US20130234561A1

US20130234561A1 - High Speed Smart Material Actuator with Second Stage

Info

Publication number: US20130234561A1
Application number: US13/884,824
Authority: US
Inventors: Jeffery B. Moler
Original assignee: Viking AT LLC
Current assignee: Viking AT LLC
Priority date: 2010-12-09
Filing date: 2011-12-09
Publication date: 2013-09-12
Also published as: WO2012118548A2; EP2649658A2; EP2649718A4; KR20130132528A; EP2649718A2; US20130234562A1; KR20130132527A; WO2012079012A2; JP2014504135A; US8729774B2; EP2649658A4; JP2014508489A; WO2012118548A3; WO2012079012A3

Abstract

A smart material actuator apparatus having a smart material device, compensator, movable supporting member, two mechanical webs, two actuating arms, and a second stage assembly. Application of an electrical potential causes the smart material device to expand, thereby moving the actuating arms. That movement causes resilient strips to urge a second stage attachment surface in a direction substantially parallel to the smart material device. Optional dampening assemblies may be added where high speed operation is desired, and an optional valve assembly may be attached where an actuated valve, such as a high speed actuated air valve, is needed.

Description

BACKGROUND

This application claims priority to provisional application No. 61/421,504 filed Dec. 9, 2010, which is incorporated herein in its entirety.
The present invention relates to a smart material actuator apparatus adapted to operate at high speed and incorporating a second stage assembly adapted to translate inward or outward movement of the actuating arms to linear movement of a second stage centerpiece.
Certain smart material actuators are known in the art. Such actuators, however, are not adapted to high speed operation for reasons including lower than desirable resonant frequencies and rebound effects. Additionally, prior art smart material actuators are either direct-acting (meaning that the smart material device itself actuates the component to be actuated), or mechanically amplified (meaning mechanical webs or other mechanical amplification means is utilized to increase the stroke length so that it is greater than the expansion of smart material device itself). Where mechanical amplification was utilized, however, the resulting motion was not in the same direction as the direction of expansion of the smart material device.
The present invention addresses those concerns by providing a mechanically amplified smart material actuator apparatus, embodiments of which are capable of operation at very high speeds, and in which the direction of actuation is substantially parallel to the expansion of the smart material. Such actuators are desirable in a variety of applications including, without limitation, in sorting machines in which a stream of material is passed through a passageway with a sensor adapted to detect faulty particles as they pass. An air valve is then activated to expel the faulty particle from the stream as it passes. Allowing for the air valve to be activated and deactivated at higher speeds allows greater throughput through the passage. Accordingly, a higher speed, mechanically amplified smart material actuator according to the present invention is well suited for such applications as it allows for both high speed operation and a convenient configuration as the direction of actuation is substantially parallel with the smart material itself.
This application hereby incorporates by reference, in their entirety, provisional applications Nos. 61/551,530, 61/452,856, 61/504,174 as well as PCT/US2010/041727, PCT/US10/041461, PCT/US2010/47931, PCT/US2011/25292, PCT/US2011/25299, U.S. patent application Ser. Nos. 13/203,737, 13/203,729, 13/203,743 and 13/203,345, and U.S. Patents:
U.S. Pat. No. 6,717,332;
U.S. Pat. No. 6,548,938;
U.S. Pat. No. 6,737,788;
U.S. Pat. No. 6,836,056;
U.S. Pat. No. 6,879,087;
U.S. Pat. No. 6,759,790;
U.S. Pat. No. 7,132,781;
U.S. Pat. No. 7,126,259;
U.S. Pat. No. 6,924,586
U.S. Pat. No. 6,870,305;

SUMMARY

The present invention discloses an actuator apparatus comprising a smart material device, a compensator, a movable supporting member, two mechanical webs, two actuating arms, and a second stage assembly. The mechanical webs comprise a first resilient member operably attached to the compensator and a second resilient member attached to the movable supporting member. The movable supporting member comprises a first mounting surface and the smart material device is affixed between the first mounting surface and the compensator, with the optional inclusion of a spacer. The actuating arms comprise a first actuating arm end attached to one mechanical web and an opposed second actuating arm end attached to the second stage assembly. The second stage assembly comprises resilient strips having a first resilient strip end attached to the second actuating arm end and a second resilient strip end operably connected to a second stage attachment surface. Application of an electrical potential causes the smart material device to expand, thereby urging the movable supporting member away from the compensator and causing the first and second resilient members to flex, thereby moving the actuating arms. That movement causes the resilient strips to urge the second stage attachment surface in a direction substantially parallel to the smart material device. Optional dampening assemblies may be added where high speed operation is desired, and an optional valve assembly may be attached where an actuated valve is needed.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features in the invention will become apparent from the attached drawings, which illustrate certain preferred embodiments of the apparatus of this invention, wherein

FIG. 1 is a front, sectional view of a preferred embodiment of the actuator assembly of the apparatus of the present invention;

FIG. 2 is a perspective view of the embodiment shown in FIG. 1;

FIG. 3 is a front, sectional view of the embodiment shown in FIG. 1 adapted to operate an air valve assembly;

FIG. 4 is a detailed sectional view of the dampener assembly utilized in the embodiment illustrated in FIG. 1;

FIG. 5 is a graph showing oscillation of an actuator assembly of the present invention without dampener assemblies installed;

FIG. 6 is a graph showing oscillation an actuator assembly of the present invention with dampener assemblies installed;

FIG. 7 is a front view of an embodiment of an actuator assembly of the present invention having an external case (shown sectionally) with integrated dampeners and adapted to operate an air valve assembly;

FIG. 8 is a detail, perspective view of the attachment between the actuator assembly and the air valve assembly in the embodiment illustrated in FIG. 7; and

FIG. 9 is a front view of a preferred embodiment of an actuator assembly according to the present invention having reversed actuating arms, a reversed one-piece second stage assembly, and no dampener assemblies.

DETAILED DESCRIPTION

While the following describes preferred embodiments of this invention, it is understood that this description is to be considered only as illustrative of the principles of the invention and is not to be limitative thereof, as numerous other variations, all within the scope of the invention, will readily occur to others.
It will be noted that in the illustrated embodiments, different embodiments comprise the same or similar components. This is preferred as it reduces manufacturing and repair costs by allowing for use of interchangeable parts, and also allows for assembly of a broader variety of actuator assemblies. Where the same component is suitable for use in different embodiments, the same reference number is used. For example, and without limitation, actuating arm 114 is illustrated as a common component that may be used in embodiments including 100, 400 and 500. Accordingly, the same number is used to indicate the common part used in the illustration of each. Where components in different embodiments have a similar structure, but are not necessarily common parts, a prime is used. For example, and without limitation, attachable compensator 103 serves the same function as integral compensator 103′. Although similar, compensators 103 and 103′ are distinguishable in that one is attachable and the other is a portion of an integrated component. Accordingly, the same element number is utilized with prime notation to indicate distinct variations.
Herein, the following terms shall have the following meanings:
The term “adapted” shall mean sized, shaped, configured, dimensioned, oriented and arranged as appropriate.
The term “smart material device” shall mean a device comprising a material that expands when an electric potential is applied or generates an electric charge when mechanical force is applied. Smart material devices include, without limitation, devices formed of alternating layers of ceramic piezoelectric material fired together (a so-called co-fired multilayer ceramic piezoelectric stack such as those available from suppliers including NEC) or a device formed of one or more layers of material cut from single crystal piezoelectric materials. In the foregoing, the term “piezoelectric material” also includes so-called “smart materials,” sometimes created by doping known piezoelectric materials to change their electrical or mechanical properties.
The term “mechanical web” shall mean a structure comprising at least two resilient members and being adapted to translate motion to an actuating arm. Motion is translated by applying a force that causes the resilient members to flex. The resilient nature of the resilient members, however, indicates that they will return to substantially their original configuration upon removal of that force. There are a wide variety of materials that may be used to form resilient members, including, without limitation, steel, stainless steel, aluminum, carbon fiber, plastic and fiberglass.
The term “activation” when used in conjunction with “actuator” or “smart material device” means application of an electrical potential and current suitable to cause the smart material device to expand in an amount sufficient to flex the compliant members of at least one mechanical web of the actuator apparatus.
The term “valve stem” means any structure capable of operating a valve mechanism including without limitation the axial rod attached to a poppet valve or any spool, diaphragm or similar or related structure capable of operating a valve. In the context of the current invention, an actuated valve is opened and/or closed when an actuator applies force to a valve stem.
The definitions and meanings of other terms herein shall be apparent from the following description, the figures, and the context in which the terms are used.
The task of designing an actuator, smart material or otherwise, that is capable of operating at high speed, including speeds in the range of 500 to 5,000 operations per second, presents numerous challenges. One such challenge is that the actuator may resonate at high operational speeds as is further described in the incorporated references. A second challenge is that operation at speed may cause the moving components of the actuator to over-extend or over-rebound or fatigue prematurely.
Embodiments of the present invention address these challenges by providing a smart material actuator capable of sustained high speed operation, a preferred embodiment of which is suitable for operation of a high speed air valve. The combination of actuator and air valve is adapted for operation in a sorting machine in which air pressure is used to eject defective items from a stream and requires operational speeds in the range of 0 to 1,200 bursts per second. As will be understood by those of skill in the art, however, there are myriad applications for actuators adapted to operate at high speed and the present invention shall not be limited to the specific embodiments or applications herein described.
The task of designing a smart material actuator also presents challenges with respect to the degree and direction of motion achieved. If the action of the smart material that provides the motive force is not amplified, only a limited stroke can be achieved. For applications requiring a longer stroke, mechanical amplification may be used (as is also described in the incorporated references). Such designs, however, tend to produce motion that is orthogonal to, or at a non-zero angle with respect to, the motion of the smart material device. It is sometimes more convenient to have amplified motion in the same direction as the expansion of the smart material device itself.
Referring to the figures, FIG. 1 illustrates a cut-away view of an embodiment of the actuator apparatus of the present invention with FIG. 2 illustrating a perspective view of the embodiment in FIG. 1 in solid form, but without smart material device 102 installed. In the illustrated embodiment, actuator assembly 100 comprises second stage assembly 180 attached to actuating arms 114. A smart material device 102 is situated within compensator 103 between first mounting surface 108 and optional spacer 106. Smart material device 102 comprises electrode 104 which may conveniently extend through first mounting surface 108. Compensator 103 acts as a fixed supporting member such that substantially upon application of an appropriate electrical potential smart material device 102 expands, urging first mounting surface 108 on movable supporting member 109 away from compensator 103. As movable supporting member 109 moves, first resilient member 110 and second resilient member 111 of mechanicals webs 113 flex, thereby moving actuating arms 114. In the embodiments illustrated, second actuating arm ends 116 move toward smart material device 102. Mechanical webs 113 may suitably be constructed from stainless steel or another material with sufficient strength and resilience, as is discussed further in the incorporated references. Compensator 103 may be constructed of any suitably rigid material (such as without limitation carbon fiber, steel, aluminum, or stainless steel) and may be operably attached to first resilient members 110 by mechanical connection as illustrated, or by making compensator 103′ integral to mechanical webs 113 such that they are formed as a single part (see FIG. 7). Where high speed operation is desired, actuating arms 114, however, are preferably formed of a lighter weight material such as carbon fiber, and may be attached to mechanical webs 113 with mechanical fasteners 112 which may conveniently be machine screws. Lighter weight actuating arms 114 are preferred where high speed operation is needed as they increase the resonant frequency of the actuator apparatus 100, as is discussed further in the incorporated references. In applications in which the frequency of actuation is not necessarily constant, such as the sorting machine application described above, it is desirable that the resonance frequency be higher than the maximum expected frequency of actuation. Otherwise resonance effects could cause excessive flexing of first resilient members 110 and second resilient members 111 and/or other damaging effects, thereby limiting the working life of the assembly. While carbon fiber is a convenient material to use for actuating arms 114 as it is both strong and light in weight, thereby assisting in efforts to increase the resonant frequency of the assembly, other materials may also be used including, without limitation aluminum, steel, stainless steel, fiberglass and plastic. The weight of actuating arms 114 may also be lessened through the use of hollow or u-shaped designs such as those described in the incorporated references.
Actuating arms 114 are connected to second stage assembly 180. Second stage assembly 180 converts the motion of second actuating arm ends 116 to a substantially linear movement substantially parallel to the direction of expansion of smart material device 102. Second stage assembly 180 comprises resilient strips 182 which may conveniently be strips of steel, spring steel, carbon fiber, fiberglass, plastic, stainless steel or aluminum. First resilient strip end 181 attaches to second actuating arm end 116. This may be accomplished with any variety of mechanical or adhesive connection, including the use of pins 183 that pass through first resilient strip end 181 as shown in the figure.
Second resilient strip ends 185 are operably connected to second stage attachment surface 184. This may also be accomplished with any variety of mechanical or adhesive connection, including the use of pins 187 that pass through second resilient strip end 185 as shown in the figure. Second stage attachment surface 184 may conveniently be a block formed of carbon fiber, steel, spring steel, fiberglass, plastic, stainless steel or aluminum, and comprises a means 186 to connect to an apparatus to be actuated. As illustrated, means 186 is a hole suitable for receiving a valve stem (not illustrated) as is further described below. Other means may also be utilized including any suitable combination of mechanical fasteners or clamps, or adhesives, as will be readily understood by those of ordinary skill in the art. In this way, when actuating arms 114 move inward, resilient strips 182 urge second stage attachment surface 184 in a direction substantially parallel to smart material device 102. When actuating arms 114 return back outward, resilient strips 182 urge second stage attachment surface 184 back toward its original position. Where high speed operation is required, second stage attachment surface 184 is also preferably formed of a light weight material such as carbon fiber, which helps increase the resonant frequency of the apparatus.
Actuator assembly 100 further comprises dampener assemblies 150, which are shown in greater detail in FIG. 4. Dampener assemblies 150 are preferred for high speed operation as they both act to prevent over extension of actuating arms 114 and also serve to dampen ringing which can, in certain circumstances, damage the actuator assembly or limit the maximum operational frequency. Referring to FIG. 4, dampener assemblies 150 comprise set screw 152 which passes through outer pliable stop 154, through actuating arm 114, through inner pliable stop 156, which is situated between actuating arm 114 and compensator 103, and into compensator 103. The passage through actuating arm 114 is adapted to allow free movement of actuating arm 114 about dampener assembly 150, while the head of set screw 152 and outer pliable stop 154 are adapted to resist over-extension of actuating arm 114. In this way dampener assemblies 150 can be attached to compensator 103 (preferably through a threaded or welded connection) and movably attached to actuating arms 114. Stopper nuts 158 serve both to position and secure inner pliable stop 156 and to secure set screw 152 to compensator 103. By tightening stopper nuts 158 against each other and against compensator 153, unwanted loosening and tightening of set screw 152 and unwanted movement of inner compliant stop 156 can be minimized.
During operation, actuating arms 114 move between inner pliable stop 156 and outer pliable stop 154. At the intended movement limits, inner pliable stop 156 and outer pliable stop 154 are impacted by actuating arm 114 and will preferably yield to absorb shock. Accordingly, inner pliable stop 154 and outer pliable stop 156 may conveniently be formed of a compliant but resilient material such as Buna rubber or other similar materials known in the art. The result is that actuating arms 114 are prevented from over-extension in either direction and vibrations created by the impact of actuating arms 114 at either end of their movement range are dampened.
As has been discussed, for high speed operation, it is desirable to have an actuator assembly 100 with a high resonant frequency. It is also desirable to reduce ringing. The change in momentum when the actuating arms 114 are moving quickly with the rapid expansion of smart material device 102, and then suddenly stopped, can be very rapid. The natural spring tendencies of the assembly can cause spring force in the return direction, thereby promoting a dampening oscillation back and forth, as well as potential overshooting. This is in part because the momentum in actuating arms 114 is such that they may not stop immediately when smart material device 102 reaches its expansion or contraction limits. Ringing is exacerbated near resonance, which occurs at the natural oscillating frequency of the physical device. Ringing, like resonance, can create undesirable and potentially damaging vibrations. Thus, a light weight overall structure increases the resonant frequency, and the use of dampener assemblies 150 serves to dampen ringing.
FIGS. 5 and 6 illustrate the dampening effect dampener assemblies 150 have on ringing behavior. FIG. 5 illustrates the natural ringing behavior of an actuator assembly without dampener assemblies 150, whereas FIG. 6 illustrates the behavior of an actuator assembly with dampener assemblies 150. Note that after oscillation is initiated at first initiation point 304 in FIG. 5, a naturally dampening oscillation occurs as would normally be expected. However, when oscillation is initiated at second initiation point 324 in FIG. 6, there is a significant reduction in oscillation and, hence, ringing when dampener assemblies 150 are utilized.
The dampening effect achieved with dampener assemblies 150 has a further effect. During the period of time in which actuating arms 114 come into contact with inner pliable stop 156 and outer pliable stop 154, the overall system is stiffer and has a higher resonant frequency.
It will be clear to those of ordinary skill in the art that dampener assemblies 150 are but one means of dampening oscillation appropriate for use in embodiments of the present invention. Other means may also be used including, without limitation, replacing inner pliable stop 156 and outer pliable stop 154 with a flat elastomer or a spring. More complex molded shapes could also be used, as well as placement of stopping means in a surrounding casing, as is illustrated in FIG. 7.
Referring to FIG. 7, actuator assembly 400 is essentially identical to actuator assembly 100 except that it is mounted within outer casing 402. Outer casing 402 may be of any suitable material including without limitation aluminum, steel, plastic or fiberglass. Inner dampening posts 256 and outer dampening posts 254 are adapted such that actuating arms 114 are prevented from moving beyond predetermined locations. Inner dampening posts 256 and outer dampening posts 254 may conveniently be formed as part of outer casing 402 or may be attached to it. Surrounding inner dampening posts 256 and outer dampening posts 254 with Buna rubber, an elastomer, or a similar pliable material enables them to operate in a manner substantially similar to the operation of inner pliable stop 156 and outer pliable stop 154 of dampener assemblies 150. Outer casing 402 may be formed in a clamshell configuration or left open, depending on the environment in which it is needed to operate.
Further illustrated in FIG. 7, is compensator 103′. Compensator 103′ is serves the same function as compensator 103, but instead of being attached to first resilient member 110 mechanically, it is formed integral to mechanical webs 113 as part of a single component.
FIG. 3 illustrates an embodiment of the actuator assembly of the present invention adapted to operate an air valve assembly 200. It is understood that actuator apparatuses according to the present invention may also serve many other purposes; the illustration of air valve assembly 200 merely being illustrative of one appropriate application. Many other applications and attachment structures will be apparent to those of skill in the art, all within the scope of the present invention.
Air valve assembly 200 comprises valve casing 206, within which valve 212 operably attached to valve stem 204 is mounted. Pressurized air, or any other appropriately pressurized gas, vapor or fluid, enters valve inlet 208. When valve 212 is raised by valve stem 204, the pressurized air or other gas, vapor or liquid, is expelled from valve outlet 210. As illustrated, valve stem 204 operably connects to second stage attachment surface 184. Such connection can be made through use of a press-fit, threaded fastener, weld, adhesive, or any of a variety of connecting means known to those of skill in the art. Mounting bracket 202, which is further illustrated in FIG. 8, attaches valve casing 206 to compensator 103,103′ preferably by way of threaded mechanical fasteners 191. Forming mounting bracket 202 in a U-shape allows resilient strips 182 and second stage attachment surface 184 to move freely while air valve assembly 200 remains fixedly attached to compensator 103, 103′. In this way, activation of actuator apparatus 100 causes valve 212 to open and closed at appropriate times. Where pressurized air is used, a brief burst of air may thus be generated. The higher the speed at which actuator assembly 100 is capable of operating, the shorter the duration of air burst is possible.
In light of the foregoing description and the incorporated references, it will be understood by those of ordinary skill in the art that embodiments of the present invention may include actuating arms 114 of different lengths, or that extend away from compensator 103, 103′ or that are adapted such that they are not substantially parallel to smart material device 102 and, instead, are adapted and mounted such that the angle between the central axis of smart material device 102 and actuating arms 114 ranges from zero to ninety degrees (with angles of zero degrees and between thirty and sixty degrees being suitable for various applications) in embodiments in which actuating arms 114 extend toward compensator 103, 103′, and ranges from ninety to one hundred eighty degrees (with angles of one hundred eighty degrees and between one hundred twenty and one hundred fifty degrees being suitable for various applications) in embodiments in which actuating arms 114 extend away from compensator 103, 103′
It will be further understood that second stage assemblies 180, 180′ (illustrated in FIG. 9) may also be adapted to be of different lengths and to have different angles with respect to actuating arms 114. This not only allows for the use of actuating arms 114 adapted to be mounted at an angle, it also allows for adjustment of the stroke length and force. Based on the geometry of the desired configuration, an actuator apparatus with a second stage assembly angled such that it extends further away from second actuating arm ends 116 can be expected to generate greater force, but with a shorter stroke length. Similarly, an actuator apparatus with a second stage assembly angled such that it does not extend as far away from second actuating arm ends 116 can be expected to have a greater stroke length, with a somewhat reduced force.
It will be still further understood that with actuating arms 114 of suitable length, second stage assemblies 180, 180′ may be mounted to extend outward from second actuating arm ends 114 or inward from second actuating arm ends 114. By reversing second stage assembly 180, 180′, the direction of motion upon activation and deactivation of the actuator apparatus can be reversed.
Referring to FIG. 9, an embodiment of the actuator apparatus of the present invention is illustrated in which actuator apparatus 500 (illustrated without smart material device 102 installed) is adapted such that actuating arms 114 extend away from compensator 103′ at an angle of one hundred eighty degrees. In such configurations, substantially upon activation of actuator apparatus 500, second actuating arm ends 116 are urged apart. Second stage assembly 180′ is mounted to extend inward from second actuating arm ends 114. Thus, when second actuating arm ends 116 move apart, second stage attachment surface 184′ moves outward, and when second actuating arm ends 116 move together, second stage attachment surface 184′ moves inward.
Second stage assembly 180′, as illustrated, differs from second stage assembly 180 in that resilient strips 182′ and second stage attachment surface 184′ are integral as opposed to being mechanically attached. Such embodiments may be manufactured by forming second stage assembly 180′ from a single piece of material (such as spring steel) and forming bends such that the desired angles result. Such embodiments can be both lighter and easier to manufacture than embodiments having mechanically attached second stage attachment surfaces 184.
In light of the foregoing description, the embodiments of the present invention can be seen to include an actuator apparatus 100 comprising a smart material device 102, a compensator 103, 103′, a movable supporting member 109, two mechanical webs 113, two actuating arms 114, and a second stage assembly 180, 180′ wherein (a) said mechanical webs 113 comprise a first resilient member 110 operably attached to said compensator 103, 103′ and a second resilient member 111 attached to said movable supporting member 109; (b) said movable supporting member 109 comprises a first mounting surface 108; (c) said smart material device 102 is affixed between said first mounting surface 108 and said compensator 103, 103′; (d) said actuating arms 114 comprise a first actuating arm end 115 attached or integral to one said mechanical web 113 and an opposed second actuating arm end 116 attached to said second stage assembly 180, 180′; and (e) said second stage assembly 180, 180′ comprises resilient strips 182, 182′ having a first resilient strip end 181, 181′ attached to said second actuating arm end 116 and a second resilient strip end 185, 185′ operably connected to a second stage attachment surface 184, 184′ wherein application of an electrical potential causes said smart material device 102 to expand, thereby urging said movable supporting member 109 away from said compensator 103, 103′ and causing said first and second resilient members 110, 111 to flex, thereby moving said actuating arms 114 and causing said resilient strips 182, 182′ to urge said second stage attachment surface 184, 184′ in a direction substantially parallel to said smart material device 102.
Embodiments of such an actuator apparatus of are also convenient wherein said resilient strips 182, 182′ are formed of a material selected from the group consisting of steel, spring steel, carbon fiber, fiberglass, plastic, stainless steel, and aluminum.
Embodiments of such an actuator apparatus of are also convenient wherein said second stage attachment surface 184 is formed of a material selected from the group consisting of carbon fiber, steel, spring steel, fiberglass, plastic, stainless steel, and aluminum.
Further embodiments of such an actuator apparatus may comprise at least one dampener 150 attached to said compensator 103, 103′ and movably attached to at least one said actuating arm 114, said dampener 150 comprising a pliable stop 156 between said actuating arm 114 and said compensator 103, 103′.
Still further embodiments of such an actuator apparatus may comprise an outer frame 402, said outer frame 402 comprising an inner dampening stop 256 and an outer dampening stop 254 for each said actuating arm 114 wherein said outer dampening stop 254 is adapted to prevent said actuating arm 114 from overextending in the outward direction and said inner dampening stop 256 is adapted to prevent said actuating arm 114 from overextending in the inward direction.
Embodiments of such an actuator apparatus are also convenient wherein said first resilient strips 182′ are integral with said second stage attachment surface 184′, or wherein said second resilient strip ends 185 are attached to said second stage attachment surface 184.
Embodiments of such an actuator apparatus may also be used to form an actuated valve by further comprising a valve assembly 200 attached to said compensator 103, 103′, said valve assembly 200 comprising an inlet 208, an outlet 210, and a valve 212 in between said inlet 208 and said outlet 210, and a valve stem 204 operably connected to said valve 212 and to said second stage attachment surface 184, 184′ wherein movement of said second stage attachment surface 184, 184′ causes said valve stem 204 to operate said valve 212. In particular, such embodiments are convenient wherein said valve assembly 200 is an air valve.
Such actuator apparatuses may further comprise two dampeners 150 attached to said compensator 103, 103′ and movably attached to each said actuating arm 114, said dampeners comprising a two pliable stops 154, 156, one said pliable stop 156 being positioned between said actuating arms 114 and said compensator 103, 103′.
Embodiments of such an apparatus may also be convenient wherein said resilient strips 182, 182′ extend away from said second actuating arm ends 116 such that movement of said second actuating arm ends 116 toward said smart material device 102 urges said second stage attachment surface 184, 184′ away from said compensator 103, 103′. Alternative embodiments may be convenient wherein said resilient strips 182, 182′ extend toward said compensator 103, 103′ such that movement of said second actuating arm ends 116 toward said smart material device 102 urges said second stage attachment surface 184, 184′ toward said compensator 103, 103′.
For some applications, embodiments of such an apparatus may be convenient wherein said actuating arms 114 extend toward said compensator 103, 103′. For other applications, embodiments may be convenient wherein said actuating arms 114 extend away from said compensator 103, 103′.
Embodiments of such an apparatus are also convenient wherein (a) a central axis through the center of said smart material device 102 extends through the center of said first mounting surface 108; (b) an actuating arm axis extends through each said actuating arm's first actuating arm end 115 and said actuating arm's 114 second actuating arm end 116; and (c) said central axis and each said actuating arm axis are substantially parallel when said smart material device 102 is not activated.
Other embodiments are convenient wherein (a) a central axis through the center of said smart material device 102 extends through the center of said first mounting surface 108; (b) an actuating arm axis extends through each said actuating arm's 114 first actuating arm end 115 and second actuating arm end 116; and (c) the angle between said central axis and each said actuating arm axis is between zero and eighty-nine degrees, or between thirty and sixty degrees.
Additionally, certain embodiments in which thermal compensation and interchangeable parts are not required are convenient wherein said compensator 103′ is integral with said mechanical webs 113. Other embodiments in which thermal compensation and interchangeable parts are desirable are convenient wherein said compensator 103 is mechanically attached to said mechanical webs 113.
While the foregoing describes preferred embodiments of the actuator assembly and air valve assembly of the present invention, the present invention shall not be limited to those embodiments as many other embodiments will be readily apparent to those of ordinary skill in the art. It will also be understood by those of ordinary skill in the art, that while the embodiments described above and displayed in the figures demonstrate one set of applications for the present invention, the present invention is not limited to the specific applications described as high speed actuators of the present invention have many applications in various fields.

Claims

1. An actuator apparatus comprising a smart material device, a compensator, a movable supporting member, two mechanical webs, two actuating arms, and a second stage assembly wherein

(a) said mechanical webs comprise a first resilient member operably attached to said compensator and a second resilient member attached to said movable supporting member

(b) said movable supporting member comprises a first mounting surface,

(c) said smart material device is affixed between said first mounting surface and said compensator;

(d) said actuating arms comprise a first actuating arm end attached to one said mechanical web and an opposed second actuating arm end attached to said second stage assembly; and

(e) said second stage assembly comprises resilient strips having a first resilient strip end attached to said second actuating arm end and a second resilient strip end operably connected to a second stage attachment surface

wherein

application of an electrical potential causes said smart material device to expand, thereby urging said movable supporting member away from said compensator and causing said first and second resilient members to flex, thereby moving said actuating arms and causing said resilient strips to urge said second stage attachment surface in a direction substantially parallel to said smart material device.

2. The actuator apparatus of claim 1 wherein said resilient strips are formed of a material selected from the group consisting of steel, spring steel, carbon fiber, fiberglass, plastic, stainless steel, and aluminum.

3. The actuator apparatus of claim 1 wherein said second stage attachment surface is formed of a material selected from the group consisting of carbon fiber, steel, spring steel, fiberglass, plastic, stainless steel, and aluminum.

4. The actuator apparatus of claim 1 further comprising at least one dampener attached to said compensator and movably attached to at least one said actuating arm, said dampener comprising a pliable stop between said actuating arm and said compensator.

5. The actuator apparatus of claim 1 further comprising an outer frame, said outer frame comprising an inner dampening stop and an outer dampening stop for each said actuating arm wherein said outer dampening stop is adapted to prevent said actuating arm from overextending in the outward direction and said inner dampening stop is adapted to prevent said actuating arm from overextending in the inward direction.

6. The actuator apparatus of claim 1 wherein said resilient strips are integral with said second stage attachment surface.

7. The actuator apparatus of claim 1 wherein said second resilient strip ends are attached to said second stage attachment surface.

8. The actuator apparatus of claim 1 further comprising a valve assembly attached to said compensator, said valve assembly comprising an inlet, an outlet, and a valve in between said inlet and said outlet, and a valve stem operably connected to said valve and to said second stage attachment surface wherein movement of said second stage attachment surface causes said valve stem to operate said valve.

9. The actuator apparatus of claim 8 wherein said valve assembly is an air valve.

10. The actuator apparatus of claim 9 further comprising two dampeners attached to said compensator and movably attached to each said actuating arm, said dampeners comprising two pliable stops, one said pliable stop being positioned between said actuating arms and said compensator.

11. The actuator apparatus of claim 1 wherein said resilient strips extend away from said second actuating arm ends such that movement of said second actuating arm ends toward said smart material device urges said second stage attachment surface away from said compensator.

12. The actuator apparatus of claim 1 wherein said resilient strips extend toward said compensator such that movement of said second actuating arm ends toward said smart material device urges said second stage attachment surface toward said compensator.

13. The actuator apparatus of claim 1 wherein said actuating arms extend toward said compensator.

14. The actuator apparatus of claim 1 wherein said actuating arms extend away from said compensator.

15. The actuator apparatus of claim 1 wherein said compensator is integral with said mechanical webs.

16. The actuator apparatus of claim 1 wherein said compensator is mechanically attached to said mechanical webs.