SALA, Ezio (Via Papa Giovanni XXIIIº 14/C, Limezzane, 25065, IT)
"BLEEDER AND SAFETY VALVE IN PARTICULAR FOR RADIATORS
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C L A I M S
1. Bleeder and safety valve for hydraulic equipment, such as radiators, comprising a valve body (11) forming a chamber (12) provided with an inlet bore (13) in communication with the interior of an hydraulic system and a lateral outlet bore (14) in communication with the outside, characterised in that a valve seating (17) is provided in correspondence with the inlet bore (13) which faces towards the interior of said chamber (12); a plunger (18) is associated with said valve seating which moves between a closed and open position of said inlet bore; in said chamber a thrust member (21) is housed moving axially, and between said thrust member (21 ) and said plunger (18 at least one compressible spring (23) ) is provided to maintain the plunger in the closed position and to allow retraction into the open position of the input bore (13) only in the presence of a preset internal pressure of the controlled hydraulic system.
2. Valve according to claim 1 , in which said spring (23) is preloading adjustable by axial movement of said thrust member (21 ) to adjust and establish the pressure level at which the plunger (18) must move from the closed to the open position of the inlet bore (13).
3. Valve according to claims 1 and 2, in which said thrust member (21 ) is screwed to a threaded area (20) inside said chamber and is connected to a manoeuvring knob (22) to carry out its axial adjustment movement, or annulment, of the preload of the spring.
4. Valve according to claim 3, in which the thrust member (21 ) has a radial section or stop ring (24) designed to rest against a stop step (25) provided in the valve body (11 ) to form a maximum retraction position of said member once inserted in the body. 5. Valve according to claims 3 and 4, in which the manoeuvring knob (22) is associated in a movable manner with the thrust member (21) so as to free itself from the latte as soon as it is released after each adjustment manoeuvre to preload the spring (23), said knob and said thrust device each having engaging broaching or toothing (26,27) for coupling and uncoupling in an axial direction.
6. Valve according to claim 5, in which the manoeuvring knob (22) is associated with the thrust member (21) with the possibility of axial movement between a retracted non-operating position, in which its broaching or toothing (26) is at a distance and therefore not engaging with the broaching or toothing (27) of the thrust device, and a forward operating position, in which the broaching or toothing of the two components (21 ,22) are engaged.
7. Valve according to claims 5 and 6, in which a flexible element (28) to hold said knob in its non-operating retracted position is placed between the manoeuvring and thrust member.
8. Valve according to claim 7, in which said flexible element (28) is an integral part of the thrust member (21).
9. Valve according to any of the previous claims, in which a ring (31 ) is assembled around the valve body (11) which has an external outlet (32) for the fluid which may from the hydraulic system when the plunger is open, said outlet being in communication with the lateral output bore (14) through an annular conduit provided between said ring and said body, said ring being turnable so as to position the outlet around the valve body. |
BLEEDERAND SAFETYVALVE
Field of Invention
This invention concerns in general the field of the valve for liquid or gaseous fluids, and regards in particular the automatic bleeder and overpressure valves for hydraulic equipment, especially radiators and the like.
State of the Technique
Various realisations and configurations of bleeder valves used in thermosiphons and the like to evacuate the air which has accumulated and to release the fluid in the case of overpressure are already well-known and largely used. These valves can be either manual or automatic.
With the first type of valves the air releief can be carried out only manually by opening a normally closed valve. The second and more up-to- date type of bleeder valves automatically open and discharge, perhaps with the help of a control float, on reaching a pre-set pressure in the hydraulic equipment.
These valves however have at least the drawbacks of not guaranteeing correct functioning and protection of the hydraulic equipment even where operating pressures are relatively high, as is the case in some heating systems where damages or breakage may occur, and the lack safety devices to protect against incorrect manoeuvres.
Object and Summary of the Invention
One object of this invention is to at least avoid the abovementioned drawbacks with an automatic bleeder valve for radiators and the like:
- easily calibrated, according to requirements, to operate at different pressures,
- designed for a precise and reliable use at different pressures, in particular at relatively high operating pressures,
- sensitive to excess pressure, the peaks of which could even cause the breakdown of the hydraulic equipment it is applied to; - housing advantageously also some safety devices against accidental or mistaken manoeuvres that could inadvertently modify the operating conditions set damaging efficiency,
- having a lateral outlet which can be adjusted at an angle to direct the flow of the fluid towards the outside, furthermore - also possible to operate manually in case of an emergency and/or maintenance.
Such an object is achieved, according to the invention, with a bleeder and safety valve basically comprising a valve body forming a chamber, with an entrance bore in communication with the interior of an hydraulic device and a lateral outlet bore in communication with the outside, and where: in correspondence with the input bore is provided a valve seat facing towards the interior of said chamber; said valve seat being associated with a moveable plunger moving between a closed and open position of said entrance bore; in said chamber is housed an axially translatable thrust device; and between said thrust device and said
plunger is positioned at least one compressible spring designed to maintain the plunger in the closed position and to enable it to move back into an open position of the input bore only in the presence of a preset internal pressure of the controlled hydraulic equipment. Brief Description of the Drawings
Further details of the invention will become more evident from the following description made in reference to the enclosed indicative and not binding drawings, in which:
Fig. 1 shows an external view of the bleeder valve; and Fig. 2 shows a longitudinal section.
Detailed Description of the Invention
As shown, the bleeder valve of the invention comprises a valve body 11 that forms a chamber 12 provided with an inlet bore 13 at one end and a lateral outlet bore 14. At the inlet bore 13 end, the body has external threading 15 which enables it to be attached, with interposition of a seal 16, to hydraulic equipment to be controlled, in this case a radiator- not shown.
The inlet bore 13 is designed to communicate with the interior of said equipment and forms a valve seating 17, that is facing towards the interior of the chamber 12 and which is associated with a plunger 18 with a relative front seal 19.
Inside chamber 12 in the valve body 11 , at a distance from the inlet bore 13 and outlet bore 14, a threaded area 20 is provided to which a thrust member 21 is attached with a manoeuvre knob 22 which is found at the opposite end of said body to the one with the inlet bore 13. Thanks to
the screw coupling to the threaded area 20, said thrust member21 can be moved and be positioned axially in the body between a back and a forward position, respectively further from or nearer the plunger 18, after being turned by the manoeuvre knob 22. Between the thrust member 21 and the plunger 18 there is a compressible spring 23 designed to maintain the plunger 18 in the closed position in the valve seating 17 of the inlet bore 13 for regular operating of the system.
Starting from a zero setting, the spring 23 can be finely adjusted by axial movement of the thrust member 21 to set and/or change the working pressure of the valve as required and correspondingly the hydraulic equipment is working with. In other words, it is possible in this way to set the pressure the plunger 18 which is normally closed, must move back to automatically open the inlet bore 13 should the pressure exceed the level it was set at. By opening the inlet bore 13 this causes a flow of fluid from the radiator towards the outside through the outlet bore 14 so as to create a reduction in internal pressure to protect the integrity of the hydraulic equipment. Furthermore, for any need of bleeding of said equipment, opening of the inlet bore 13 using the plunger 18 can be also carried out manually, by using the manoeuvring knob 22 by moving the thrust member back so as to minimise or annul the action of the spring 23.
It should be pointed out that in the set described above the valve body can be made of a metal such as brass, whereas the plunger, the thrust device and the manoeuvring knob advantageously can be made of plastic. Furthermore, once the thrust member 21 has been inserted into
the valve body, it has a radial or annular stop area 24 designed to rest against a stop step 24 provided in the valve body 11 so that, once inserted into the body, said thrust member can move back as far as needed, but without sliding out of the body. In addition, the knob 22 is not, and does not remain, permanently keyed to the thrust member 21 but it frees itself from the latter as soon as it is released following each load adjustment manoeuvre of the spring 23. In fact, one part of the knob 22 has broaching or toothing 26 designed to couple in an axial direction with the broaching or toothing 27 provided on the thrust member 21.
On the other hand, the knob 22 is associated with the thrust member 21 with the possibility of axial movements between a back non- operating position, in which its broaching or toothing 26 is distant and therefore not engaging with the broaching or toothing 27 of the thrust device (top right part in Fig. 2) and a forward operating position, in which the broaching or toothing of the two components 21 , 22, are engaged (lower right part in Fig. 2).
The retracted position of the knob is normally established and maintained by a flexible element 28 which can either be inserted or even an integral part of the thrust device and formed by stop devices 29 between the two components 21 , 22. The forward position of the knob must, on the contrary be established manually in opposition to the action of said flexible element 28, so as to avoid unintentional, accidental or uncontrolled manoeuvres on the part of others and even of children, which could alter the valve settings.
In addition it should be noted that around the body of the valve, in correspondence with an annular conduit 30 in communication with the lateral outlet bore 14, is mounted a ring 31 with an external fluid discharge outlet 32 which can come from the hydraulic equipment when the plunger opens, said ring being turnable to adjust the outlet around the valve body.