat exchange efficiency target, a first adjustment instruction set is generated, a second flow rate data set is obtained after execution, and the matching degree is evaluated through a fuzzy control algorithm; if the preset standard is not met, a second adjusting instruction set is generated in combination with working condition requirements, and finally an operation state report is output. The method has the following effects that the flow velocity distribution in the spiral wound tube type heat exchanger is accurately controlled, the problems of local overheating and uneven heat exchange are effectively solved, the heat exchange efficiency is improved, the purpose of balancing energy consumption is achieved, and stable operation of the system is guaranteed.

An automatic graphite conveying device includes a mounting frame, a conveyor wheel, a first clamping wheel and a guide assembly, a gap is formed between the first clamping wheel and the guide assembly to convey a graphite strip, the mounting frame is configured with a mounting hole in a vertical direction for the graphite strip to pass through, the guide assembly includes a guide column and a second driver, the guide column is slidably mounted on the mounting frame, a guide plate is provided at an end of the guide column away from the mounting frame to guide the graphite strip to a winding machine for a spiral wound gasket, the mounting frame is slidably provided with a cutter, and a guide element with a guide hole is fixed on the mounting frame, and a cross-sectional area of the guide hole gradually decreases towards the mounting frame.

This utility model provides a pressure-resistant and flame-retardant PE hollow-wall spiral wound pipe, belonging to the technical field of hollow-wall spiral wound pipes. The pressure-resistant and flame-retardant PE hollow-wall spiral wound pipe provided by this utility model features a reinforcing tube with reinforcing ribs spirally wound on its outer circumference. Pressure-resistant filler is filled into the reinforcing ribs, improving the overall rigidity and pressure resistance of the spiral wound pipe, making it less prone to deformation and damage under external pressure. Simultaneously, a plastic spring is provided between the reinforcing tube and the spiral wound pipe body, providing internal support to the reinforcing tube and enhancing its ring stiffness and axial stiffness. Due to the plastic spring and the spirally wound reinforcing ribs on the outer circumference of the reinforcing tube, stress concentration is reduced, resulting in excellent bending resistance and preventing breakage of the spiral wound pipe. Furthermore, a flame-retardant and heat-insulating layer and a corrosion-resistant layer are provided on the outer circumference of the reinforcing tube, improving the flame retardancy and corrosion resistance of the spiral wound pipe.

This utility model relates to the field of spiral wound tube technology, specifically a multi-layer composite spiral wound tube structure, including a tube body with a supporting mechanism. The supporting mechanism includes an inner annular component fixedly connected to the outer wall of the tube body. Several inner annular components are arranged in an array. An outer protective tube is fixedly connected to the side of the inner annular component away from the tube body. Several arc-shaped tubes are arranged in an array on the outer wall of the outer protective tube. An outer annular groove is provided between the arc-shaped tubes and the outer protective tube. The cavity formed by the inner annular component, the outer protective tube, and the tube body is provided with an inner annular groove. A through groove is formed on the inner annular component. This utility model, through the reinforcing rib structure formed by the inner annular component and the outer protective tube, and the arc-shaped tubes dispersing external pressure, achieves a point-line-surface mechanical linkage, effectively improving the overall stability and deformation resistance of the tube body, enhancing its load-bearing capacity, and extending its service life.

A mixing machine used in hollow structure wall spiral winding pipe production equipment comprises a supporting frame, a mixing barrel installed on the supporting frame, a stirring shaft rotationally installed in the mixing barrel and a driving mechanism installed on one side of the supporting frame, the mixing barrel is transversely arranged to form a U-shaped groove structure with a top opening, materials can be poured into the mixing barrel from the top opening, and the mixing barrel is arranged in the U-shaped groove structure. The stirring shaft is transversely arranged in the material mixing barrel, the stirring shaft is driven by the driving mechanism to rotate, the multiple stirring rods extending in the radial direction are arranged on the stirring shaft, the stirring plates are arranged at the extending tail ends of the stirring rods, and materials in the material mixing barrel can be fully stirred through the transversely-arranged material mixing barrel and the multiple stirring rods; and when the stirring shaft rotates, the distance between the stirring plate and the bottom surface of the material mixing barrel does not exceed 3cm, so that even if the material is layered at the bottom, the stirring plate can stir the material, and the condition that the material is stacked at the bottom and cannot be stirred is avoided.

A crossbow includes a frame, first and second limbs, first and second cams, a drawstring, and first and second power cables. The frame includes a first side and a second side. The frame defines a projectile axis. The first limb is coupled to the first side and the second limb coupled to the second side. The first cam is coupled to the first side and configured to rotate about a first cam axis that is substantially parallel to the projectile axis. The second cam is coupled to the second side and configured to rotate about a second cam axis that is substantially parallel to the projectile axis. The drawstring is engaged with the first cam and the second cam. The first power cable is engaged with the first cam and the first limb. The second power cable engaged with the second cam and the second limb.

The utility model belongs to the technical field of machining, particularly relates to a ring bending device for a metal spiral wound gasket circular ring, and aims to solve the problems that manual size measurement is troublesome and welding is uneven in the background technology, the ring bending device comprises a bottom frame, a top frame is welded to the outer wall of the top of the bottom frame, and a side plate is welded to the outer wall of the top of the top frame. And the outer wall of one side of the side plate is fixedly connected with a guide rod. According to the utility model, along with continuous winding of the soft material, the size of the whole circular ring is continuously increased to contact with the pulley, the pulley is controlled to be close to the side plate, and the outer diameter of the circular ring can be accurately grasped by monitoring the distance of the calibration plate in real time through the photoelectric sensor, so that the size of the circular ring is quickly and effectively ensured to meet the standard; the laser welding head can uniformly weld the end part of the soft material along with downward pushing of the laser welding head by the cylinder and under the cooperation that the electric rotating chuck drives the circular ring to rotate, so that the position of a welding spot can be accurately grasped, and the welding uniformity is ensured.

The utility model relates to the technical field of winding pipes, in particular to an HDPE (high-density polyethylene) reinforced hollow winding pipe which comprises an outer layer and an inner layer, the inner wall of the outer layer is adhered to a high-strength adhesive, the inner wall of the high-strength adhesive is fixedly connected with a high-strength laminated steel wire mesh, and the outer wall of the high-strength laminated steel wire mesh is attached to the inner layer. The lower portion of the high-strength adhesive is fixedly connected with the inner layer, and a reinforcing mechanism is machined on the outer wall of the outer layer. Under the condition that the thicknesses of the outer layer and the inner layer are not changed, cavities in the spiral strips are extruded, deformed and rebounded, iron reinforcing wires in the fixing strips buffer impact force, direct contact between external force and the outer layer is reduced, and a high-strength laminated steel wire mesh is additionally arranged in a high-strength adhesive; the pulling force of the high-strength laminated steel wire mesh on the outer layer and the inner layer is enhanced, the situation that the outer layer and the inner layer are torn and damaged is reduced, and the overall using strength and the using environment are improved.

The pin type winding mechanism comprises a winding wheel and a top wheel which are oppositely arranged, the winding wheel can actively rotate, and a metal belt is wound on the winding wheel to form the winding gasket; a contact pin is arranged on the wheel face of the winding wheel, a connecting hole is formed in one end of the metal belt, and when the winding wheel rotates, the metal belt is rolled through insertion matching of the contact pin and the connecting hole. An inserting hole is formed in the wheel face of the winding wheel, and the inserting needle is telescopically arranged in the inserting hole. An elastic piece is arranged between the pin and the jack; under the elastic effect of the elastic piece, the pin tends to extend out of the jack. And when the contact pin retracts into the jack, the elastic piece is compressed. An adjusting sliding groove is formed in the side contour of the winding wheel and communicated with the inserting hole, and an adjusting pin is connected to one side of the inserting needle and correspondingly arranged in the adjusting sliding groove. According to the utility model, the connection mode of the metal belt and the winding wheel is improved, so that labor can be saved.

A cartridge filter includes a feedwater inlet, a first outlet and a second outlet, a tube arranged at the center of the cartridge filter, an interior volume of the tube being in fluid communication with the first outlet, and a spiral wound filter assembly extending radially outward from the central tube and including a prefilter, a reverse osmosis filter, and a postfilter. The prefilter is located radially outward from the reverse osmosis filter and the postfilter.

The utility model relates to the technical field of pipeline repairing, in particular to a pipeline cleaning device for repairing a pipeline through a trenchless spiral winding method. The device comprises a cleaning mechanism, pushing discs, a supporting advancing mechanism and a water inlet pipe which are sequentially arranged from front to back, the supporting advancing mechanism is used for being supported on the inner wall of a pipeline and driving the water inlet pipe to advance, and the pushing discs are arranged at the front end of the supporting advancing mechanism at intervals through connecting structures and used for pushing impurities on the inner wall of the pipeline to move forwards. The cleaning mechanism comprises a water spraying pipe and a cleaning brush which are arranged at the front end of the pushing disc, the water spraying pipe communicates with the water inlet pipe and is used for spraying water to the inner wall of the pipeline, and the periphery of the cleaning brush is used for being attached to the inner wall of the pipeline to brush the inner wall of the pipeline. The supporting advancing mechanism is used for driving the water inlet pipe to advance in the length direction of the pipeline, the cleaning mechanism is used for improving the impurity cleaning effect, the pushing disc is used for pushing impurities to move forwards, impurity accumulation is avoided, the cleaning process is prevented from being hindered, and the pipeline cleaning quality is guaranteed.

This invention discloses a BWFRP braided spiral wound power conduit, relating to the field of power cable protection conduit technology. It aims to solve problems such as significant decrease in tensile strength of existing BWFRP power conduits in humid and hot environments, insufficient interlayer bonding strength in multi-layer structures, difficulty in balancing ring stiffness and wall thickness, high material cost, inconvenient construction, and insufficient long-term reliability. The conduit includes a pipe body with a three-layer composite structure: an inner resin-rich layer, an outer weather-resistant and anti-aging layer, and an intermediate reinforcing layer accounting for 80%-90% of the wall thickness. The intermediate reinforcing layer includes an axial braided layer and a circumferential spiral wound layer; the axial braided layer is a ±55° bidirectional braided glass fiber cloth layer. This invention, through a composite structure of braiding and multi-angle alternating winding, and an interlayer hot-melt transition layer, significantly improves the axial and circumferential mechanical properties of the conduit, enhances interlayer bonding strength, improves strength retention after humid and hot aging, and optimizes the matching relationship between wall thickness and stiffness, achieving a balance between high strength and lightweight.

The utility model discloses a convenient-to-install one-piece roll type separation membrane component, including shell, central tube and membrane roll, the both ends of shell are equipped with the end cover that closely connects into one piece, the end cover includes cover plate and ring, the cover plate is fixed inside the ring, the ring includes the first ring and the second ring that are arranged on both sides of the cover plate, the first ring is sleeved outside the shell, the second ring is sleeved outside the shell, and the membrane roll is sleeved outside the central tube. The cover plate is provided with a water producing port and a water inlet and outlet port, the cover plate is provided with a water inlet and outlet pipe head communicated with the water inlet and outlet port, the outlet end of the water inlet and outlet pipe head is arranged on the outer side wall of the second ring, the surface, close to the shell, of the cover plate is provided with a flow dividing channel, and the second ring is provided with a plurality of U-shaped clamping grooves; according to the utility model, the stability and the sealing performance of the whole structure are improved, the assembly steps are reduced, the production efficiency is improved, the cost is reduced, the installation is convenient, the interference problem of the water producing pipe and the water inlet and outlet pipe is avoided, the installation is more flexible, the installation convenience is improved, the loading capacity is improved, and the application range of the product is expanded.

The utility model belongs to the technical field of winding reinforced structure wall A-type pipes, and particularly relates to an MUHDPE winding reinforced structure wall A-type pipe which comprises pipe bodies, lantern rings are fixedly arranged on the outer sides of the two ends of the pipe bodies, and a first semicircular steel sleeve shell and a second semicircular steel sleeve shell are arranged at the butt joint positions of the adjacent pipe bodies in a vertically sleeved mode. The first semicircular steel sleeve shell and the second semicircular steel sleeve shell are welded. The first semicircular steel sleeve shell and the second semicircular steel sleeve shell are connected to the outer side of the butt joint end of the pipe body in a sleeving mode, the first semicircular steel sleeve shell and the second semicircular steel sleeve shell are high in strength, excellent in extrusion resistance and capable of comprehensively wrapping and reinforcing the end of the pipe body, the end of the pipe body is not prone to deformation, and the butt joint position of the pipe body is not prone to deformation. The two-layer sealing effect is provided through the water retaining ring and the lantern ring, water is difficult to leak to the outer sides of the first semicircular steel sleeve shell and the second semicircular steel sleeve shell through the water retaining ring and the lantern ring, and therefore the sealing effect of the pipe body butt joint position is greatly improved.

Stabilized surfactant-based membranes and methods of manufacture thereof. Membranes comprising a stabilized surfactant mesostructure on a porous support may be used for various separations, including reverse osmosis and forward osmosis. The membranes are stabilized after evaporation of solvents; in some embodiments no removal of the surfactant is required. The surfactant solution may or may not comprise a hydrophilic compound such as an acid or base. The surface of the porous support is preferably modified prior to formation of the stabilized surfactant mesostructure. The membrane is sufficiently stable to be utilized in commercial separations devices such as spiral wound modules. Also a stabilized surfactant mesostructure coating for a porous material and filters made therefrom. The coating can simultaneously improve both the permeability and the filtration characteristics of the porous material.

This invention relates to the field of spiral wound molding technology and discloses an HDPE pipe spiral wound structural wall pipe spiral wound molding equipment, including a base, a vertical plate mounted on the top of the base, a pulley on the top of the vertical plate, a mandrel splicing assembly on the top of the pulley, and a cooling and shaping assembly on the outer wall of the mandrel splicing assembly. By employing high-frequency mechanical vibration of piezoelectric ceramic water spray, and transmitting the vibration to the cooling water interface, the surface tension of water molecules is broken, allowing atmospheric pressure cooling water to be directly atomized into uniform micro-droplets without the need for a high-pressure pump. The atomized droplets can be aligned with the adsorption holes and directionally sprayed onto the pipe surface to achieve efficient heat exchange, reducing energy consumption and making the droplet distribution more uniform. Utilizing the existing shaped adsorption holes as the spray channel for subsequent atomization cooling, vacuum adsorption + water-cooled spraying is achieved, simplifying the structure while ensuring cooling uniformity and eliminating cooling dead zones caused by nozzle arrangement deviations in traditional spray devices.

The invention provides a metal spiral wound gasket production device and process, and relates to the technical field of metal spiral wound gasket production, the metal spiral wound gasket production device comprises a placing frame and a core fixing mechanism arranged on the placing frame; a pushing air cylinder is fixedly connected to the containing frame, an abutting spring is fixedly connected to an output shaft of the pushing air cylinder, a sliding block is fixedly connected to the end, away from the abutting air cylinder, of the abutting spring, the sliding block is slidably connected with the containing frame, and an abutting rotating wheel is rotationally connected to the sliding block. And the abutting rotating wheel is used for abutting against the side wall of the positioning ring, an abutting block is slidably connected to the sliding block, an abutting wheel is rotatably connected to the abutting block, and the abutting wheel is used for abutting against the metal belt after winding. Looseness of the winding layer can be reduced, and installation of the outer ring can be assisted.

A pipe insulation is formed from multiple discrete sheets of fiberglass that are wetted with a binder composition. The sheets are spiral wound around a mandrel in a partially overlapping fashion. The wound sheets are further processed to interface with one another and form a unitary elongated cylinder. The binder in the elongated cylinder is then cured to form the pipe insulation.

This utility model discloses a winding device for producing metal spiral wound gaskets, including a bracket, two circular blocks passing through the middle of the bracket, a first support roller on one side of the bracket, the circular blocks being inserted into the first support roller, a second support roller detachably connected to one side of the bracket, and a third support roller on the other side of the bracket. A drive motor fixedly connected to one end of the third support roller is fixedly connected to the bracket, and two first support shafts are fixedly connected to the front of the bracket. This utility model has the advantage of tension adjustment.

The utility model relates to the technical field of metal spiral wound gaskets, in particular to a metal spiral wound gasket structure which comprises a stainless steel inner ring, a compression-resistant mechanism is arranged on the outer side of the stainless steel inner ring, the compression-resistant mechanism comprises connecting grooves formed in the upper side and the lower side of the stainless steel inner ring, and clamping inner rings are clamped in the connecting grooves. A special-shaped outer ring is fixedly connected to the side, away from the stainless steel inner ring, of the clamping inner ring, two sets of supporting plates are arranged in the clamping inner ring, the side, away from the stainless steel inner ring, of the special-shaped outer ring is in a concave shape, and an extrusion block is fixedly connected to the inner side wall of the special-shaped outer ring. According to the utility model, the stainless steel inner ring is matched with the compression-resistant mechanism, and the flexible graphite ring on the outer side of the V-shaped inner stainless steel ring is utilized to increase the overall deformation adaptability, so that the shape of the stainless steel inner ring can be flexibly adjusted when the stainless steel inner ring is stressed or deformed; and the supporting elastic cotton on the two sides extrudes the supporting plate to upwards abut against the elastic gasket and the extension ring so as to improve the elasticity of the edge.

This invention discloses a solid-wall spiral wound tube extrusion production equipment, belonging to the technical field of spiral wound tube forming equipment. It includes an injection molding machine body with a forming assembly mounted on it; a drive assembly includes a first gear rotatably mounted on the forming assembly and a second gear meshing with the first gear, the second gear being driven by a second motor; a feeding assembly includes an electric cylinder and a guide tube slidably connected to the first gear, a connecting plate mounted on the output end of the electric cylinder being rotatably connected to the guide tube, an electric gripper mounted on the guide tube, a driven roller rotatably mounted on one arm of the electric gripper, and a clamping rod fixedly mounted on the other arm. The driven roller of this invention, through its dual function of clamping and pressing, achieves seamless connection of molten material guidance, stable winding, and interface adhesion during the spiral wound tube production process; the top roller and the roller body work together to effectively prevent reverse slippage of the extruded material during winding, ensuring the continuity and stability of the winding process.

The invention relates to the technical field of storage racks, in particular to an FEP winding pipe which comprises a winding pipe body and further comprises a buffering assembly, the buffering assembly comprises an arch rubber frame and a buffering cylinder, the arch rubber frame is connected with the winding pipe body, and the buffering cylinder is connected with the arch rubber frame and the winding pipe body. When the winding pipe main body is subjected to pressure or impact force, the impact force can be transmitted to the circular-arch rubber frame, so that the circular-arch rubber frame is compressed and deformed to buffer the impact force, and meanwhile, in the compression deformation of the circular-arch rubber frame, a buffer cylinder between the circular-arch rubber frame and the winding pipe main body can be extruded; and through the stability of the circular arch structure of the circular arch rubber frame and the deformation buffering of the buffering cylinder, the cable in the winding pipe main body is subjected to anti-impact protection, and the cable is prevented from being damaged due to impact force.

This utility model discloses an anti-oxidation spiral wound pipe, comprising a spiral wound pipe body, with a protective strip spirally wound around the outer side of the spiral wound pipe body. Multiple vertical ribs are clamped onto the outer side of the protective strip. Each vertical rib has an open C-shaped structure, and the open structures of adjacent vertical ribs are arranged opposite each other. The protective strip, from the inside out, includes an adhesive layer, a buffer layer, a base layer, and an anti-oxidation layer. Through this structure, after the protective strip is wound around the outside of the spiral wound pipe, the vertical ribs are clamped onto the spiral wound pipe. The protective strip protects the spiral wound pipe and reduces contact with the external environment. The vertical ribs provide support, increasing the ring stiffness of the pipe, enabling it to better resist external pressure and maintain pipeline stability during underground installation. The overall protective effect of the protective strip improves the corrosion resistance and oxidation resistance of the spiral wound pipe.

A spiral wound membrane module, comprising a perforated core having an axially extending internal bore; at least one membrane packet comprising a folded membrane sheet defining a first outer face, a first inner face, a second outer face and a second inner face, the fold of the folded membrane sheet being a leading end of the membrane packet; a feed sheet positioned between the first and second inner faces so as to be sandwiched by the folded membrane sheet; a first permeate screen adjacent the first outer face of the membrane sheet defining a first permeate channel; a second permeate screen adjacent the second outer face of the membrane sheet defining a second permeate channel; and a fluid impermeable support coupled to the leading edge of the membrane packet. Also disclosed is a method of manufacturing the spiral wound membrane module.

The utility model discloses a pressure-resistant corrugated board, and relates to the technical field of corrugated paperboards, the pressure-resistant corrugated board comprises two outer-layer paperboards, and a spiral buffer mechanism and an arc-shaped buffer mechanism are sequentially arrayed between the two outer-layer paperboards; the spiral buffering mechanism comprises a left spiral which is fixedly connected with the surfaces of the two outer-layer paperboards in an abutting mode, and the surfaces of the two outer-layer paperboards are connected with a right spiral which is spirally wound with the left spiral in an abutting mode; the arc-shaped buffering mechanism comprises an arc-shaped plate which abuts against and is fixed to the surfaces of the two outer-layer paper boards, and a plurality of supporting rods used for supporting are fixed between the two sides of the surface of the arc-shaped plate and the upper-layer outer-layer paper board in a glued mode. In conclusion, the device has the advantages that the structural design is reasonable, the contact area between the pressure-resistant structure and the outer-layer paperboard is large, and various pressure-resistant structures are arranged, so that the pressure resistance of the corrugated paperboard is greatly improved.

The application discloses a fatigue life analysis method of a spiral wound heat exchanger based on tube bundle equivalence, and belongs to the technical field of life analysis of spiral wound heat exchangers. In order to solve the problems of high calculation cost and long simulation period of existing full tube bundle refined modeling, the application extracts target heat exchanger parameters to establish an analysis parameter set, uses a mixing law to equivalently convert a single hollow heat exchange tube into a solid tube, combines a Mori-Tanaka equivalent method to calculate macroscopic elastic constants of the wound tube bundle, and obtains an equivalent wound tube bundle model. After assembling the equivalent tube bundle model with the rest of the component models, finite element simulation is carried out, stress response of a dangerous point is extracted, Goodman correction formula is used to convert alternating dynamic load into a symmetric cyclic stress amplitude, and S-N curve is combined to obtain a permissible fatigue cycle number. The application is suitable for fatigue life evaluation of various spiral wound heat exchangers.

A coiled tube heat exchanger using a deformable support system and a method for manufacturing a tube bundle for the coiled tube heat exchanger. The coiled tube heat exchanger includes: a mandrel; a first pipe layer formed by winding one or more pipes around the mandrel; and a plurality of supports and spacers circumferentially arranged on an outer surface of the first pipe layer in an alternating pattern. A second tube layer is formed by winding one or more tubes around the mandrel, whereby the second tube layer contacts opposite sides of the support. A deformation force is applied to the second tube layer in a direction normal to the outer surface of each support, which causes the one or more tubes forming the second tube layer to deform the outer support surface of each support.

The invention relates to the technical field of gasket diameter measurement, in particular to a metal spiral wound gasket diameter measuring device which comprises a supporting seat, a moving platform capable of moving front and back and left and right is fixedly mounted on the upper surface of the supporting seat, and a light source base is fixedly connected to the upper surface of the moving platform. A lens measuring part is fixedly installed on the rear surface of the supporting seat through a supporting frame, a uniform laying mechanism for uniformly stacking gaskets is arranged above the moving platform, a displacement mechanism for adjusting the position of the uniform laying mechanism is fixedly installed on the left side face of the supporting seat, and a storage mechanism for temporarily storing excess materials is arranged on the left side of the uniform laying mechanism; through the arrangement of the uniform laying mechanism, when the diameter of the metal spiral wound gasket is measured, the gasket can be rapidly and uniformly laid, the efficiency of measuring the diameter of the gasket is improved, the measuring position of the measuring equipment is reasonably utilized, the placing amount of the gasket is larger during one-time measurement, and the efficiency is higher during batch measurement.

A crossbow includes a frame, first and second limbs, first and second cams, a drawstring, and first and second power cables. The frame includes a first side and a second side. The frame defines a projectile axis. The first limb is coupled to the first side and the second limb coupled to the second side. The first cam is coupled to the first side and configured to rotate about a first cam axis that is substantially parallel to the projectile axis. The second cam is coupled to the second side and configured to rotate about a second cam axis that is substantially parallel to the projectile axis. The drawstring is engaged with the first cam and the second cam. The first power cable is engaged with the first cam and the first limb. The second power cable engaged with the second cam and the second limb.