WO2003008810A1

WO2003008810A1 - Booster actuator

Info

Publication number: WO2003008810A1
Application number: PCT/US2002/015904
Authority: WO
Inventors: James R. Gressel
Original assignee: Ansul Incorporated
Priority date: 2001-07-17
Filing date: 2002-05-20
Publication date: 2003-01-30
Also published as: CA2453576A1; HK1068388A1; CN1533481A; ZA200400291B; KR100908509B1; AU2002320034B2; US7021166B2; ATE435979T1; BR0211153B1; RU2285820C2; CN100374739C; US7444893B2; ES2328798T3; BR0211153A; US20040173768A1; RU2004104947A; EP1407149A1; US20030015049A1; KR20040017311A; US6722216B2

Abstract

A booster actuator (10) may be positioned between the solenoid (12) and a valve (14), and increases the energy output from the solenoid to activate the valve. The booster actuator (10) may include a force input member (28) and a force output member (30) each linearly movable with respect to a body (20) from an initial position to an activated position. A coil spring (46) biases the input member to the initial input position, while a plurality of disk springs (48) bias the output member (30) to the activated output position. A plurality of linking members (32) each pivotable with respect to the body normally retain the force output member in the initial position, but upon movement of the input member to the activated position release the force output member in response to the disk springs.

Description

BOOSTER ACTUATOR

Field of the Invention

The present invention relates to devices intended to be actuated by a low energy

input, and which output a high energy to the device to be actuated. More particularly, the

present invention relates to a booster actuator which uses mechanically stored energy to

move an actuator shaft with a force and stroke sufficient to actuate various types of devices.

Background of the Invention

Those involved in system designs have long required devices which provide a boost

or energy level increase to actuate a device. Electric energy input to a solenoid is directly

proportional to the output force, which practically limits the use of solenoids in conventional

low power electrical systems. A relatively small and inexpensive electrical solenoid may

send a signal which will stroke a solenoid plunger, although the force and/or the stroke of

the plunger in many cases is insufficient to activate the device intended. Accordingly,

boosters have been used between such low energy products, such as solenoids, and a device

to be activated to provide the desired energy level to actuate the intended device.

In the fire safety industry, various systems have been devised so that pressurized gas

may be released when a device is manually or automatically actuated. In some applications,

a booster or booster actuator may be positioned between a solenoid and a valve, with that

valve in turn being actuated to release agents, such as CO₂ or a mixture of nitrogen, argon,

and carbon dioxide, into the hazard area. Prior art booster actuators have used magnetized components to hold the actuator in

the set or armed position. Many of these actuators require an input force proportional to the

desired output force, or require additional electrical circuitry to return the actuator to the set

position.

Prior art actuators also include pressurized gas cartridges which are punctured, so that

the release of the pressurized gas in response to the puncture may be used to activate a

pneumatic device which releases the agent gas to the hazard area. Other types of actuators

utilize explosive components to generate the increased energy to activate a valve or

otherwise release the agent gas to the hazard area.

Many prior art boost devices have significant disadvantages which have limited their

use. Prior art boost devices are relatively complex and/or are not highly reliable, and other

devices cannot be easily reset. In still other booster devices, it is difficult to vary the force

which activates the boost device and/or to vary the output force from the boost device. The

disadvantages of the prior art are overcome by the present invention, and an improved

booster actuator is hereinafter disclosed.

Summary of the Invention

In a typical application, the booster actuator of the present invention may be located

between a solenoid and a valve. The actuator body houses a cam shaft or force input

member which is biased by a coil spring to the initial input position. The body also houses

an actuator shaft or force output member which is biased to the activated output position by

a plurality of disk springs. A plurality of circumferentially spaced links engage the force input member at one end and the force output member at the other end, and control of the

release of the force from the disk springs to the output member in response to movement of

the cam shaft. In another embodiment, an electrical coil is provided about the cam shaft, so

that a combination solenoid and booster is provided.

It is an object of the present invention to provide a booster apparatus with a force

input member and a force output member each movable relative to the actuator body, a

biasing member for biasing the force output member to the activated output position and at

least one linking member between the force input member and the force output member and

pivotably movable with respect to the body from the engaged position to a disengaged

position for releasing the force output member to the activated output position in response

to the biasing member. The linking member engages both the force input member and force

output member, and may cooperate with recesses in the input member and output member

for achieving the desired function.

It is another feature of the invention to provide a booster actuator with a force input

member, a low force biasing member for exerting a biasing force on the input member, a

force output member, another biasing member for exerting a high biasing force on the force

output member, and a linking member between the force input member and force output

member. Control of the actuator may be reliably obtained by providing two biasing

members each of which exert a force independent of the other biasing member on the input

member or output member.

It is a feature of the present invention to provide a booster actuator wherein the output

force from the actuator may be easily revised without redesigning the remainder of the actuator. Moreover, the change in the output force is independent of the energy required to

trigger activation of the booster, and the input energy required to trigger the actuator may be

separately selected without regard to the output requirements from the actuator.

It is another feature of the invention that the booster actuator is highly reliable, and

may be mechanically reset without the use of electrical devices. The reset may be

accomplished quickly and easily, and no replacement of parts is necessary.

It is a further feature of the invention to provide a booster actuator wherein a solenoid

coil is provided to control movement of the force input member relative to the actuator body.

It is an advantage of the present invention that the booster apparatus is highly reliable

and may be economically manufactured. The booster body preferably seals the internal

components from the environment.

These and further objects, features, and advantages of the present invention will

become apparent from the following detailed description, wherein reference is made to the

figures in the accompanying drawings.

Brief Description of the Drawings

Figure 1 is a simplified cross-sectional view of a booster actuator according to the

present invention positioned between an electrically activated solenoid and a valve which is

connected to a pressurized gas system.

Figure 2 is a cross-sectional view of a booster actuator generally shown in Figure 1.

An internal portion of the body has been removed for clarity of the illustrated components.

Figure 3 is a cross-sectional view of the body generally shown in Figure 2. Figure 4 is another cross-sectional view of the body, illustrating the spaced apart

guides for receiving each of the four linking members.

Figure 5 is a side view of a suitable booster reset device.

Figure 6 is a side view of a portion of an alternate embodiment, with an electrical coil surrounding the cam shaft.

Detailed Description of Preferred Embodiments

Referring to Figure 1 , the booster actuator 10 may be threadedly secured at one end

to the body of a solenoid 12 or another electrically actuated device, and may be similarly

connected at its opposed end to a valve 14, with the valve 14 intended to release gas to an

area in response to a sensed hazardous condition. The booster apparatus thus may be used

in conjunction with a relatively low energy electrical system which monitors the surrounding

environment, and outputs an electrical signal to actuate the solenoid 12 in response to the

sensed condition to release a selected gas, e.g., for extinguishing a fire. As shown in Figure

1, the solenoid 12 includes a plunger 13 which is movable relative to the body 20 of the

booster actuator 10. The actuator 10 receives this low energy input and outputs a high

energy to control plunger 15 of the valve 14, thereby activating the valve 14 to release the

compressed gas to the environment.

The actuator 10 as shown in Figure 2 includes a body 20 having a force receiving

input end 22 and a force delivery output end 24. Outer sleeve 25 may be provided for

engagement with conventional seals 26 to seal the interior of the body. The cam shaft or

force input member 28 is movable relative to the body from an initial input position as shown in Figure 2 to an activated output position in response to movement of the solenoid

plunger. The force output member 30 is similarly movable relative to the body from the

initial output position as shown in Figure 2 to an activated output position. Four links 32 are

equally spaced at 90° intervals about both the force input member and the force output

member, and are each pivotable about the pin 34 which is supported on the body 20. The

coil spring 46 biases the force input member to the initial input position, and a plurality of

disk springs, such as disk springs 48, bias the output member 30 to the activated output

position.

The force input member 28 is sealed with the body by a conventional O-ring 50, and

in the initial input position is biased by the coil spring 46 to engage shoulder 52 on the body.

Input member 28 includes an annular recess 54 for receiving the upper end of each of the

linking members 32 when in the disengaged position, thereby allowing release of the force

output member 30 normally held in the initial position by the lower end of each linking

member. As indicated in Figure 2, an upper roller 56 may be provided at the upper end of

each link 32, and a similar roller 58 may be provided at the lower end of each link. When

the actuator is in the initial position, each of the upper rollers thus engages the cylindrical

exterior surface 64 of the input member 28, while each lower roller 58 fits at least partially

within annular recess 66 in the force output member 30. Each roller is rotatably mounted on

a link with a respective pin 60 which is fixed to the link, and each link itself is pivotable

about pin 34 which is supported on the actuator body 20. The position of the input member

28 thus retains each of the four links in the position as shown in Figure 2, which in turn prevents downward movement of the force output member 30 in response to the disk springs

48.

A stop plate 62 has a central aperture therein sized to receive plunger 68 of the force

output device 30, with the stop plate being interconnected with the body by threads 70.

Conventional ports 72 may be provided in the stop plate for receiving a suitable tool to

thread the stop plate in place, with the final position of the stop plate resting against snap

ring 74. An 0-ring 76 is held in position within the stop plate by a combination back-up ring

and retaining ring 78, and provides sealing engagement between the plunger 68 and the stop

plate 62.

It is a particular feature of the invention that the force required to move the input

member 28 may be easily adjusted by varying the selection of the coil spring 46. The coil

spring is sized so that the booster actuator will not inadvertently activate in response to

vibration, jarring, and other forces commonly transmitted to a system. The selection of the

number of coils and the material for the coils for the spring 46 are independent, however, of

the selection of the biasing member 48, which preferably is a plurality of disk springs. The

number of disk springs and the orientation of these springs with respect to each other affect

the force and the stroke which will move the force output member to the activated position,

thereby extending the plunger from the stop plate and, in an exemplary application, actuating

the valve as shown in Figure 1. For this exemplary embodiment, it should be understood that

the force output member may move from the initial position as shown in Figure 2 to a

position wherein the surface 81 engages the snap ring 74. This movement of the force output

member 30 to the activated output position thus results when each of the rollers 58 moves out of engagement with the recess 66, so that each of the rollers 58 rolls out of the recess and

into engagement with the cylindrical surface 67 on force output member 30. At the same

time, upper rollers 56 roll out of engagement with the cylindrical surface 64 in the force

input member and roll partially at least within the annular recess 54 sized to receive these

rollers. This action thus causes pivoting of the links 32 to release the force output member

to the activated position.

Figure 3 shows in greater detail the construction of a suitable actuator body 20, and

particularly the cavity 80 for receiving the disk springs 48. The uppermost disk spring as

shown in Figure 2 thus rests against the surface 82 as shown in Figure 3. Figures 3 and 4

also depict four pairs of circumferentially spaced guide plates 86 and 88, thereby providing

a slot 90 therebetween for receiving a suitable link 32. Figure 4 also depicts the aligned

throughports 92 in each pair of guide plates for receiving a suitable link pin 34. The lower

flange 94 of the body 20 may have a suitable exterior configuration, such as a hex

configuration, for engagement with a conventional tool to facilitate threadably connecting

the body 20 to a solenoid.

It is a feature of the invention that the interior of the body 20 and thus each of the

movable components within the body is sealed from the surrounding environment, with this

objective being accomplished by the conventional seals 26 which seal between sleeve 25 and

the body, and by the seals 50 and 76 which seal with the force input member and the force

output member, respectively. A sufficient seal may be created between the body 20 and the

stop plate 62 due to interference of the threads although, if desired, another O-ring seal could

be provided for sealing between the stop plate and the body. In preferred embodiments, at least three linking members are circumferentially

arranged about the force input member and the force output member. Three linking members

at 120° interval spacing provide high reliability by distributing the applied forces equally

about the input member and the output member. A preferred embodiment as shown in the

figures utilizes four linking members spaced at 90° intervals. The rollers 56 and 58

provided at the end of the linking members reduce frictional forces when the linking

members are moved from an engaged position as shown in Figure 2 for retaining the force

output member 30 in the initial output position to a disengaged position which releases the

force output member to the activated output position. In alternate embodiments, the rollers

may be eliminated, or may be replaced with other conventional members intended to reduce

friction with the force input and force output members.

Coil spring 46 acts between the force output member 30 and the force input member

28. The force of this spring may be easily altered without modifying other components of

the booster actuator in order to change the force required to activate the booster 10.

Similarly, the size, orientation, and number of disk springs 48 may be altered to effect the

stroke length and/or the force which will be output by the plunger 68 when moved to the

activated output position. Alternative types of springs or other biasing members may be

utilized.

The booster actuator of the present invention provides a mechanical separation of the

input member and the output member. The coil spring 46 biases the input member to the

initial position, but this exerts a small force on the output member compared to the bias of

the springs 48. By providing no direct mechanical connection between the input member and the output member, the reactive forces on the valve which are transmitted back to the

force output member during actuation of the booster are prevented from being transmitted

to the force input member and then to the solenoid. The coil spring thus isolates the reactive

force on the output member from the forces applied to the input member, and a latching

solenoid mechamsm may thus be used to activate the booster without fear of damage from

these reactive forces.

Once the booster is activated, the booster may be easily reset without use of electrical

devices, and without replacement of parts. After the valve 14 has been removed from the

booster body, reset device 94 as shown in Figure 5 may be connected to the threads 70 on

the body. After the reset outer body 96 bottoms out against the stop plate 62, the bolt 98

may be rotated relative to outer body 96 to project the tip 97 toward the stop plate 62. The

tip 97 is thereby forced into engagement with the end of the plunger 68, thereby forcing the

force output member 30 back to the initial position as shown in Figure 2. The return of the

force output member to the initial position also increases the force on the coil spring to return

the force input member to the initial position.

Figure 6 depicts another embodiment of the invention, wherein a combination

solenoid and booster actuator is provided. That portion of the booster 10 to the right of the

force input member 128 may be as described above. In this embodiment, however, an

extension of the force input member is provided so that the extended length force input

member 128 is positioned within a solenoid coil 114. The solenoid coil may also be referred

to as a magnetic latch subassembly, which receives electrical power to selectively move the

input member 128. Those skilled in the art will appreciate that an extended length force input member may be used, as shown, or a two-piece or multi-piece mechanical

interconnection made between the solenoid plunger and the force input member. Activation

of the coil 114 thus initiates movement of the solenoid plunger, which in this case is the

force input member 128. Force input member 128 includes a stop 130 for engagement with

the surface 132 to limit the travel of the force input member. Figure 6 depicts sleeve 134

enclosing the solenoid 114, and body 136 which connects sleeve 134 with sleeve 25.

While a preferred embodiment of the present invention has been illustrated in detail,

it is apparent that modifications and adaptations of the proposed embodiment will occur to

those skilled in the art. However, it is to be expressly understood that such modifications

and adaptations are within the spirit and scope of the present invention as set forth in the

following claims.

Claims

What is claimed is:

1. A booster actuator for receiving a low energy input and outputting a high

energy output to operate a device, the booster comprising:

a body having a force receiving input end and force delivery output end;

a force input member movable relative to the body in response to the low energy

force input from an initial input position to an activated input position;

a force output member movable relative to the body in response to movement of the

force input member from an initial output position to an activated output position;

a biasing member for biasing the force output member to the activated output

position; and

a linking member between the force input member and the force output member and

pivotally movable with respect to the body from an engaged position for retaining the force

output member in the initial output position to a disengaged position for releasing the force

output member to the activated output position, the linking member having an input end

engaging the force input member and an output end engaging the force output member.

2. The booster actuator as defined in Claim 1 , further comprising:

another biasing member for biasing the force input member to the initial input

position.

3. The booster actuator as defined in Claim 1 , wherein the force output member includes an output member recess for receiving a lower end of the linking member when in

the engaged position.

4. The booster actuator as defined in Claim 3, wherein the force input member

includes an input member recess for receiving an upper end of the linking member when in

the disengaged position, thereby allowing disengagement of the lower end of the linking

member from the output member recess.

5. The booster actuator as defined in Claim 1, wherein at least three linking

members each pivotable with respect to the body are circumferentially arranged about the force input member and the force output member.

6. The booster actuator as defined in Claim 5, wherein four linking members are

spaced circumferentially at approximately 90° intervals about the force input member and

force output member.

7. The booster actuator as defined in Claim 1, further comprising:

the biasing member comprises a plurality of disk springs; and

another biasing member for biasing the force input member to the initial input

position.

8. The booster actuator as defined in Claim 1 , further comprising:

an electrical coil surrounding the force input member, such that a change in electrical

energy to the coil moves the force input member to the activated input position.

9. The booster actuator as defined in Claim 1 , wherein each of the input end and

output end of the linking member is provided with a roller for engaging the force input

member and the force output member, respectively.

10. The booster actuator as defined in Claim 1 , wherein the force delivery output

end of the body includes threads, and a reset member threaded to the delivery output end is

rotated relative to the body to forceably engage the force output member to move the force

output member from the activated position to the initial position.

11. A booster actuator for receiving a low energy force and outputting a high

energy force output to operate another device, the booster comprising:

a body having a force receiving input end and force delivery output end;

a force input member linearly movable relative to the body in response to the low

energy force input from an initial input position to an activated input position;

a first biasing member for biasing the force input member to the initial input position;

a force output member linearly movable relative to the body in response to movement

of the force input member from an initial output position to an activated output position; a second biasing member for biasing the force output member to the activated output

position; and

a linking member between the force input member and the force output member and

movable from an engaged position for retaining the force output member in the initial output

position to a disengaged position for releasing the force output member to the activated

output position.

12. The booster actuator as defined in Claim 11, wherein at least three linking

members each pivotable with respect to the body are circumferentially arranged about the

force input member and the force output member.

13. The booster actuator as defined in Claim 11 , wherein the first biasing

member is a coil spring, and the second biasing member comprises a plurality of disk

springs.

14. The booster actuator as defined in Claim 11 , further comprising:

15. The booster actuator as defined in Claim 11, wherein each of the input end and output end of the linking member is provided with a roller for engaging the force input

member and force output member, respectively.

16. A booster actuator for receiving a low energy input from an electrically

activated device and outputting a high energy to activate a release of pressurized gas to a

hazard area, the booster comprising:

a body having a force receiving input end and force delivery output end;

of the force input member from an initial output position to an activated output position;

a first biasing member for biasing the force output member to the activated output position;

a second biasing member for biasing the output force member to the activated output

position;

a plurality of linking members each between the force input member and the force

output member and pivotally movable relative to the body from an engaged position for

retaining the force output member in the initial output position to a disengaged position for

releasing the force output member to the activated output position, the linking members

being circumferentially arranged about the force input member and the force output member and each having an input end engaging the force input member and an output end engaging

the force output member; and

the force output member includes an output member recess for receiving a lower end

of each of the linking members when in the engaged position.

17. The booster actuator as defined in Claim 16, wherein the force input member

member from the output member recess.

18. The booster actuator as defined in Claim 16, wherein a central axis of the

force input member is substantially aligned with a central axis of the force output member.

19. The booster actuator as defined in Claim 16, further comprising:

the second biasing member comprises a plurality of disk springs.

20. The booster actuator as defined in Claim 16, wherein the force delivery

output end of the body includes threads, and a reset member threaded to the delivery output

end is rotated relative to the body to engage the force output member to move the force

output member from the activated position to the initial position.