Patent Publication Number: US-2021171169-A1

Title: Device for detecting the pressure of compressed gas cylinders in breathing apparatuses for scuba diving

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to PCT International Application No. PCT/IB2019/054171 filed on May 21, 2019, which application claims priority to Italian Patent Application No. 102018000005711 filed on May 25, 2018, the disclosures of which are expressly incorporated herein by reference. 
     STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT 
     Not applicable. 
     DESCRIPTION 
     Field of the invention 
     The present invention refers to the sector of instruments for underwater use; in particular, the present invention refers to a device for detecting the pressure of compressed gas cylinders in breathing apparatuses for scuba diving. 
     State of the Art 
     The devices currently on the market for detecting the pressure of compressed gas cylinders for scuba diving are subject to compromises in terms of both maintenance and size. 
     To obtain dimensionally acceptable products, small sensors are required which are less precise and/or more expensive than larger sensors; alternatively, in order to use larger sized sensors, housings are required for the sensors, but this makes product maintenance difficult. 
     The technical problem encountered therefore pertains to the use of sensors with a relatively large diameter to obtain more precise cylinder pressure readings, without this affecting housing and maintenance. 
     The Applicant of the present patent application has ascertained the need to produce an efficient device for detecting the pressure of gas cylinders for underwater use. 
     SUMMARY OF INVENTION 
     In a first aspect, the present invention refers to a detection device for detecting the pressure of compressed gas cylinders in breathing apparatuses for scuba diving, like the one indicated in claim  1 . 
     The present invention stems from the general consideration that the technical problem highlighted above can be effectively and reliably solved by means of a watertight device for underwater use that comprises: 
     a main body internally comprising a housing to house at least one pressure sensor for detecting the pressure of a gas cylinder connected to said device; 
     an interface element that connects said pressure sensor to a hose for connection to said cylinder; 
     at least one seal element arranged between said interface element and said pressure sensor, 
     wherein said interface element is removably fixed to said main body by means of at least one fixing element which is arranged at the housing that houses said pressure sensor. 
     In this way, due to the configuration of the device for underwater use of the present invention, it is possible to use pressure sensors having a large diameter, high precision and low cost in a device with extremely compact external dimensions, maintaining the characteristics of easy maintenance. 
     Furthermore, the watertight elements can be fully replaced from outside of the device without affecting the seals of the rest of the device. 
     In fact, it is sufficient to remove the fixing element that fixes the interface element to the main body of the device of the present invention to access the seal elements to be replaced located between the interface element and the pressure sensor. 
     In a preferred embodiment, said housing for the pressure sensor is substantially cylindrical-shaped, hollow inside, and is provided with a substantially circular shaped lateral opening facing said interface. 
     According to a preferred embodiment, said pressure sensor is substantially cylindrical-shaped with the diameter of the base surfaces slightly smaller than the diameter of said lateral opening of the housing so that the pressure sensor can be inserted, through said lateral opening, to fit tightly inside the housing, following the circular contours thereof. 
     In this way, the space inside the housing is practically completely occupied by the pressure sensor, which can therefore be chosen with dimensions such as to adapt to the large space available in said housing. 
     According to a preferred embodiment, said at least one fixing element is removably fixed to said housing perpendicular to the axis of the pressure sensor. 
     According to a preferred embodiment, a first and a second fixing element are present arranged diametrically opposite relative to the circular surface of said pressure sensor housing, each of said first and second fixing elements being arranged perpendicular to the axis of the pressure sensor. 
     This improves fixing of the interface element to the main body of the device of the present invention. 
     According to a preferred embodiment, the device of the present invention further comprises a compartment for at least one battery to power said device. 
     According to a preferred embodiment, the device of the present invention further comprises a closing element for closing said battery compartment. 
     In this way, the battery that powers the device is in a protected watertight compartment. 
     According to a preferred embodiment, the device of the present invention further comprises a central unit able to receive the pressure values detected by said pressure sensor. 
     According to a preferred embodiment, said central unit is arranged inside said main body. 
     According to a preferred embodiment, the device of the present invention further comprises a display to make the information detected by said pressure sensor, relative to the pressure of the gas cylinder connected to the device, visible to the user. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Further characteristics and advantages of the present invention will become clearer from the examination of the following detailed description of a preferred but not exclusive embodiment, illustrated by non-limiting indicative purposes, with the support of the attached drawings, in which: 
         FIG. 1  is an exploded isometric view of an embodiment of the device of the present invention; 
         FIG. 2  is a sectional view of the device of  FIG. 1 ; 
         FIG. 3  is a lateral view of the device of  FIG. 1 . 
     
    
    
     DETAILED DISCLOSURE 
     The following detailed disclosure refers to a particular embodiment shown in  FIGS. 1-3 . 
     With reference to  FIGS. 1-3  in particular, a watertight device  1  for underwater use provided with a main body  11  is described. The device  1  is powered in a stable manner by a battery  6 , housed in a compartment  5  inside the main body  11 , the compartment  5  being closed by a plug  4 . 
     The main body  11  internally comprises a cylindrical-shaped housing  12 , hollow inside, which has a circular-shaped lateral opening  13 . The housing  12  has dimensions such as to be able to internally house a cylindrical-shaped piezoelectric pressure sensor  8 , wherein the diameter of its base surfaces is slightly smaller than the diameter of the lateral opening  13  of the housing  12 . Said dimensions allow the pressure sensor  8  to be passed through the lateral opening  13  and to be inserted to fit tightly in the housing  12 , following the circular contours thereof, thus optimizing the space available for the sensor  8 . 
     The pressure sensor  8  is able to detect the pressure of a gas cylinder for underwater use positioned on the outside of the device  1  of the present invention (not shown in the figures) to which the pressure sensor  8  is connected by means of an interface element  7  located in an intermediate position between the sensor  8  and a hose  3  for connection to the cylinder. Between the sensor  8  and the interface element  7 , gasket elements  10  are also provided which ensure that the sensor  8  is watertight. 
     The interface element  7  is removably fixed to the main body  11  of the device  1  of the present invention by means of two fixing elements  9  arranged at the housing  12  which houses the sensor  8 . The two fixing elements  9  are arranged diametrically opposite relative to the circular surface of the opening  13  of the housing  12  of the pressure sensor  8 , each of them being arranged perpendicular to the axis of the pressure sensor  8 . 
     The pressure sensor  8  is able to transmit the detected gas cylinder pressure values to a central unit arranged inside the main body  11 . Said values detected by the sensor are then displayed to the user via the display  2  positioned on the outside of the main body  11 , activated by the central unit. 
     The device of the present invention therefore allows optimization of the space dedicated to the pressure sensor  8  housed inside the housing  12 ; the sensor  8  can therefore have sufficiently large dimensions, thus guaranteeing more precise gas cylinder pressure readings. 
     Furthermore, due to the arrangement of the fixing elements  9  which fix the interface element  7  to the main body  11  of the device  1 , it is possible to carry out replacement, in a practical effective manner, of the elements  10  which guarantee the watertight seal of the device. In fact, it is possible to simply remove only the fixing elements  9 , leaving unchanged and watertight the remaining portion of the main body  11  of the device  1  housing the other functional elements of the device  1 , for example the central unit, the battery  6 , etc. 
     Naturally, many modifications and variations of the preferred embodiments described will be evident to persons skilled in the art while remaining within the scope of the invention. 
     Therefore, the present invention is not limited to the preferred embodiment described, illustrated only as a non-limiting example, but is defined by the following claims.