US2778576A - Temperature responsive actuating devices - Google Patents

Description

Jan. 22, 1957 R. M. JOHNSTON TEMPERATURE RESFONSIVE ACTUATING DEVICES Filed April 6. 1951 WM-W 3 Sheets-Sheet. 1

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Jan. 22, 1957 R. M. JOHNSTON TEMPERATURE RESEONSIVE ACTUATING DEVICES Filed April 6, 1951 l I I 1 u 3 sheets-sheet 2 3m entor @y Mir/12x Jan. 22, 1957 R. M. JOHNSTON 2,773,576

I TEMPERATURE RESPONSI VE ACTUATING DEVICES s sneet-sheet s Eiled April 6, 1951 Smacntor if fiaif/y/yc/hm/v v I I Gttornegs lc Patented Jan. 22,1957

from the top in Figure 2, as indicated by arrows 4-4 in Figure 2;

TEMPERATURE RESPONSIVE ACTUATIN G DEVICES Rodney M. Johnston, Lockport, N. Y., assiwor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application April 6, 1951, Serial No. 219,655

6 Claims. (Cl. 236-99) This invention relates to thermo-responsive actuating means for valves and the like and more particularly to safety means associated with such devices.

Thermo-responsive actuating means for the control valves of vehicle and other types of circulating water type heaters are adjustable usually by manual means to different positions to vary the static positions thereof so that the associated valves may be actuated thereby to or toward open and closed position at dilferent predetermined ambient temperatures. Such valves may also be locked in open or closed position and the associated thermo-responsive means at the same time are held in positions corresponding to such positions of the valves regardless of the temperatures to which they are subjected. Under these conditions should the ambient temperature rise above a normal value the bellows of the thermo-responsive means tends to expand correspondingly but since it is held against movement the increased pressure of the thermo-responsive fluid therein frequently causes undue stress on the parts resulting in damage thereto.

One object of the present invention is to provide safety means which will enable the thermo-responsive valve actuating means to expand beyond a normal extent of movement when subjected to abnormal temperatures, and thereby prevent damage to the associated parts.

Another object is to provide a resilient support for merino-responsive actuating means which enables expansions thereof corresponding to the normal temperature range of operation, but which enables said means to ex pand beyond said normal range of expansion when subjected to abnormally high temperatures. I

A further object is to provide a resilient safety supporting means of the character described on existing thermo-responsive actuating means with a minimum of change or modification.

A still further object is to provide safety resilient supporting means. for thermo-responsive actuating means which is simple in construction, economic in manufacture and highly efficient in operation.

Various other objects, advantages and novel details of construction of this invention will become more apparent as this decription proceeds, especially when considered in connection with the accompanying drawings, in which,

Figure 1 is a fragmentary side elevational View partly broken away and partly in section of a motor vehicle provided with an air heating system employing a thermoresponsive control valve actuating means having the safety means incorporating this invention associated therewith;

Figure 2 is an enlarged elevational view partly in section taken substantially on the plane indicated by line 22 of Figure 1; 4 t

Figure 3 is an enlarged sectional view taken substantially on the plane indicated by line 3-3 in Figure 2, looking in the direction of the arrows;

Figure 4 is an enlarged end elevational view as viewed over the end of the coupling 31 as indicated at ,35. With Figure 5 is an enlarged sectional view of the connection between the valve stem and valve control lever of the device;

Figure 6 is an enlarged sectional view of the connec tion between the valve stem and valve.

Figure 7 is a fragmentary side view showing my improved resilient supporting means for the stem of the thermo-responsive valve actuating means during normal operation of the latter.

Figure 8 is a similar view showing the position of the parts when the thermo-responsive valve actuating means has expanded beyond its normal'extent of movement, and

Figure 9 is a sectional view taken substantially along line 9-9 'of Figure 7.

For the purpose of illustration my invention is shown as applied to the thermo-responsive apparatus shown and described in the copending application of Arthur 'J. Schutt, Serial No. 125,029, filed November 2, 1949, for Temperature Control Valves and now Patent No. 2,663,499, granted December 22, 1953.

Referring now to the drawings and more particularly to Figure 1, it will be noted that there is illustrated, fragmentarily, the front portion of a motor vehicle 10 provided with the usual water cooling radiator 11. The reference character 12 indicates the dashboard of the motor vehicle. interposed in an air conduit 13 extending from the front of the vehicle to and through the dash 12 is a heat exchanger 14.

The particular temperature control valve employed is indicated generally by reference character 15. a

As shown in Figure 1, hot water from the radiator flows through conduit 16 through the temperature control valve 15, then through conduit 17 to the heat exchanger 14 from which it returns by conduit 18 to the radiator 11.

Any other desired system of conduits or connections may be employed, it being essential only in this invention that the control valve be so interposed in the system of conduits that the flow of the heating fluid to the heat exchanger is controlled.

The particular control valve employed is illustrated in detail in Figures 2 to 5 inclusive, in which the reference character 19 indicates a base member peripherally secured as at 20 to the dash 12. Intermediate its periphery and substantially throughout its length, the base 19 is formed with a pressed-out boss 21 which boss portion is apertured as at 22.

The reference character 23 indicates a pipe to which the conduit 16 is connected and the reference character 24 indicates a second pipe to which conduit 17 is connected. The pipe 23'is brazed or otherwise secured. to

the pipe 24 and the pipe 24 is brazed or otherwise se cured to a circular cap or closing member 25. This member 25 is adapted to receive and support a rubber seal 26 as best illustrated in Figure 5. The assembly consisting of pipes 23 and 24 and the cap or closing member 25 are adapted to be assembled with and secured to the base 19 by having lips or tab portions 27 on the cap member 25 passed through slots in the base 19, said lips or tabs' being subsequently bent over and staked or welded to the base as illustrated.

The reference character 28 indicates a valve shaft which extends through and is guided by an aperture 29 in the cap or closing member 25. One end of this valve stem 28 is provided with a semi-spherical or ball-shaped end 30 to which a coupling member 31 is attached by spinning the same thereon. The reference character 32 indicates a valve and 33 a valve guide mounted on the coupling 31. A washer 34 engages one face of the valve 32 and these three parts are secured in position by clinching this construction the valve 32 is capable of limited universal movement to seat firmly on the valve seat and the valve guide 33 assists in properly seating the valve.

A valve seat 36 is pressed into the pipe 24 and is preferably secured thereto by brazing. In Figure 2 the valve is shown in open position.

The other end 37 of the valve stem 28 is also semispherical and adjacent this end the valve stem is provided with circular grooves 38 and 39. The rubber seal 26, previously referred to, is in the form of a diaphragm and has a circular sleeve portion 48 which surrounds the valve stem 28 at the groove 38 and is secured thereto by a clamp ring 41. A cup-like ferrule member 42 surrounds the valve stem 28 and encloses the sleeve portion 40 of the seal 26. This ferrule is held in place by a hairpin type securing member 43 engaging in said groove 39. When the valve stem 28 is reciprocated, the rubber seal 26 will flex to permit this reciprocal movement.

Secured to the base 19 is a substantially U-shaped case or housing 44. This housingis provided at spaced points with tabs or ears 45 which are passed through corresponding slots in the base 19 and are then bent over or staked as illustrated most clearly in Figure 3.

The reference character 46 indicates a valve control lever extending through the housing or case 44 and pivotally connected thereto at one end by a pivot pin 47. The valve control lever 46 is substantially channelshaped and is thus provided with longitudinally extending side flanges 48, one of which is extended to provide a laterally extending arm or ear 43 for a purpose to be shortly referred to.

The free end of the valve control lever 46 is slotted as at 50 to receive a spring clip 51 one end of which engages the inside of the channel portion of the lever 46 whereas the other end of said clip is slotted to engage the neck portion 52 of the valve stem 28 adjacent the spherical end 37. This spring clip 51 acts to hold the valve stem 28 and valve control lever 46 into engagement with one another during the movement of these parts. Movement of the control lever 46 and consequently of the valve stem 28 is limited in one direction by means of an ear 53 provided by cutting and bending at right angles a portion of the case or housing 44.

Mounted on one side of the case or housing 44 is a cam 54. This cam is mounted on a shaft 55 carried by the adjacent side of housing 44. Secured on the end of the shaft 55 and bearing against the cam for frictionally holding the same against accidental rotation is a spring retainerring 56. The cam 54 is adapted to be oscillated and remotely controlled by a Bowden cable 57 connected to the cam 54 as at 58. For supporting the Bowden cable 57 there is provided a clip 59 secured to the housing 44 with which a clamp 60 cooperates for engaging the Bowden cable. This Bowden cable extends to and through the instrument panel 61 of the motor vehicle where it is provided with an operating knob 62. By means of this Bowden cable the cam 54 may be rotated about its shaft 55 for a purpose to be referred to later in more detail.

Mounted on the arm or ear 49 of the valve control lever 46 is a pin 63. During the oscillation of the cam 54 this pin 63 works in a slot 64 provided in the cam. This slot 64 is of a width to provide clearance around the pin 63 sufficient to permit reciprocation of valve stem 28 during the opening and closing movement of valve 32. However the ends 65 and 66 of this slot are of reduced size so as to snugly receive the pin 63 at the extreme ends of the movement of the cam. Thus when the cam 54 is moved in the direction of arrow A, the pin 63 will be lodged in the reduced end 65' of the slot 7 and when the cam is moved in the direction of arrow .4 67. This bellows frame 67 comprises a substantially circular portion 68 and a pair of opposed angularly extending arms 69. The ends of the arms 69 are provided with lips or tabs 70 which pass through slots in the lever 46 and are bent over or staked as illustrated in Figures 3 and 4. Thus the bellows frame 7 is rigidly secured to and moves with the valve control lever 46.

A cam lever 72 is mounted for rocking movement on a pivot pin or shaft 73 supported on a spring 108. Lever 72 is substantially channel-shaped in cross section having a web 72 and spaced legs 72", 72". Pivot shaft 73 extends through aligned apertures provided in legs 72", 72 and thence through vertical slots 101 and 102 provided in spaced ears 71, 71 struck out from one of the walls of housing 44. The pin or shaft 73 is held against axial movement in one direction by the head 73 thereof engaging the outer side of one of the cars 71 and in the other direction by a collar 73" engaging the outer side of the other ear 71. Collar 73" may be of the spring type secured in a groove in the pin 73 as shown in Fig. 9 or may be held in position by any other suitable means. The resilient supporting means thus provided incorporates the present invention and a more detailed description thereof will appear later herein. One end of the web 72' of cam lever 72 is dished as at 74 to receive the end of a bellows stem 75. This bellows stem extends through an aperture 76 in the valve control lever 46 and is pro vided at its other end with a shoulder 77 upon which rests a head 78. A bellows 79 is interposed between the portions 68 of the bellows frame 67 and the head 78 and is silver soldered or otherwise secured thereto. A capillary tube 80 extends through the frame portion 68 into the interior of the bellows and is securely soldered thereto. This capillary tube may, if desired, be extended to any length and provided with a bulb 81 or if desired the capillary tube and bulb may be eliminated entirely.

In practice the bellows and the capillary tube 88 and bulb 81, if used, are charged with a thermo-responsive fluid. The well-known Freon has been found to work as entirely satisfactorily as the thermo-responsive fluid.

Surrounding the bellows stem 75 is a counterbalancing or range spring 82. At one end this spring engages the valve control lever 46 and the other end engages an adjusting nut 83 mounted on a threaded portion 84 of the bellows stem. The spring 82 is used to counterbalance the pressure exerted in the bellows 79 for a desired or selected air temperature range. Also by adjusting the nut 83 variances in the spring 82. and bellows 79 may be compensated for to fix or adjust the start-to-open temperature of, the device. After final adjustment of nut 83 the threads of threaded portion 84 are peened to prevent further turning with the. nut 83.

The valve control lever 46 is normally biased in a valveopening direction by means of auxiliary spring 85. One end of this spring engages in the channel of thevalve control lever 46 and is prevented from displacement by means of a lip 86 provided by cutting and bending a portion of the lever 46. The other end of this spring surrounds a lip 87 struck from an adjacent portion of the case or housing 44.

The web 72" of cam lever 72 is preferably provided with a projection in the form of a rib 72a adapted to engage the cam face or surface 88 of the cam member 54. This cam face or surface 88 is developed so that when the cam 54 is moved in the direction of arrow A, the cam lever 72 is rocked about its pivot 73 to move the bellows stem 75 in the direction of arrow C. Obviously, therefore, when the cam 54 is moved in the direction of arrow B, the cam lever 72 rocks in the opposite direction and the bellows stem 75 moves in a direction opposite to that indicated by arrow C.

When the cam 54 is moved in the direction of arrow A and cam lever 72 moves bellows stem 75 in the direction of arrow C, the engagement of shoulder 77 on bellows stem 75 with the head 78 acts to compress bellows 79 and through bellows frame 67 rocks valve con With the parts trol lever 46 in valve-closing direction. left in such an adjusted position, a smaller bellows movement is necessary or'required to close the valve.

When the cam member 54 is moved in the direction indicated by arrow B, the contrary'is true. Under these conditions the cam lever 72 is rocked inthe opposite direction and the bellows stem 75 moves in the direction opposite to that indicated by arrow C whereupon the bellows is extended requiring more bellows movement to move the valve 32 to a fully closed position.

When the cam lever 72 is rocked to move the bellows stem in the direction of arrow C, the bellows 79 is not only compressed but the bellows frame 67 is also bodily shifted which in turn rocks the valve control lever 46 to move the valve towards closed position. When the cam lever 72 is rocked in the other direction and the bellows stem 75 moves in the direction opposite to that indicated by arrow C, the bellows is permitted to expand and the valve control lever 45 under the influence of auxiliary spring 85 moves the valve away from its seat.

Thus by. properly adjusting the cam 54, by means of Bowden cable 57 and knob 62, the thermo-responsive means will be adjusted to actuate or open and close the valve within different ranges of temperature variation.

When the valve 32 is opened, the heating fluid will flow through conduit 16 and pipe 23, thence through the valve and through pipe 24 and conduit 17 to the heat exchanger '14 and thence from the heat exchanger 14 through conduit 18 back to the radiator.

A typical operation of the deviceunder average cold weather conditions will now be described. If the cam 54 is adjusted to substantially the position illustrated in Figure 2, the air temperature surrounding the bellows 79 or surrounding the capillary tube 80 or capillary tube and bulb 81 must rise to 70 degrees Fahrenheit to expand the thermo-responsive fluid sutficiently' to close the valve 32 and thus cut oil the supply of heating fluid to the heat exchanger. Therefore at any temperature lower than 70 degrees Fahrenheit, the bellows contracts in proportion to the ambient air temperature and the valve is moved to partially open or fully open position. As the ambient air temperature rises, the thermo-responsive fluid expands thus expanding the bellows and moving the valve toward closed position in proportion to the variances in the air temperature. By properly adjusting the cam 54, the air temperature at which the valve 32 will be closed or opened may be regulated as will be apparent.

It may be desirable to lock the valve 32 in either fully closed or fully opened position so that the valve isnot actuated by variations in the ambient air temperature. For this purpose the reduced end portions 65 and 66 are provided in the slot 64 of cam 54. With this arrangement when the cam 54 is moved in the direction indicated by arrow A whereby the pin 63, carried by the valve control lever 46, is lodged in the reduced end 65 of the slot, the valve is fully closed and when the cam 54 is moved in the direction of arrow B and the pin 63 is lodged in the reduced end 66 of the cam slot, the valve 32 is in full open position. One wall of the slot 64 adjacent the reduced end 65 is provided with a hump or shoulder 65a and another wall of the slot 64 adjacent the reduced end 66 is provided with a hump or shoulder 66a over which the pin 63 passes in the extreme positions of adjustment of the cam 54. When the cam 54 has been thus adjusted to hold the valve 32 in either fully closed or fully opened position, the valve is not aflected by ambient air temperature changes.

Spring 100 is so designed that substantially no flexure thereof occurs during operation of the apparatus as just described.

Spring 100 may be constructed from sheet metal and is formed with a reverse bend intermediate its ends so as to generally resemble a hairpin. One arm 104 of spring 100 is relatively flat and lies against the wall 105 of a recess 106 formed 'inbase 19. The other arm 107 of spring 100 is bent intermediate its ends to form a recess 108 which provides a seat for pivot pin or shaft 73.

Fig. 7 shows the parts in normal position wherein it will be observed that'the pin 73 engages the left-hand ends of the guide slots 101 and 102 provided in ears 71, 71. Spring 100, as previously described, is of sufficient strength to hold pin 73 and consequently lever 72 in this position throughout the normal temperature of operation of the thermo-responsive bellows 79. However, should the ambient temperature rise above a normal value, especially while the valve 32 is locked in either open or closed position, bellows 79 may now expand causing its stem 75 engaging lever 72 to compress spring 100. By this action of bellows 79 counterbalance spring 82 extending between collar 85 on stem 75 and lever 46 is also compressed. When cam 82 is in either of its extreme positions, it will be remembered that the pin 63 is lodged in reduced portions of 65 or 66 of slot 64 thereby locking lever 46 against movement. Therefore spring 82 must be compressed in order to permit bellows 79 to expand against spring 100. By permitting this expansion to take place the pressure of the thermo-responsive fluid in bellows 79 is relieved and as a result damage to the parts is prevented. Fig. 8 shows an extreme condition wherein the spring has been compressed to the fullest required extent bringing pin 73 into engagement with the right-hand ends of slots 101 and 102. Upon lowering of the ambient temperature spring 104 will actuate lever 72 and the bellows 79 toward normal position. It is apparent that the spring 100 and associated parts may be actuated to positions intermediate the extreme positions shown in Figs. 7 and 8 depending upon the degree of abnormality of the ambient temperature. Effective means has thus been provided to protect the thermo-responsive actuating means and associated parts against damage caused by exposure thereof to abnormally high temperatures.

While my improved resilient supporting means has been shown as applied to thermo-responsive actuating devices for valves, it is apparent that it is equally adapted for use in connection with devices of that character employed for other and varied purposes. It is also apparent that certain changes and modifications may be made in the structure and arrangement of parts without departing from my invention. It therefore is to be understood that it is not intended to limit the invention to the specific embodiment shown but only by the scope of the claims which follow.

I claim:

1. In a device of the class described, the combination of a temperature responsive bellows, a lever for adjusting said bellows to condition it for operation within different ranges of temperature variation, a fixed support, a two arm spring, one arm of said spring engaging said fixed support and the other arm forming a resilient fulcrum support for said lever, means operatively connecting said bellows to said lever, and operating means for said lever.

2. In a device of the class described, the combination of a temperature responsive means, a lever for adjusting said means to condition it for operation within different ranges of temperature variation, a fixed support, a fiat spring having a reverse bend therein forming two arms extending in the same general direction, one of said arms engaging said fixed support, means for pivotally mounting said lever on the other of said arms, means operatively connecting said temperature responsive means to said lever, and means for rocking said lever on said pivotal mounting.

3. In a device of the class described, the combination of a temperature responsive means, a lever for adjusting said means to condition it for operation within different I ranges of temperature variation, a fixed support, a two arrears means for pivot-ally mounting said. lever on the said other of said arms comprising, spaced members having elongated guide means therein, fulcrum means for said lever extending into said recess and engaging said guide means, means operatively connecting said temperature responsive means to said lever, and means for rocking said lever on said fulcrum means.

4-. In a device of the class described, the combination of a temperature responsive bellows, a lever for adjusting said bellows to condition it for operation within different ranges of temperature variation, a fixed support, a two arm spring, one of said arms engaging said support, the other of said arms having a recess formed therein, means for pivotally mounting said lever on said other of said arms comprising, a pair of spaced guide members having elongated guide slots therein, a fulcrum pin for said lever seating in said recess and extending into said guide slots to guide said lever during displacement thereof upon flexing of said spring, means operatively connecting said bellows to said lever, and cam means for rocking said lever about said fulcrum pin to adjust the operating characteristics of said bellows.

5. In a device of the class described, the combination of a member adapted for movement between limiting positions in opposite directions, temperature responsive means for operating said member, a counterbalancing spring disposed between said member and said temperature responsive means through which movement of said temperature responsive means is imparted to said member in one direction, a lever for adjusting said temperature responsive means to condition it for operation within difierent ranges of temperature variation, and means enabling expansion of said temperature responsive means beyond the extent required for operation of said member between said limiting positions, said last means cotnprising, a two arm spring, a fixed support, one of said arms engaging said fixed support, and fulcrum means for said lever mounted on the other of said arms.

6. In a device of the class described, the combination of a valve adapted for movement between fully open and fully closed position, operating, means for said valve including an actuating lever, a temperature responsive bellows having a normally substantially stationary end and a normally movable end and a counterbalancing spring disposed between said normally substantially stationary end of said bellows and said lever, an adjusting lever for adjusting said temperature responsive means to condition it for operation within ditterent ranges of temperature variation, means for connecting the said normally substantially stationary end of said bellows to said adjusting lever, means for rocking said adjusting lever to adjust said temperature responsive means, means for locking said actuating lever in positions corresponding to fully open and fully closed positions of said valve, and means enabling. expansion of said temperature responsive means, when said valve is held in fully open and fully closed positions, said last mentioned means comprising a two arm spring, a fixed support, one of said arms engaging said fixed support, and means for pivotally mounting said adjusting lever on the other of said arms.

References Cited in the file of this patent UNITED STATES PATENTS 1,545,990 Weeks July 14, 1925 1,815,030 Almanrode July 21, 1931 1,847,911 Trane Mar. 1, 1932 2,033,410 Dezotell Mar. 10, 1936 2,154,108 Olson Apr. 11, 1939 2,350,137 Weber May 30, 1944 2,487,438 Gryce Nov. 8, 1949 2,537,315 Newton Jan. 9, 1951 2,556,603 Senn June 12, 1951 2,575,081 Watkins Nov. 13, 1951 2,577,450 Carter Dec. 4, 1951 2,602,593 Raney July 8, 1952 2,663,499 Schutt Dec. 22, 1953 FOREIGN PATENTS 487,671 Great Britain June 20, 1938 577,981 Great Britain June 11, 1946

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