IMPROVEMENTS IN AND RELATING TO AN AIR SUPPLY VALVE

Abstract: The invention refers to an improvement in and relating to an air supply valve (1), comprising a shutter housing (2) with an adjustable shutter blade (3) fitted inside which from a first completely closed position is turnable through a predetermined angle to an open position. The shutter blade (3) is on one hand manually turnable from the said open position further through another predetermined angle to a second completely closed position and is on the other automatically adjustable according to the outdoor temperature during turning of the shutter blade (3) from the first closed position to said open position, using a thermostat unit (4) that is fitted to the shutter blade (3).

Description: Improvements in and relating to an air supply valve The present invention refers to an air supply valve comprising a shutter housing with an adjustable shutter blade fitted inside, which from a first completely closed position can be turned through a predetermined angle to an open position. Inlet air supply valves of this type are common for controlling air entering a building and are either manually or automatically adjustable, depending on the outdoor air temperature. At colder temperatures, for example -10°C, the valves are usually closed. At temperatures above -10°C, the valve opens either manually or automatically. The problems with the known valves are that those valves which are adjusted automatically cannot at the same time be be adjusted manually for closing in a simple manner, if it should become necessary. Further, the valves which are manually adjustable are not suitable for automatic adjustment . The object with the present invention is to solve the problems with known air supply valves, and to provide an inlet air supply valve which can be controlled both manually and automatically. Another object with the invention is that an air supply valve according to the invention, originally intended for manual adjustment, can easily be complemented with a thermostat unit, which then enables both automatic and manual adjustment of the valve. The characterizing features of the invention are stated in the following claims. Due to the invention, an air supply valve has been provided which satisfies its purpose in an excellent manner, as well as it is both simple and inexpensive to manufacture. The shutter blade in the air supply valve according to the invention is provided turnable around a shaft in the centre of the shutter housing. In a first position, the shutter blade is completely closed, and after turning the same through a predetermined angle, the shutter blade is in a maximum open position. Due to the air supply valve being complemented with a thermostat unit, this first adjustment of the shutter blade can be achieved automatically. From the open position, the shutter blade can be turned further manually through a predetermined angle to the fully closed position without affecting the thermostat control. The manual control of the shutter blade is made by means of gears and a self-cleaning gear rack, which prevents debris, grease and similar, which otherwise easily gets caught in the valve, do not hamper the function of the adjustment of the shutter blade. The invention is further described below with the aid of a preferred embodiment example and with reference to the accompanying drawings, where Fig. 1 shows a schematic perspective view diagonally from the rear of an air supply valve according to the invention having a thermostat unit fitted to the shutter blade, Fig. 2 shows the valve illustrated in Fig. 1 in a schematic perspective view from the opposite direction, Fig. 3 shows an exploded view of the air supply valve according to Fig. 1 and 2, which indicates how the various included parts are fitted in relation to each other, and Fig. 4 shows a schematic exploded view in perspective seen from the opposite direction than what is the case in Fig. 3 with the various parts dismantled and then especially, the thermostat unit.' As evident by the drawings, the preferred embodiment example consists of an air supply valve 1 according to the present invention, and a shutter housing 2 with a shutter blade 3 that can be turned fitted inside the housing. The valve 1 is according to the preferred example designed so that the shutter blade 3 is biased with a torsion spring, not shown on the drawing, in its closed, first position shown in Fig. 1 and 2. From this first, completely closed position, the shutter blade 3 can be turned through a predetermined angle to an open position, using a thermostat unit 4 fitted to the shutter blade 3. From the open position, to which the shutter blade 3 has been turned by means of the thermostat unit 4, if desired, the shutter blade 3 can then be closed manually by turning it further through a predetermined angle to a second fully closed position. The manual control of the shutter blade 3 is achieved via a lever 19 with at least one gear 6 ; 7 acting on a gear rack 5, which in turn actuates turning of the shutter blade 3. The gear rack 5, in the shown example, consists of a plate 8 with rectangularly formed slots 9 for engagement with said gears 6 , 1 . Due to this design of gear rack 5, it becomes self- cleaning from grease, debris and similar. For positioning of the thermostat unit 4, the shutter blade " 3 has a centrally located recess 10, in which the position of the thermostat unit 4 can be secured with a simple hand movement. The output torsion shaft 11 of the thermostat unit 4 moves in relation to the influence of an outdoor temperature sensor 12, and the torsion shaft 11 in turn actuates the adjustment of the shutter blade 3. The ' thermostat unit 4 consists of, in addition to the sensor 12, a guide sleeve 16 with a covering torsion spring 17 and a turning device 13, which shows two opposing, diagonally cut steps 14, 15, which transfer the linear movements of the sensor 12 to a turning motion, and the parts are held together by a clamp element 20. The turning motion is thus transferred from the turning device 13 to the underlying shutter housing 2 for turning of the shutter blade 3. The gear wheel 6 located under the thermostat unit 4 shows a number of sequentially arranged gear teeth 18 only mainly along half its periphery corresponding to the turning of the shutter blade, which is manual. The air supply valve according to the invention 1 functions as follows. In cases where the shutter blade 3 has been fitted with a thermostat unit 4, there is an automatic adjustment the first 70-90° according to the outdoor temperature during the first opening phase of the shutter blade 3 from closed to open position. After this, the shutter blade 3 can be closed manually by turning through another predetermined angle to approximately 140-180°. In case a thermostat unit 4 has not yet been fitted to the shutter blade 3, opening and closing of the valve 1 is performed only manually, and then in a range which covers the shutter blade 3 second opening phase, from open to closed, and back.

Claims: Claims 1. Improvements in and relating to an air supply valve comprising a shutter housing (2) including an adjustable shutter blade (3) fitted inside which from a first completely closed position is turnable through a predetermined angle to an open position, characterized' in that the shutter blade (3) on one hand is manually turnable from said open position further through another predetermined angle to a second completely closed position and on the other is automatically adjustable according to the outdoor temperature during turning of the shutter blade (3) from said first closed position to said open position using a thermostat unit (4) fitted to the shutter blade (3) , which comprises a sensor (12) , the linear movement of which acts on two diagonally cut steps (14, 15) on a turning device (13) located in the thermostat unit (4), and in turn, said turning device transfers its turning movement to the shutter blade (3) via the shutter housing (2) and an output torsion shaft (11) of the thermostate unit (4) , during its automatic adjustment. 2. Air supply valve according to claim 1, characterized in the shutter blade (3) being biased by spring force in the direction towards its closed position. 3. Air supply valve according to claim 1, characterized in that the shutter blade (3) manual control being achieved through at least one gear wheel (6; 7) acting on a gear rack (5) which in turn actuates the turning of the shutter blade (3) . 4. Air supply valve according to claim 3, characterized in that the gear rack (5) consists of a plate (8) having rectangular slots (9) for engagement with the proximal gear wheel (7) , through which the gear rack is self-cleaning. 5. Air supply valve according to claim 1, characterized in that the shutter blade (3) having a centrally located recess (10) for co-operation wit ' h said complementary thermostat unit (4) . 6. Air supply valve according to claim 1, characterized in that in cases where the shutter blade (3) has been fitted with a thermostat unit (4) , there is automatic adjustment the first 70-90° according to the outdoor temperature during the shutter blade (3) first opening phase from closed to open position, after which closing of the shutter blade (3) is performed manually by turning through another predetermined angle to 140-180°. 7. Air supply valve according to any of the preceding claims, characterized in that there is a gear wheel (6) beneath the thermostate unit (4) comprising gear teeth (18) sequentially arranged only mainly along half its periphery, which is the circumference corresponding to the distance of the movement of the shutter blade (3) which is controlled manually.

Inventors: WIDEN GOERAN, WIDEN, GOERAN
Applicants: PAX ELECTRO PROD AB, WIDEN GOERAN, PAX ELECTRO PRODUCTS AB, WIDEN, GOERAN
Application year: 1999
Main classification: F24F11
IPC codes: F16K1, F16K31, F24F11, F24F13