US2353350A - Actuating means - Google Patents

Description

' y 1944. c. H. MILLERWISE 2,353,350

ACTUATING, MEANS Filed Sept. 14, 1942 INVENTOR M ATTORNEY Patented July 11, 1944 ACTUATING MEANS Carl R. Millerwise, Detroit, Mich, assignor to Detroit Lubricator Company, Detroit, Mich, a

corporation of Mic Application September 14, 1942, Serial No. 458,207

6 Claims.

.-This invention relates to new and useful improvements in actuating means and more particularly to a thermostatic operating device.

An object of the invention is to provide means to compensate for variation in the heat input to an electrically energized heat motor.

Another object is to provide means to reduce a part of this specification, there is fully and clearly illustrated a preferred embodiment of the invention, in which drawing:

Figure 1 is a view in side elevation and partly in vertical section of the operating device as applied to a flow controlling valve;

Fig. 2 is a plan view in section on the line 2--2 of Fig. 1;

Fig. 3 is a detail view in prospective of a heating element;

Fig. 4 is a detail View in side elevation showing the energized position of the operating device,

and

Fig. 5 is a detail view in section on the line 3--5 of Fig. 2.

Referring to the drawing by characters of reference, l designates generally a valve having a casing with a flow passageway therethrough controlled by a valve member 2 having a longitudinally reciprocal stem 3 which extends upward through a valve bonnet 4 and is guided at its upper end in a guide member 5. Supported on the bonnet 4 and surrounding the stem 3, there is a permanent magnet 3 of annular form which is secured to the bonnet 4 by welding, or the like. Carried about and rigidly fixed on the stem 3 between the magnet 6 and the guide member 5, there is an armature I cooperable with the magnet 3 and formed by the lower annular flange of a collar member 8 having an upper annular flange 9. Also mounted on the bonnet 4, there is a housing In which encloses the valve superstructure and which has a removable cover member ll.

Also positioned within the housing Hi, there is a thermostatic operating device l2 carried by the housing or end wall l3. Securedto the wall l3, there is a horizontal bracket or supporting member l4 having horizontally spaced and vertically positioned yolk type supporting arms which receive and journal the end trunnions l6 of a horizontally positioned, rectangular supporting baror member l1. Secured to the bottom face of the bar l1, and extending therefrom toward the collar 8, there is an electrically energized thermostatic heat motor l3 having a bimetal operating element l9, preferably a flat plate of substantially truncated triangular form tapering toward the stem 3 and having an end slot to provide arms 20, 2| which can bear upward at substantially diametrically opposite points against the under face of flange 9. The arm 2| has a downturned or directed end extension 22 engageable with the top face of armature flange 1. Secured tightly to the underface of the bimetal element l9, there is an electric resistance heating element 23, see Fig. 3, faced by top and bottom sheets of electric insulating material 24, 25 respectively, such as mica. The heating means 23 comprises an electrical resistance coil 26 wound in zig zag form on the upper face of an insulating sheet 21, preferably of mica. The element 23 and the sheets 24, 25 are of truncated triangular form to conform to the bimetal element l9 and are secured to the bar I! and at their outer end are held by clips 28 to the element l9. Secured to and extending from the top face of the bar l1, there is a, thermostatic compensating element 29, preferably a flat bimetal plate of truncated triangular form having an end slot 30 in its free end to receive an adjustment screw 3| with an upward facing flange 32 on which the free end of the element 29 seats at diametrically opposite points.

Positioned between the element 29 and the bar ll, there is a sheet metal heat-conducting member 33 of truncated triangular form which is bent downward, as at 34, for substantially half the distance between the elements 13 and 29 and is then curved convexly downward toward the element I! to lie adjacent, but in spaced relation thereto, as at '35. The elements l9 and 29 and the conducting member 33 are secured to the bar I! by heat conducting nuts and bolts 36. The heating element 23 and the insulating sheets 24, 25 are secured to the bar H by screws 360. which extend through apertures 31 in the coil sheet 21 to provide binding posts for the ends of coil 26 and .to which the lead wires 38, 39 are secured. The heat conducting member 33 is preferably of hard copper and of about .005" thickness, so that it exerts a relatively slight resistance to upward movement of the element l9 upon engagement of the element l9 therewith.

Operation of the operating device l2, .as applied to the valve of Fig. 1, is as follows. Adjustment of the screw 3| to move the flange 32 downward will increase the time period after energization of heat motor I8, which is required to move the valve to open position, and will also provide a shorter closing time after deenergization of coil 26. Should the ambient temperature within the housing l increase, then the compensating element 29 will bow or warp convexly downward so as to compensate for the convexly downward bowing or warping of the element I9, which bowing of element i9 would otherwise tend to move the valve toward open position. When the circuit is closed through lead wires 38, 39 to energize coil 26 and impart heat to the element IS, the element l9 will tend to bow upward at its flange engaging portions 20, 2| and when the potential force has increased sufflciently to overcome the magnet B, then the valve member 2 will be moved quickly toward open position, bringing the element l 9 into engagement with the heat conducting member 33. When the valve has moved to full open position, the element 29 will compensate for increase in ambient temperature within the housing I0 and also, by radiation and conduction through the screws 36 and'the member 33, will compensate for any variation in heat imparted to the element l9 such as would result from voltage fluctuation. This compensation will rock the bar I! counterclockwise facing Fig. 1 so that the force of the element l9 acting to hold the valve in full open position will remain substantially constant irrespective of continued heating of the element l9. The member 33 serves to dissipate heat from the element l9 both by conduction of heat from the element I9 to the compensating element 29 and also by radiation from the surface of the member 33. The heat transfer from the element l9 to the member 33, of which a part is conducted to the element 29, serves to completely compensate for temperature increase of the element l9 and to maintain the tension of the element l9 such that upon breaking of circuit through leadwires 38, 39 and deenergization of coil 26, the free end of the element I 9 will substantially immediately move downward with consequent movement of the valve member 2 toward closed position. Not only does the member 33 enhance the compensation afforded 'by the element 29, but it also, during downward movement of the element l9 after deenergization of coil 26, serves to increase the cooling rate of the element I 9 by dissipation of heat therefrom. It will be noted that the member 33 by its spacing from the element IS in the deenergized and cold position of the device l2 does not abstract heat from the element l9 until the element has started to move the valve toward open position, and until sufilcient heat has been stored in the element l9 to assure its operation with a minimum time lag. It will, of course, be understood that the element 29 will bow convexly upward, thereby rotating the bar I I clockwise facing Fig. 1, should there be a drop in ambient temperature which would cause the element l9 to "bow downward at its flange engaging end portions 20, 2|, thereby to hold the end portions 20, 2| in contact with the flange 9.

What is claimed and is desired to be secured by Letters Patent of the United States is:

1. An automatic actuator comprising a control device, a bimetal operating element for moving said device, electric heating means for said element, a movable supporting member for said element, a bimetal compensating element operable to move said supporting member to change the position of said operating element relative to said device, and a heat conducting member operable to transmit heat to said compensating element from said operating element, said conducting member being spaced from one of said elements and engaged with the other of said elements and being engageable with said one element upon movement of said operating element thereb to control the movement of said device by said operating element by conduction of heat from said operating element to said compensating element.

2. An automatic actuator comprising a control device, a bimetal operating element for moving said device, electric heating means for said element, a movable supporting member for said element, a bimetal compensating element operable to move said supporting member to change the position of said operating element relative to said device, and a heat conducting member extending from said compensating element, said conducting member being spaced from and in the path of movement of said operating element for engagement therewith, thereby to control the movement of said device by said operating element by conduction of heat to said compensating element.

3. An automatic actuator comprising a control device, a bimetal operating element for moving said device, electric heating means for said element, a movable supporting member for said element, a bimetal compensating element operable to move said suspporting member to change the position of said operating element relative to said device, and a resilient heat conducting mem- 'ber extending from said compensating element, said conducting member being spaced 'from and in the path of movement of said operating element for engagement thereby and movement therewith, thereby to control the movement of said device by said operating element by conduction of heat to said compensating element.

4. An automatic actuator comprising a movable supporting member, a bimetal operating ele- 'ber to change the position of said compensating element.

5. An automatic actuator comprising a movable supporting member, a thermostatic element secured to said member, heating means for said element, a thermostatic element operable to move said supporting member to change the position of said first-named thermostatic element, a heat conducting member for transmitting heat to said second-named thermostatic element, said heat conducting member having a portion in the path of movement of and spaced from said first-named thermostatic element, said heat conducting member upon contact by said first-named thermostatic element transmitting heat from said firstnamed to said second-named thermostatic element thereby to change the movement of said first-named thermostatic element in response to the heat imparted thereto by said heating means and to change the position of said supporting member.

being spaced from and in the path of movement of said operating element, an electric heating element secured in intimate heat exchange relation to said operating element, means securing said elements and said conducting member to said bar, and means supporting the free end 01 said compensating element so that warping of said compensating element will change the position of the free end of said operating element.

CARL H. MILLERWISE.

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