The present invention relates generally to the field of exercise equipment, and more specifically to exercise apparatus for aerobic, strength, and cardiovascular conditioning that permits an operator to perform an upper body spinning bike exercise.
There are numerous exercise devices, and in particular, a number of exercise cycles. Most exercise cycles are designed to condition the legs. A popular exercise to condition the legs is spinning, using a spinning bike. A spinning bike is a stationary exercise bike that includes a frame, a seat, handlebars, brake mechanism, pedals, and a flywheel connected to the pedals, typically without a clutch mechanism between the pedals and the flywheel. It is a very good exercise device for conditioning the legs, in part, because the pedals rotate when the flywheel is rotating, and vice-versa. Force is required to be applied to the pedals to accelerate the rate of rotation of the spinning flywheel, and force is required to be applied to the pedals to decelerate the rate of rotation of the spinning flywheel, thereby requiring effort on the part of the operator to accelerate and decelerate the flywheel.
There are fewer options for upper body exercise cycles. An example of one type of device designed to exercise the arms is an upper body ergometer (UBE) that uses hand pedals attached to crank arms to drive the rotation of a flywheel.
A first type of upper body ergometer is designed to accelerate a flywheel when force is applied to the hand pedals to rotate the crank arms in a first direction, and to decelerate the flywheel when force is applied to the hand pedals in a second reverse direction. The hand pedals rotate when the flywheel is spinning, and the flywheel spins when the hand pedals are rotating. The first type of upper body ergometer is similar in function to spinning bikes used for conditioning the legs.
A second type of upper body ergometer is designed with a clutch mechanism so that rotation of the hand pedals to rotate the crank arms in a first direction will accelerate the flywheel, while rotation of the hand pedals in the opposite direction will cause the crank arms to freewheel. The second type of upper body ergometer is similar to many road bikes which impart rotation to the rear wheel when the crank arms are rotated in a first direction, but which allow the crank arms to spin freely when crank arms are rotated in the reverse direction.
The first type of upper body ergometer, where the hand pedals are forced to spin any time the flywheel is spinning, provides a very good upper body exercise, because the operator expends energy and effort to both increase and decrease the rate of rotation of the flywheel. One disadvantage of the first type of upper body ergometer is that the spinning flywheel continues to spin the hand pedals, and there is inertia stored in the flywheel. The more inertia that is stored in the flywheel, the harder it is for an operator to decelerate the rotation of the hand pedals. If an operator desires to stop spinning the hand pedals, or if the operator's arms get tired, the operator must either apply a lot of effort to force the flywheel and hand pedals to stop spinning, or the operator must let go of the hand pedals and wait for friction to slow the flywheel and hand pedals to a stop.
A foot-operated brake mechanism can be used to slow or stop the rotation of the hand pedals and flywheel, but a foot-operated brake mechanism may not be a desirable solution, as upper body ergometers are often used by operators who are disabled or otherwise unable to use their legs. A hand-operated brake mechanism can be used to slow or stop the rotation of the hand pedals and flywheel, but a hand-operated brake mechanism may not be a desirable solution either, as the operator already has both hands engaged in operation of the hand pedals. The first type of upper body ergometer therefore has disadvantages.
The second type of upper body ergometer is designed to accelerate a flywheel when the hand pedals are operated to rotate the crank arms in a first direction, but to allow the crank arms to freewheel when the hand pedals are operated to rotate the crank arms in a second reverse direction. The second type of upper body ergometer provides the benefit of exercising the upper body, while allowing the operator to stop rotating the hand pedals at any time. One disadvantage of the second type of upper body ergometer is a lack of variety in the exercise, as the design limits the exercise to rotating the hand pedals under load around a single closed loop path moving in a single direction. Another disadvantage of the second type of upper body ergometer is that the muscles utilized during the course of the exercise only fire in one specific sequence as the operator rotates the pedals under load around a single closed loop path moving in a single direction. A third disadvantage of the second type of upper body ergometer is that the muscles utilized during the course of the exercise are exercised less effectively due to the fact that the muscles are restricted to pushing at specific locations along the path of travel of the hand pedals, and pulling at other specific location along the path of travel of the hand pedals.
A need remains for an exercise apparatus to exercise an operator's upper body, without the disadvantages described above.
The present invention provides an exercise apparatus and methods to allow an operator to exercise the upper body by exerting effort to rotate a pair of hand pedals about a closed loop path in a first direction or in a second reverse direction while allowing the operator to stop rotation of the hand pedals at any time.
In an exemplary embodiment of the present invention, a frame supports a flywheel, a drive unit rotatably mounted to the frame, a pair of crank arms rotatably mounted to the drive unit, and a pair of hand pedals respectively mounted to the pair of crank arms, where each hand pedal is configured to engage an operator's hand. The drive unit is configured to be rotated on the frame to allow the drive unit, the cranks arms, and the hand pedals to be rotated 180 degrees relative to the frame, so that the drive unit has a first position and a second position rotated 180 degrees from the first position. When the drive unit is in the first position, the drive unit is configured to impart rotation to the flywheel when the crank arms are rotated in a first direction, and to allow the crank arms to freewheel when the crank arms are rotated in a second reverse direction. When the drive unit is in the second position, rotated 180 degrees from the first position, the drive unit is reversed on the frame, and the operation of the exercise apparatus is substantially reversed. In other words, when the drive unit is in the second position, the drive unit is configured to impart rotation to the flywheel when the crank arms are rotated in the second direction, and to allow the crank arms to freewheel when the crank arms are rotated in the first direction.
The present invention may also include a seat to support the operator, a resistance device to impede rotation of the flywheel, and a locking mechanism to lock the drive unit into at least the first position and the second position. The seat of the exercise apparatus may be removable to allow access by an operator using a wheelchair, or the seat may be removed to allow an operator to stand while using the exercise apparatus.
This summary is not meant to be exhaustive. Further features, aspects, and advantages of the present invention will become better understood with reference to the following description, accompanying drawings and appended claims.
a is a perspective view of the drive unit of the exercise apparatus of
b is the perspective view of
a is a perspective view of the drive unit of the exercise apparatus of
b is the perspective view of
Referring now specifically to the figures, in which identical or similar parts are designated by the same reference numerals throughout, a detailed description of the present invention is given. It should be understood that the following detailed description relates to the best presently known embodiment of the invention. However, the present invention can assume numerous other embodiments, as will become apparent to those skilled in the art, without departing from the appended claims.
An exercise apparatus constructed according to the principles of the present invention is designated as 100 in
The crank arms 160 include a first crank arm 161 and a second crank arm 162. The pair of hand pedals 170 include a first hand pedal 171 mounted to the first crank arm 161 and a second hand pedal 172 mounted to the second crank arm 162. The drive unit 150 has an upper portion 152 and a lower portion 154. Each crank arm 161, 162 is rotatably connected to the upper portion 152 of the drive unit 150, and both crank arms 161, 162 are configured to be rotated about the second axis 120. To use the exercise apparatus 100, an operator grasps the hand pedals 170 and starts to rotate at least one crank arm 160 about the second axis 120. The flywheel 130 is rotatably connected to the lower portion 154 of the drive unit 150, and the drive unit 150 is configured such that the rotation of either crank arm 161, 162 in a first direction imparts rotation to the flywheel 130, and rotation of either crank arm 161, 162 in a second direction causes the respective crank arm 161, 162 to freewheel, so that rotation of either crank arm 161, 162 in the second direction does not impart rotation to the flywheel 130. The operator may grasp the hand pedals 170 and rotate either crank arm 161, 162 or both crank arms 160 in the first direction to impart rotation to the flywheel 130, and the operator may stop rotation of either crank arm 161, 162 or both crank arms 160 at any time while the flywheel 130 continues to rotate.
To impart rotation to the flywheel 130, the operator must apply force to at least one hand pedal 171, 172 to rotate at least one crank arm 161, 162 in the first direction. The operator engages muscles in the upper body to apply force to impart rotation to the flywheel 130, thereby exercising the upper body. When the operator chooses to rest, the operator stops rotating one or both crank arms 160.
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a-7b show a close-up of the drive unit 150. Referring to
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Additionally, a base structure 106 is shown attached to the frame 105. The base structure 106 is configured to support a typical wheelchair, and is shown having a contoured surface with ramps at both the front and back portions of the base structure 106. The ramps at the back portion of the base structure 106 chock the wheels of a wheelchair positioned on the base structure 106 so that an operator using a wheelchair is able to stably position a wheelchair on the base structure 106 before using the exercise apparatus 100. In other words, an operator who is using a wheelchair, and who is pushing and pulling on the hand pedals 171, 172 might typically have to worry that the hand pedals 171, 172 would exert an equal and opposite reaction on the operator in the wheelchair, causing the wheelchair to move around during operation of the exercise apparatus 100, but due to the configuration of the base structure 106, the wheelchair is stably positioned on the base structure 106.
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The locking mechanism 140 works by allowing the shaft 144 to move axially along the first axis 110 in addition to allowing the shaft 144 to rotate about the first axis 110. When the lever 141 is rotated up into the unlocked position (as shown in
When the lever 141 is rotated down into the locked position (as shown in
The shaft 144 is constrained to rotate about the first axis 110 and move in the axial direction along the first axis 110 by the housing 149. The stop feature 144a interacts with the housing 149 to limit the range of rotation about the first axis 110. The bearing surface 145 is shaped like a washer and is positioned around the shaft 144. The bearing surface 145 is supported by the housing 149. The shaft 144 has a bore hole through the center of the shaft 144 and perpendicular to the axial direction. The eccentric cam 142 is inserted into the bore hole in the shaft 144, and a follower wheel 143 is attached to either end of the eccentric cam 142 such that the two follower wheels 143 are free to rotate about the eccentric cam 142 and the two follower wheels 143 are in rolling contact with the bearing surface 145 and are supported by the bearing surface 145. The lever 141 is attached to the eccentric cam 142 by a bolt 141a so that rotation of the lever 141 rotates the eccentric cam 142. A cap 151 covers the top of the locking mechanism 140 and is held in place by a screw 151a.
The operator may rotate the lever 141 to rotate the eccentric cam 142, thereby either raising or lowering the shaft 144. The shaft 144 is attached at its lower end to the drive unit 150, so that raising or lowering the shaft 144 also respectively raises or lowers the drive unit 150. When the drive unit 150 is in its lowest position, the tapered engagement feature 154a is disengaged from the mating feature 149a on the housing 149, allowing the drive unit 150 and shaft 144 to rotate about the first axis 110. As the shaft 144 rotates about the first axis 110, the lever 141, the eccentric cam 142, and the two follower wheels 143 also rotate about the first axis 110. The follower wheels 143 are configured to roll on the bearing surface 145 such that the eccentric cam 142 and the shaft 144 are free to rotate about the first axis 110 with very little friction.
The shaft 144 has a stop feature 144a which interacts with the housing 149 to limit the range of rotated of the shaft 144 about the first axis 110. The stop feature 144a is configured so that at a first stop position, the drive unit 150 is in the first position, and the tapered engagement feature 154a on the drive unit 150 is aligned with the mating feature 149a on the housing 149. The stop feature 144a is configured so that at a second stop position, the drive unit 150 is in the second position, and the tapered engagement feature 154a on the drive unit 150 is again aligned with the mating feature 149a on the housing 149.
When the drive unit 150 is in either the first position or the second position and the tapered engagement feature 154a on the drive unit 150 is aligned with the mating feature 149a on the housing 149, the operator may rotate the lever 141 to rotate the eccentric cam 142 to raise the shaft 144 into its highest position. The shaft 144 is attached at its lower end to the drive unit 150, so that raising the shaft 144 into its highest position also raises the drive unit 150 into its highest position. The tapered engagement feature 154a on the drive unit 150 is raised until it is engaged with the mating feature 149a. When the tapered engagement feature 154a is engaged with the mating feature 149a, the shaft 144 and the drive unit 150 are locked in place, and the drive unit 150 is constrained from rotating about the first axis 110.
If the eccentric cam 142 merely raised the shaft 144 and drive unit 150 until the tapered engagement feature 154a was engaged with the mating feature 149a, the weight of the drive unit 150 pulling downward on the shaft 144 would have a tendency to rotate the eccentric cam 142 backward into the unlocked position, thus lowering the shaft 144 to its lowest position. The drive unit 150 stores potential energy as the weight of the drive unit 150 is raised, and loses potential energy as the weight of the drive unit 150 is lowered. If the locking mechanism 140 is designed so that no potential energy needs to be added to disengage the locking mechanism 140 from the fully locked position will tend to be unstable, allowing the locking mechanism 140 to drop from the locked position into the unlocked position. Conversely, any design that requires the addition of potential energy to disengage the locking mechanism 140 from the fully locked position will tend to stably retain the locking mechanism 140 in the locked position. The eccentric cam 142 needs to be configured to stably retain the shaft 144 in its highest position. One possible way to stably retain the shaft 144 in its highest position is to configure the eccentric cam 142 so that rotation of the eccentric cam 142 toward the locked position raises the shaft 144 to its highest point and then slightly lowers the shaft 144 as the eccentric cam 142 is rotated into the fully locked position. In other words, to disengage the eccentric cam 142 from the locked position, rotation of the eccentric cam 142 in a direction to unlock the locking mechanism 140 must first raise the shaft 144 before lowering the shaft 144 into its lowest position.
While an eccentric cam 142 configured to slightly drop the shaft 144 downward as the eccentric cam 142 is rotated into the fully engaged locked position creates a stable locked position, it causes one of two possible problems. A first possible problem is encountered if the eccentric cam 142 is configured to locate the shaft 144 in its highest position when the locking mechanism 140 is in its fully locked position. In this scenario, the eccentric cam 142 positions the shaft 144 and drive unit 150 at the proper height to firmly engage the tapered engagement feature 154a with the mating feature 149a, but the shaft 144 has nowhere to go to be raised from this fully locked position. The shaft 144 cannot be raised any higher once the tapered engagement feature 154a is fully engaged with the mating feature 149a, so the locking mechanism 140 is not truly in a stably locked position. A second possible problem is encountered if the eccentric cam 142 is configured to locate the shaft 144 in a location slightly below its highest position when the locking mechanism 140 is in its fully locked position, and the eccentric cam 142 is configured to locate the shaft 144 in its highest position as the locking mechanism 140 moves from its fully locked position toward its unlocked position. In this scenario, when the locking mechanism 140 is in the fully locked position, the eccentric cam 142 drops the shaft 144 downward slightly from its highest position, so that the tapered engagement feature 154a is not firmly engaged with the mating feature 149a, thereby allowing a little bit of play between the drive unit 150 and the frame 105. Play or rotation between the drive unit 150 and the frame 105 is undesirable when the locking mechanism 140 is in a fully locked configuration, so while this locking mechanism 140 would stably retain locking mechanism 140 in the fully locked position in this scenario, the tapered engagement feature 154a would not be fully engaged with the mating feature 149a, and the drive unit 150 would be able to move relative to the frame 105.
The addition of a spring washer 146 allows the locking mechanism 140 to fully engage the tapered engagement feature 154a with the mating feature 149a when the locking mechanism 140 is in the fully locked position, while still allowing the eccentric cam 142 to be configured to stably retain the locking mechanism 140 in the fully locked position. A spring washer 146 and threaded support surface 147 located beneath the bearing surface 145 allows the bearing surface 145 to move downward, instead of requiring an overconstrained shaft 144 to move upward after the tapered engagement feature 154a is fully engaged with the mating feature 149a.
The threaded support surface 147 is positioned within the housing 149 to provide support for the spring washer 146. The bearing surface 145 is placed in contact with the spring washer 146. The position of the threaded support surface 147 is adjustable, allowing fine control of the position of the spring washer 146 and the bearing surface 145 during the assembly process. The rest of the components of the locking mechanism 140 are assembled as described before.
The addition of the spring washer 146 does not change the operation of the locking mechanism 140 when the locking mechanism 140 is unlocked. In other words, the lever 141 is rotated to rotate the eccentric cam 142 into the unlocked position, lowering the shaft 144 to its lowest position, causing the tapered engagement feature 154a on the drive unit 150 to disengage from the mating feature 149a. In this unlocked state, the drive unit 150 and shaft 144 are free to rotate about the first axis 110.
During engagement of the locking mechanism 140, the lever 141 is rotated to rotate the eccentric cam 142 toward the locked position. As the eccentric cam 142 is rotated, the eccentric cam 142 raises the shaft 144 and drive unit 150 until the tapered engagement feature 154a becomes fully engaged with the mating feature 149a. Once the tapered engagement feature 154a becomes fully engaged with the mating feature 149a, the shaft 144 cannot move upward any more. As the eccentric cam 142 continues to be rotated toward the locked position, the eccentric cam 142 pushes the two follower wheels 143 downward on the bearing surface 145, which in turn compresses the spring washer 146.
The spring washer 146 stores energy as it is compressed, and releases energy as it is uncompressed. As the eccentric cam 142 continues to be rotated toward the locked position, the spring washer 146 continues to be compressed and continues to store energy until the eccentric cam 142 reaches a maximum offset position. As the eccentric cam 142 is rotated into its fully locked position, the eccentric cam 142 rotates away from the maximum offset position, and the spring washer 146 starts to expand, releasing some of the energy stored in the spring washer 146. When the locking mechanism 140 is in the fully locked position, the tapered engagement feature 154a is fully engaged with the mating feature 149a so that there is no play or rotation between the drive unit 150 and the frame 105, and the eccentric cam 142 is stably positioned in the fully locked position. The cam stop 142a prevents any further rotation of the eccentric cam 142 once the eccentric cam 142 has reached the fully locked position, and the eccentric cam 142 can only be rotated in the direction to disengage the locking mechanism 140.
With the addition of the spring washer 146, the locking mechanism 140 has three basic operating regimes. The first operating regime is when the locking mechanism 140 is in a disengaged state, where the spring washer 146 is in an uncompressed state, the shaft 144 and the drive unit 150 are lowered by the eccentric cam 142 so that the tapered engagement feature 154a is disengaged from the mating feature 149a, and the drive unit 150 is free to rotate about the first axis 110. The second operating regime is when the locking mechanism 140 is in a partially engaged state, where the shaft 144 and the drive unit 150 are raised by the eccentric cam 142 so that the tapered engagement feature 154a is engaged with the mating feature 149a, constraining the drive unit 150 so that the drive unit 150 is no longer able to rotate about the first axis 110, but the spring washer 146 is still in an uncompressed state so that the spring washer 146 is not applying a clamping force to maintain the engagement between the tapered engagement feature 154a and the mating feature 149a. The third operating regime is when the locking mechanism 140 is in a fully engaged state, where the shaft 144 and the drive unit 150 are raised by the eccentric cam 142 so that the tapered engagement feature 154a is engaged with the mating feature 149a, constraining the drive unit 150 so that the drive unit 150 is no longer able to rotate about the first axis 110, and the spring washer 146 is in an at least partially compressed state so that the spring washer 146 is applying a clamping force to maintain the engagement between the tapered engagement feature 154a and the mating feature 149a. In addition, the eccentric cam 142 is configured so that as the locking mechanism 140 moves from the partially engaged state to the fully engaged state, the eccentric cam 142 passes through a maximum offset position. The spring washer 146 goes from an uncompressed state to a maximum compressed state and back to partially compressed state as the locking mechanism 140 moves from the partially engaged state to the fully engaged state. The maximum compressed state of the spring washer 146 occurs as the eccentric cam 142 passes through the maximum offset position, and the partially compressed state of the spring washer 146 is less compressed than the maximum compressed state.
To disengage the locking mechanism 140 from the fully locked position requires that the eccentric cam 142 rotates back toward the maximum offset position, thus further compressing the spring washer 146, the spring washer 146 going from a partially compressed state to the maximum compressed state, and requiring an energy input to compress the spring washer 146. The requirement for energy to be input into the spring washer 146 to rotate the eccentric cam 142 from the fully locked position to the maximum offset position is what causes the locking mechanism 140 to be stably positioned in the fully locked position.
The threaded support surface 147 supplies an adjustment mechanism to fine tune the amount that the spring washer 146 is compressed when the eccentric cam 142 is in the fully locked position, as well as when the eccentric cam 142 is rotated into the maximum offset position. During assembly of the locking mechanism 140, rotating the threaded support surface 147 adjusts the position of the threaded support surface 147 up or down, setting the distance between the threaded support surface 147 and the mating feature 149a. The position of the threaded support surface 147 locates the spring washer 146 and the bearing surface 145 within the locking mechanism 140, and adjusts the amount of effort required by the operator of the exercise apparatus 100 to engage the eccentric cam 142 into the fully locked position, or disengage the eccentric cam 142 from the fully locked position. To limit the ability of the threaded support surface 147 to move after assembly, a locking ring 148 is added between the threaded support surface 147 and the housing 149. The locking ring 148 is attached to the threaded support surface 147 with a set screw (not shown) and the locking ring 148 is configured such that the locking ring 148 is prevented from rotating within the housing 149. The locking ring 148 prevents the threaded support surface 147 from rotating, thus preventing the threaded support surface 147 from changing its position within the housing 149 once the locking mechanism 140 is assembled.
It should be noted that a specific embodiment of a locking mechanism 140 has been described; however, different locking mechanisms could be used while remaining within the scope and spirit of the invention.
A method of performing an upper body spinning exercise having a frame 105, a first hand pedal 171 and a second hand pedal 172, a drive unit 150 pivotally mounted to the frame 105 for rotation about a first axis 110, a pair of crank arms 161, 162 pivotally mounted to the drive unit 150 about a second axis 120 and respectively connected to the hand pedals 171, 172, and having a flywheel 130, is to grasp at least one hand pedal 171, 172, then to rotate the hand pedal 171, 172 about a closed loop path about a second axis 120 in a first direction to impart rotation to the flywheel 130, and then to release the hand pedal 171, 172. Then, rotate the drive unit 150 about the first axis 110 from a first position to a second position to reverse the positions of the hand pedals 171, 172 and the crank arms 161, 162, then grasp at least one hand pedal 171, 172, and rotate the hand pedal 171, 172 around a closed loop path about the second axis 120 in a second direction opposite to the first direction to impart rotation to the flywheel 130.
The method of performing the upper body spinning exercise does not require that the same hand pedal 171, 172 be grasped both before and after the drive unit 150 has been rotated about the first axis 110. For instance, it is quite possible to grasp a first hand pedal 171 with the left hand, rotate the first hand pedal 171 about a closed loop path about a second axis 120 in a first direction to impart rotation to the flywheel 130, and then release the first hand pedal 171. Next, rotate the drive unit 150 about the first axis 110 from a first position to a second position to reverse the positions of the hand pedals 171, 172 and the crank arms 161, 162. Finally, grasp the second hand pedal 172 with the left hand, and rotate the second hand pedal 172 around a closed loop path about the second axis 120 in a second direction opposite to the first direction to impart rotation to the flywheel 130.
Similarly, the method of performing the upper body spinning exercise does not require that the same hand be used to grasp the same hand pedal 171, 172. For instance, it is possible to grasp a first hand pedal 171 with the left hand, rotate the first hand pedal 171 about a closed loop path about a second axis 120 in a first direction to impart rotation to the flywheel 130, and then release the first hand pedal 171. Next, rotate the drive unit 150 about the first axis 110 from a first position to a second position to reverse the positions of the hand pedals 171, 172 and the crank arms 161, 162. Finally, grasp the first hand pedal 171 with the right hand, and rotate the first hand pedal 171 around a closed loop path about the second axis 120 in a second direction opposite to the first direction to impart rotation to the flywheel 130.
The method also allows both hand pedals 171, 172 to be rotated simultaneously to impart rotation to the flywheel 130, or for both hand pedals 171, 172 to be grasped by an operator while only one hand pedal 171, 172 is rotated to impart rotation to the flywheel 130.
It is possible for the operator to rotate a first hand pedal 171 in a first direction about the second axis 120, while rotating a second hand pedal 172 in a second direction about the second axis 120. Or it is possible for the operator to rotate the first hand pedal 171 at a first rate in a first direction about the second axis 120, while rotating the second hand pedal 172 at a second rate in a first direction about the second axis 120.
Each hand pedal 171, 172 rotates its respective crank arm 161, 162 about the second axis 120, and each crank arm 161, 162 can rotate independently of the other crank arm 161, 162, therefore, the method allows either crank arm 161, 162 to be rotated about the second axis 120 in either a first or a second direction, so that the two crank arms 161, 162 may be aligned with one another, or oriented so that there is an angle between the first crank arm 161 and the second crank arm 162. Additionally, the method allows that the angle between the two crank arms 161, 162 may be changed at any time by the operator.
While the present invention has been described in terms of certain preferred embodiments, additions, deletions, substitutions, modifications and improvements can be made while remaining within the scope and spirit of the invention as defined by the following claims.
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