Aerobic exercise is a popular form of exercise that improves one's cardiovascular health by reducing blood pressure and providing other benefits to the human body. Aerobic exercise generally involves low intensity physical exertion over a long duration of time. Typically, the human body can adequately supply enough oxygen to meet the body's demands at the intensity levels involved with aerobic exercise. Popular forms of aerobic exercise include running, jogging, swimming, and cycling among others activities. In contrast, anaerobic exercise typically involves high intensity exercises over a short duration of time. Popular forms of anaerobic exercise include strength training and short distance running.
Many choose to perform aerobic exercises indoors, such as in a gym or their home. Often, a user will use an aerobic exercise machine to have an aerobic workout indoors. One type of aerobic exercise machine is a treadmill, which is a machine that has a running deck attached to a support frame. The running deck can support the weight of a person using the machine. The running deck incorporates a conveyor belt that is driven by a motor. A user can run or walk in place on the conveyor belt by running or walking at the conveyor belt's speed. The speed and other operations of the treadmill are generally controlled through a control module that is also attached to the support frame and within a convenient reach of the user. The control module can include a display, buttons for increasing or decreasing a speed of the conveyor belt, controls for adjusting a tilt angle of the running deck, or other controls. Other popular exercise machines that allow a user to perform aerobic exercises indoors include elliptical trainers, rowing machines, stepper machines, and stationary bikes to name a few.
One type of treadmill is disclosed in U.S. Pat. No. 5,772,560 issued to Scott R. Watterson, et al. In this reference, the treadmill has a tread base that is rotatably attached to and between a left upright and a right upright. The tread base is rotatable between a first position for performing exercises and an upright or storage position. A latching structure is provided to latch the tread base to the support structure. The treadmill also includes inclination structure for inclining the tread relative to the support surface when in the first position. The treadmill also includes rigid handles and in one configuration movable handles. The tread base also has a rigid undersurface or pan to fully enclose the underside of the tread base. A lift assist gas cylinder is also interconnected between the tread base and the feet attached to the uprights.
In one embodiment, a treadmill includes a deck, an incline mechanism attached to the deck, and a lift assist mechanism that offloads a portion of the lifting force from the incline mechanism when the incline mechanism changes an elevation of a portion of the deck.
The treadmill may further include a base frame and a rear portion of the deck pivotally attached to the base frame.
The incline mechanism further may include a first end attached to the deck and a second end attached to the base frame.
The lift assist mechanism may include a gas spring.
The gas spring further may include a first spring end attached to the deck and a second spring end attached to the base frame.
The deck may be declinable to a decline angle between zero degrees and negative 15 degrees.
The lift assist mechanism may include a first gas spring connected to the deck and connected to a base frame, and a second gas spring connected to the deck and connected to the base frame. The first gas spring and the second gas spring may be oriented in a scissor arrangement.
The treadmill may include an upright structure and the lift assist mechanism may include a first end connected to the deck and a second end connected to the upright structure.
The lift assist mechanism may include a gas spring.
The lift assist mechanism may include a cable and a cable length adjustment mechanism. The cable, in part, may support a weight of the portion of the deck when inclined.
The lift assist mechanism may include at least one coiled spring.
The deck may be selectively engagable with the lift assist mechanism.
The deck may be engagable with the lift assist mechanism when the deck is orientated in a range of engageable angles.
The range of engageable angles may include decline angles.
In one embodiment, a treadmill includes a deck, a base frame pivotally attached to the base frame, a lift motor attached to the deck and attached to the base frame, and a gas spring that offloads a portion of the lifting force from the lift motor when the lift motor changes an elevation of a portion of the deck.
The deck may be declinable to a decline angle between zero degrees and negative 15 degrees.
The deck may be selectively engagable with the lift assist mechanism.
The deck may be engagable with the lift assist mechanism when the deck is orientated in a range of engageable angles.
The range of engageable angles may include decline angles.
In one embodiment, a treadmill includes a deck, a base frame pivotally attached to the base frame, a lift motor attached to the deck and attached to the base frame, and a gas spring that offloads a portion of the lifting force from the lift motor when the lift motor changes an elevation of a portion of the deck. The deck may be declinable to a decline angle between zero degrees and negative 15 degrees and the deck may be engagable with the lift assist mechanism when the deck is orientated in a decline angle.
For purposes of this disclosure, the term “aligned” means parallel, substantially parallel, or forming an angle of less than 35.0 degrees. For purposes of this disclosure, the term “transverse” means perpendicular, substantially perpendicular, or forming an angle between 55.0 and 125.0 degrees. Also, for purposes of this disclosure, the term “length” means the longest dimension of an object. Also, for purposes of this disclosure, the term “width” means the dimension of an object from side to side. Often, the width of an object is transverse the object's length. Also for the purposes of this disclosure, the term “range of engageable angles” refers to a range of deck angles where the deck can be in contact with the list assist mechanism. For the purposes of this disclosure, a deck angle that places a portion of the deck above the lift assist mechanism so that a gap separates the lift assist mechanism from the deck so that the lift assist mechanism and the deck are not make mechanical contact may be outside of the range of engageable angles. Further, an example of a deck angle within the range of engageable angles may include an angle that places the deck so that the deck is in mechanical contact with the lift assist mechanism. Further, an deck angle that places the deck so that the lift assist mechanism can make contact and apply a load onto the deck may also be an example of an engageable angle. Also, for the purposes of this disclosure, an “inclined angle” generally refers to a deck angle where the front portion of the deck is higher than a rear portion of the deck. Additionally, for the purposes of this disclosure, a “declined angle” generally refers to a deck angle where the rear portion of the deck is higher than a front portion of the deck.
A first side post 112 is attached to a first side of the base member 106, and a second side post is attached to a second side of the base member 106. In the example depicted in
The incline mechanism for adjusting the angle of the deck 202 includes a lift motor 210. The lift motor 210 is attached to the base portion 208 of the frame. The lift motor 210 is connected to a threaded rod member 212, which is connected to the underside of the deck 202 at a first pivot connection 214. The lift motor 210 may also be pivotally connected to the base portion 208 of the frame. The deck 202 may be inclined by rotating the lift motor is a first direction which causes the threaded rod member 212 to move in a first direction.
In addition to the incline mechanism, a lift assist mechanism is incorporated into the treadmill 200 to offload a portion of the load on the incline mechanism. The lift assist mechanism may offload a portion of the load when the incline mechanism is dynamically changing the angle of the deck. In other examples, the lift assist mechanism may also offload a portion of the load from the incline mechanism when the deck is held stationary.
In some cases, the lift assist mechanism includes a gas spring 216, but any appropriate type of lift assist mechanism may be used in accordance with the principles described in the present disclosure. The gas spring 216 may include a first end 218 attached to the underside of the deck 202 and a second end 220 attached the base portion 208 of the frame.
The incline mechanism 614 is attached to the underside of the deck 610 and to the base portion 606 of the frame. Further, the incline mechanism 614 can move the deck 610 from a first angle to a second angle without assistance from the lift assist mechanism 602. When the angle of the deck 610 places the deck at angles above the lift assist mechanism 602, the deck may not contact the lift assist mechanism 602. At these higher angles, the incline mechanism may have a sufficient moment arm to move the deck due to the length of the threaded rod member 616 of the incline mechanism 614. At the lower angles, the length of the threaded rod member 616 is shorter, which increases the load on the incline motor due to a smaller moment arm. In those inclined angle ranges where the load is highest on the lift motor or other type of incline mechanism, the lift assist mechanism 602 may be engageable with the deck 610.
In the illustrated example, the coiled spring 704, without an externally applied load, has a full height. When the deck 706 is lowered onto the coiled spring 704, the coiled spring 704 provides a continuous upward force on the deck 706. This upward force offloads the load on the lift motor 708 for moving or maintaining the angle of the deck 706.
In general, the invention disclosed herein may provide users with an exercise machine that lowers the load on a lift motor of a treadmill. Conventionally, a lift motor carries the weight of the deck and the user positioned on the deck when raising and lowering portions of the deck. While the weight of the user is variable, users can range from 100 to 350 pounds. When the weight of the deck and speed of changing the angle is considered, a substantial load can be exerted by the lift motor when adjusting the orientation of the deck. To prolong the useful life of the lift motor, a lift assist mechanism can be incorporated into the lift mechanism of the deck to offload at least some of the load on the lift motor when raising and lowering portions of the deck.
Some conventional treadmills include a gas spring that assists a user when the user lifts up on the rear end of the treadmill's deck to rotate the deck from a substantially horizontal, operating position to a substantially vertical, storage position. In these examples, the deck often rotates about a pivot axis located in a front portion of the deck, and the user provides the lifting force that raises the rear end of the deck. The gas spring exerts an additional force that offloads some of the force that the user has to exert to raise the rear end of the deck, but the force exerted by the gas spring is generally not sufficient to reorient the deck from the substantially horizontal, operational position to the substantially vertical, storage position by itself
In contrast, the principles described in the present disclosure are directed towards assisting the lift motor to re-angle the deck from one operating position to another operating position. In some examples, this re-angling occurs while a user is performing an exercise on the deck. Under these circumstances, the front portion of the deck is raised or lowered while the rear end of the deck rotates about a pivot connection. The lift motor, not the user, is the power source that controls the deck angle. In those applications where the user has instructed the treadmill to execute a program that causes the deck's angle to change during the course of the exercise, the lift assist mechanism may offload the forces to be generated by the lift motor. Thus, the lift assist mechanism may prevent the lift motor from overheating and/or wearing out. In some cases, the lift motor may be prevented from raising and lowering the deck when the lift motor reaches a threshold temperature so that the lift motor can cool down. Under these circumstances, the lift motor is prevented from raising and lowering the front portion of the deck too frequently during the course of an exercise program. Thus, by providing the lift assist mechanism to offload a portion of the load exerted by the lift motor, the lift assist mechanism can increase the frequency at which the treadmill deck is reoriented, which may increase the range of exercise programs that can be executed with the treadmill. For example, certain workout programs may involve reorienting the deck frequently and would cause the lift motor to increase to a temperature where the lift motor does not operate. By incorporating the lift assist mechanism, the treadmill becomes enabled to execute these additional programs that the treadmill may not have been able to execute without the lift assist mechanism.
In some examples, the treadmill includes a frame with a base portion and an upright portion. The upright portion may include a console, handles for the user to grip during the performance of an exercise, sensors, other features, or combinations thereof. The base portion of the frame may provide beams to which the deck is movablely attached. For example, the rear portion of the deck may be pivotally attached to a base portion of the frame. In other examples, the base portion of the frame is shorter than the length of the deck. Thus, in those examples where the deck can rotate into a substantially vertical, storage position, the overall length of the treadmill deck may decrease when the deck is rotated into the storage position.
A deck may be attached to the frame, and a tread belt may be incorporated into the deck. The frame may include a base portion that supports the deck on a support surface, such as a floor. A front pulley may be connected to a front portion of the deck, and a rear pulley may be connected to a rear portion of the deck. A tread belt surrounds the front pulley and the second pulley. A drive motor can drive either the front pulley or the rear pulley and cause the tread belt to move along a surface of the deck. The speed of the tread belt may be adjustable based on the motor's output. In some cases, the user can select the tread belt's speed through an input incorporated into the treadmill.
The motor may be located inside of a motor housing. The motor housing may also house the motor's drive shaft, a flywheel, gears, cooling mechanism, and other components. In some cases, at least a portion of the lift motor and/or lift assist mechanism are also disposed within the housing. But, alternatively, the lift motor is located outside of the housing.
The drive motor may be disposed adjacent to a pulley that moves the tread belt in a rotational direction. The drive motor may be attached to the pulley with a drive shaft. A power supply may provide power to the motor to drive the rotation of the drive shaft. The power supply may be an external source, such as an alternating current system incorporated into a residence or other building, a generator, an alternative power source, another type power source, or combinations thereof. In some instances, the power supply may be internal to the housing and/or treadmill. In some cases, a flywheel is attached to and coaxial with the drive motor. The flywheel may rotate with the drive motor.
The treadmill may include an incline mechanism that is integrated into the base portion of the frame and controls an elevation of the front portion of the deck. The rear portion of the deck may be connected to the base portion at a pivot connection. As the incline mechanism changes the elevation of the front portion of the deck, the rear portion of the deck may remain connected to the base, thus, the front portion of the deck inclines with respect to the base.
The incline mechanism may include a lift motor that is connected to the deck and to the base frame of the treadmill. When activated, the lift motor may cause a rod to extend and/or move downward, which pushes against the front portion of the deck and the base frame. This may cause the front portion of the deck to raise. In other situations, when the lift motor is activated, the rod is retracted and/or moved in an opposite direction, which causes the front portion of the deck to lower. With the movement of the rod in this direction, the lift motor may cause the front end of the deck to decline. While this example has been described with having a lift motor as part of a system for inclining the deck, any appropriate mechanism may be used to incline the deck.
In some examples, the upright structure includes a first post and a second post. The first post and the second post may include a console. The console may include an input mechanism that controls an operational parameter of the treadmill. In some cases, the console includes a cooling mechanism (e.g. fan), speakers, microphones, sensors, other features, or combinations thereof. In some cases, the console includes a display.
In some cases, the treadmill includes a console. The console may locate input mechanism within a convenient reach of the user to control the operating parameters of the exercise deck. For example, the control console may include controls to adjust the speed of the tread belt, adjust a volume of a speaker integrated into the treadmill, adjust an incline angle of the running deck, adjust a decline of the running deck, adjust a lateral tilt of the running deck, select an exercise setting, control a timer, change a view on a display of the control console, monitor the user's heart rate or other physiological parameters during the workout, perform other tasks, or combinations thereof. Buttons, levers, touch screens, voice commands, or other mechanisms may be incorporated into the control console incorporated into the treadmill and can be used to control the capabilities mentioned above. Information relating to these functions may be presented to the user through the display. For example, a calorie count, a timer, a distance, a selected program, an incline angle, a decline angle, a lateral tilt angle, another type of information, or combinations thereof may be presented to the user through the display.
The exercise machine may collect data about the user's physiological condition during the performance of an exercise. In some cases, sensors are incorporated into the exercise machine to gather specific types of physiological information about the user. These sensors may be located on the exercise machine where the user comes into contact with the exercise machine. For example, an electrical contact that is part of a heart rate monitoring system may be incorporated into hand rails, handles, or other types of supports incorporated into the exercise machine. The electrical contacts may detect electrical pulses transmitted through the user's body during the exercise, and these measurements may be used to determine the user's heart rate.
An input mechanism incorporated into the deck may allow the user to select the angle of the deck. In some examples, the input mechanism includes push buttons, levers, dials, touch screens, voice commend recognition, speech command recognition, other input mechanisms or combinations thereof In some instances, in addition to controlling the lengthwise angle of the deck, the deck may also tilt from side to side, and the user may be able to control the side to side tilt.
In some cases, the treadmill may include preprogrammed workouts that simulate an outdoor route, real world route, an extra-terrestrial route, another type of route, or combinations thereof. For example, the user may input instructions through the control console, a mobile device, another type of device, or combinations thereof to select a course from a map. This map may be a map of real world roads, mountain sides, hiking trails, beaches, golf courses, scenic destinations, other types of locations with real world routes, or combinations thereof. In response to the user's selection, the display of the control console may visually depict the beginning of the selected route. The user may observe details about the location, such as the route's terrain and scenery. In some examples, the display presents a video or a still frame taken of the selected area that represents how the route looked when the video was taken. In other examples, the video or still frame is modified in the display to account for changes to the route's location, such as real time weather, recent construction, and so forth. Further, the display may also add simulated features to the display, such as simulated vehicular traffic, simulated flora, simulated fauna, simulated spectators, simulated competitors, or other types of simulated features. While the various types of routes have been described as being presented through the display of the control console, the route may be presented through another type of display, such as a home entertainment system, a nearby television, a mobile device, another type of display, or combinations thereof.
In addition to simulating the route through a visual presentation of a display, the treadmill may also modify the orientation of the running deck to match the inclines and slopes of the route. For example, if the beginning of the simulated route is on an uphill slope, the running deck may be caused to alter its orientation to raise the front portion of the running deck. Likewise, if the beginning of the simulated route is on a downward slope, the rear portion of the running deck may be caused to elevate to simulate the decline in the route. Also, if the route has a lateral tilt angle, the running deck may be tilted laterally to the appropriate side of the running deck to mimic the lateral tilt angle.
The incline mechanism may be used to raise and lower the front portion of the deck. In some cases, the incline mechanism includes a lift motor. The lift motor may include a first end that is attached to any appropriate portion of the deck, and a second end that is attached to the base portion of the frame. The lift motor may be connected to a rod that expands and/or moves resulting in displacing the front portion of the deck. In one particular example, the rod is a threaded rod member that is rotatable by the lift motor. When the lift motor is activated to rotate in a first direction, the threaded rod member moves in an upward direction and causes the front portion of the deck to raise. Similarly, when the lift motor rotates in a second direction that is opposite the first direction, the tread rod member moves in a downward direction causing the deck to lower.
The incline mechanism of the lift motor may be pivotally connected to the deck. In some cases, the first end of the incline mechanism is connected to the underside of the deck. The first end of the incline mechanism may be connected to the front portion of the deck, a middle portion of the deck, and/or a rear portion of the deck. The second end of the incline mechanism may be pivotally attached to any appropriate location on the base portion of the treadmill's frame.
The lift assist mechanism may include any appropriate type of assistance compatible with the principles described in the present disclosure. In some examples, the lift assist mechanism includes a gas spring. The gas spring may include a first part and a second part that moves telescopically or otherwise moves with respect to the first part. The gas spring may include a chamber that is filled with a compressible gas. The chamber may be collectively defined by the inside surfaces of the first part and the second part. When the first part and the second are moved towards each other so that the chamber gets smaller, the gas within the chamber is compressed. The gas spring may work by building up pressure inside the chamber making the internal pressure much greater than that of its surroundings.
The gas spring may be connected to the base portion of the frame at a connection end. In some cases, the connection end includes an opening defined in the end that can receive a fastener that connects the first end to a portion of the base frame. In some cases, the fastener is a pivot rod about which the first end can rotate. The gas spring may extend towards, but may not reach, the underside of the deck when the deck is elevated above a certain height. In this type of example, the incline mechanism may be attached to the underside of the deck and to the base portion of the frame. Further, the incline mechanism can move the deck from a first angle to a second angle without assistance from the lift assist mechanism. When the angle of the deck places the deck at angles above the lift assist mechanism, the deck may not contact the lift assist mechanism. At these higher angles, the incline mechanism may have a sufficient moment arm to move the deck due to the length of the threaded rod member of the incline mechanism. At the lower angles, the length of the threaded rod member is shorter, which increases the load on the incline motor due to a smaller moment arm. In those incline angle ranges where the load is highest on the lift motor or other type of incline mechanism, the lift assist mechanism may be engageable with the deck.
The deck may transition away from receiving support from lift assist mechanism at any appropriate transition angle. In some examples, the transition angle is between negative 15 degrees and positive 30 degrees. In other examples, the transition angle is between negative 10 degrees and positive 25 degrees. In yet another example, the transition angle is between negative 5 degrees and positive 20 degrees. In yet another example, the transition angle is between o degrees and positive 15 degrees. In an additional example, the transition angle is between positive 5 degrees and positive 10 degrees.
In some cases, the deck is engaged with the lift assist mechanism for those angles under positive 30 degrees, positive 25 degrees, positive 20 degrees, positive 15 degrees, positive 10 degrees, positive 5 degrees, zero degrees, negative 5 degrees, negative 10 degrees, negative 15 degrees, another appropriate degree, or combinations thereof.
In one example, the lift assist mechanism is in contact with the deck when the deck is in a range of engageable angles that includes declined angles, substantially neutral angles, and slightly inclined angles. Within this range of engageable angles, the length of the threaded rod member cause the moment arm to be small enough that a higher load is placed on the incline mechanism. The lift assist mechanism can offload some of the weight of the deck when the moment arm is lower. As the incline mechanism raises the deck, the incline mechanism may lift the deck off of the lift assist mechanism when the lift assist mechanism reaches it full length. As the deck rises, the load on the lift motor progressively lowers because the threaded rod member increases in length and the moment arm provides a mechanical advantage for lifting the deck. At the height when the deck lifts off of the lift assist mechanism, the length of the threaded rod member may be long enough that the moment arm lowers the load on the lift motor or other incline mechanism. In the other direction, the incline mechanism may move the deck above the lift assist mechanism. In those situations where the incline mechanism lowers the deck, the load on the lift motor progressively increases. As the load increases as the deck is lowered, the incline mechanism may lower the deck onto the lift assist mechanism which offloads a portion of the load on the incline mechanism.
In some cases, where the deck is in a declined angle, the threaded rod member of the incline mechanism may be aligned with the length of the deck. As a result, the lift motor may be at a mechanical disadvantage to raising the deck. In these situations, the lift assist mechanism may reduce the load on the lift motor allowing for a smaller lift motor to be incorporated into the treadmill or increasing the response time of changing the angle of the deck, especially at incline angles that are substantially level or declined.
In some examples, the lift assist mechanism includes a coiled spring in lieu of a gas spring or in combination with a gas spring. In this type of example, the coiled spring can be a compression spring, a tension spring, a torsion spring, another type of spring, or combinations thereof. The coiled spring, without an externally applied load, may have a full height. When the deck is lowered onto the coiled spring, the coiled spring provides a continuous upward force on the deck. This upward force offloads the load on the lift motor for moving or maintaining the angle of the deck.
In some examples, the incline mechanism is located underneath the deck, and the lift assist mechanism is, at least partially, located above the deck. In this example, the lift assist mechanism includes a first part that is connected to the deck and a second part that is connected to at least one of the posts of the upright structure. In this case, when the deck is raised, the lift assist mechanism shortens and the incline mechanism lengthens. In this case, when the deck is lowered, the lift assist mechanism lengthen and the incline mechanism shortens.
The lift mechanism may include multiple gas springs, multiple coil springs, other types of lift mechanisms, or combinations thereof. In one example, the lift assist mechanism includes a first gas spring attached to the underside of the deck at a first end and attached to a base portion of the frame at a second end. Further, a second gas spring is attached to the underside of the deck at a first end and attached to a base portion of the frame at a second end. The first gas spring and the second gas spring may be transversely arranged with respect to each other forming a cross, may be aligned with each other, or are otherwise arranged.
Further, in some cases, the lift assist mechanism may include a cable secured to at least one of the posts of the upright structure. A pulley and/or motor may be incorporated into or at least attached to the post. The cable motor may cause the pulley to rotate in a first direction to provide an upward force on the deck and rotate in a second direction to allow the deck to lower.
While the examples above has been described with reference to the lift assist mechanism being described with specific lift features, any appropriate type of lift assist mechanism may be incorporated into the treadmill in accordance with the principles described in the present disclosure. For example, the lift assist mechanism may be an electronically controlled lift mechanism that is activated when a sensor indicates that a threshold load is being applied to the incline mechanism. In some cases, the lift assist mechanism includes a magnetic mechanism.
While the examples above have been described with an incline mechanism that includes a threaded rod member and a lift motor, any appropriate type of incline mechanism may be used in accordance with the principles described in the present disclosure. For example, the incline mechanism may include, but not limited to, gas springs, cable and pulley systems, hydraulic springs, hydraulic mechanisms, lift motors, magnetic mechanisms, rack and pinions, gear assemblies, other incline mechanisms, or combinations thereof. Further, the incline mechanism is not necessarily disposed under the deck. In some cases, the incline mechanism is disposed at the side of the deck or above the deck. Further, while the examples above have been described with a lift motor having a threaded rod member, any appropriate type of rod may be used in accordance with the principles described herein. For example, the rod may by linearly disposed with a liquid or gas based on pressure within an internal chamber and the lift motor controls the amount of pressure within the chamber. Other types of linear actuators may be compatible with the principles described in the present disclosure.
It should be noted that the methods described above describe possible implementations, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible. Furthermore, aspects from two or more of the methods may be combined.
Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof
The description herein is provided to enable a person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples described herein, but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.
This application claims priority to U.S. patent application Ser. No. 62/429,981 titled “Offsetting Treadmill Deck Weight During Operation” and filed on 5 Dec. 2016, which application is herein incorporated by reference for all that it discloses.
Number | Date | Country | |
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62429981 | Dec 2016 | US |