WO1997032777A1 - Improvements in or relating to divers' suit valves - Google Patents

Abstract

A diver's inflation valve includes a conduit (24) located within the valve (1) and having an inlet communicating with a source of compressed air and an outlet contacting a valve member (15), the valve member being located movably within the valve and connected operably by a lever (20) to a moveable member (17) responsive to changes in water pressure, the valve including a spring (7).

Description

Improvements in or relating to divers suit valves

This invention relates to improved valves for controlling automatically the buoyancy of a diver wearing a diving suit known as inflation valves, and to valves for releasing air from a diver's suit, known as dump valves. The invention further relates to a combined inflation and dump valve.

When a diver wearing a dry diving suit descends in water the air contained in the suit is compressed by increasing water pressure. Consequently the diver loses buoyancy. However it is important for a variety of reasons for example for manoeuvring and safety that the diver should have approximately neutral buoyancy. Furthermore the air contained in the diving suit has important heat insulation properties. In order to regain neutral buoyancy air is blown from a supply of compressed air into the suit by means of a manually operated valve, situated at some conveniently accessible part in the suit.

The procedure of blowing air into the suit has to be carried out several times in the course of a descent and this can be inconvenient if the diver is required to carry out some other task, especially in an emergency situation. A purpose of the present invention is to enable a diver to maintain a neutral or other predetermined buoyancy without the need to operate the valve controls once they have been adjusted to ensure that the required buoyancy is maintained.

Accordingly in a first aspect the present invention provides an inflation valve for controlling the buoyancy of a diver wearing a diving suit comprising a conduit located within the valve and having an inlet communicating with a source of compressed air and an outlet contacting a valve member, the valve member being located movably within the valve and connected operably by a lever to a moveable member responsive to changes in water pressure, the valve including a spring, the degree of compression of which can be adjusted, the spring being arranged to affect the valve member directly or indirectly.

The valve member can be urged against the outlet of the conduit by the spring which co-operates with means for varying the pressure exerted by the spring on the valve member.

The means for varying the spring pressure can comprise a control member which can be rotated so as to compress the spring or allow the spring to extend.

The moveable member responsive to water pressure can comprise a flexible diaphragm, the central of area of which includes a rigid member which bears against the lever.

The flexible diaphragm is preferably arranged so as to be manually operable. In another embodiment of the valve the lever can be operable by contact with the member responsive to water pressure and the spring can contact the water pressure responsive member on the face opposite to that contacted by the lever.

The spring pressure in this further embodiment can be varied by means of a threaded member which contacts the spring at one end, the threaded member being located in an inner fixed cap and rotatable by means of an outer rotatable cap which engages the threaded member.

This further embodiment can include an intermediate member located between the inner and outer caps, the intermediate member being contactable by depression of the outer cap and having means to contact the water pressure responsive means.

The present invention further includes a combined inflation and dump valve including an inflation valve as described above, the valve including a water pressure responsive assembly comprising fixed and moveable portions which can either be sealingly engaged together or displaced relative to each other.

The fixed portion can comprise an annular seal which is mounted on a flexible support and the moveable portion can comprise a housing, the outer face of which contacts the lever and the other face of which is contacted by the spring.

This invention is illustrated but not restricted by the following drawings, in which Figure 1 is a side view taken in vertical section of one form of inflation valve according to the present invention. Figure 2 is also a side view taken in vertical section of a further form of inflation valve according to the present invention and Figure 3 is a side view taken in vertical section of a combined inflation and dump valve according to the present invention.

Referring to Figure 1, the valve shown generally as numeral (1) is inserted in the wall of a diving suit (2) in a position where the diver can gain ready access to knob (3) of a control member. The latter is provided with a stem (4) having a circular groove in which is located an 0 ring seal (5) . The ste terminates in a cylindrical recess (6) which houses a spring (7) . The outer wall of the recess is threaded (8) so that when the knob is rotated the spring can be either compressed or allowed to expand. In order to prevent accidental removal of the control member it is provided with a pin (9). The exposed end of spring (7) bears against valve member (10) which is located for sliding motion within the casing (11) of the valve. The valve is connected to a source (not shown) of compressed air by a nipple (12) utilising a "quick connect" coupling (not shown) . The nipple forms part of a plug connected screwably to the casing (11) of the valve and leakage of air between the plug and the casing is prevented by an 0 ring seal (13) . The plug is provided with a conduit (24) having an inlet communicating with the source of compressed air and an outlet within the valve casing which terminates in a valve head (14) having a seating (15) against which the valve member (10) is urged by spring (7) . The valve head is provided also with an 0 ring seal (16).

A flexible diaphragm (17) is secured in position by a snap-on cover (18) . The central area of the diaphragm is covered by a rigid disc (19) which bears against lever (20) . The latter pivots about position (21) and causes valve member (10) to be lifted off valve seat (15) .

In operation the diver turns knob (3) in the direction and to the extent necessary in order to provide neutral buoyancy or such other degree of negative or positive buoyancy which the diver may require. He then commences his descent. As the pressure of water acts on the flexible diaphragm (17) the latter pressures through disc (19) against lever (20) causing it to lift valve member (10) off the valve seating (15) thereby allowing air to pass round the valve member through channel (24) into chamber (22) and out through discharge annulus (23) into the diving suit.

The flow of air continues until equilibrium is reached and diaphragm (17) returns to its rest position in readiness for another cycle of operations. During a descent this cycle of operations may be repeated continuously without the need for further adjustment of the control knob. Nevertheless should the occasion require the valve can still be operated manually by pressing the diaphragm (17) . Referring to the embodiment of the invention shown in Figure 2, a valve (100) is inserted into the wall of a diving suit (not shown) in the position where the diver can gain ready access to an outer cap (102) of the valve control which will be described below.

The valve (100) is connected to a source (not shown) of compressed air by a nipple (104) and the nipple forms part of a plug which is connected screwably to a casing (106) of the valve.

The plug is provided with a conduit (108) communicating with the source of compressed air and an outlet within the valve casing in which is located a tilt valve comprising a head (110) and a seal (112) . The tilt valve is attached to a lever (114) which is contacted by the outer surface of a water pressure responsive member (116) .

The member (116) is fixed and sealed within the valve by means of an inner cap (118) which is provided with openings (120) , so that water cannot enter the divers suit, and compressed air cannot escape.

The inner cap (118) has a central threaded bore (122) in which is located a threaded head (124) and a spring (126) is located between the head (124) and the inner face of a depression formed in the member (116) .

The cap (102) is retained on the valve casing by means of an annular lip (128) on the valve casing and a corresponding annular lip (130) on the cap (102).

The cap (102) can rotate relative to the valve casing and also can be depressed relative to the valve casing.

The cap (102) is provided with two legs (132) which engage in corresponding openings (134) in the head (124) .

The cap (102) is also provided with openings (136) to allow for the free inflow of water to the water pressure responsive member (116) which will also pass through the openings (120) in the inner cap (118) .

The valve (100) is also provided with an intermediate member (138) which has a central opening (140) through which the legs (132) extend, a number of outer equispaced legs (142) which extend through openings in the inner cap (118) .

The operation of the valve shown in Figure 2 is similar to the operation of the valve as described with reference to Figure 1.

The diver turns the cap (102) in the direction and to the extent necessary in order to provide neutral buoyancy or such other degree of negative or positive buoyancy which the diver may require. It will be appreciated that rotation of the outer cap (102) causes the head (124) to rotate and depending upon the direction of rotation of the cap (102) the spring (126) will either be compressed or allowed to extend. Thus the spring pressure is varied and therefore the spring pressure acting on the water pressure responsive member (116) is varied.

As the pressure of the water acts on the diaphragm (116), the latter acts against the lever (114) causing it to operate the tilt valve and displace the head (110) from the seal (112) allowing compressed air to pass into a chamber (144) and out through openings (146) into the diver's suit.

The flow of air into the diver's suit continues until equilibrium is reached and the diaphragm (116) returns to its rest position in readiness for another cycle of operation. During a descent this cycle of operations may be repeated continuously without the need for further adjustment of the cap (102) . Nevertheless, should the occasion require, the valve can be operated manually by depression of the cap (102) in the following manner.

When the cap (102) is depressed the inner surface of the cap contacts the intermediate cap (138) and the legs (142) of the intermediate cap (138) will contact the diaphragm (116) depressing the diaphragm and therefore operating the lever (114) and the tilt valve allowing compressed air to enter the diver's suit through the outlets (146) .

It will be appreciated that in the arrangement shown in Figure 2 the spring (126) is arranged to bear indirectly upon the valve which allows compressed air to enter a diver's suit rather than directly as shown and described with reference to the arrangement shown in Figure 1.

An advantage to the arrangement shown in Figure 2 is that both the manual and automatic operations of the valve are located in the same region of the valve. The rotation of the cap (102) is used to pre-set the spring pressure whilst depression of the cap (102) provides a manual override.

It will be appreciated that the provision of manual override is required in the event that either the automatic inflation does not operate as required or that manual inflation is required when the automatic mode of operation is not available or functioning.

Referring to the arrangement shown in Figure 3, there is shown a combined inflation and dump valve in which the inflation valve includes many features common to the embodiment shown and described with reference to Figure 2. Where appropriate common references have been used regarding the components of the embodiment shown in Figures 1 and 2.

The components, construction and method of operation of the valve shown in Figure 3 is identical in many ways to that shown in the embodiment of Figure 2 apart from the construction of the water pressure responsive member (116) which allows for the valve to also function as an automatic dump valve.

In the arrangement shown in Figure 3 the member (116) is in the form of fixed and moveable portions (116a, 116b).

The fixed portion (116a) comprises a sealing member (148) which is mounted upon an annular flexible diaphragm (150) , secured in position by the cap (118) .

The construction of the moveable portion (116b) , it will be appreciated is very similar to the central portion of the member (116) shown in Figure 2, except for the provision of a knife edge seal (152) .

The operation of the valve shown in Figure 3 in the mode of an automatic inflation valve is the same as described with reference to Figure 2.

However, on ascent of the diver it will be appreciated that as the diver rises the pressure differential across the moveable portion (116b) will change so that the portion (116b) will move and lift off the seal (148) allowing air to escape from diver's suit through the openings (120) in the cap (118) between the legs (142) of the intermediate cap and out of the openings (136) in the outer cap (102) .

If the ascent is too fast or too slow the diver still retains the possibility of manually overriding the automatic dump valve function by either rotation or depression of the cap (102) as appropriate. The conditions under which a diver loses buoyancy progressively during a descent due to compression of air in his suit operate in reverse during an ascent. Thus as the diver rises the air in his suit expands as the pressure of water diminishes. As a result the speed of his ascent increases uncontrollably and this can lead to serious physiological problems, e.g. "bends" or air embolism. In the case where the suit is fitted with an inflation valve only in order to avoid this situation, diving suits are often fitted with a sensitive over-pressure valve situated as high up as possible in the suit, usually in the upper regions of the chest or arm. This over-pressure valve, often called a dump valve is adjustable manually so that the diver can set the valve to provide himself with neutral buoyancy or such other degree of buoyancy, positive or negative as he may require by controlling the release of air from his suit.

A special advantage of the inflation valves according to the present invention is that a dump valve and one of the present valves can be incorporated within a diving suit. As a result a diver can make frequent ascents and descents without the need to manipulate the valve controls once they have been provided with the correct settings. This facility is of special value when, for example, a diver is working on the legs of an oil-rig when his hands are occupied by the handling of tools.

It will be appreciated that in the case of the combined inflation and dump valve according to the invention, a separate dump valve need not be provided, both inflation and dump modes are automatic after the spring pressure has been pre-set, and both modes of operation can be manually over-ridden.

Claims

1. An inflation valve for controlling the buoyancy of a diver wearing a diving suit, comprising a conduit located within the valve and having an inlet communicating with a source of compressed air and an outlet contacting a valve member, the valve member being located movably within the valve and connected operably by a lever to a moveable member responsive to changes in water pressure, the valve including a spring, the degree of compression of which can be adjusted, the spring being arranged to affect the valve member directly or indirectly.

2. A valve as claimed in claim 1 in which the valve member is urged against the outlet of the conduit by the spring which co-operates with means for varying the pressure exerted by the spring on the valve member.

3. A valve as claimed in claim 2 in which the means for varying the spring pressure comprises a control member which can be rotated so as to compress the spring or allow the spring to extend.

4. A valve as claimed in claim 1 or claim 2, or claim 3, in which the moveable member responsive to water pressure comprises a flexible diaphragm, the central area of which includes a rigid member which bears against the lever.

5. A valve as claimed in claim 1 in which the lever is operable by contact with the member responsive to water pressure, and the spring contacts the water pressure responsive member on the face oppositive to that contacted by the lever.

6. A valve as claimed in claim 5 in which the spring pressure can be varied by means of a threaded member which contacts the spring at one end, the threaded member being located in an inner fixed cap, and rotatable by means of an outer rotatable cap which engages the threaded member.

7. A valve as claimed in claim 6 including an intermediate member located between the inner and outer caps, the intermediate member being contactable by depression of the outer cap, and having means to contact the water pressure responsive means.

ϊ. A combined inflation and dump valve including an inflation valve as claimed in any one of the preceding claims, the valve including a water pressure responsive assembly comprising fixed and moveable portions which can either be sealingly engaged together or displaced relative to each other.

). A valve as claimed in claim 8 in which the fixed portion comprises an annular seal mounted on a flexible support, and the moveable portion comprises a housing the outer face of which contacts the lever and the inner face of which is contacted by the spring.

10. A valve constructed and arranged for use and operation substantially as herein described and with reference to Figure 1, Figure 2 or Figure 3 of the accompanying drawings.

11. A diver's suit including a valve as claimed in any one of the preceding claims.