CEDAR RAPIDS — Adam Todd, adjusting like many Iowans to a social-distanced lifestyle since the novel coronavirus hit, celebrated a milestone 21st birthday with a drive-by parade Friday evening.

Todd, best known for being ABC World News Tonight Person of the Week in 2016, stood outside the Cedar Rapids house where he lives with his parents, Dale Todd, a Cedar Rapids City Council member, and Sara Todd, watching the cars drive by wishing him a happy birthday.

“My son has a bigger following than I would ever hope to have,” Dale Todd said. “Everybody knows he loves a parade. He loves the trucks and cars and people that are a part of that.

“There’s no better example that ‘it takes a village.’ He has had a team for 21 years.”

Todd, who will be graduating from Washington High School in Cedar Rapids, has Lennox-Gastaut Syndrome, a severe form of epilepsy.

The parade was arranged by his mother, Sara, who invited friends and teachers to drive by between 5 and 6 p.m. to wave, shout happy birthday, hold up a sign, sing a song or do a dance, all from a safe distance — “whatever they’re able to,” she said.

Sara said Adam would have finished his last semester of education had the coronavirus not cut the school year short.

“That makes it extra special,” Sara said. “He hasn’t really gotten to say goodbye to his friends and teachers.

“We have appreciated his teachers so much. They have been a part of his team and really a part of our family.”

Adam, a member of the Washington High School junior varsity track team, captured national attention in 2016 when, during a cross-country race at Noelridge Park, he became distracted and veered from the course. Evan Hansen, a runner from Iowa City High, loped after him and guided him back to the track.

They ran the last mile together, the last two to cross the finish line.

That show of compassion and sportsmanship is what led to ABC News picking both of them as Persons of the Week.

In addition to Friday’s parade, Adam celebrated his birthday by taking his service dog, Turbo, on a run and trying to spot trains. He and his mom saw two.

“It was a good day,” Sara said.

Adam’s birthday cake, made by a family friend, was decorated with a train and a golden retriever that looks like Turbo.

“We were trying to think of a creative way we can help Adam have fun and celebrate him,” Sara said. “He deserves it.”

Comments: (319) 368-8664; grace.king@thegazette.com

When Olympic gold medallist Shona McCallin was hit on the side of her head by a seemingly innocuous shoulder challenge, she suffered what was originally thought to be a concussion.

Adam thanks you — his blog viewers and supporters — and encourages you to continue the discussion and awareness raising about TBI and PTSD; the battle does not stop here.

Willems et al.'s fundamental lemma asserts that all trajectories of a linear system can be obtained from a single given one, assuming that a persistency of excitation condition holds. This result has profound implications for system identification and data-driven control, and has seen a revival over the last few years. The purpose of this paper is to extend Willems' lemma to the situation where multiple (possibly short) system trajectories are given instead of a single long one. To this end, we introduce a notion of collective persistency of excitation. We will then show that all trajectories of a linear system can be obtained from a given finite number of trajectories, as long as these are collectively persistently exciting. We will demonstrate that this result enables the identification of linear systems from data sets with missing data samples. Additionally, we show that the result is of practical significance in data-driven control of unstable systems.

We define local indices for projective umbilics and godrons (also called cusps of Gauss) on generic smooth surfaces in projective 3-space. By means of these indices, we provide formulas that relate the algebraic numbers of those characteristic points on a surface (and on domains of the surface) with the Euler characteristic of that surface (resp. of those domains). These relations determine the possible coexistences of projective umbilics and godrons on the surface. Our study is based on a "fundamental cubic form" for which we provide a closed simple expression.

We establish versions of Conley's (i) fundamental theorem and (ii) decomposition theorem for a broad class of hybrid dynamical systems. The hybrid version of (i) asserts that a globally-defined "hybrid complete Lyapunov function" exists for every hybrid system in this class. Motivated by mechanics and control settings where physical or engineered events cause abrupt changes in a system's governing dynamics, our results apply to a large class of Lagrangian hybrid systems (with impacts) studied extensively in the robotics literature. Viewed formally, these results generalize those of Conley and Franks for continuous-time and discrete-time dynamical systems, respectively, on metric spaces. However, we furnish specific examples illustrating how our statement of sufficient conditions represents merely an early step in the longer project of establishing what formal assumptions can and cannot endow hybrid systems models with the topologically well characterized partitions of limit behavior that make Conley's theory so valuable in those classical settings.

According to one embodiment, a glass container may include a body formed from a Type I, Class B glass composition according to ASTM Standard E438-92. The body may have an inner surface, an outer surface and a wall thickness extending between the outer surface and the inner surface. The body may also include a compressively stressed layer extending into the wall thickness from at least one of the outer surface and the inner surface. A lubricous coating may be positioned on at least a portion of the outer surface of the body, wherein the outer surface of the body with the lubricous coating has a coefficient of friction less than or equal to 0.7.

The present disclosure provides reagents that can be used to label synthetic oligonucleotides with rhodamine dyes or dye networks that contain rhodamine dyes.

Systems and methods for controlling the damping of magnetic media for heat assisted magnetic recording are provided. One such system includes a heat sink layer, a growth layer on the heat sink layer, a magnetic recording layer on the growth layer, where the growth layer is configured to facilitate a growth of a preselected crystalline structure of the magnetic recording layer, and a capping magnetic recording layer on the magnetic recording layer, the capping recording layer including a first material configured to increase a damping constant of the capping recording layer to a first preselected level.

A combustion chamber is provided and includes a combustion device and a supply circuit arranged to feed fuel at a plurality of locations of the combustion device. The supply circuit includes manifolds collecting fuel to be distributed among at least some of the locations, ducts extending from the manifolds and feeding the locations. Some of the ducts carry valves having a plurality of predetermined working positions, each working position corresponding to a different fuel flow through the valve.

A hydraulic damper for providing fluid damping to a tensioner in a drive system that includes a damper cup, which is mounted to the tensioner and configured to rotate about a central axle in tandem with the tensioner, an end plate having an outer face and an inner face, which is attached to the damper cup forming a fluid chamber, a peg attached to the end plate and extending away from the inner face and toward the damping cup, a damping fluid, which is contained within the fluid chamber, a plurality of shear plates housed within the fluid chamber comprising alternating fixed plates engaged with a fixed component of the tensioner and rotatable plates engaged with a rotatable component of the tensioner where the peg extends through openings in each of the shear plates allowing for rotation of the rotatable plate with the rotation of the peg.

A slotted inverse tap, compressible for insertion past damaged entry threads in blind holes. (FIG. 1 thru FIG. 5) The tool can be made to smaller sizes than that of prior art. An elongate slot (23) proceeds through a first threaded end (21), then well into a reduced diameter cylindrical body (25). After insertion to the hole bottom, a tabbed shim (28) is inserted to the slot from its side, then pressed down until stopped. The shim (28) enforces mating engagement with undamaged internal threads. A second end of hex and/or squared or other configuration facilitates use of a tap wrench or other tool for rotational extraction. Damaged threads are reformed/re-cut upon rotational withdrawal.

A tool stocker includes main stockers for holding a plurality of tools detachably mounted on a main spindle for machining a workpiece, an auxiliary stocker for holding and transferring tools to and from the main stockers, and a tool transfer mechanism for transferring tools between the main stockers and the auxiliary stocker. The auxiliary stocker includes a plurality of tool pods for removably supporting the tools therein, a rail in sliding engagement with outer surfaces of the tool pods, a chain for moving the tool pods in sliding engagement with the rail, and a motor for actuating the chain. The rail has a recess defined therein in alignment with the tool transfer mechanism, such that the tools transferred by the tool transfer mechanism pass through the recess.

A constant velocity joint including an outer race having inner and outer surfaces, the inner surface including a plurality of outer bail tracks. The constant velocity joint also includes an inner race having a plurality of inner ball tracks which correspond to the outer ball tracks, a ball cage disposed between the outer race and the inner race, a plurality of balls arranged within the ball cage and contacting the outer ball tracks and the inner ball tracks. A damping assembly is connected to the outer race.

A device for damping vibrations in a drive train, in particular for plug screws in the pulp and paper industries. The device is principally characterized in that a cylindrical shaft, preferably designed as a hollow shaft, is provided, wherein the cylindrical shaft is arranged between the halves of a coupling and at least one ring having friction surfaces is arranged around the cylindrical shaft. Stick-slip vibrations that occur can thereby be favorably eliminated, and thus the gearbox and the motor of the drive train can be protected.

A rotational vibration damper includes a primary side (32) and a secondary side (46) which is rotatable with respect to the primary side (32) around an axis of rotation (A) against the action of a damper element arrangement (28). At least one damper element unit (42) of the first group (70) and at least one damper element unit (42') of the second group (70') are pre-loaded, and the primary side (32) and the secondary side (46) are pre-loaded in a basic relative rotation position with respect to one another. Proceeding from the basic relative rotation position of the primary side (32) with respect to the secondary side (46), a pre-loading path (V, V') of at least one pre-loaded damper element unit (42) is shorter than a maximum relative rotation path of the primary side (32) with respect to the secondary side (46).

A damper device configured with an input element, an intermediate element to which power is transferred from the input element through a first elastic body, and an output element to which power is transferred from the intermediate element through a second elastic body. One of the output element and the intermediate element has a protruding portion projecting in an axial direction. The other one of the output element and the intermediate element has a cutout portion corresponding to the protruding portion. The protruding portion has a restricting portion that is engaged with the cutout portion in a rotation direction so as to restrict rotation of the intermediate element relative to the output element, and a support portion that is engaged with the cutout portion so that the intermediate element is supported by the output element in a radial direction.

A propshaft assembly that includes a tubular member, first and second end connections coupled to opposite ends of the tubular member and a damper that is received in the tubular member and positioned between the first and second end connections. The tubular member has a wall member that defines an interior circumferential surface. The damper has a first damping device, a second damping device and a third damping device. The first damping device has a first core and a first damping member that is fixed to the first core. The first damping member extends helically about the first core and engages the interior circumferential surface. The second damping device is formed of foam and is positioned in the tubular member between the first and third damping devices. The second damping device engages the interior circumferential surface. The third damping device has a second core and a second damping member that is fixed to the second core. The second damping member extends helically about the second core and engages the interior circumferential surface.

A novel information storage device is disclosed and claimed. The information storage device includes a device housing with a generally rectangular bay to accommodate a disk drive. The generally rectangular bay includes a base portion and a plurality of side portions. The information storage device further includes a damping insert sheet disposed between the disk drive and the base portion. The damping insert sheet has a plurality of elastomeric cushions, for example with a cushion thickness in the range 0.5 mm to 10 mm, and a spanning sheet, for example having a sheet thickness in the range 0.02 mm to 0.35 mm. Each of the plurality of elastomeric cushions is attached to the spanning sheet. Each of the plurality of elastomeric cushions contacts and is compressed between the generally rectangular bay and the disk drive.

Various embodiments concern a DSA suspension of a disk drive. The DSA suspension comprises a support configured to attach to the disk drive, the support comprising a proximal portion, a distal portion, and a linkage portion therebetween. The DSA head suspension system further comprises at least one motor mounted on the support, each motor positioned between the proximal portion and the distal portion. The DSA suspension further comprises a damper attached to some or all of the proximal portion, the motor(s), the distal portion, and the linkage portion. The damper can be a single layer or multilayered. The damper can comprise viscoelastic material. The damper can be adhesive. The damper may only be attached to the support and the motors and not to other components of the DSA suspension.

A slider and microactuator elements are disposed on a gimbal portion of a flexure. A tongue of the gimbal portion has a first tongue portion, a second tongue portion, and a hinge portion. A leading-side portion of the slider is movably disposed on the first tongue portion. A trailing-side portion of the slider is secured to the second tongue portion. The hinge portion is formed between the first tongue portion and the second tongue portion. The gimbal portion is provided with a damper member includes a viscoelastic material layer and a constrained plate. The damper member comprises a first damper and a second damper. The hinge portion is exposed between the first damper and the second damper. A dimple on a load beam contacts the hinge portion at a point of contact.

A vibration-damping plain bearing composite comprising a sliding layer, a dimensionally stable support layer and an elastic layer. In one embodiment, the dimensionally stable support layer is arranged between the sliding layer and the elastic layer; in another embodiment, the elastic layer is arranged between the sliding layer and the dimensionally stable support layer. The bearing composites are characterized that a ratio of the thickness of the elastic layer tEL to a thickness of the sliding layer tSL is at least 3.

A vibration dampener for a camera mount is structured to reduce the movement of a first mount component relative to a second mount component. An upper camera mount component securing a camera couples to a lower camera mount component, which in turn couples to a base mount component configured to couple to a user, a sports board, a helmet, a vehicle, and the like. The vibration dampener is compressibly inserted between the lower mount component and the base mount component, causing the vibration dampener to exert an outward force on the lower mount component, and securing the lower mount component against a portion of the base mount component. The movement of the lower mount component relative to the base mount component is accordingly reduced by the vibration dampener.

A method of reducing light damage in a shutterless imaging device includes receiving a signal from a hardware device. The signal from the hardware devices is analyzed. In response to the analysis of the signal from the hardware device, a lens of the shutterless imaging device is adjusted. Adjusting the lens spreads out energy of far-field image light incident on an image sensor of the shutterless imaging device.

No flange damage wedge lock washers are disclosed. The washers may comprise an upper washer and a lower washer. The lower washer may have a generally smooth bottom surface and at least one means for securement. The at least one means for securement may be arranged to keep together the lower washer and a flange without causing damage to the flange. A locking fastener assembly which comprises no flange damage wedge lock washers is also disclosed. The locking fastener assembly may include a lower washer having a generally smooth bottom surface and at least one means for securement. A method of manufacturing a locking fastener assembly which comprises no flange damage wedge lock washers is also disclosed. The locking fastener assembly of the method may include a lower washer having a generally smooth bottom surface and at least one means for securement.

A profiled element for damping sound vibrations on rail lines including a first main surface, which is designed and dimensioned such that it can be attached as a support surface to sections of the rail web without having to provide an adhesive layer, wherein the profiled element further has at least one recess on a front surface located opposite of the support surface, wherein the at least one recess in the front surface is designed for the positive engagement of an elastic fixing element for fixing the profiled element against the rail web, and at least one widened region of the profiled element in the region of the front surface, said widened region present in the lower region of the front surface in an installed position.

A vibration damping mechanism allows increase of an absorption amount of vibration energy, with less possibilities of increase in the manufacture cost of a vibration damping weight and of reduction in the strength of a shaft section. Within a cylindrical hollow portion formed inside the shaft section, there are accommodated a plurality of weight members divided from each other along the circumferential direction about the axis of the hollow portion. An urging member is provided for urging the weight members toward the axis such that dividing faces of adjacent weight members are brought into surface contact with each other.

A tool adapter includes an adaptor body having a connection portion structured to be attached to a machine tool and a holder portion disposed opposite the connection portion and a tool receiver structured to receive and couple a portion of a rotary cutting tool therein. The tool receiver is mounted in the holder portion so as to be rotatable to a limited extent. The tool receiver is mounted in the holder so as to be elastically resilient in both the axial and circumferential directions.

An apparatus includes an inner rim, a base wall, a side wall and an outer rim. The inner rim has a first opening formed therein. The base wall extends outward from an inner edge of the inner rim and is integral with the inner rim. The side wall extends outward from an outer edge of the inner rim and is integral with the inner rim. The outer rim has a second opening formed therein and an inner edge integral with the side wall. The inner rim, base wall, side wall and outer rim are formed to prevent liquid seepage to one or more surrounding components of an appliance in which the apparatus is installed.

A vehicle collision damage mitigation system includes: a vehicle having a crashable zone on a front side of a dash panel in a vehicle longitudinal direction; a body airbag device that inflates a body airbag that is provided on a front surface of the dash panel by a pressure of gas generated by a gas generating device; a detector that detects whether a mode of a frontal collision of the vehicle is a full-overlap collision or another collision; and a control unit that operates the gas generating device when detecting a collision other than the full-overlap collision on the basis of a detection result of the detector and that does not operate the gas generating device when detecting the full-overlap collision.

Equipment protection systems, arc containment devices, and methods of assembling arc containment devices are disclosed. In one example, an electrical isolation structure includes a conductor base, a cover coupled to the conductor base and defining an isolation chamber, a containment shield disposed on the conductor base within the isolation chamber, and a biasing assembly positioned between the cover and the containment shield. The containment shield defines a containment chamber configured to enclose the plurality of electrode assemblies. The containment shield is configured to at least partially contain the arc products within the containment chamber. The biasing assembly is configured to permit the containment shield to move away from the conductor base to thereby define a gap between the conductor base and the containment shield to enable at least some of the arc gases to vent from the containment chamber.

A damping tool holder, such as a boring head, a chuck, or a milling cutting arbor, integrates a damping device (2), in the form of an elongated body. The damping device (2) is housed in a mounting body (3), connected by one end to the tool-holder body (1) and having at its other end an end fitting (4) for mounting a tool, whereby the mounting body (3) is equipped with at least one lubricant feed pipe (32), emptying at its front end into the end fitting (4) for mounting a tool and connected at its other end to a circular groove (102) for distributing lubricant that is provided on the front surface of the tool holder (1).

A method and apparatus for a fluid damper comprising a first fluid-filled chamber, a second chamber filled with a fluid having variable flow characteristics and at least partially displaceable by the first fluid, and a gas chamber, the gas chamber compressible due to the displacement of the second chamber. In one embodiment, the fluid in the second chamber is a variable rheology fluid.

A leak-proof damper with a self-diagnostic feature. An auxiliary oil reservoir body is disposed externally with respect to the damper cylinder and generally adjacent the rod seal, wherein the auxiliary oil reservoir body is concealed by an end cap. The maximum volume of oil retainable by the auxiliary oil reservoir body is predetermined to coincide with a volume of oil which may be lost from the interior of the damper cylinder and yet the damper will still function properly. The auxiliary oil reservoir body may be a seal body having an internal cavity providing an oil retention volume or an absorbent body having an absorbency capacity that provides an oil retention volume.

An air dam for a semi-truck tractor in accordance with an aspect of the present disclosure includes a rigid upper panel affixed to a bumper of the semi-truck tractor and a lower flexible panel affixed to the upper panel.

A damper system may include a handle mechanism for use with a damper actuator system. Illustratively, the handle mechanism may include a drive gear mechanism, a handle, a housing, and a spring, and may be actuated to set a crack pressure for the damper system. The handle may connect to the drive gear mechanism at a drive gear arm of the drive gear mechanism and may flip over or about the drive gear arm to move from a first position to a second position. In some instances, once the handle is in the second position, a force may be applied thereto to disengage the drive gear from a stop member and thereafter, the handle may be rotated to change the crack pressure of the damper system.

The apparatus for mounting at least one dampener and/or stabilizer to an archery bow to absorb shock and vibration realized by an archer upon the release of the archery bow. The present invention provides an elongated support structure releasably connectable to the at least one dampener and/or stabilizer. A releasable fastener is connected to one end of the support structure, and the releasable fastener is releasably connectable to the archery bow such that the support structure is extendible in a cantilevered position relative to the archery bow.

An archery bow vibration dampening and balancing device is attachable to an archery bow by means of an elongated clamp with a housing pivotably interconnected to the elongated clamp opposite the attachment point. A vibration dampening and balancing device is secured in an opening formed in the housing.

A vibration dampened barrel for a crossbow preferably includes at least two vibration dampening chambers, which extend at least a portion of a length of the vibration dampened barrel. The at least two vibration dampening chambers are at least partially filled with a vibration dampening material, such as silicone, rubber, low density foam, high density foam, or any other suitable material that absorbs noise and or vibration. The vibration dampening material is preferably applied by injection, compression, spray, pouring or any other suitable method. The vibration dampening material is retained in the at least two vibration dampening chambers by curing or hardening; mechanically confinement including the use of fasteners or a plug; or with any other suitable method. The at least two vibration dampening chambers may be partially or fully filled. The vibration dampening material may also be placed on a surface inside an extruded barrel.

An acoustic damping article includes a substrate, wherein the substrate has a surface area S. The acoustic composition further includes a polymer resin. The polymer resin coats partially the surface area with a set of areas. The ratio of the coated areas over the surface area S is less than 1 and the polymer resin coverage is not greater than about 500 g/m2.

A system for dampening fluid recovery in an ink-based digital printing system includes a seal manifold having a front seal portion, the front seal portion having an upper wall facing the imaging surface, the upper wall being configured to define an air flow channel with the imaging surface, the upper wall being contoured to form a distance between the upper wall and the imaging surface at an evaporation location that is less than distance between the upper wall and the imaging surface at locations interposing the evaporation location and a vacuum inlet channel of the seal manifold.

In a variable data lithography system that employs a patterned dampening fluid layer for image formation, dampening fluid may be removed prior to image transfer to a substrate. Removed dampening fluid may be recovered and recycled to reduce operating expenses and environmental waste. A replacement fluid may be applied after inking and after removal of the dampening fluid. The replacement fluid preferentially occupies the regions previously occupied by dampening fluid, and may lubricate the transfer nip. Any replacement fluid and ink not transferred to the substrate upon printing may then be cleaned from the print image carrier prior to forming a new dampening fluid layer and subsequent pattern formation.

A system and corresponding methods are disclosed for depositing of a layer of dampening fluid to a reimageable surface of an imaging member in a variable data lithography system by way of condensation. Dampening fluid in an airborne state is introduced proximate the reimageable surface in a condensation region. Conditions in the condensation region are such that the airborne dampening fluid preferentially condenses on the reimageable surface in a precisely controlled quantity, to thereby form a precisely controlled layer of dampening fluid of desired thickness over the reimageable surface. Among other advantages, improved print quality is obtained.

A hair clipper has a base structural housing with a blade set operably secured thereto. The blade set has a stationary blade and a reciprocating blade. The base has at least one support for a rotary motor. A flexible motor vibration and noise damper fits over half of the motor, and a motor cover is secured to the base structural housing over the vibration damper. A secondary housing cover is secured to the base structural housing over the motor cover.

A control system for an HVAC system serving at least two zones, each zone receiving conditioned air by way of a zone duct, each zone duct including a zone damper having a first portion responsive to the static pressure in a HVAC system to open and bleed an amount of conditioned air past the damper when the static pressure of the system increases above a selected level, a second portion controlled by a actuator to move between an open and a closed position in response to a zone thermostat, and a coupling mechanism coupling the first and second portions to limit the relative movements of the two portions with respect to each other, and a biasing mechanism exerting a torque against the system static pressure differential. The first portion can be a single one-piece undivided blade pivotally mounted with a shell surrounding the zone damper.

An apparatus and a method for determining a damage state of a wheel bearing (12), in which a wheel (15) with a tire (9) arranged on a rim (8) in such a manner that the wheel can be rotated on an axle, in a motor vehicle, in particular during maintenance work on the motor vehicle. In order to avoid the wheel bearing (12) being accessed unnecessarily, a sensor unit (1) which communicates with an evaluation unit and is removably fastened radially outside a screw circle (11) of the rim (8) is provided for the purpose of determining the damage state.

A mooring system for a floating structure (1) in which a floating structure or fixed tower is provided with a turntable (80). A floating structure is moored to the turntable via at least one rigid arm (51,51') and two tension members (41, 41'). The rigid arm is provided on one end with a ballast weight (61, 61') and includes a damping system formed of least two separated liquid tanks (70, 70') that are partly filled with liquids and placed at the same distance from the horizontal center line (100). The tanks (70, 70') are fluidly connected with each other so that liquid can be exchanged between the tanks damps a swinging yaw motion of the rigid arm (51, 51') around the vertical axis of the turntable (80).

A drying apparatus for temporary location within a damp or waterlogged room is disclosed. The apparatus includes sensors to sense the level of temperature and humidity within the room, a heater to provide heat for the room, an air circulation fan for selectively circulating heated air within the room or selectively exhausting warm and humid air from the room and for allowing outside ambient air into the room. The apparatus being adapted to cyclically continue until the sensed humidity reaches a required level, the apparatus thereafter indicating, directly or indirectly, the completion of the drying process. A method of drying a room using such apparatus is also disclosed which employs a technique whereby the rate of change of the temperature increase is used to determine when humid air should be exhausted from the room. A time limit can also be use to determine when said exhausting takes place.

A post for a dental crown is disclosed having improved structural features—including increased post strength and reduced likelihood of root fracture. In one embodiment, the post includes a quadrangle (4-way) split shank for increased compliance and root stress reduction while providing very high mechanical grip strength and pull-out resistance. In another embodiment, a shortened threaded section and a thread-free shank tip minimize the possibility of root fracture while still providing high grip strength and pull-out resistance. Embodiments also include a radiused transition from a primary thread to a secondary thread portion of the shank for stress reduction; and axial grooves, cross-axis through holes and other shape features of the post head for increased crown retention strength.

A driven damper assembly, comprises a first main-damper cover plate comprising an inclined portion. The inclined portion comprises a notch. A first plane passes through the first pre-damper cover plate. A second plane passes through the first main-damper cover plate and is parallel to the first plane. The notch comprises a first wall and a second wall. The first wall is not parallel to the second wall. The inclined portion extends away from the second plane at an angle greater than zero degrees away from the second plane and less than ninety degrees away from the second plane. The first pre-damper cover plate comprises a tab with a first portion extending outwardly at an angle greater than zero degrees away from the first plane and less than ninety degrees away from the first plane, wherein the tab engages the notch at the first wall and the second wall.