US3527248A - Apparatus for storing the state of fluidic devices - Google Patents

Description

Sept. 8,1970 6. c. WESTERN-PICK, 2

- 'APPARATUS FOR STORING THE STATE OF FLU'IDIC DEVICES Filed Jan. 14, 1969 US. Cl. 137552.5 6 Claims ABSTRACT OF THE DISCLOSURE A storage element for fluidic circuits comprises a bistable valve element which in one of its stable positions allows the passage of fluid through a duct and which by application of fluid pressure to one side is moved from the said one stable position to the other and by application of fluid pressure to the other side is returned from said other to said one stable position. Preferably the valve element is made of permanently magnetised material and is movable between two magnetisable plates so as to magnetically adhere to one plate in one end position and to the other plate in the other end position. Alternatively the valve element may be of a soft magnetic material and move between two permanently magnetised pole pieces, preferably between the north and south pole respectively of a permanently magnetised circuit.

This invention relates to fluidic devices and has for an object to provide apparatus, hereinafter called a fluidic memory device, which permits the state of a fluidic device to be stored so as to be readable by fluid flow for reinsertion into other fluidic devices. A more specific object is to provide a fluidic memory device as thus defined in which the thus stored state of the device is unaffected by temporary failure of a fluid supply.

According to the present invention the memory device comprises a bistable valve movable, under pressure supplied from a point in fluidic system to a control inlet of the device, from an A position to a B position, and restorable to the A position by application of pressure to another control inlet of the device, movement of the valve from the A position to the B position being arranged to change the condition of a fluid read passage from one to the other of an open and a closed condition, While return of the valve to A position is arranged conversely to return said read passage to said one condition.

Preferably the valve comprises a plug slidable in a cylindrical bore under pressure applied to either end of the bore, the valve plug having port means in its circumference which in one but not in the other of said A and B positions of the plug co-operates with the read passage to allow flow through the read passage. A convenient form of bistable valve comprises a valve plug which incorporates a permanent magnet and is movable in a bore of a non-magnetic body between two end plates of soft magnetic material, so that the valve plug will in its A and B positions respectively adhere by magnetic forces to one or the other end plate, a write line being provided for applying pressure to the bore at one end of the valve plug and a wipe line being arranged to communicate similarly with the bore at the other end of the valve plug,

the plug having an annular groove in its circumference at an intermediate point of its length, and a read line passage being arranged to intersect the bore in which the plug operates at a point of the bore at which in one end position of the plug the said annular groove will establish intercommunication between the two points of penetration of the read-line passage with the plug-containing bore,

United States Patent ice while in the other end position of the plug the read-line passage is blocked by the plug.

The invention can be adapted for use in a two-dimensional matrix system by arranging that a write line, hereinafter called Y-line, common to a number of memory valves, is connected to each of said valves through a port controlled by a primary valve, which is of a monostable type and which is arranged to keep the connection to said Y-line close at all times unless pressure is simultaneously applied to the primary valve through a further write line, hereinafter called X-line, which is common to said valve and one or more other valves controlled from different Y-lines, to displace the primary valve from its stable position to an operative position in which the Y-line is open, thus ensuring that the secondary valve, controlled by the Y-line, will only be moved from its A position to its B position if pressure is applied simultaneously to both the X- and Y-lines associated with the said secondary valve. This permits a number of secondary valves to be arranged in a two-dimensional matrix in which sets of valves all attached to an X-line common to such set of valves may be respectively arranged along parallel lines, which are intersected by transverse lines each corresponding to valves attached to a common Y-line.

The invention will now be described in more detail with reference to examples illustrated in the accompanying drawing, in which FIG. 1 is a sectional elevation, taken through the axis of the valve plug, of one form of bistable memory valve according to the invention and FIG. 2 is a diagrammatic perspective view illustrating part of a two-dimensional matrix with valves of the kind illustrated in FIG. 1 constituting the secondary valves, and monostable spring-loaded valves constituting the primary valves.

Referring now first to FIG. 1, the memory device comprises a slab 1 of non-magnetic material, which may be a suitable plastics material, and which is perforated by a number of parallel bores 2, of which only one is shown. In each bore 2. a plug 3 of high-coercivity or hard magnetic material, for example hard carbon steel, is arranged for longitudinal sliding movement. The plug 3' is of the spool type, having two large-diameter portions or lands 4 which are spaced from each other by a small-diameter portion 5 so as to form a circumferential annular port or groove 6 surrounding the small-diameter portion 5 between the two end portions or lands 4. The slab 1 is sandwiched between two plates 7 and 8 of loW-coercivity or sof magnetisable material, for example of mild steel, and the plug 3 is permanently magnetised in its longitudinal direction so that when in contact with either of the plates 7 and :8 it will be retained in that position by magnetic forces. Each of the plates 7 and 8 is perforated at the end of each bore 2, as shown at 9 and 10 respectively, and these perforations are continued by pressurising passages 11 and 12 respectively, which in the illustrated embodiment are provided in covering layers 13 and 14 applied respectively to the outer side of each of the plates 7 and 8; furthermore two aligned passages 15, 16 are provided for each bore in the slab 1, and penetrate the bore '2 at two diametrically arranged points, so that, when the plug 3 is in the illustrated position, which may be referred to as the B position, and in which the plug is applied to the magnetic plate 8 shown in the drawing at the lower end of the bore, the two passages 15 and 16 are in free communication with each other through the annular groove or port 6 of the plug 3. When the plug is moved from this B position into the A position, in which it is in contact with the other magnetic plate 7, communication between the passages .15 and 16 is cut by one of the lands 4 of the valve plug 3.

In order to use the valve plug as a memory element, the line 11 may be used as a write line and the line 12 as a wipe line, which latter is preferably common to all the plugs 3 of a matrix. It will be readily appreciated that when a wipe pulse of pressure is applied to line 12, all the plugs 3 of the matrix which are in the illustrated B position will move to their respective A position in which the plug is in contact with the magnetic plate 7 shown at the upper plate in the drawing, cutting communication between the read- line passages 15 and 16, while these plugs already in their A position will be held in that position. When a write pulse is then applied to an individual plug 3 by application of pressure to its write line 11, this plug will move from its A position to its illustrated B position, in which it will stay, due to its magnetic adhesion to the plate 8, until a further wipe pulse is applied through line 12. The existence of this B position state can be non-destructively ascertained at any time by applying pressure to one end 15 of the read line, which in this case will cause a flow through the read lines 15, 16. This flow may itself be utilised in a fluidic apparatus.

FIG. 2 illustrates an arrangement in which, in order to allow a relatively large number of memory-valve plugs 3 to be controlled by a relatively small number of control lines, the operation of each valve plug is made dependent on the simultaneous presence of a pulse in both an X-line and a Y-line, in a manner similar to that commonly employed in electro-magnetic memory matrices of electronic computers. In order to achieve this, each valve plug 3 is operated as a secondary valve which is operable by the application of pressure to its write line 11, which may be referred to as a Y-line and be common to a number of memory valves, only when a primary valve which is also associated with the individual memory valve and may be common to it and a number of other memory valves respectively included in different Y-lines, and which is normally held in its closed position by a spring 19, is opened by the simultaneous application of pressure to its valve plug 18 from an X-line 20.

It will be readily appreciated that the invention is not limited to all the details of the examples described with reference to the accompanying drawing. Thus while the primary valves in FIG. 2 have been described as rendered monostable by the use of a spring, the primary valves may alternatively be magnetically biased, in which case their construction may be similar to that of the valves described with reference to FIG. 1, except that the magnetic plate 8, which in the valve of FIG. 1 tends to maintain the valve in its operative position, is omitted or rendered inoperative by an aperture of sufficient magnitude. Conversely the memory valves may be rendered bistable in a manner different from that described with reference to FIG. 1, one possible modification consisting in the use of soft magnetic plugs in co-operation with suitably polarised end plates or end members. Furthermore the primary valves may be replaced by the action of, for example, a purely fluidic AND gate.

What I claim is:

1. A fluidic memory device which comprises a read passage, a valve movable from an A position to a B position and vice versa thereby changing the condition of said read passage from one to the other of a closed and an open position, the device having a first and a second fluidpressure inlet so arranged that application of pressure to said first or said second inlet acts to move the valve respectively from the A position to the B position or from the B position to the A position, and bias means continuously operative, independently of fluid action, to exert, When the valve is in the A position, a bias force opposing movement of the valve towards the B position, and when the valve is in the B position, a bias force opposing movement of the valve towards the A position.

2. A fluidic memory device as claimed in claim 1, wherein the bias means include a permanently energised magnetic circuit so arranged as to have maxima of its magnetic flux at each of the A and B positions of the valve.

3. A device as claimed in claim 1, comprising a body having a cylindrical bore closed at each end and two readpassage ports communicating with said cylindrical bore between the two ends thereof, the read passage being made in two parts respectively terminating at said ports, the valve being constructed as a plug slidable in said cylindrical bore, said first and second inlet being connected to the two ends of said bore respectively, and the valve plug having port means in its circumference which in one, but not in the other, of said A and B positions of the plug co-operate with said read-passage ports to allow flow through the read passage.

4. A device as claimed in claim 1, which includes a body of non-magnetic material having a bore and two end plates of soft magnetic material closing the two ends of the bore, the valve being constituted by a valve plug which incorporates a permanent magnet so that the valve plug is movable along the bore between two end positions respectively constituting the A and B positions, in each of which the plug will adhere by magnetic forces to one or the other end plate, the device further including a write line extending from the first inlet to one end of the bore and a wipe line extending from said second inlet to the other end of the bore, the plug having an annular groove in its circumference at an intermediate point of its length, and a read-line which includes a passage so arranged in the non-magnetic body as to intersect the bore at a point at which in one end position of the plug said annular groove will establish continuity of said read-line passage while in the other end position of the plug the read-line passage is blocked by the plug.

5. A fluidic memory system comprising a plurality of devices each as claimed in claim 1, a plurality of write lines, hereinafter called Y-lines, each common to the valves of a number of said devices, a plurality of primary valves respectively associated with each said device and each having a port which when open connects said write line to the valve of the device in question, each primary valve being of such monostable construction as to be biased to keep the connection to said Y-line closed and operable by fluid pressure against such bias to open such connection, a plurality of further write lines, hereinafter called X-lines, each common to two or more valves controlled from different Y-lines and connected to the primary valve associated with each of the said two or more valves in such manner as to displace the primary valve from its stable position when pressure is applied to said X-line.

6. A fluidic memory system comprising a plurality of devices, each as claimed in claim 1, a plurality of AND gates each associated with one of the devices, a plurality of write-lines hereinafter called Y-lines, each common to a number of memory devices and connected to each of said devices through one of said AND gates, and a number of further write-lines, hereinafter X-lines, each common to two or more valves controlled from different Y-lines and connected to the AND gate associated with said valves, each AND gate being arranged to render fluid supply to its associated Y-line operative upon the valve of the device when and only when the X-line associated with the same AND gate is supplied with fluid at the same tlme.

References Cited UNITED STATES PATENTS 3,057,551 10/1962 Etter 251-367 XR HENRY T. KLINKSIEK, Primary Examiner US. Cl. X.R. 137-608; 251-63, 65, 367

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