Pressure responsive fluid flow control valves
In one set of embodiments a selected section of tubular stock has its ends welded together to form a pillow-like pressure sensing device with an entry tube and an exit tube each configured to facilitate insertion of the pressure sensing device into the flow path of IV infusate in an IV administration set or system. Fluid pressure in excess of a predetermined amount reconfigures the pressure sensing device from a generally oval configuration to a generally circular configuration to restrict and/or cut off fluid flow into the device while permitting fluid flow from the device to reduce the fluid pressure again reconfiguring the device back to its generally oval configuration and permitting fluid flow into and through the device. In other embodiments a fluid pressure sensing device is formed with a fluid entry chamber and a fluid exit chamber interconnected by a passageway and provided with a piston that reacts to an increase in fluid pressure above a predetermined amount to close off the interconnection between the chambers and fluid flow into the exit chamber. Continued fluid flow from the eit chamber results in a reduction of fluid therein and reopening of the fluid passageway between the chambers.
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1. Field of the Application
This invention relates to fluid-flow control valves, and more particularly to pressure responsive fluid-flow control valves particularly adapted for use with Intravenous (IV) infusion applications.
2. Background Of The Invention—Description Of Prior Art
In the administration of blood, and other fluids, it is sometimes required to rapidly increase the flow rate through the IV set to administer a large or larger volume of IV fluid. This is usually done by applying pressure to the IV line. One very common means of doing this is by manually squeezing a bladder or bulb in the IV administration set. When that is done, especially if the needle or cannula, or the other venous access device, cannot accommodate the sudden increase in fluid-flow, the pressure in the line usually quickly rises to a large and often dangerous value. Such pressure can easily exceed 20 psi (greater than 1,000 mm Hg) for a brief period. The use of a syringe to rapidly infuse fluid in pediatric patients through a small needle can produce a similar unacceptable pressure. The generally accepted safe pressure threshold is about 300 mm Hg, or about 6 psi. If the venous access device is not seated properly, this high pressure can be applied to the patient's veins, and damage the vein and surrounding tissue. In addition, some devices in the IV line are not made to withstand such a high pressure, and can leak when subjected to this pressure. It is, therefore, desirable and necessary to protect the patient/recipient from such dangerous, and possibly damaging, high pressure.
There are numerous examples of valves for use with IV (intravenous) administration sets and devices. However, valves, such as those shown and described in U.S. Pat. No. 4,146,055 patented on Mar. 27, 1979 to F. E. Ryder et al for “Valve Structure”; U.S. Pat. No. 4,230,300 patented on Oct. 28,1980 to H. L. Wiltse for “Flow Metering and Shut-Off Valve”; and U.S. Pat. No. 4,332,369 patented on Jan. 1, 1982 to M. Gordon et al for “Adjustable In-Line Intravenous Valve With Locking Mechanism”; require human intervention to adjust the valves which are in no way automatically, and/or otherwise, self-responsive to changes in fluid-flow pressure. While a valve such as the one shown and described in U.S. Pat. No. 5,453,097 patented on Sep. 26, 1995 to J. R. Paradis for “Control of Fluid Flow” may very well permit fluid under unacceptable and dangerous pressures to flow into and out from the valve and from there to a person receiving the fluid infusion. There are also shown and described in U.S. Pat. No. 4,256,104 patented on Mar. 17, 1981 to A. J. Muetterties et al for “Equipment Sets and System For The Sequential Administration of Medical Liquids At Dual Flow Rates”; U.S. Pat. No. 4,316,460 patented on Feb. 23,1982 to J. N. Genese et al for “Gravitational Flow System For The Sequential Administration of Medical Liquids”; and in U.S. Pat. No. 4,417,577 patented on Nov. 29, 1983 to J. N. Genese for “Gravitational Flow System For The Sequential Administration Of Medical Liquids”; but such systems are relatively complex and shut down one IV where a second one is turned on and then act to restrict air-flow when the second IV is finished.
Other valves intended for use with IV administration sets; such as, for example, those shown and described in U.S. Pat. No. 4,515,588 patented on May 7,1985 to P. J. Amendolia for “I.V. Flow Regulator” and in U.S. Pat. No. 5,988,211 patented on Nov. 23, 1999 to W. D. Cornell for “I.V. Flow Controller” are provided for flow rate control, and in fact show, describe and teach that there are to be both inlet and outlet fluid-flow chambers and that the pressure in the outlet fluid-flow chamber has to exceed the pressure in the inlet fluid-flow chamber to permit passage of fluid to the patient and, as such, unacceptable high fluid-flow pressure entering the inlet chamber will necessitate an even higher and even more unacceptable fluid-flow pressure to the fluid recipient. On the other hand a pressure control valve, such as the one shown and described in U.S. Pat. No. 4,787,413 patented to J. M. Saggers on Nov. 29, 1988 for “Pressure Control Valve”; shows, describes and teaches the use of an intermittent on/off air-flow control that incorporates an inflatable sac that receives a bleed-off from an air duct to operate a plate that, in turn, moves a sealing device away from the opening of the air duct to permit air flow for the end use. The sac, however, when air flow pressure is reduced, returns air flow to the air duct and permits movement of the plate, under spring action, to move the sealing device back into position blocking the exit of air from the air duct and thus from the end use. The air entering the Saggers air-sac does not pass through the sac but is expelled, when expelled, through the air entry opening to the air sac. As such the valve is obviously only suitable for gasses and not for IV uses. It requires manual adjustment by a rotatable shaft and vents the air to the outside rather than confining it.
SUMMARY OF THE INVENTIONIt is therefore an object of this invention to provide new and novel pressure responsive valves.
It is another object of this invention to provide new and novel fluid pressure responsive valves for incorporation into intravenous administration and infusion sets and systems.
It is yet another object of this invention to provide new and novel fluid pressure responsive valves for incorporation into intravenous administration sets and systems with relative ease, within the fluid-flow path between the source of the fluid and the patient/recipient that is to receive the fluid, and permits normal fluid flow with little or no flow restriction.
It is yet still another object of this invention to provide new and novel pressure responsive valves, primarily for IV use, which are relatively small in size and volume and which are bio-compatable.
It is yet still another object of this invention to provide new and novel pressure responsive valves, primarily for IV use, which respond to a predetermined “critical pressure”.
It is yet still another object of this invention to provide new and novel pressure responsive valves, primarily for IV use, which work passively without operator adjustment and facilitate a normal fluid flow in safe fluid pressures independent of pressure applied to the fluid.
It is yet still another object of this invention to provide new and novel pressure responsive valves, primarily for IV use, which respond to pressures above a predetermined value to reduce or cut-off inflow of fluid to a pressure sensing device while maintaining uninterrupted flow to the recipient.
It is yet still another object of this invention to provide new and novel pressure responsive valves, primarily for IV use, for incorporation into or with a fluid warmer.
It is still another object of this invention to provide new and novel fluid pressure responsive valves, primarily for IV use, that are constructed of materials so that the fluid-flow path can be sterilized and made non-pyrogenic by conventional methods and so that single use thereof is economically feasible.
Other objects of this invention will hereinafter become obvious from the following description of the preferred embodiments of this invention.
The instant pressure response valve (PRV) incorporates a deformable sensor chamber. The geometry of the sensor chamber allows normal fluid-flow to proceed with very low flow restriction when the applied pressure is well below a predetermined “critical value”. When the fluid pressure is at or exceeds the “critical value” the valve functions by change of the geometric configuration of the sensing chamber with sufficient force to either overcome the input pressure seen in the chamber or by action of a valve member to crimp fluid flow tubing to the sensing chamber; or by deforming so as to activate a feature in the valve to cut off fluid flow into the sensor chamber; all without interfering with outflow from the valve to the intended use or user. The pressure in the valve is automatically reduced below the “critical value” by the continued fluid flow from the sensing chamber, or part of the chamber, to once again permit fluid inflow. The pressure responsive valve (PRV) utilizes a small number of simple plastic components to accomplish the pressure limiting function, and to maintain very small size, and small priming volume. The components contacting the fluid are relatively easily formed by injection molding or by welding or sealing tubing components, and are presumably sterilizable by conventional means. Example embodiments of simplified valves employing these mechanisms are shown in the detailed description that follows:
BRIEF DESCRIPTION OF THE DRAWINGSIn the drawings:
With reference to
Tubes 40, 50, 62, 66 and 74 are of conventional construction and use; as are drip chamber 46, bladder 56, and hypodermic needle 76 to a patient/recipient 80. A piece of tape 82 may be utilized to secure needle 76 in place. Thus it should be clear that tubes 40, 50, 62 and 66 and drip chamber 44, bladder 56, valve 64, pressure responsive valve 70, tube 74 and needle 76 together define a fluid-flow path 84 for the delivery of IV fluid 24 from reservoir 22 to a patient/recipient 78. It should be understood that while the various components of IV set 20 have been shown as connected and described herein that other suitable connections may be utilized and additional and/or other components may be employed for IV set or system 20.
Tube 66 (
When pressure responsive valve 70 is installed in IV set 20 (
As fluid 24 exits sensing space 120 the fluid pressure therein will automatically and with no operator intervention be reduced below the “critical limit”. Walls 100, 102 and 104, due to the material and fabrication thereof, will return to their oval disposition (
With reference to
Tube 170 and valve 150 are incorporated into IV set 152 at a suitable location so that the outflow from the IV reservoir (not shown) and IV set components that receive that outflow becomes the fluid inflow through tube 170 and into sensing chamber 156. As long as the pressure exerted on, or by, such fluid remains under a selected “critical pressure limit” the flow of the IV fluid will continue through valve 150 and outflow tube 172 and thence to the recipient of the IV infusion. Should the pressure on and exerted by the IV fluid reach the “critical limit” or be in excess thereof, the oval/pillow like configuration of sensing chamber 156 will become rounder (less oval) and that occurrence will effect a reaction of sensing chamber 156 with response arm 176 of action lever 174 to pivot action lever 174 clockwise (
Inflow tube 216 and pillow-like sensing chamber 206 are incorporated into IV set 202 at a suitable location so that outflow from the IV reservoir (not shown) and IV set components that receive fluid therefrom (not shown) becomes the fluid inflow through tube 216 and into sensing chamber 206. As long as the pressure exerted on or by such fluid remains under a selected “critical pressure” or “critical limit” the flow of the IV fluid will continue through valve 200 and outflow tube 218 and thence to the recipient of the IV infusion. Should the pressure on and exerted by the IV fluid reach the “critical pressure limit” or be in excess therof, the oval/pillow-like configuration of sensing chamber 206 becomes rounder (less oval) and that occurance will effect a reaction of action wall 222 of sensing chamber 206 with piston 220 to move pinch valve 228 against and into inflow tube 216 at pinch/restriction zone 224 to thus reduce or cut-off inflow of the IV fluid into sensing chamber 206. The flow of the IV fluid that is already in sensing chamber 206, however, will continue, under pressure, to flow from sensing chamber 206 and out through exit/outflow port 218. As such the fluid pressure within and exerted by sensing chamber 206 will automatically diminish allowing sensing chamber 206 to return to its oval/pillow-like configuration and its action wall 222 on piston 220 will diminish permitting the inflow of IV fluid through inflow tube 216 through sensing chamber 206 and therefrom to the recipient of the infusion.
Inflow tube 270 and pillow-like sensing chamber 256 are incorporated into IV set 252 at a suitable location so that outflow from the IV reservoir (not shown) and IV set components that receive fluid therefrom (not shown) becomes the fluid inflow through tube 270 and into sensing chamber 256. As long as the pressure exerted on or by such fluid remains under a selected “critical pressure or limit” the flow of the IV fluid will continue through valve 250 and outflow tube 272 and thence to the recipient of the IV infusion. Should the pressure on and exerted by the IV fluid reach the “critical pressure limit” or be in excess therof, the oval/pillow-like configuration of sensing chamber 256 becomes rounder (less oval) and that occurance will effect a reaction of action wall 278 of sensing chamber 256 with action arm 276 to move pinch valve 282 against and into inflow tube 270 at pinch/restriction zone 280, and in coaction with pinch piece 284 to reduce or cut-off inflow of the IV fluid into sensing chamber 256. The flow of the IV fluid that is already in sensing chamber 256, however, will continue, under pressure, to flow from sensing chamber 256 and out through exit/outflow port 272. As such the fluid pressure within and exerted by sensing chamber 256 will reduce allowing sensing chamber 256 to return to its oval/pillow-like configuration and its action wall 276 on piston 274 will diminish permitting the inflow of IV fluid through inflow tube 272 through sensing chamber 256 and therefrom to the recipient of the infusion.
Another embodiment of pressure responsive valve 300 (
IV fluid entering inflow chamber 342, of pressure responsive valve 300, through tube 346, flows through fluid passage 340 and into outflow or exit chamber 344 and then through outflow tube 350 to either other components of the IV set or system or to the intended recipient of the fluid. Should the pressure of, or exerted by, the fluid exceed a “critical limit pressure” the fluid in outflow chamber 344 will exert sufficient pressure on an underside of diaphragm 310 and move valve operator 308 along inner wall 320 of housing 302 until valve cap 316 seats against valve seat 330 and closes fluid passage 340 and the flow of fluid from input chamber 312 into output chamber 344. Since there are no obstructions to fluid flow out from chamber 344 the fluid will flow from chamber 344 through tube 350 and then to other components of the IV set or system and/or then to the recipient of the fluid. As the fluid continues to so flow the pressure in chamber 344 will diminish without operator intervention and diaphragm 310 will move along wall 320 of housing 302 until valve cap 316 moves away from valve seat 330 to again permit fluid flow into valve 300 and on to the recipient all automatically and without operator involvement.
Another embodiment of pressure responsive valve 400 (
Diaphragm 410 is seated on a rim 418 that surrounds an inner wall 420 of housing 402. A tapered valve seat 430, that surrounds valve stem 412, is formed at a lower end of a first ledge 432, that extends out from wall 420 of housing 402 and a second ledge 434 that is supported by a leg 436 that extends out from a wall 438 of housing 402. First ledge 432 and second ledge 434 surround but are spaced from valve stem 412 to form a fluid passageway 440 between a fluid entry or in-flow chamber 442 for valve 402 and a fluid outflow or exit chamber 444 for valve 402. Sides 445 of valve stem 412 are tapered down and out for co-action with correspondingly tapered valve seat 430. A fluid inflow tube 446, of the type described for previously described embodiments, is utilized to connect pressure responsive valve 402 into an IV set or system, of the type described hereinabove and shown in
IV fluid entering inflow chamber 442, of pressure responsive valve 400, through input port 448, flows through fluid passage 440 and into outflow or exit chamber 444 and then through output port tube 452 to either other components of the IV set or system or to the intended recipient of the fluid. Should the pressure of, or exerted by, the fluid exceed a “critical limit pressure” the fluid in outflow chamber 444 will exert sufficient pressure on an underside of diaphragm 410 to flex diaphragm 410 and move valve cap 416 to seat same against valve seat 430 and close fluid passage 440 and the flow of fluid from input chamber 442 into output chamber 444. Since there are no obstructions to fluid flow out from chamber 444 the fluid will flow from chamber 444 through port 450 and then to other components of the IV set or system and/or then to the recipient of the fluid. As the fluid continues to so flow the pressure in chamber 444 will diminish without operator intervention and diaphragm 410 will flex or return back until valve cap 416 moves away from valve seat 430 to again permit fluid flow into valve 400 and on to the recipient all automatically and without operator involvement.
At times an IV warming device 570 (
The instant pressure responsive valves (PRV's) operate as a simple components of IV infusion sets and/or systems. The set must be a closed system to maintain both sterility of the infusate, and not expose workers in the field to unsafe fluids. The PRV's are constructed of materials so that the fluid path is biocompatible-compatible with blood products, and does not leach out any substance which is harmful to tissue. Its flow path is readily sterilized and rendered pyrogen free by commonly used means. It is relatively small, with small priming volume, and capable of being placed in-line in the set. It does not contain any electrical components. It operates passively, without requiring the user to make any adjustments or settings and can deliver infusate at unregulated pressures 0 to greater than 1500 mm Hg.
The instant pressure responsive valves allow for sudden increase in flow so long as the applied pressure remains below a “critical pressure limit or value”, (in the range of about 250 to 350 mm Hg for instance). The valve has a minimal flow resistance when used at typical IV pressures of 50-100 mm Hg, as well as at increased pressures which are below the said “critical value”. The respective valves are formed to provide valves of single “critical pressure limits or values”. It being understood that valves with other “critical pressure limits or values” may be fabricated depending on proposed uses and fluids to be infused.
The present invention can be used as a separate device in an IV set, can be built into a fluid administration set, or can be integrated into an existing device. The described PRV embodiments may, for example, be permanently bonded to the inflow tubing of a device such as the Blood Heater Disposable Set, which is one embodiment of U.S. Pat. No. 6,480,257, “Heat Exchanger Usable in Wearable Fluid Heater.” to protect the device from excessive pressure, or to protect the patient distal to the device, from excessive pressure. The disclosed PRV's may may be fabricated with luer or other fittings for insertion into an IV administration set or system.
While only certain specific preferred embodiments of the invention have been described, it is understood that, many variations thereof are possible without departing from the principals of this invention as defined in the following claims.
Claims
1. A fluid pressure responsive valve, for insertion into a predetermined fluid-flow path, and responsive to fluid pressure of a predetermined amount; comprising:
- (a) deformable fluid-pressure sensing means insertable into a fluid-flow path and responsive to a predetermined fluid pressure;
- (b) fluid entry means for said fluid pressure responsive means to receive fluid flow from the fluid path and direct the fluid into said fluid pressure sensing means; and
- (c) fluid exit means from said fluid pressure sensing means to direct fluid from said fluid pressure sensing means back into said fluid flow path;
- (d) said fluid pressure sensing means reacts to a change of fluid pressure, within said fluid pressure sensing means, in excess of said predetermined amount to restrict and/or close-off fluid flow into said fluid pressure sensing means while permitting fluid flow from said fluid pressure sensing means.
2. The fluid pressure responsive valve of claim 1; wherein, said fluid pressure sensing means further reacts to the flow of fluid from said fluid pressure sensing means and a resulting reduction of fluid pressure therein below said predetermined amount to permit the flow of fluid into said fluid pressure sensing means.
3. The fluid pressure responsive valve of claim 1; wherein, said fluid pressure sensing means is fabricated from selected materials and so as to be capable of being in a first configuration when fluid at a fluid pressure less then said predetermined amount is to pass into, through and out from said fluid pressure sensing means and of being in a second configuration when fluid at a fluid pressure at or above said predetermined amount is to be restricted and/or cut-off from entering said fluid pressure sensing means but permitted to flow from said fluid pressure sensing means.
4. The fluid pressure responsive valve of claim 2; wherein, said first configuration of said fluid pressure sensing means is substantially an oval pillow-like configuration and said second configuration is substantially a circular configuration.
5. The fluid pressure responsive valve of claim 4; wherein, said fluid pressure sensing means includes weld means proximate respective opposite ends thereof that facilitate fabrication of same into said first, oval pillow-like, configuration while also permitting said sensing means to re-configure to said second configuration.
6. The fluid pressure responsive valve of claim of claim 4; wherein, said fluid entry means includes a fluid flow directing means extending part way into said fluid pressure sensing means so that when said fluid pressure sensing means is in said first configuration fluid may flow there into and when said fluid pressure sensing means is reconfiguring to said second configuration fluid flow into said fluid pressure sensing means is restricted and even cut-off from entering said fluid pressure sensing means.
7. The fluid pressure responsive valve of claim 6; wherein, an inside wall of said fluid pressure sensing means moves towards said fluid entry means when said fluid pressure sensing means is re-configuring to said second configuration thereof.
8. The fluid pressure responsive valve of claim 3; including,
- (a) housing means within which said fluid pressure sensing means is disposed; and
- (b) action means positioned in said housing means for co-action with said fluid pressure sensing means such that upon re-configuration of said fluid pressure sensing means from said first configuration to said second configuration said fluid pressure sensing means will co-act with said action means to cut-off and/or arrest fluid flow into said fluid pressure sensing means.
9. The pressure responsive valve of claim 8; wherein, said action means includes a pivoting lever with a first lever arm disposed to co-act with said fluid pressure sensing means as it reconfigures between said first configuration thereof and said second configuration thereof, and a second lever arm disposed for co- action with said fluid entry means to either permit or restrict and/or cut-off fluid flow therethrough.
10. The pressure responsive valve of claim 3; wherein, piston means are disposed for co-action with said fluid pressure responsive means as it reconfigures between said first configuration thereof and said second configuration thereof, said piston means including pinch means disposed for co-action with said fluid entry means to either permit or restrict and/or cut-off fluid flow therethrough.
11. The pressure responsive valve of claim 3; wherein, reaction means are disposed for co-action with said fluid pressure responsive means as it reconfigures between said first configuration thereof and said second configuration thereof, said reaction means including first and second pinch means between which said fluid entry means is disposed and which co-act with said fluid entry means to either permit or restrict and/or cut-off fluid flow therethrough.
12. The pressure responsive valve of claim 2; wherein,
- (a) said fluid sensing means includes a first sensing chamber disposed and configured to receive fluid flow from said fluid entry means and a second sensing chamber disposed and configured to receive fluid from said first chamber and permit fluid flow to exit said pressure sensing means through said fluid exit means and piston means disposed between said first sensing chamber and said second sensing chamber and co-acting therewith and responsive to an increase in fluid pressure to or above said predetermined pressure to restrict and/or cut-off fluid flow from said first sensing chamber to said second sensing chamber.
13. The pressure responsive valve of claim 12; wherein, said piston means includes a piston seat formed on wall means disposed between said first sensing chamber and said second sensing chamber.
14. The pressure responsive valve of claim 13; wherein, said piston seat and said piston are fabricated with corresponding tapered surfaces which co-act to restrict and/or cut-off fluid flow from said first sensing chamber to said second sensing chamber.
15. A fluid pressure responsive valve, for insertion into a predetermined infusate flow path, within an infusate heating device, and responsive to fluid pressure of said infusate of a predetermined amount; comprising:
- (a) deformable infusate pressure sensing means disposed and configured to define a sensing portion of said infusate flow path and responsive to a predetermined fluid pressure;
- (b) fluid entry means for said infusate pressure sensing means to receive infusate flow from the infusate flow path and direct the infusate into said infusate pressure sensing means; and
- (c) fluid exit means from said infustae pressure sensing means to direct fluid from said infusate pressure sensing means back into said infusate flow path.
16. A fluid pressure responsive valve, for insertion into a predetermined fluid-flow path, and responsive to fluid pressure of a predetermined amount; comprising:
- (a) a deformable fluid pressure sensing device for insertion into a fluid-flow path;
- (b) a fluid entry for said fluid pressure sensing device;
- (c) a fluid exit from said fluid pressure sensing device to direct fluid from said fluid pressure sensing device back into said fluid flow path;
- (d) said fluid pressure sensing device being configured and constructed to react to a change of fluid pressure, within said fluid pressure sensing device, in excess of said predetermined amount to restrict and/or close-off fluid flow into said fluid pressure sensing device while permitting fluid flow from said fluid pressure sensing device.
17. The fluid pressure responsive valve of claim 16; wherein, said fluid pressure sensing device further reacts to the flow of fluid from said fluid pressure sensing device and a resulting reduction of fluid pressure therein below said predetermined amount to permit the flow of fluid into said fluid pressure sensing device.
18. A method of restricting and/or cutting off fluid flow through a fluid flow path in response to a predetermined fluid pressure; comprising:
- (a) providing a fluid pressure sensing device for insertion into a fluid-flow path;
- (b) providing a fluid entry for said fluid pressure sensing device;
- (c) providing a fluid exit from said fluid pressure sensing device to direct fluid from said fluid pressure sensing device back into said fluid flow path;
- (d) fabricating said fluid pressure sensing device so as to react to a change of fluid pressure, within said fluid pressure sensing device, in excess of said predetermined amount to restrict and/or close-off fluid flow into said fluid pressure sensing device while permitting fluid flow from said fluid pressure sensing device.
19. The method of claim 18: including, forming said fluid pressure sensing device from a selected length of flexible tubular material and welding the ends of said selected length of tubular material together to form a deformable pressure sensing device with a pillow-like configuration.
20. The method of claim 18; including forming said pressure sensing device with a fluid entry chamber and a fluid exit chamber connected together with a fluid passageway and providing a valve operating device responsive to a change of fluid pressure within said fluid entry chamber in excess of said predetermined amount to restrict and/or close-off fluid flow from said fluid entry chamber to said fluid exit chamber while permitting fluid flow from said fluid pressure sensing device.
Type: Application
Filed: Sep 2, 2005
Publication Date: Mar 8, 2007
Applicant:
Inventors: John Landy (Billerica, MA), Michael Gildersleeve (Northborough, MA)
Application Number: 11/218,896
International Classification: F16K 31/36 (20060101);