US3461911A

US3461911A - Magnetic latch for magnetically operated valve

Info

Publication number: US3461911A
Authority: US
Inventors: Zbigniew J Janczur
Original assignee: MAROTTA VALVE CO
Current assignee: MAROTTA VALVE CO
Priority date: 1966-02-15
Filing date: 1966-02-15
Publication date: 1969-08-19
Anticipated expiration: 1986-08-19

Description

Aug. 19, 1969 z..|. JANCZUR 3.461,911

MAGNETIC LATCH FOR MAGNETICALLY OPERATED VALVE Filed Feb. 15, 1966 l y I F l, 7l 4 lo 58 6 IG 4465/2- 3o 2434 6a ,f l ,04 50 I4 'A (338 56 f" 85 9699 75 48.-.. ya 4 50.; 98

56 7 l 6 6416 48 2a 26 74 2C l//l l /l/l/l/'rl/8 o /06 I6 998 909 N2 .5 f2 24 ,ff /34 f '04 FIG. 3. 44 '06 63 3 n y99 9o '02 24,v| 30 74 2a' 34 I FIG. 5. 301

\\\` aNveNToR United States Patent O U.s. c1. 137-6255 13 Claims ABSTRACT on THE DISCLOSURE This magnetically operated valve has a latch for holding it in position to which it is moved by a magnetic actuator. A subsequent actuation with polarity of the electromagnetic actuator reversed causes the latch to release so that the valve returns to its original position. If the valve is originally actuated by the reverse current flow, it operates without the latch becoming effective. The latch, which is preferably a cam, is movable between operative and inoperative positions independently of the movement of the valve, and no rotation of the valve or valve stem is necessary, as in the prior art.

BRIEF DESCRIPTION OF THE INVENTION This invention relates to magnetically actuated valves and more especially to apparatus for locking or latehing a valve in one position.

It is one object of the invention to provide an improved construction for a magnetically actuated valve, which moves between open and closed positions, with means for holding the valve in one of its positions. 'Ihe invention is especially concerned with valves which are moved into one position byV energizing a magnetic coil and which require that the coil remain energized in order to maintain the valve in the position to which the coil has moved it. In cases where the coil is energized by current from a battery, this continued use of current is objectionable.

Another object of the invention is to provide a latch or lock which operates automatically to hold the valve in the position to which it is moved by the energizing of the magnetic coil. The supply of energy to the coil can then Vbe turned oi, and the valve will remain in the position to which the coil has moved it. The invention is applicable to shut-off valves and also to three-way valves, pilot valves or any valve which is movable between two positions and which is moved into at least one of these positions by l,the energizing of a magnetic coil.

opposite polarity.

Other objects, features and advantages of the invention will appear or be pointed out as the description proceeds.

Patented Aug. 19, 1969 BRIEF DESCRIPTION OF THE DRAWINGS In the drawing, forminga part hereof, in which like reference characters indicate corresponding parts in all the views: f

FIGURE l is a sectional view showing a magnetically actuated three-way valve with locking means for holding it in the position to which it is moved by energizing its magnetic coil;

FIGURE 2 is a sectional view of the construction shown in FIGURE l but with the valve stem shifted to one end of its stroke and the locking means in operative position;

FIGURE 3 is a view similar to FIGURE 2 but showing the positions of parts at another time of the cycle of operation of the invention;

FIGURE 4 is a fragmentary sectional view of a modied form of the invention; and

FIGURE 5 is a sectional view on the line 5--5 of FIGURE 4.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGURE l shows a valve assembly 10 including a housing 12 enclosing a valve chamber 14 in which there is a valve element 16. The valve element illustrated has a stem 18 at one end and another stem 20 at its other end, in position to contact with an operating stem 22 of an electromagnetic actuator Z4.

The actuator 24 includes a sleeve 26 in which the operating stem 22 is threaded, and includes also a ferrous metal casing 28 which encloses an electromagnetic coil 30, and in which the sleeve 26 slides axially.

A disc armature 34 is connected to the end of the sleeve 26; and this armature 34 is attracted to the ferrous metal casing 28 and the coil [30 Whenever the coil 30l iis energized.

The valve assembly illustrated is a three-way valve having two

seats

38 and 40 at opposite ends of a middle portion of the valve chamber 14. A port 44 opens into the middle portion of the valve chamber, and

other ports

46 and 48 open into

end portions

50 and 52 of the valve chamber 14 beyond the

seats

38 and 40, respectively. The Valve element 16 is urged into Contact with the seat 40 by a spring 56 compressed between a washer 58, that fits over one end of the stem 18, and a plug 60 which screws into a bushing 62.

'Ihe plug 60 is adjustable along the threads in the bushing 62 to change the force of the spring 56. The bushing 62 screws into a counterbore in the housing 12 and clamps in assembled relation the

seats

38 and 40, and

spacers

63, 64 and 65 which hold the seats in place; and this bushing 62 holds the assembled seats and spacers clamped against a shoulder 66 at one end of the valve chamber 14.

The valve element 16 is moved into contact with the seat 38, against the force of the spring 56, by the force of the electromagnetic actuator 24 attracting the disc armature 34. The actuator 24 is contained in a shell housling 68 which comprises a part of the valve assembly 10 to the disc armature 34 and the armature and support assembly are attached to the stern 22 by a nut 75 threaded over the end of the stem 22. The connection can be made in other Ways, so long as the armature and support move as a unit With the stem 22. Thus the position of the support 74 corresponds to the position of the valve element in the valve chamber.

The support 74 is part of the locking means of this invention and it provides bearings at opposite ends of an axle 88. There is a camV 90 on the axle 88; and this cam 90 has a high portion 92 which moves into a position adjacent to an end of a stop screw 93 when the cam 90 moves angularly about the axis of its axle 88 as shown in FIGURE 2.

FIGURE 1 shows the high portion 92 of the cam out of line with the operating stem 22, and the locking means is thus in inoperative position. FIGURE 2 shows the parts in the positions occupied when the coil has been energized and the armature 34 has moved the operating stern 22 far enough to close the valve element in one direction.

In the illustrated embodiment of the invention, the cam 90 is made of non-magnetic material and it is operated by a polarized element consisting of a permanent magnet 96 attached to the cam 90 and with the poles of the magnet 96 projecting beyond the cam 90. When the electromagnetic coil 38 is energized by current of one polarity, the pole 99 of the magnet 96, having opposite polarity to that of the armature end of the coil 30, moves the cam 90 angularly from the position shown in FIGURE l to the position shown in FIGURE 2. When the coil is energized by current ot opposite polarity, however, the pole 98 is repelled by the coil 38, and a pole 99 at the opposite end of the magnet 96 is attracted by the coil 30 so that the cam 90 swings back into the position shown in FIGURE l.

FIGURE 2 shows a clearance 100 between the cam 90 and the stop screw 93. This clearance is exaggerated in the drawing for better illustration. When the magnetic coil is de-energized, the operating stem 22, armature 34 and support 74 move back until the cam 90 strikes the stop screw 93, but this movement is not suicient to shift the valve element 16 out of contact with the valve seat 38 (FIGURE 2) to which it is moved by energizing of the coil 24. The closing of the clearance 100 in FIG- URE 2. does decrease the pressure of the valve element against its seat but there is suicient resilience in the seat, or in the operating parts, so that the force of the magnetic pull can be released sufliciently to let the cam 90 move into contact with the stop screw 93 without reducing the pressure of the valve element against its seat sufliciently to cause leakage of the valve.

When the valve is to be shifted back into its other position, the coil 24 is energized with current of opposite polarity, as previously explained, and this moves the cam 90 away from the stop screw 93 by the amount of the clearance 100 so that the cam 90 is relieved of any friction with the stop screw and is free to turn back into its position shown in FIGURE l, as already explained. When the coil 24 is de-energized and the parts are in the positions shown in FIGURE 1, the cam 90 cannot be turned accidentally into position to lock the valve element open toward the left because as long as the coil 24 is de-energized and the armature 34 is spaced from the coil, the high part 92 of the cam 90 will strike against the side of the screw 93 and the high part 92 cannot move into line with the screw 93.

Under some circumstances, it is desirable to operate the valve without the locking feature, and this can be done by using only current of the polarity that unlocks the valve.

There is a flanged bushing 102 extending through an end Wall 104 of the shell housing 63. This bushing -102 has its flange against the inside of the end wall 104 and has a nut 106 screwed over threads on the outside of the bushing to clamp the end Wall 104 between the bushing ange and the nut 106. There are threadsv 108 insidethe bushing 102, and the stop screw 93 iits the threads 108 and is adjustable to obtain optimum clearance 100.

FIGURES 4 and 5 show a modified form of the invention. Parts corresponding to those of the construction shown in FIGURES l-3 are indicated by the same reference character with a prime appended. An armature 34 is attached to a sleeve.26 of an actuator 24 which is the same in principle as the construction shown in the `other views, though the armature 34 is connected to the Sleeve 26 by a riveted connection 120 instead of a pressed connection and the sleeve 26 slides in the casing 28 as a. bearing.

The cam mechanism shown in FIGURES 4 and 5 is quite different, however, from that of the construction shown in FIGURES 1-3. A housing 122, which ycorre'- sponds to the housing 68 of the construction of FIGURES 1-3, encloses the actuator 24. A plug 124 screws into an end wall of the housing 122 and this plug 124 has a counterbore 126 at its inner end in substantial alignment with the stern 22'.

An axle 130 extends across the counterbore 126 and lits into aligned openings 132 with a press fit. A cam 134 is supported on the axle 130 by anti-friction bearings 136. The cam 134 has a hub 140 at one end and there isa disk magnet 142 mounted on the hub 140 so as to form an integral assembly with the cam 134.

The cam 134 is preferably circular except for a recess 146 formed in the circumference of the cam along a section of the circumference slightly greater than the diameter of the stern 22. When the cam 134- is in the position shown in FIGURES 4 and 5, the recess 146 is in line with the stem 22 and this recess is deep enough so as not to interfere with the freedom of movement of the stem 22.

The magnetic disk 142 has a north pole at one side of the disk and a south pole at a diametrically opposite location on the other side of the disk as indicated by the legends N and S in the drawing. When the actuator 24 is energized by current of a polarity to make the righthand end of the actuator a south pole, the armature 34 is attracted to the coil of the actuator 24' and the magnetic disk 142 is turned into position to orient the cam 134, as shown in FIGURES 4 and 5.

When the polarity of the current supplied to the actuator 24 is reversed, so that the right-hand end of the actuator becomes a north pole, the north pole of the magnetic disk 142 is repelled and the south pole is attracted to the actuator 24', thus rotating the cam 134 through or -whatever lesser angle it can turn through as the result of mechanical stops which may be provided on the plug 124. Such stops may be provided for the cam at both ends of its travel.

It will be understood that the type of cam shown in FIGURES 4 and 5 can be replaced With a cam having a progressively variable radius, or with a cam of the type shown in FIGURES 1-3. The construction shown in FIGURE 5 has the advantage that the carn and the supporting means for the cam do not reciprocate with the stem 22 and the mass of the moving parts is thus reduced so that faster response of the actuator can be obtained, or similar response with an actuator of smaller size and weight.

The preferred embodiment of the invention has been illustrated and described, but changes and modifications can be made and some features can be used in different combinations without departing from the invention as defined in the claims.

What is claimed is: l

1. In a magnetically actuated valve, a housing enclosing a valve chamber, a seat in the chamber, a valve element movable toward and from the seat to shift the valve element between closed and open positions, stem means that move as a unit with the valve element, a magnetic coil that moves the stem means in response to energizing of the coil to shift the valve element into one of its positions, resilient means urging the valve element into its other position and that moves the valve element into said other position when the supply of energy to the coil is shut off, a latch beyond the end of the stem and in substantial alignment therewith, the latch being movable between operative and inoperative position independently of the movement of the valve and stem, said latch when in operative ,position being effective to prevent movement of the valve element and the stem means by said resilient means, and an actuator for the latch adjacent to the coil and in the magnetic field of the coil and movable by said magnetic field to shift the latch into said operative position in which the latch holds the stem means and valve element in the position to which they are moved by the coil.

2. The magnetically actuated valve described in claim 1 characterized by the actuator for the latch including a polarized element that moves the latch in one direction or the other depending upon the direction of current flow in the coil, and means for changing the polarity of the current supplied to the coil.

3. The magnetically actuated valve described in claim 2 characterized by the polarized element being a permanent magnet, a support on which said permanent magne't has angular movement about an axis transverse of the direction of movement of the valve element and stem means, the latch being connected with said permanent magnet for movement therewith.

4. The magnetically actuated valve described in claim 3 characterized by the latch being a cam that has angular movement about said axis, the cam in one angular position being at a location to block movement of the stem means, and in another angular position being spaced from the stem means as the valve element travels to the position from which it was displaced by the magnetic coil.

5. The magnetically actuated valve described in claim 2 characterized by the valve element being movable by the magnetic coil to a position somewhat beyond that in which the valve element is held by the latch so as to take the load of the resilient means off the latch when the magnetic coil is energized with reverse polarity for shifting the latch into its inactive location.

6. In a magnetically actuated valve, a housing enclosing a valve chamber, a seat in the chamber, a valve movable toward and from the seat to shift the valve between closed and open positions, stem means that move as a unit with the valve, a magnetic coil that moves the stem means in response to energizing of the coil to shift the valve into one of its positions, resilient means urging the valve into` its other position and that moves the valve into said other position when the supply of energy to the coil is shut off, a latch for preventing operation of said resilient means, the latch being located in position to move into an operative position to prevent movement of the valve and the stem means by said resilient means, and an actuator for the latch adjacent to the coil and in the magnetic field of the coil and movable by said magnetic field to shift the `latch into said operative position in which the latch holds the stem means and valve in the position to which they are moved by the coil, the actuator for the latch including a polarized element that moves the latch in one direction or the other depending upon the direction of current flow in the coil, means for changing the polarity of the current supplied to the coil, the valve being movable by the magnetic coil to a position somewhat beyond that in which the valve is held by the latch so as to take the load of the resilient means off the latch when the magnetic coil is energized with reverse polarity for shifting the latch into its inactive location, characterized by the valve being a three-way valve with two valve elements that move in opposite directions to close, the valve elements being connected with one another so that onevalve element is in open position when the other is in closed position, and both of said valve elements being movable with the same stem means and j being operated by said magnetic coil, one

of the valve elements being held in closed position by said resilient means when the magnetic coil is de-energized and the latch is 4in its inactive location, and the other of said valve elements being held in closed position by the latch when the latch is in its operative position, there being some yield in the assembly so that the stem means are movable -by the magnetic coil enough to unload the latch when the magnetic coil is energized with reverse polarity for shifting the latch into its inoperative position.

7. The magnetically actuated valve described in claim 6 characterized by the seat against which the valve element is closed by energizing of the magnetic coil being resilient and providing at least a substantial part of the yield in the assembly to unload the latch,-when the magnetic coil is energized with reverse polarity for shifting the latch into its inoperative position.

8. The magnetically actuated valve described in claim 1 characterized by the latch being a cam located adjacent to the end of the stem means that is remote from the valve elements, the stem means extending axially through a longitudinal opening in the center of the magnetic coil, an

armature across the end of the coil remote from the valve elements and connected with the stem means for displacing the stem means toward the valve elements when the coil is energized, the latch being close to said armature and having a permanent magnet connected with the cam for rotating the cam in response to displacement of the bar magnet by the stray ux on the side of the armature opposite the magnetic coil.

9. The magnetically actuated valve described in claim 8 characterized by a structure extending across the cam, and an adjustable stop carried by said structure and movable into position for contact with the cam.

10. 'I'hemagnetically actuated valve described in claim 9 characterized by the adjustable stop being a screw threaded through said structure and movable longitudinally toward and from the path of the cam.

11. The combination with a valve element that moves between open and closed positions, of electromagnetic means that move the valve element to a first of said positions, resilient means urging the valve element toward a second of said positions, locking means beyond the end of the stem and in substantial alignment therewith, the locking means being movable between operative and inoperative position independently of the valve element and stem, said locking means when in operative position being effective to hold the valve element in its first position against the force of the resilient means beyond the time that the electromagnetic means is energized, an actuator for the locking means operated by the ux of said electromagnetic means to move the locking means into said operative position, and a selectively operated control for preventing operation of said actuator.

12. The combination with a valve element'that moves between open and closed positions, of electromagnetic means that move the valve element into a first of said positions, resilient means urging the valve element toward a second of said positions, means for selectively supplying current of opposite polarity to the electromagnetic means at different times, the electromagnetic means being effective to` operate the valve element in the same direction regardless of the polarity of the current flow, locking means movable between an inoperative position and an operative position in which it holds the valve element in its irst position against the force of the resilient means beyond the time that the electromagnetic means is energized, an actuator for the locking means operated by the flux of said electromagnetic means to move the locking means into one position or the other depending upon the polarity of the current supply, characterized by the locking means including an angularly movable element, an axle by which said element is carried and about the axis of which said element has its angular movement to shift it between operative and inoperative position, and means supporting the axle in a relatively lixed position with respect to the valve element and the electromagnetic means. 13. The apparatus described in claim 12 characterized by the angularly movable element having a circumferential surface that holds the valve element in its first position, said surface having a notch at one location of sui- 5 cient radial depth to permit the valve element to move into its second position, the actuator for the movable element being a permanent magnet supported from the same axle as the movable element and movable as a unit with said movable element, and a frame along which the means supporting the axle is adjustable toward and from the valve element.

References Cited y UNITED STATES PATENTS l 320,106 6/1885 White 251-141 X 2,863,628 12/1958 Rimshaet a1 .251-141 X M. CARY NELSON, Primary Examiner I. R. DWELLE, Assistant Examiner U.S. Cl. X.R.