US2723846A - Delayed actuator - Google Patents

Description

NOV. 15, 1955 HOLDER ET AL 2,723,846

DELAYED ACTUATOR Filed Feb. 13, 1951 F1E E INVENTORS ALFRED E. HOLDER y MAN/P60 #0105? U iwd States Patent DELAYED ACTUATOR Alfred E. Holder and Manfred Holder, Cleveland, Ohio Application February 13, 1951, Serial No. 210,675

6 Claims. to]. 2 67-1) Our invention pertains to a delay-actuator of the type which employs the dashpot or check principle, hydraulically or pneumatically, which is intended for pre-setting (usually, manually) and which is adapted, by its own stored power and after an adjustably variable lapse of time, to have certain of its parts restored to their original, quiescent relative positions. Of innumerable uses to which such an appliance in different sizes might be put, mention is made of only two, namely, the deferred actuation of a camera shutter and as part of a socalled timeswitch for the control of an electrical connection.

The objects of this invention besides reliability of operation and durability while sufiiciently economical of manufacture are:

1) The use with a member (during its force-transmitting and fluid-influenced return movement following its release from a pre-set relationship or arrangement of its parts) of a porous element through which an oozing or seepage becomes exclusively restricted. The fluid in a sealed container may be either of gaseous or of liquid form and the density or greater permeability of the porous material will be selected accordingly; that is, with a liquid content the pores may be coarser or the porosity greater. Commonly, as exemplified, a compression spring acting against a plunger will communicate a thrust to a stem emerging from the container to exercise the desired function after a predeterminable interval of time.

(2) Employment of automatically operable valve means, designed, arranged and adapted to open during the pre-setting movement whereby to furnish an additional and comparatively expeditious by-passage for the alternately shiftable fluid and incidentally to lessen its resistance, but which valve will become closed upon occurrence of a release movement by functional exercise of the spring, to compel any restoration of the pressure equilibrium on opposite sides of the plunger to be dependent upon a gradual transfer through the porous mass.

(3) The introduction into the container, of any suitable fluid of a difierent viscosity whereby a pair of delayed actions of foreknown different time periods become selectively available according to which one of two relatively inverted positions of the entire assembly is adopted during the pre-setting performance and consequent to whether the heavier or the lighter grade of fluid, say, a merely exemplifying oil, is adjacent to the seepage entry side of the porous material so that the ooze through the latter is more or less slow respectively. In our first successful demonstration of that further advantage to be realized by use of this construction, the delayed actions were ninety (90) seconds and fifteen (15) seconds respectively.

(4) Provision of a cup-shaped cover on one end of an optionally cylindrical plunger. which cover besides being the porous element has a yieldable annular flange adapted to exercise the function of ,the automatically operable valve. Whilesuch a structure is preferable by reason of its simplicity and economy, it is to be understood that the porous material maybe located elsewhere on the 2,723,846 Patented Nov. 15, 1955 plunger while retaining, between the container wall and the plunger, a valve which is operable in response to axial movement of a plunger and diiferential pressures on opposite sides of the plunger.

Unless simultaneously to serve as the automatically operable valve, the porous material may, for instance, be some naturally or artificially formed and compressed aggregate, glomerate or even a ceramic.

It is to be understood that the scope of this invention, as defined by the granted claims, comprehends equivalent constructions and that the showing of the drawings and the specific descriptions of the figures thereon are merely to exemplify variable mechanical embodiments, arrangements and applications of distinguishing principles of function which are applied.

Adverting to the drawings:

Figure l is an elevation of the side of a structure embodying our invention.

Figure 2 is an end elevation, the right end as viewed in Figure 1.

Figure 3 is mainly an enlarged longitudinal, median section, showing certain interior parts in the position just after commencement of an automatically initiated, functional or return actuation.

Figure 4 is a broken view on irregular line 44 on Figure 3, but with the parts which constitute the novelprinciple-accomplishing features in an altered relationship, which they assume during the pre-setting operation.

Figure 5 is a minor modification of an end connection in substitution for integrality there in Figure 1.

Figure 6 is a broken view of a composite-plunger modification.

A casing 1, as illustrated of cylindrical shape, has one end 2 closed and confines adjacent to such end a compression, coil spring 3, such being an economical form of power-storage means. The other end of the casing 1 is exteriorly threaded at 4 for the cooperating attachment of an intcriorly and complementarily threaded cap 5. The other end of the cap 5 is formed as a neck 6 of reduced diameter and of indeterminate length to terminate as an-exteriorly threaded nipple 7 for convenient connection with any member or mechanism (not shown) which is to be actuated by our invention after the lapse of a determinable interval of time. The cap structure is provided with an axial bore 8 for the slideable accommodation of a rod 9. Radially through the cap 5 and in communication with its bore 8 is a tapped hole 10 for the reception of the complementarily threaded stem of a conventional set-screw 11 whereby the rod 9 may be fixed in any chosen position, if or when desired.

Interiorly, of the casing 1, its cap 5 confines a suitable gasket 12 around the rod 9 and in contact with the gasket is a washer 13 so that the annular margins of both gasket and washer may become pressed against the extremity of the casing 1 whereby to effect a seal of a fluid-fill 14 within it.

The inner end of the rod 9 carries a composite structure serving as a valve-carrying plunger which comprises a head 15 attached to the rod 9 and being of somewhat smaller diameter than the interior of the casing 1. A coacting plunger part 16 may be detachably secured, as by a screw 17, eitherto the head 15 or to the inner extremity of the rod 9 if the latter be extended through both plunger parts which in either case serve to clamp therebetween a valve 18 which is exemplifiedly ofnatural leather and of empirically ascertained porosity for the selected fluid 14. An inspection of the attachable plunger part 16 will disclose the common expedient of having its end which is appositioned to the spring 3 somewhat lessened in diameter whereby it additionally functions both to center the spring by projecting partially therein, but also to provide a seat for the near end of the spring.

Naught being claimed for that interfitting, no further description should be required.

It is to be observed that the side of the plunger part 15 which faces toward the washer 13 is designedly beveled at 19, also that the valve 18 carries a flexible annular flange 20 which projects longitudinally across the axial plane of the beveled, circumferential area 19. As so constructed and in slightly spaced relation to the periphery of the plunger part 15, the flange is adapted with more facility to exercise the function of a porous valve in a supposedly unique manner for successful attainment of a decidedly advantageous result. During the presetting adjustment in response to manual-pressure actuation of the rod 9 in the direction of the arrow indicated thereon in Figure 4 and against the action of the spring 3, the flexible flange 20 will become deflected toward the axis of the casing 1. However, during the automatic initiation of the reversed or release" action of the rod 9 in the direction of the arrow thereon in Figure 3, the flange will rather tightly engage the wall of the casing, substantially to conform thereto, whereby to cause a pre-timed and gradual release because shift of the fluid to the other side of the plunger will be restricted by the circumstance of an indirect and retarded seepage through the porous diaphragm.

The modification of Figure 5 simply consists in the alternative employment of a casing initially open at both ends. The spring-enclosing end of such a casing 21 has a separate head 22 soldered thereto at 23.

The operation is amplified as follows:

Preparatory to employment of this timing mechanism, for delayed actuation of a duly spaced member which is ultimately, after a selectable interval of time, to be impinged by the outer extremity of the rod 9, a pre-setting by application of pressure against such outer rod end (Figure 4) and to compress the spring 3 is necessitated. During that operation the valve 20 will be opened as the flange 19 collapses to permit the fluid readily to pass therearound, indeed, the flange will become forced away from the tube wall appositioned therearound. When, on the other hand, the relation of the parts and most of the fluid is as appears in Figure 3, the initial return, in response to the force exerted by the spring 3, a pressure will be built up in the part of the casing then containing most of the fluid and such pressure continuously tends to and does force the valve flange tightly against with substantial conformity to the casing wall thereby compelling the fluid to reach the side of the plunger where the spring is located through the pores of the exposed area of the leather or equivalent porous valve and consequently retarding the return progress of the rod 9. Meanwhile, during both directions of movement of the rod 9, the beveled area appositioned radially inward to the flange 20 will facilitate the radially directed flexing of the latter. The use of springs of differing strength, the selection of valve mate rial of varying porosity and the selection of fluid mediums simultaneously of different viscosity or other properties all alike furnish adjustable controls or more particularly to time the interval between the moment of release of the force applied against the spring and the moment when the released spring is no longer required to effect movement of the rod 9 because it has impinged against a part of whatever was to be actuated and performed its duty.

To be observed is that the diameter of the plunger 15-16 is measurably less than the diameter of the valve 18 whereby advantageously to ease the collapse (Fig. 4) or partial displacement of the flange of the latter toward the axis and likewise to facilitate the outward expansion (Fig. 3) of the flange until it becomes pressed into conformity with the cylindrical interior wall of the casing 1. Incidentally, an annular section of the middle circular portion of the valve, between its flange and the outer periphery of the plunger, is provided whereby to provide a specific fluid-permeable area during the time when the spring 3' is permitted slowly to expend its stored energy.

The modification of Figure 6 displays two alternative or selectable features, one being the interpositioning between the plunger part 24, which is remote from the spring, and the flange-enclosed side of the valve 25 a clamped-in washer-like disc 26 which is a simple expedient for permitting an adjustability of the time period prior to delayed actuation. If the disc 26 be of less diameter than the plunger part 24 which abuts it, there will be corresponding increase in the width of the exposed annular area capable of exercising its porosity function after the spring 3 has commenced to expend its energy whereby to shorten the time before delayed actuating-contact by the rod occurs outside of the casing. Contrariwise, a greater diameter of the disc 26 will duly lengthen the fluid shift to the spring side of the interior consequent to a reduction of the porosity area. The plunger is further modified by the equivalent substitution of an annular groove 27 in, for the tapering of, its periphery.

We claim:

1. In a delayed actuator, a cylindrical casing for fluid media, an actuating member reciprocably connected through said casing, power-storage means arranged to expend energy for moving said member relative to the casing, a structure carried by the inner end of said member and comprising a valve part designed and arranged with a flexible, annular flange engaging the casing 50 as automatically to open during a presetting movement of said member in a direction counter to that in which force is exerted by the power-storage means and also so as automatically to close in response to fluid-pressure acting on the valve during release of stored power tending to move said member in an opposite direction, said valve part being composed of porous material serving to furnish the only seepage communication therethrough from one end of the casing to its other end in response to release of power when the valve is closed.

2. The combination as recited in claim 1 wherein there is included, adjustment means for varying the effective area of porosity whereby to regulate the interval of operation.

3. In a delayed actuator, the combination of a casing, an actuating member projecting into said casing, a piston structure carried by the inner end of said member and having a flexible margin adapted to function as a valve, a porous part carried by said piston structure, power-storage means for moving said piston in a direction to close said valve whereby said porous part becomes the sole communication between the piston-divided sides of said casing in response to expenditure of power by said storage means, a section of said member within the confines of said margin comprising a predeterminedly located surface which recedes from said flexible margin in radial alinement with the latter.

4. In a delayed actuator, the combination of a cylindrical casing, a rod reciprocably connected through an end of said casing, a spring operatively located between another end of the casing and said rod, a valve part forming an integral unit composed of porous material and detachably carried by said rod, said unit being formed with a flexible margin adjacently to the casing wall and arranged to establish a pressure-contact in response to power stored in said spring whereby to close the valve part and compel communication thereafter solely through said porous part.

5. In an appliance of the character described, the combination of a tubular casing for fluid media, a rod reciprocably mounted in one end of said casing, a porous valve structure having a marginal flange in contact with the interior surface of said casing and detachably carried by the inner end of said rod, said structure comprising a porous part adjacent to said flange, and a compression spring between opposing interior ends of said casing and valve structure and arranged to expend energy axially'in the direction of projection of said flange despite a pressure contact between the flange and casing wall acdetermined porosity and provided with an annular and flexible flange fitted to the interior wall of said casing, said flange projecting in a direction toward the outer end of said rod, clamping means carried by the inner end of said rod and securing a central portion of the porous element while leaving an annular area between its flange and its clamped portion, and a coil spring interposed between the other end of the casing and said clamping means, the force exerted by said spring tending to move said rod outwardly to maintain a pressure contact between the flange and easing wall, said annular area becoming the sole route for delayed, seepage-transfer of liquid from the rod-occupied end of the casing to its spring-occupied end in response to the release of spring-power.

References Cited in the file of this patent UNITED STATES PATENTS 942,623 Dixon Dec. 7, 1909 1,033,348 Rimailho July 23, 1912 1,099,073 Moir June 2, 1914 1,155,981 Wiseley Oct. 5, 1915 1,323,230 Dotson Nov. 25, 1919 2,103,378 Oestnaes et al Dec. 28, 1937 2,119,743 Harrah et al. June 7, 1938 2,190,842 Kuhn Feb. 20, 1940 2,308,404 Thornhill Jan. 12, 1943 2,570,558 Johnson Oct. 9, 1951

Images