GB1413788A - Control unit for supplying fluid medium to a dental instrument - Google Patents

Abstract

1413788 Valves KALTENBACH & VOIGT 1 Aug 1974 [6 Aug 1973] 34093/74 Heading F2V A control unit comprises a control block 2 for supplying fluid to a dental instrument, a further block 1 secured to block 2, passages 6, 7, 8, passing through the blocks for supplying fluid, a diaphragm 12 disposed in sealing relationship between the blocks, a control chamber 13 in block 1 adapted to supply pressure to control movement of the diaphragm, and a valve 17 in block 2, responsive to movement of the diaphragm so as to control the supply of fluid through the passages. Further blocks 3, 4 are secured to blocks 1, 2, and passages 6, 7, 8, carry air for driving the dental instruments, cooling water for a spray, and cooling air for cooling the instrument motors respectively. Diaphragms are provided between each pair of blocks, and passage discharge branches 6<SP>111</SP>, 7<SP>111</SP>, 8<SP>111</SP> are provided in each block 1, 2. Air is supplied to chamber 13 in blocks 4, 1, from a source 26, Fig. 4, through a passage 14. In operation, a dental instrument is lifted from a holder 28 so that a valve 27 is opened and chambers 13 are relieved of pressure. Air flows through passage 6, lifts a spring-urged valve 17 from its seat 16 and flows into passage 6<SP>111</SP>, where it moves a piston 24 to operate a switch 23 which controls the dental instrument. The passages 7<SP>111</SP>, 8<SP>111</SP> are similarly supplied with fluid pressure. When the instrument is placed on to holder 28, valve 27 is closed and air is supplied to chambers 13 and acts on diaphragms 12 so as to close valves 17 in the passages 61, 7<SP>1</SP>, 8<SP>1</SP>.