Seal check device

Abstract

To provide a seal check device structurally effective for performing a seal check procedure.SOLUTION: A seal check device 100 includes a valve seat 110 having an opening 113, and a lever assembly arranged in proximity to the opening 113 on a rear side of the valve seat 110, the lever assembly including a lever having a first end coupled to a valve member configured to close the opening 113 and a second end accessible for contact from a front side of the valve seat 110, the lever supported on and movable about a pivot, movement of the lever about the pivot causing the valve member to move toward the valve seat 110 or away from the valve seat 110, the lever operable to apply the force on the second end of the lever from the front side of the valve seat 110 to actuate the valve member toward the opening 113 and maintain closure of the opening 113.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to respiratory protection devices, and more particularly to respiratory protection devices including sealcheck devices. [Background technology]

[0002] Respiratory protective devices ensure that clean air is available to the wearer by forcing air from the external environment through a filter media before being inhaled by the wearer. The effectiveness of filtration depends on maintaining a good seal between the respirator and the wearer's face. The best possible filtration is achieved when all inhaled air is drawn through the filter media. On the other hand, if air from the external environment enters the respirator through gaps in the respirator or gaps between the respirator and the wearer's face due to poor fit, unfiltered air is inhaled by the wearer, thereby reducing the effectiveness of the respirator.

[0003] Various seal check devices have been proposed to test the integrity of the seal provided by a respiratory protective device. In a respirator equipped with a positive-pressure seal check device, the wearer exhales into the respirator while the exhalation valve of the respirator is blocked. If no leak is present, air within the respirator cannot escape through the exhalation valve, resulting in a perceived increase in internal pressure within the respirator. In a respirator equipped with a negative-pressure seal check device, the wearer manually blocks a filter cartridge connected to the respirator while inhaling, preventing air from entering the respirator. This reduces the internal pressure within the respirator, resulting in a perceived vacuum. In either case, if a leak is present, the pressure change is not apparent, drawing the wearer's attention to a possible defect or malfunction in the respirator's seal around the wearer's face. Both methods typically rely on structural additions to the respirator, requiring the wearer to manually close the air inlet or outlet to completely seal the respirator during the seal check procedure. Such structural additions may include components attached to either side of the respirator and may extend across the respirator through vias drilled into the respirator frame, although such configurations have the disadvantage of compromising the respirator seal.

[0004] It would be desirable to provide a seal check device that resides entirely within the respirator and is structurally effective for performing seal check procedures on the respirator without requiring drilled holes through the body of the respirator for mounting purposes or removable components. Summary of the Invention

[0005] The present invention provides a seal check device that includes a valve seat having an opening, and a lever assembly arranged adjacent to the opening on the rear side of the valve seat. The lever assembly includes a lever having a first end coupled to a valve member configured to close the opening and a second end accessible for contact from the front side of the valve seat. The lever is supported on a pivot and is movable about the pivot, such that movement of the lever about the pivot moves the valve member toward or away from the valve seat, and the lever is operable to actuate the valve member toward the opening and maintain closure of the opening by applying a force on the second end of the lever from the front side of the valve seat.

[0006] The present invention further provides a respirator including a facepiece and a seal check device disposed on an interior surface of the facepiece. The seal check device includes a valve seat having an opening, and a lever assembly disposed adjacent the opening on the rear side of the valve seat. The lever assembly includes a lever having a first end coupled to a valve member configured to close the opening and a second end accessible for contact from the front side of the valve seat. The lever is supported on a pivot and is movable about the pivot, such that movement of the lever about the pivot moves the valve member toward or away from the valve seat, and the lever is operable to actuate the valve member toward the opening and maintain closure of the opening by applying a force on the second end of the lever from the front side of the valve seat.

[0007] The present invention differs from known seal check devices in that it employs a lever assembly to actuate the valve member for the seal check procedure. The mechanical advantage of a lever mechanism allows the valve member to be actuated with reduced force or to move over a longer distance, as opposed to mechanisms that apply direct force on the sealing component. Examples of first-class levers include a seesaw and a pair of pliers. The lever assembly also helps align the sealing component with the opening so that it is sealed with high accuracy and reliability. Furthermore, the lever assembly helps reduce the sequential stacking of components across the thickness of the respirator, thereby reducing the thickness of the seal check device by instead aligning some components, such as the lever, further to the side of the opening. The lever assembly also moves away from in-cartridge seal check designs, where the user must press the cartridge for the seal check procedure, which can artificially improve the respirator seal when the user presses the cartridge and respirator against their face and unintentionally hide defects in the respirator during the seal check procedure.

[0008] Because a seal check device is arranged on the inside of a respirator, a technical problem that arises is how a user can activate a lever assembly present within the respirator. The present invention solves this problem by arranging the lever end accessible for contact from the front side of the seal check device, making the lever assembly easily operable underneath the respirator. For example, the lever end can be arranged below a designated button position on the respirator, so that the wearer simply presses the respirator at the button position to activate the lever underneath the respirator. The lever assembly does not need to extend through the respirator for access, and therefore does not need to form an access hole into the respirator. As mentioned above, some known seal check devices require components to be arranged on both the inside and outside of the respirator as structures that extend across the respirator through a drilled hole in order for these structures to be attached to or slidably arranged on the respirator. The presence of such holes can cause air leaks and lead to undesirable false positives during a seal check. By arranging the seal check device entirely on the inside of the respirator, it is possible to avoid components that require holes to be formed on the face piece. The seal check device can be attached to the respirator via a connection feature that connects to the portion of the outer cover where the inhalation or exhalation port is the only structure extending through the face seal. Furthermore, known seal check devices are sometimes designed to have a high degree of structural integrity with the respirator body and cannot be easily removed for cleaning or replacement. In contrast, in the present invention, the seal check device is designed to be modular and can be easily removed and replaced without affecting the function of the respirator.

[0009] These and other advantages of the present invention will be more fully described and illustrated in the detailed description of the invention and the drawings, in which like reference numerals are used to refer to like parts. It should be understood, however, that the drawings and description are for illustrative purposes only and should not be construed in a manner that will unduly limit the scope of the invention.

[0010] Glossary

[0011] The terms set forth below have the meanings defined below.

[0012] "forward side of the valve seat" refers to any location forward of the forward surface of the valve seat, including a side forward location, a top forward location, and a bottom forward location, the front surface of the valve seat being the surface that faces away from the wearer when the valve seat is installed on the respirator;

[0013] "Lever" means any structure supported on and movable about a pivot;

[0014] "lever assembly" means a structure of one or more parts assembled together, including a lever supported on and movable about a pivot;

[0015] "Pivot" means the point or axis about which a lever rotates or pivots. The term "pivot" is used in the singular to refer to both single pivot and multiple pivot embodiments of two, three or more pivots;

[0016] "Primary opening" means an opening formed on the body of a valve seat;

[0017] "Proximity" means close physical proximity or close proximity;

[0018] "rear side of the valve seat" refers to any position rearward of the rear surface of the valve seat, including a side rear position, an upper rear position, and a lower rear position, the rear surface of the valve seat being the surface facing the wearer when the valve seat is installed on the respirator;

[0019] "Respirator" means a device worn by a person over at least the respiratory passages (nose and mouth) to provide the person with a supply of clean air for breathing;

[0020] "Seal check" means a procedure used to evaluate the overall quality of the pneumatic seal between a respirator and a wearer's face. The terms "fit check" or "fit checker," as sometimes referred to in the industry, refer to a procedure or device used to evaluate the fit of a respirator to a wearer's face. As used herein, the term "seal check" includes not only the factors evaluated in a fit check procedure, but also all other factors that affect the pneumatic seal of the respirator, such as attachment holes through the face portion of the respirator, voids between components, and cracks or tears in components that could cause air leaks. Correspondingly, a "fit check," as referred to in the industry, evaluates face fit but does not necessarily provide a more extensive evaluation as contemplated in the "seal check" procedure defined herein.

[0021] "seal check device" means a device used in conjunction with a respirator to allow the wearer to perform a seal check on the respirator;

[0022] "Secondary opening" means an opening formed on the rear cover of the valve seat (if present);

[0023] "valve" means a device for controlling the flow of air through an opening by covering the opening or by keeping the opening uncovered;

[0024] "Valve member" means a structure for closing an opening on a valve seat;

[0025] "Valve seat" means a structure having a primary opening through which air flows and which is controlled by a valve.

[0026] Exemplary embodiments are described in more detail in the figures and detailed description that follow. [Brief explanation of the drawings]

[0027] The present disclosure may be further described with reference to the accompanying drawings, in which like structure is designated by like reference numerals throughout the various drawings. [Figure 1] FIG. 1 is a front perspective view of a seal checking device according to a first embodiment. [Figure 2] FIG. 1 is a rear perspective view of a seal checking device according to a first embodiment. [Figure 3] FIG. 1 is a side plan view of a seal checking device according to a first embodiment. [Figure 4] FIG. 2 is a rear plan view of the lever assembly according to the first embodiment. [Figure 5] FIG. 2 is a perspective view of the valve seat according to the first embodiment. [Figure 6] FIG. 1 is a perspective view of the components of a three-component lever assembly. [Figure 7] FIG. 10 is a side view of a seal checking device according to a second embodiment. [Figure 8] FIG. 10 is a rear perspective view of a seal checking device according to a third embodiment. [Figure 9] FIG. 11 is a rear perspective view of the lever assembly according to the third embodiment. [Figure 10] FIG. 10 is a rear perspective view of a seal checking device according to a fourth embodiment. [Figure 11] FIG. 10 is a rear perspective view of the lever assembly according to the fourth embodiment. [Figure 12] 1 is a front perspective view of a seal checking device having a deflection element according to a first embodiment; FIG. [Figure 13] FIG. 10 is a rear perspective view of a modular seal checking device according to a fifth embodiment. [Figure 14] FIG. 1 is a rear perspective view of a respirator with an integrated seal check device. [Figure 15] FIG. 10 is a rear perspective view of the front cover of the ventilator. DETAILED DESCRIPTION OF THE INVENTION

[0028] In describing preferred embodiments of the present invention, specific terminology is used for the sake of clarity. However, it should be understood that the present invention is not limited to the specific terminology so selected, and each term so selected includes all technical equivalents that operate in a similar manner. The seal check device as described in the following embodiments is not limited to use in any particular type of seal check procedure, but can be used to seal the respiratory air inlet or outlet. The embodiments described herein, in connection with negative or positive pressure seal check procedures, are merely exemplary in nature.

[0029] Figures 1-3 illustrate a seal check device 100 that can be used with reusable respirators that can utilize a single or dual filter cartridge. Examples of single and dual filter cartridge respirators are described in U.S. Patents U.S. Pat. Nos. 7,320,722, 7,650,884, 9,517,367, 9,393,448, and 11,305,134. Figure 1 illustrates the seal check device 100, which includes a valve seat 110 having an opening 113 for airflow defined thereon and extending therethrough. A forward side 116 of the valve seat is configured to be installed toward the interior of the respirator. For example, raised walls 119, 121 surrounding the openings 113, 123 can be designed to be secured to corresponding structures on the interior of the respirator, such as a silicone face seal or a molded plastic face piece. The valve seat 110 is configured to be a long structure, optionally 1.5, 2, 3 or more times its width dimension, to accommodate the two openings, depending on the shape of the raised walls 119, 121 around the openings, which may be circular, oval, or square in shape. The valve seat 110 is preferably a molded structure comprising a durable, high-strength polymeric material with a complex configuration.

[0030] FIG. 2 illustrates the rearward side 125 of the valve seat 110, on which a lever assembly 130 is disposed adjacent the opening 113. A first end 133 of the lever assembly 130 is attached to a valve member 140 by a linkage 149 mounted through a slot formed in the lateral sidewall 128 of the valve seat. Actuation of the lever assembly 130 moves the valve member 140 from the rearward side of the valve seat toward or away from the valve 117 disposed over the opening 113 (FIG. 1). When the wearer performs a seal check procedure, the wearer manually applies a force on the second end 136 of the lever assembly from the front side of the respirator. The lever assembly is configured so that this force acts in an inward direction, moving toward the wearer of the respirator. In doing so, the first end of the lever assembly is pivoted in the opposite direction, moving outward, away from the wearer, causing the valve member to move toward the valve 117 and seal against the opening. In order for the second end 136 of the lever assembly to be operable even though the seal check device is located on the inside surface of the respirator, the second end 136 of the lever assembly is positioned accessible for contact from the front side of the valve seat despite being underneath the respirator, which means that in one embodiment the second end of the lever assembly is configured to extend longitudinally beyond the edge of the valve seat so as to be accessible for contact by a wearer attempting to depress the lever from the front side of the valve seat and the respirator.

[0031] FIG. 3 illustrates the direction of force applied to the second end 136 of the lever assembly 130 (illustrated by arrow 150) and the direction of movement of the first end 133 of the lever assembly 130 and the associated valve member (illustrated by arrow 153). A force applied on the second end of the lever acts in a direction that moves the lever from the forward side of the valve seat toward the lever. From the wearer's perspective, a force applied on the lever acts in a direction that moves the valve member 140 toward the wearer. Such a force actuates the valve member 140 to move in the opposite direction, outward, away from the wearer of the respirator. In this embodiment, a pivot portion 177 of the lever assembly is located between the first end 133 and the second end 136 of the lever assembly 130. The pivot portion may include a hinge joint 177 formed between the lever assembly and the valve seat or a pivot contact point 137 between the lever assembly and the raised sidewall 128. A slot 129 provided in the lateral sidewall 128 allows a first end 133 of the lever to be coupled to the valve member. The slot 129 is shown oriented horizontally in the drawings. The slot 129 may be configured to slope downward at the rear such that the lever end 133 rests against the lower end of the slot 129 due to gravity, thereby maintaining the lever assembly in a default open position.

[0032] The embodiment illustrated in FIG. 2 illustrates the valve member 140 as a valve cover 141 for pressing against the valve 117. The valve cover 141 is disposed in the opening 113 behind the valve seat 110. The valve 117 can be pressurized by the valve cover 141 against a valve support 146 located within the opening. The valve 117 allows air to flow in one direction through the opening and blocks air from flowing in the opposite direction, and can include any suitable valve used in respirators, such as a flexible flap-type diaphragm valve centrally attached to the valve support 146. The valve cover can have any shape as long as it effectively presses against the valve 117 to prevent the valve from opening when a seal check procedure is performed. For example, the valve cover can include a circular frame, as illustrated in FIG. 2, to match the outer shape of a circular diaphragm valve in the opening of the valve seat. Alternatively, the valve cover can include an oval, square, or rectangular shape. 4, the valve cover includes a circular frame 160 having spokes 163 connected to a central hub 166 similar to the spokes on a bicycle wheel. The second end 136 of the lever assembly 130 can include a contact area that can be pressed against the front side of the valve seat to actuate the valve member 140 toward the opening.

[0033] The lever assembly can include a lever having an arched shape, with a first end of the lever including a pair of bifurcated arms and a second end including a contact area for actuating the lever. Referring to FIG. 4 , at the first end of lever 170, bifurcated arms 172 extend toward the side of the valve seat, each arm having an opening for receiving a support shaft 178 extending outward from the valve cover 160 to mount the valve cover 160 onto the lever arm. At the second end of the lever, a push tap 174 is provided around the middle of the lever where the bifurcated arms meet, providing a contact area for actuating the lever. Each of the lever arms forms a connection with the valve member, enabling the lever to actuate the valve member. In one embodiment, a hub-to-shaft connection is provided. Other connection types, such as a ball joint connection, may also be used. In a preferred embodiment, the connection is releasable to release the valve cover from the lever. This facilitates disassembly of the lever assembly or the seal check device for cleaning or replacing worn valve components.

[0034] A lever is supported on a pivot and can move about the pivot. Such movement is typically described as a see-saw or rocking motion. In a lever system, the position of the pivot determines the mechanical magnification and direction of the applied force. Generally, the position of the pivot relative to the input and output forces determines the type. In a first-class lever, the pivot is located between the applied force and the load. In a second-class lever, the pivot is at one end, with the input force applied to the other end and the output force applied to the pivot. In a third-class lever, the pivot is at one end, with the input force applied to the pivot and the output force applied to the other end. The operating principle of a first-class lever can be advantageously employed in embodiments to amplify forces or increase the distance a load travels. In one embodiment, the pivot includes a hinge-type connection. In FIG. 4, a pair of hinges 177 are arranged between the first and second ends of the lever. The location of the hinges between the load, i.e., the valve cover, and the application force, i.e., the contact area 174 where the force is applied, makes the lever a first-class lever, with the fulcrum located between the application force and the resistance force. To improve mechanical leverage, the fulcrum is preferably located closer to the load, i.e., closer to the first end 133. In other words, the distance between the first end of the lever assembly and the fulcrum is preferably shorter than the distance between the second end of the lever assembly and the fulcrum. The hinges 177 can be attached to the support frame or the valve seat.

[0035] FIG. 5 illustrates a valve seat 100 without a lever assembly. The valve seat has an elongated structure with a first opening 113 having a valve support 146 disposed therein. The first opening 113 serves as an opening for inhaled air to enter the valve seat. The valve seat 100 also has a second opening 123 having a support 156 disposed therein. The second opening 123 serves as an opening for exhaled air to exit the valve seat. A lever assembly can be disposed over the first opening 113 or the second opening 123 to close the opening for inhaled air, thereby providing a seal check device for a negative pressure seal check, or to close the opening for exhaled air, thereby providing a seal check device for a positive pressure seal check.

[0036] FIG. 6 illustrates one embodiment of a lever assembly 190 having three components: a support frame 180, a lever 181, and a valve cover 182. Both the support frame 180 and the lever 181 are similarly arched in shape. The support frame 180 includes a bifurcated guide arm 180A and a recess 180B for mounting the hinge 181A of the lever 181. A pair of slots 180C are defined on the support frame 180 to accommodate the respective connections between the pair of bifurcated guide arms 180A of the lever and the valve cover 182. The slots 180C define tracks along which the respective connections are allowed to move when the lever is actuated. After these three components—the lever, support frame, and valve cover—are assembled together, they can be secured onto a valve seat. The valve cover 182 has a pair of support shafts 182A that are received within the slots 180C and hubs 181B and are arranged to form a shaft-hub connection. In the embodiment illustrated by Figures 1-3, the support frame of Figure 6 is formed integrally with the valve seat, eliminating the need for a separate support frame. The support frame is formed as a raised wall 128 that at least partially surrounds the opening. A pair of slots can be formed on the raised wall to accommodate the respective connections between the pair of bifurcated arms and the valve cover, the slots defining tracks along which the respective connections are allowed to move when the lever is actuated, similar to those seen from the support frame described in Figure 6.

[0037] Generally, the lever assembly is movable in a plane that is not parallel to the plane of the opening. In other words, the movement of the lever assembly is located in any plane that intersects the plane of the opening 113, as illustrated by dotted line 158 in FIG. 3 . In a preferred embodiment, the lever assembly is movable toward or away from the opening in a back-and-forth manner, with the movement of the valve member being perpendicular to the plane of the opening 113. This means that the angle of incidence between the plane of the opening 113 and the plane of the lever assembly movement is 90°, as illustrated by dotted line 158. Alternatively, the plane of the lever assembly movement can also be tilted relative to the plane of the opening, and can be set at an angle of incidence of 80°, 70°, or 60° or less with the plane of the opening.

[0038] In another embodiment, the valve member includes a valve cover configured to actuate toward and cover the opening without contacting the diaphragm valve. Referring to FIG. 7, the valve cover 140 is configured as a continuous plate or cup having a forward-projecting lip 169 around the periphery of the valve cover so that when the lever assembly is actuated during a seal check procedure, the lip 169 of the valve cover 140 contacts and seals with the valve seat around the opening 113 and around the circumference of the valve 117 without directly contacting the valve 117. In this embodiment, constant contact with the valve 117, which may be made of a soft material, is avoided, thereby reducing wear and tear caused by repeated seal checks.

[0039] In certain embodiments, the lever assembly is directly connected to the valve seat by a hinge. FIG. 8 illustrates a seal check device 200 including a lever assembly, where the lever assembly 210 includes a lever having a hinge connection 213 formed directly with the valve seat. This allows the wearer to perform a seal check procedure by applying pressure to the second end 250 of the lever, actuating the valve cover toward the valve and closing the opening. FIG. 9 illustrates the lever assembly in more detail. In this embodiment, the lever assembly 210 includes a pair of bifurcated arms 220 that connect to the valve cover 240 from the inside, for example, via a shaft-hub connection. In this case, a shaft 223 extends from the bifurcated arms 220, and a corresponding hub 243 that receives the shaft 223 is formed on the valve cover 240. Advantageously, this allows the lever arms to be pinched together to release the arms from the valve cover 240 when repair or replacement is required for the valve or the lever or any other component below the lever.

[0040] When designed as a negative pressure seal checker, the valve is arranged at the inhalation opening. It is contemplated that the device, along with other modifications, can also operate as a positive pressure seal checker with the valve arranged at the exhalation opening.

[0041] While the above embodiments illustrate a lever mechanism that actuates the valve member in an outward direction, away from the wearer, it is possible to implement a lever mechanism in which the valve member moves inward toward the wearer when actuated. The direction of valve member actuation can change the force required to actuate the lever assembly during a seal check procedure. In the case of a negative pressure seal check device installed at the intake opening, i.e., by moving the valve member toward the wearer, the advantage of reversing the valve member actuation direction is that the intake suction force serves to pull the valve at the intake opening closed. Such suction force exerts a complementary force on the valve member, reducing the corresponding force required to actuate the lever.

[0042] FIG. 10 illustrates one embodiment of the present invention in which the seal check device 300 includes a lever assembly that actuates the valve member in an inward direction, i.e., toward the wearer. The lever assembly 320 includes a first lever arm 325 having a first end that connects to the valve member 327 and an opposite end A that pivots on a first hinge. The lever assembly further includes a second lever arm 322 having a second end accessible for application of pressure by a user from the front side of the valve seat. The second lever arm has an opposite end B that pivots on a second hinge, with ends A and B meshing with each other through a gear-tooth meshing. In this manner, force applied to the second lever arm 322 is converted into force that actuates the first lever arm 325, which ultimately actuates the valve member. The first lever arm 325 is bifurcated and connected to the valve member 327 via a central holder 329. A first end of the first lever arm extends into an opening 370 in the rear cover 360 and couples with the valve member 327 .

[0043] To explain the embodiment of FIG. 10 in more detail, FIG. 11 illustrates that second lever arm 322 pivots on second hinge 343, while first lever arm 325 pivots on first hinge 353. Both hinges 343, 353 directly connect the levers to the valve seat. Second lever arm 322 includes ends A1 and A2, where end A1 is accessible for actuation by the wearer, and first lever arm 325 includes ends B1 and B2, where end B1 connects to the valve member. Ends A2 and B2 of the second and first lever arms mesh together via a counter-rotating gear-tooth connection, such that pivotal movement of second lever arm 322 is converted into a force that induces pivotal movement of first lever arm 325 in the opposite direction. This allows the first lever arm 325 to actuate the valve member 327 in an inward direction toward the rear cover 360, which defines the secondary opening 370. The primary opening 113 (FIG. 1) is located in the body of the valve seat, opposite the secondary opening. The valve member 327 is disposed between the primary opening 113 and the secondary opening 370 (FIG. 10). The rear cover 360 (FIG. 10) forms an openable enclosure for enclosing the valve member 327 together with the valve seat 310 (FIG. 10), where the secondary opening 370 of the valve seat is defined by the rear cover. Thus, the secondary opening 370 is a passageway through which air flow occurs, and the seal check procedure is performed by sealing the secondary opening 370 with a seal check device instead of sealing the primary opening 113 (FIG. 1). The releasable rear cover 360 encloses the valve member and can be opened to replace the valve member. In this embodiment, the valve member includes a flexible diaphragm valve arranged on the inside of the rear cover 360 (FIG. 10) at the secondary opening 370, and configured such that when the lever is actuated, the flexible diaphragm valve acts toward the opening in the rear cover, covering the opening and preventing air from flowing into the opening from the forward side of the valve seat.

[0044] To prevent the lever assembly from unintentionally blocking the valve seat opening and affecting the wearer's breathing, it is preferable to implement a safety mechanism that maintains the lever assembly in an open position by default. Such a feature is optional and not necessary if the lever assembly is modified to maintain the open position. Accordingly, in one embodiment, the device further includes a biasing member arranged to bias the valve member away from the opening by default. In FIG. 12 , device 400 includes a lever assembly 410 that is engaged by a biasing member including a leaf spring 420. At rest, leaf spring 420 abuts the bifurcated arms of the lever, maintaining the bifurcated arms in a position where the valve member (not shown) is spaced apart from the opening 430. When the lever is actuated by the wearer to close the opening in the valve seat to perform a seal check, a force is applied on the lever assembly, compressing the leaf spring while actuating the valve member toward the opening, and then maintaining the valve member in its original position to maintain closure of the opening as the seal check procedure is performed by the wearer. Once the wearer has completed the seal check procedure, the lever is released, causing the tension in the leaf spring to push the lever assembly back to its default position, keeping the valve member separated from the opening in the valve seat and allowing air to flow through the opening in the valve seat. Any suitable biasing device can be employed in place of the leaf spring. In different embodiments, the biasing member can include a central compression spring that biases the valve member away from the opening.

[0045] Another aspect of the invention relates to a respirator including a seal check device, the respirator including a face piece and a seal check device disposed on an inner surface of the face piece, the seal check device including a valve seat having an opening, and a lever assembly disposed proximate the opening rearward of the valve seat, the lever assembly including a lever having a first end coupled to a valve member configured to close the opening and a second end accessible for contact from a front side of the valve seat, the lever supported on a pivot portion and movable about the pivot portion, movement of the lever about the pivot portion moves the valve member toward or away from the valve seat, and the lever is operable to actuate the valve member toward the opening and maintain closure of the opening by applying a force on the second end of the lever from the front side of the valve seat.

[0046] 13 illustrates a rear perspective view of a respirator 600 with a seal check device 620 placed on the inside of a face piece 610. The face piece 610 is a composite structure and includes a face seal 611 configured to contact and form a seal with the wearer's face, and a body portion 612 joined to the face seal, the body portion providing a forward section of the body portion 612 where an outer cover 630 is disposed on the exterior surface of the face piece 610. The seal check device 620 is disposed on the inside of the face piece 610 and coupled to the cover 630. The face seal 611 can comprise a silicone material, while the body portion 612 can be semi-rigid and comprise a polymeric material. An example of a face piece is described, for example, in U.S. Pat. No. 8,820,326.

[0047] 14 and 15, the cover 630 includes a port 633 bounded by a connection 635 for receiving a filter cartridge. While shown as a screw-thread connection, any other suitable cartridge connection may be employed. The port 633 is aligned with a seal check device opening located at the rear of the face portion 610. In this view, the port 633 can serve as an inhalation port; in the case of the seal check device 100, the first opening 113 of FIG. 1 is aligned with the port 633. The cover further includes a second port 643 spaced apart from the first port 633. The second port 643 can serve as an exhalation port. In the case of the seal check device 100 of FIG. 1, the second opening 123 of FIG. 1 is aligned with the exhalation port 643. A screw-thread connector or any other suitable type of connector may be provided on the connection 635 surrounding the port 633 to allow a suitable attachment to be connected. Examples of possible attachments include a filter cartridge containing a nonwoven filter material and an adsorbent for adsorbing organic vapors. The port 633 in the cover 630 can be connected to a filter cartridge for filtering inhaled air. In FIG. 14 , the inhalation port 633 is aligned with an opening on the valve seat of the seal check device. In other embodiments, the seal check device can be applied to the exhalation port. To achieve a negative pressure seal check, the seal check device can be attached to a chemical or particulate filtration cartridge, and can be modified for respirators with dual inhalation cartridges, as desired. To achieve a positive pressure seal check, the seal check device can be arranged on the exhalation port 643.

[0048] An opening 639, Figure 15, can be provided adjacent the intake port on the cover 630 to accommodate a push button 640, such as that shown in Figure 14. The push button 640 is aligned with the second end of a lever assembly that is located below the face seal so that when the push button 640 is pressed, it actuates the second end of the lever assembly to perform a seal check procedure.

[0049] Advantageously, a respirator having a seal check device configured in this manner minimizes perforation of holes in the face piece 610 of Figure 13, reducing the source of unwanted air leaks. Seal check devices as described herein can also be releasably installed, allowing the wearer to remove the seal check device for cleaning and to replace components of the seal check device in the event of damage. This can be achieved by providing any suitable attachment feature, such as a snap-on latch, to attach the seal check device to the interior of the face piece.

[0050] Various other modifications and alterations of the present invention will be apparent to those skilled in the art upon reading the foregoing disclosure without departing from the spirit and scope of the invention, and all such modifications and alterations are intended to fall within the scope of the appended claims.

Claims

1. 1. A seal check device comprising: a valve seat having an opening, and a lever assembly arranged rearward of the valve seat and adjacent to the opening; the lever assembly includes a lever having a first end coupled to a valve member configured to close the opening and a second end accessible for contact from a front side of the valve seat, the lever supported on a pivot portion and movable about the pivot portion, movement of the lever about the pivot portion causes the valve member to move toward or away from the valve seat, and the lever is operable to actuate the valve member toward the opening and maintain closure of the opening by applying a force on the second end of the lever from the front side of the valve seat.

2. The seal checking device of claim 1 , wherein the lever is movable in a plane intersecting the opening.

3. The seal check device of claim 1 or 2, wherein the valve seat includes a valve disposed in the opening rearward of the valve seat.

4. 4. The seal check device of claim 3, wherein the valve member includes a valve cover configured to contact a flexible flap when the lever is actuated, the flexible flap covering the opening and preventing air from flowing from a forward side of the valve seat into the opening.

5. 3. The seal check device of claim 1, further comprising a flexible flap arranged in the opening on the front side of the valve seat, the flexible flap allowing air to flow in one direction from the rear side of the valve seat to the outside of the opening.

6. 6. The seal check device of claim 5, wherein the valve member includes a valve cover configured to actuate toward the opening to cover the opening without contacting the flexible flap to prevent air flow through the opening.

7. 3. The seal check device of claim 1 or claim 2, wherein a first end of the lever includes a pair of bifurcated arms, each arm forming a connection for the valve member, and a second end of the lever includes a contact area for actuating the lever.

8. 8. The seal checking device of claim 7, wherein the lever is pivotally mounted on a support frame via a hinge connection formed with the support frame, the support frame being mounted to a rear side of the valve seat.

9. 9. The seal checking device of claim 8, wherein the support frame includes a pair of slots, each slot accommodating a connection between the bifurcated arm and the valve member, the slots defining a track along which the respective connection is permitted to move when the lever is actuated.

10. 8. The seal checking device of claim 7, wherein the lever is pivotally mounted on the valve seat via a hinge connection formed with the valve seat.

11. 11. The seal check device of claim 10, wherein a rear side of the valve seat includes a raised wall disposed between the bifurcated arm and the valve member, the raised wall defining a pair of slots, each slot accommodating a connection between the bifurcated arm and the valve cover, the slots defining a track along which the respective connection is permitted to move when the lever is actuated.

12. The seal check device of claim 7 , wherein the connection between the bifurcated arm and the valve cover is configured to be releasable.

13. The lever is a first lever arm including said first end connected to said valve member and an opposite end A pivotally connected on a first hinge; a second lever arm including said second end B accessible for contact from a front side of said valve seat and an opposite end B pivotally connected on a second hinge; The seal check device of claim 10, wherein end A and end B mesh with each other by gear-tooth engagement.

14. 14. The seal checking device of claim 13, further comprising a rear cover forming with the valve seat an openable enclosure for enclosing the valve member, the valve seat opening being defined on the rear cover.

15. 15. The seal checking device of claim 14, wherein the valve member includes a flexible flap arranged in the opening inside the rear cover, the flexible flap configured to actuate toward the opening in the rear cover to cover the opening when the lever is actuated to prevent air from flowing from a front side of the valve seat into the opening.

16. The seal checking device of claim 15, wherein a first end of the first lever arm extends into an opening in the rear cover and is coupled to the flexible flap.

17. The seal check device of claim 1 or claim 2, further comprising a biasing member arranged to bias the valve member away from the opening by default.

18. 3. The seal check device of claim 1 or claim 2, wherein the valve seat has a first opening including an intake port and a second opening including an expiratory port.

19. 3. The seal check device of claim 1 or claim 2, wherein the lever extends over an edge of the valve seat.

20. A respiratory system, a facepiece; and a seal check device disposed on an inner surface of the facepiece, the seal check device comprising: a valve seat having an opening; and a lever assembly arranged adjacent to the opening on a rear side of the valve seat, the lever assembly comprising: a lever having a first end coupled to a valve member configured to close the opening and a second end accessible for contact from a front side of the valve seat, the lever supported on a pivot and movable about the pivot, movement of the lever about the pivot causes the valve member to move toward or away from the valve seat, the lever operable to actuate the valve member toward the opening and maintain closure of the opening by applying a force on the second end of the lever from the front side of the valve seat.

21. 21. The respirator of claim 20, wherein the face portion includes a resilient face seal and a cover disposed on an exterior surface of the face seal and coupled to the seal check device, the cover including an intake port aligned with an opening on a valve seat of the seal check device.

22. 22. A respirator according to claim 20 or claim 21, wherein the intake port is connected to a filter cartridge.

23. 22. The respirator of claim 20 or claim 21, wherein the cover includes a button adjacent the inhalation port, the button aligned with the second end of the lever assembly below the face seal, the button being pressurized to actuate the lever assembly.

24. 22. A respirator according to claim 20 or claim 21, wherein the lever assembly is disposed entirely below the face seal without any parts extending through the face seal.

25. 22. The respirator of claim 20 or claim 21, wherein the seal check device is releasably mounted to the respirator.

Images