DESCRIPTION

RELATED APPLICATION

[Para 1 ] This application claims the benefit of U.S. Provisional Application No. 63/1 1 2,993, filed on November 12, 2020.

FIELD OF THE INVENTION

[Para 2] The present invention is generally directed to pressure regulators. More particularly, the present invention is directed to a pressure regulator having a closure-resisting mechanism to increase the flow capacity through the regulator.

BACKGROUND OF THE INVENTION

[Para 3] A pressure regulator is a valve that controls the pressure of a fluid or gas to a desired value. The pressure regulator may be a pressure reducing regulator which reduces the input pressure of a fluid or gas to a desired value at its output. It is a normally open valve that is installed or positioned upstream of pressure sensitive equipment. The pressure regulator uses feedback of the regulated pressure as input to a control mechanism, such as actuated by a spring-loaded diaphragm or piston reacting to changes in the feedback pressure to control the valve opening. [Para 4] Pressure regulation valves are used in a wide variety of applications, including fueling applications. The pressure regulator may be designed for use in aircraft or other refueling to protect the receiving aircraft or other transport vehicle from excess pressure and damage due to pressure surges. It is desirable in fueling applications that the pressure regulator not only provide surge pressure protection, but also that the overall pressure drop through the fully open valve be the lowest possible so as to contribute to shorter refueling times. Maximizing the gallons-per-minute during a refueling cycle results in the shortest duration to complete a fueling cycle, allowing an operator to fuel more planes, or other vehicles, in a day and prepare them for operation more quickly.

[Para 5] Pressure regulation valves with automatic spring actuation typically share a common performance shortcoming of beginning to constrict flow prior to the pressure set point of the regulator being reached while pressure begins increasing in the fluid pathway. In prior pressure regulators, flow is constricted by a closure element in the valve to introduce a pressure drop to the flow through the valve, reducing the inlet pressure to a lower downstream pressure. However, this constriction begins to act before the set point of the regulator is achieved, resulting in a limitation of the flow capacity that can be passed through the valve once the closure element of the regulator begins translating. [Para 6] The nature of the helical compression spring design used in these regulators is such that there is a first load for the open position of a regulator and a second load for the closed position of the regulator. Helical compressions require that the first load is less than the second load due to wire deflection when compressed, resulting in the open position having a lower spring force than the closed position spring force within a regulator. This causes the regulator to begin closing at a pressure lower than set point as the first load of the spring is surpassed by the force developed by the pressure diameter of the closure element.

[Para 7] It would be desirable for the regulator to not choke flow until a particular pressure set point has been reached so as to increase the flow capacity through the regulator valve. The present invention fulfills this need, and provides other related advantages.

SUMMARY OF THE INVENTION

[Para 8] The present invention resides in a pressure regulator, such as a hose end pressure regulator, that is designed and configured to not choke flow or close until a particular pressure set point has been reached so as to increase the flow capacity through the regulator. The pressure regulator of the present invention maximizes flow during a flow cycle, such as a fueling cycle, and thus contributes to shorter flow or refueling cycle times.

[Para 9] The pressure regulator generally comprises a pipe defining a fluid pathway between a fluid inlet and a fluid outlet. A closure mechanism includes a seat within the pipe and a closure element movable between a biased open position spaced apart from the seat that permits fluid to flow through the fluid outlet and a closed position against the seat to inhibit or prevent the flow of fluid through the fluid outlet. A closure resisting mechanism is disposed outside of the fluid pathway. The closure resisting mechanism applies an additional open bias force, or a closure resisting force, to the closure element to prevent the closure element from moving into the closed position against the seat until a predetermined fluid pressure set point is reached, corresponding to a predetermined fluid pressure within the fluid pathway.

[Para 10] The pipe may be comprised of a hose adapter portion at one end and a nozzle adapter portion at an opposite end. A tube portion and a bulb portion are disposed between the hose adapter portion and nozzle adapter portion. The seat of the closure mechanism may be disposed within the bulb portion of the pipe.

[Para 1 1 ] The closure element may comprise a hollow tubular piston. The closure element may define at least a portion of the fluid pathway. The closure resisting mechanism may be disposed between an inner wall of the tube portion of the pipe and an outer wall of the closure element.

[Para 12] The closure mechanism includes a main spring that applies an opening bias force to the closure element. The main spring may comprise a helical compression spring.

[Para 1 3] The closure resisting mechanism includes a secondary holding spring that applies at least a portion of the force, or a closure resisting force, to the closure element. The holding spring may comprise a helical compression spring. [Para 14] The closure resisting mechanism may include a collapse ring having free ends that are spaced apart from one another when the closure element is in an open position. The free ends are moved towards one another as the closure element moves towards the closed position. The collapse ring may be moved linearly within a tube having a first diameter portion and a second smaller diameter portion as the closure element is moved towards this closed position. The collapse ring may provide at least a portion of the closure resisting force to the closure element.

[Para 1 5] Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[Para 16] The accompanying drawings illustrate the invention. In such drawings:

[Para 1 7] FIGURE 1 is a perspective view of a pressure regulator embodying the present invention;

[Para 18] FIGURE 2 is an environmental perspective view illustrating the pressure regulator connected to a hose at one end thereof and a nozzle at an opposite end thereof, such as in a fueling application, in accordance with the present invention; [Para 19] FIGURE 3 is a top and partially sectioned view of the pressure regulator, illustrating interconnection of portions thereof, in accordance with the present invention;

[Para 20] FIGURE 4 is an enlarged cross-sectional view of area “4” of FIG. 3;

[Para 21 ] FIGURE 5 is a cross-sectional view of the pressure regulator in an open position;

[Para 22] FIGURE 6 is an enlarged cross-sectional view of area “6” of FIG. 5, illustrating a closure resisting mechanism embodying the present invention;

[Para 23] FIGURE 7 is a partially sectioned view of the pressure regulator in an open position;

[Para 24] FIGURE 8 is a cross-sectional view of the pressure regulator in a closed position;

[Para 25] FIGURE 9 is a partially sectioned view of the pressure regulator in a closed position; and

[Para 26] FIGURE 10 is an enlarged cross-sectional view of area “10” of FIG.

6, illustrating a locking thumb screw, used in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[Para 27] As shown in the accompanying drawings, for purposes of illustration, the present invention is directed to a pressure regulator, generally referred to by the reference number 100. The pressure regulator of the present invention overcomes the shortcomings of prior pressure regulation valves with automatic spring actuation which begin to constrict flow prior to the pressure set point of the regulator being reached while pressure begins increasing in the fluid pathway.

[Para 28] With reference to FIG. 1 , the pressure regulator 100 of the present invention may be generally cylindrical and have a pipe configuration, as illustrated. The pressure regulator 100 includes a fluid inlet 102 at one end thereof and a fluid outlet 104 at an opposite end thereof, and defining a fluid pathway therebetween.

[Para 29] With reference now to FIG. 2, the pressure regulator 100, sometimes referred to herein as a pressure control valve or pressure regulator valve, may be incorporated and/or used in connection with a fueling or other fluid transfer assembly. Such an assembly includes a hose assembly 10, which may include a break assembly for attachment and detachment of the hose assembly 10 to the pressure regulator 100, and a nozzle assembly 12 at an opposite end thereof. Fluid flows from the hose assembly 10, through the pressure regulator 100, and to the nozzle assembly 12. The nozzle assembly 12 may be connectable to a fuel port of a vehicle, such as an aircraft, rail car engine, an automobile, a boat, or any other vehicle. It will also be understood that while the present invention is particularly adapted for use in fueling applications, it can also be utilized in other applications where fluid is transferred from one tank or location to another. It will be understood that the fueling or fluid tank to which the hose assembly is connected to and extends from may be stationary, such as an above-ground tank or even a subterranean tank, or mobile, such as a fuel tanker truck or the like. The pressure regulator 100 of the present invention maximizes the gallons per minute during a fluid transfer cycle, such as a refueling cycle, resulting in the shortest duration to complete such fueling cycle, allowing an operator to fuel more planes, or other vehicles, tanks, etc., in a day or over a given period of time.

[Para 30] With reference now to FIGS. 1 -4, the pipe, forming the main body of the pressure regulator, may be comprised of a plurality of sections or portions, as illustrated. At the inlet end of the pressure regulator 100 is an upstream hose adapter portion 106. The hose adapter portion 106 acts as a pressure boundary and provides means for connecting the pressure regulator 100 to a fluid flow path, such as a hose. At the generally opposite end of the pressure regulator 100 is a downstream nozzle adapter portion 108, which acts as a pressure boundary and provides means for connecting the pressure regulator 100 to a flow path, such as a nozzle. A bulb portion 1 10 and a tube portion 1 1 2 are disposed between the hose adapter portion 106 and the nozzle adapter portion 108. Typically, the bulb portion 1 10 is connected to the hose adapter portion 106 and the tube portion 1 1 2 is connected to the nozzle adapter portion 108, as illustrated. These portions 106-1 1 2 collectively form the main body pipe of the pressure regulator 100. It will be understood, however, that the pressure regulator 100 may include additional segments or portions, or fewer segments or portions.

[Para 31 ] With particular reference to FIGS. 3 and 4, fasteners, such as screws 1 14 and nuts 1 16, may be used to securely connect the portions 106-1 12 to one another. Protective bumpers 1 1 8, such as being comprised of elastomeric material or the like, may be disposed over these connection points and any other sensitive areas of the pressure regulator 100 to protect these areas against damage as the pressure regulator 100 is in use and may come in contact with the ground or other objects. In this manner, the pressure regulator 100 is protected from impact damage if dropped during usage or handling, or otherwise comes into abrupt and forceful contact with other objects.

[Para 32] With continuing reference to FIGS. 3 and 4, a gland retainer 120 contains a gland ring 1 22 and maintains structural integrity of the upstream closure element seal glands. Gland retaining screw 1 24 affixes the gland retainer to the bulb portion 1 10, providing structural clamping of the gland retainer 1 20 to resist pressure loads transferred like by closure element, O- rings and seals and the like, including O-ring 1 26 and closure element seal 128.

[Para 33] With reference to FIGS. 1 and 3, the hose adapter portion 106 may include one or more upstream race rings 1 30 to provide a surface for ball bearings of the hose connector to roll against the hose end adapter portion 106 in a ball race swivel joint between the pressure regulator 100 and the upstream flow path. An O-ring 1 32 or swivel ring may perform a sealing function at the upstream joint between the pressure regulator 100 and the hose assembly 10 to prevent release of service fluid to the atmosphere. Similarly, at the downstream end at the nozzle adapter portion 108 one or more race rings 1 34 may provide a surface for ball bearings of the nozzle assembly 1 2 to roll against the adapter portion 108 in a ball race swivel joint between the pressure regulator 100 and the downstream flow path. Also, an O-ring or swivel ring

I 36 may provide a wear-resistant bearing and perform a sealing function at the downstream joint between the nozzle adapter portion 108 and the nozzle assembly 12 to prevent release of service fluid to the external atmosphere.

[Para 34] With reference now to FIG. 5, a strainer 1 38 strains the flow through the regulator valve 100, removing particulate matter via wire mesh openings in a conical configuration, as illustrated. This is a replaceable, optional trim component of the pressure regulator 100. A retaining ring 140 provides a means for mechanically retaining the strainer screen 1 38 within the pipe of the pressure regulator 100, such as in the hose adapter portion 106, as illustrated.

[Para 35] With continuing reference to FIG. 5, the bulb portion of the pipe

I I 0 acts as a pressure boundary and houses a seat assembly 142 of a closure mechanism of the pressure regulator 100 used for closure of the main flow through the pressure regulator 100. The seat retainer 144 is affixed to the bulb portion 1 10 and provides attachment and housing of a seat 146 and a relief ball check feature. The seat retainer 144 holds the seat 146, which is typically comprised of an elastic material, in place. The seat retainer 144 may be a replaceable trim component.

[Para 36] The seat retainer 144 also provides housing for the relief ball check feature, which comprises a relief spring 148 which is a helical compression spring that provides a resisting load that tends to keep an elastomeric ball 1 50 in the closed position when loaded or unloaded by pressure. The relief spring 148 allows for translation of the elastomeric ball 1 50 off of the seat 144 when a positive pressure differential is developed in the downstream-to-upstream direction, relieving downstream pressure when the upstream pressure is lower than the downstream pressure. The ball 1 50 is an elastomeric sphere that acts as the closure element of the relief feature in the seat retainer 144 and bulb portion 1 10. The ball 1 50 allows pressure to pass from downstream to upstream when a differential is developed, and seals against a pressure differential in the upstream to downstream direction.

[Para 37] The closure mechanism also includes a closure element 1 52 which is movable between a biased open position, spaced apart from the seat 146, as illustrated in FIGS. 5 and 7, and a closed position against the seat 146, as illustrated in FIGS. 8 and 9 to inhibit or prevent the flow of fluid through the fluid outlet 104 of the pressure regulator 100. The closure mechanism also includes a main spring 1 54, which may be a compression spring, that biases the closure element 1 52 in an open position. The main spring 1 54 may be a helical compression spring that provides resisting load that tends to open the closure element 1 52. The main spring 1 54 compresses under internal pressure load, allowing the main flow path to be shut off at a specified main flow downstream pressure.

[Para 38] The closure element 1 52, in a particularly preferred embodiment, as illustrated herein, has a hollow tubular configuration such that fluid flows therethrough, and the closure element 1 52 defines at least a portion of the fluid pathway through the pressure regulator 100. This portion of the fluid pathway is defined by the inner surface of the tubular closure element 1 52. The closure element 1 52 has two different sealing diameters to create a pressure area, such as the portion 1 56 of a smaller diameter and portion 1 58 of a larger diameter. The pressure area acts between atmospheric pressure and internal fluid pressure, creating a differential pressure that acts against the spring forces of main spring 1 54 resisting the closure element’s piston translation towards the closed position.

[Para 39] An aperture is formed in the pipe, such as through the tube portion 1 1 2 and a screen 160, such as in the form of a wire mesh disk, is inserted into the aperture to provide atmospheric pressure to the closure element piston 1 52 or the pressure area differential. When the pressure differential overcomes the biasing of the main spring 1 54 the closure element 1 52 moves towards the closed position until it contacts the seal 146. The seal 146 may be comprised of an elastomeric material and the closure element sealing edge compressing against the seal 146 during closure shuts off flow through the pressure regulator 100. This prevents fluid from flowing through the fluid pathway and out of the fluid outlet 104 of the pressure regulator valve 100. This occurs when the downstream pressure increases sufficiently to a point to overcome the forces of the bias of the main spring 1 54. The pressure differential between portions 1 56 and 1 58 of the closure element piston 1 52 results in these forces acting against compression spring 1 54 until the spring forces are overcome and the closure element is moved into the closed position against the seal 146.

[Para 40] With reference now to FIG. 6, a downstream piston O-ring seal 162 and a cap seal 164 provides a low-friction seal between internal pressure and external atmospheric pressure at the closure element outside diameter portion 1 58. Similarly, when upstream O-ring seal 166 and cap seal 168 provides a low-friction seal between internal pressure and external atmospheric pressure at the outside surface of the smaller diameter portion 1 56 of the closure element 1 52.

[Para 41 ] As mentioned above, a common performance shortcoming of such pressure regulators is the beginning to constrict flow prior to the predetermined pressure setpoint of the pressure regulator being reached while pressure begins increasing in the fluid pathway. This results in a limitation of the flow capacity that can be passed through the pressure regulator valve once the closure element of the pressure regulator begins translating towards the closed position. The pressure regulator begins closing at a pressure lower than the setpoint as the first load of the main spring 1 54 is surpassed by the force developed by the pressure diameter of the closure element 1 52.

[Para 42] To increase the flow capacity through the pressure regulator valve 100, the closure element 1 52, sometimes referred to herein as a piston, must be held open with force equal to or exceeding the first load of the spring 1 54 actuating the closure element 1 52. This effectively increases the initial pressure value at which the regulator 100 begins to close and constrict flow. The pressure regulator valve 100 of the present invention has been designed to integrate a closure resisting mechanism that provides additional linear force in the direction of the main regulating compression spring 1 54 at the open position, increasing the total force resisting the closure element 1 52. The closure resisting mechanism operates automatically and is spring actuated in response to pressure loads developed by the main flow path of the pressure regulator valve 100. One advantage of the present invention is that the closure resisting mechanism is external to the fluid flow path of the pressure regulator 100, maximizing the area of the internal flow path within the pressure regulator 100 to provide the greatest capacity for the envelope size of the valve.

[Para 43] The closure resisting mechanism includes a secondary holding spring 1 70 that applies an additional open bias force, or a closure resisting force, to the closure element to prevent the closure element from moving into the closed position against the seat 146 until a predetermined fluid pressure set point is reached. The secondary holding spring 1 70 may comprise a helical compression spring. Typically, as will be more fully described herein, the closure resisting mechanism also includes a collapse ring 1 72 which provides at least a portion of the additional open bias force or closure resisting force, to the closure element 1 52 to temporarily hold it open and prevent the closure element 1 52 from moving into the closed position against the seat 146 until a predetermined fluid pressure set point is reached.

[Para 44] As mentioned above, one benefit of the present invention is that the closure resisting mechanism is disposed outside of the fluid flow pathway of the pressure regulator 100. This may be done, as illustrated herein, with the closure resisting mechanism being disposed between an inner wall of the tube portion 1 1 2 and an outer wall of the closure element 1 52, as illustrated in FIG.

6.

[Para 45] The closure resisting mechanism includes a sleeve mechanism comprising an inner sleeve 1 74 and an outer sleeve 1 76. The wire mesh screen 160 allows air exchanges into the sleeve mechanism cavity through the tube portion 1 1 2. Air flow passageways 1 78 and 180 may be formed through the sleeve mechanism to provide atmospheric air to the main spring 1 54, as needed.

[Para 46] A yoke 182 mechanically couples the loads at the closure element

1 52 to the outer sleeve 1 76. A yoke set screw 1 84 may provide coupling between the yoke 1 82 and the outer sleeve 1 76. The outer sleeve 1 76 provides a means for translating the pressure load applied to the closure element 1 52 to the collapse ring 1 72. The inner sleeve 1 74 provides means for compressing the resetting sleeve secondary holding spring 1 70 in response to the collapse ring 1 52 wedging radially inward during deflection, providing additional load to the closure element 1 52 at the open position. As can be seen in the illustrations, such as in FIG. 6, the secondary holding spring 1 70 is disposed within the cavity between the inner and outer sleeve 1 74 and 1 76.

[Para 47] The collapse ring 1 72 is disposed within a tube having varying diameters. The tube may comprise the inner surface of the tube portion 1 1 2, as illustrated. In the open position, where the closure element 1 52 is spaced away from the seal 146, the collapse ring 1 72 is disposed within a tube groove 186 having a first diameter portion which is larger than a second diameter portion 188 of the tube. Typically, there is a ramp portion 190 between the groove tube 1 86 and the second smaller diameter portion 1 88. The tube 1 1 2 joins pressure boundaries and contains the profile for the deflecting collapse ring 1 72.

[Para 48] A wedge ring 1 92 provides a means for a spring load to resist the inward deflection of the collapse ring 1 72, maintaining the collapse ring 1 72 in the larger diameter portion of the tube groove 1 86 until sufficient pressure is developed in the main flow path of the pressure regulator 100. The wedge ring 192 is attached to the inner sleeve 1 74 and with the secondary holding spring 1 70 installed provides additional compression force at the open position as it holds the collapse ring 1 72 in place in the larger diameter tube bore 186.

[Para 49] With reference now to FIG. 7, the collapse ring 1 72 is a toroidal ring with a section cut out or removed so as to create free ends 194 and 1 96, spaced apart from one another to form a gap or space 198 therebetween.

When the closure element 1 52 is in the open position, as illustrated in FIG. 7, the free ends 194 and 1 96 of the collapse ring 1 72 are spaced apart from one another a relatively large degree to create a large space 198 therebetween. However, as downstream pressure increases within the pressure regulator 100, the collapse ring 1 72 is moved linearly within the tube from the tube groove having the first diameter portion towards the second smaller diameter portion ring 1 72 such that the free ends 1 94 and 1 96 come closer to one another and the space 1 98 therebetween decrease as the closure element 1 52 is moved into the closed position, as illustrated in FIG. 9.

[Para 50] As mentioned above, the outer sleeve 1 76 is coupled to the closure element 1 52, thereby translating the pressure load from the flow path to components of the closure resisting mechanism. The outer sleeve 1 76 loads the collapse ring 1 72 linearly as pressure increases in the main flow path. The conical ramp section 1 90 of the internal profile of the tube 1 1 2 provides a first component in the inward radial direction as the outer sleeve 1 76 loads the collapse ring 1 72. After sufficient load is developed in the secondary spring 1 70 of the mechanism, the collapse ring 1 72 deflects radially inwardly enough to slip into the smaller inside diameter portion 1 88 of the tube 1 1 2, no longer resisting the travel of the closure element 1 52 in the pressure regulator 100. The pressure regulator 1 00 then controls pressure normally with piston translation of the closure element 1 52 and constriction to introduce a pressure drop across the seating edge of the closure element 1 52.

[Para 51 ] The collapse ring 1 72 acts as a locking feature which prevents closure of the closure element 1 52 until sufficient pressure is developed, whereby it loads the wedge ring 1 92 sufficiently to be able to deflect inwardly sufficiently to fit inside the smaller bore 1 88 of the tube 1 1 2 as the piston closure element 1 52 is moved into the closed position. Thus, it can be seen in FIG. 7 that the gap or space 1 98 between the free ends 1 94 and 1 96 of the collapse ring 1 72 is open and large when the piston closure element 1 52 is in an open position, and thus the collapse ring 1 72 is in a more relaxed position. [Para 52] However, as the piston closure element 1 52 begins to close towards a closed position, as illustrated in FIG. 9, the collapse ring 1 72 is moved from the tube groove 1 86 along the ramp portion 1 90 and into the smaller diameter portion 188 of the tube and along the wedge ring 192 against the resisting load of the resetting sleeve spring or secondary holding spring 1 70. The secondary holding spring 1 70 and wedge ring 1 92 configuration in conjunction with the collapse ring 1 72 and the movement of the collapse ring 1 72 to an increasingly compressed state, as illustrated and described above, serves to hold open the closure element 1 52 below a pressure threshold, which increases the number of gallons of fluid, such as fuel, passed through the pressure regulator 100 as pressure begins to rise within the fluid flow pathway. [Para 53] Thus, the pressure regulator 100 does not choke flow until a particular predetermined pressure set point has been reached to overcome this wedging and resisting spring load, after which the pressure regulator 100 will regulate flow like usual, without the hold-open feature. In other words, the wedge mechanism reaches a threshold after which it can no longer hold the pressure regulator 100 open, and the pressure regulator 100 begins to choke flow to reduce downstream pressure, which also reduces the flow rate and gallons-per-minute through the pressure regulator 100 until it is closed. As described and illustrated above, this is accomplished outside of the fluid pathway so as not to construct fluid flow through the pressure regulator device

100.

[Para 54] A buttonhead screw 200 closes the threaded holes in the tube 1 12 during normal use to mitigate dirt accumulation in the tube. A washer 202 provides a wear-resisting surface for the button screw 200 to be torqued against the tube 1 1 2, while also ensuring that the button screw 200 cannot insert and interfere with the outer sleeve 1 76.

[Para 55] With reference now to FIG. 10, in place of the buttonhead screw 200, a locking thumb screw 204 may be inserted in its place within the aperture of the tube 212. The thumb screw 204 acts as a lockout device when threaded into the tube, blocking the resetting sleeve mechanism, resulting in holding the piston closure element 1 52 open when internal pressures would normally begin closing the closure element 1 52. The regulator 100 can be deactivated by installing this lockout screw, so as not to constrict the flow path in response to pressure changes due to the linear travel of the outer sleeve 1 76 being blocked by the interfering feature of the lockout screw 204. The buttonhead socket cap screw 200 is installed for normal operation where the regulation feature of the regulator valve 100 is active, as discussed above.

[Para 56] The pressure regulator 100 also preferably includes a number of additional O-rings and other seals. It may include O-rings and seals to prevent internal pressure and fluid from releasing to the external atmosphere. It may also include O-rings and seals between the portions 106-1 1 2 of the pipe, O- rings and seals that facilitate linear translation of the closing element 1 52 in a sealed manner, as well as sealing between the seat retainer 144 and the bulb portion 1 10 of the pipe. Additional O-rings and seals may be incorporated into the pressure regulator 100 as needed.

[Para 57] Although several embodiments have been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims.