US2472728A - Front type thermostat mounting - Google Patents

Description

June 7, 1949. I J, SANDERS 7 2,472,728

FRONT TYPE THERMOSTAT MOUNTING Filed March 1, 1946 2 Sheets-Sheet l INVEN TOR. f/mare Jana are BY MM AA-QWM A r ram/V57 June 7, 1949. E. J. SANDERS 2,472,728

FRONT TYPE THERMOSTAT MOUNTING I Filed March 1, 1946 2 Sheets-Sheet 2 I l N V EN TOR. E/marz c/. Jam/era JMMW ATTORNEY Patented June 7, 1949 FRONT TYPE THEBMOSTAT MOUNTING Elmore J. Sanders, San Gabriel, Calif., assignor to Evans Products Company, Detroit, Mich., a

corporation of Delaware Application March 1, 1946, Serial No. 651,071

1 Claim.

This invention relates to variable pitch fan blade assemblies used in connection with a cooling system of an internal combustion engine, the pitch of the fan blades varying in accordance with the requirements as indicated by the temperature of the circulating cooling liquid.

An object of this invention is to produce a compact and efiicient fan assembly in which the pitch of the fan blades are varied in response to the transverse movement of a thermostat disposed in the liquid cooling system to substantially reduce the power required to operate the fan when a lesser amount of air circulation is needed.

Another object of this invention is to produce an improved variable pitch fan blade assembly in which an adapter mounts the thermostat and liquid housing on the front of the fan assembly in a manner enabling the rotational movements of the fan assembly in relation to the associated thermostat housing.

Another object of this invention is to provide a liquid temperature actuating means for varying the pitch of the fan blades, said means being mounted on the front end of the fan assembly where less support is necessary and enabling the use of a simplified and easily accessible unit.

Other objects and advantages will hereinafter appear and for purposes of illustration but not of limitation, an embodiment of the invention is shown in the accompanying drawings in which:

Figure 1 is a perspective front view of a fan assembly rotatably mounted on the front end of a stationary internal combustion engine and showing the thermostat housing stationarily mounted on the front end of the fan assembly.

Figure 2 is a horizontal sectional view taken through the fan assembly and the attached thermostat members in which many of the members are not sectioned for purposes of clarity in the illustration. The view is taken along the line 2-2 of Figure 1.

Figure 3 is a sectional view taken along the line 3-3 of Figure 2 showing the eccentrically mounted pin in relation to the centrally mounted fan blade for transmitting substantially linear movement of the one to rotational movement of the other effecting fan blade turning movements.

In the illustrated embodiment of the invention In indicates an internal combustion engine having a crankshaft (not shown) which mounts a belt pulley II, the peripheral grooves i2 thereof being operatively engaged by multiple continuous belts I3 'for transmitting the powered rotational movements of the pulley to the other units ll associated with the engine It.

As illustrated, the fan assembly F hereinafter more fully described, comprises split hub sections l5 held together by bolts [5a and enclosed by side casings 15b secured to said assembled hub by bolts I50. Bolts l6 interconnecting the belt pulley II with the rearward casing l5b securely mounts the fan assembly for rotational movement concomitantly with the belt pulley. It is to be understood, however, that rotary movements may be imparted to the fan assembly by other crankshaft take-01f means, one such other means comprising a separately mounted shaft and pulley.

Associated with the forward portion of the fan assembly F is a thermostat housing or jacket ll which comprises a metallic cup-shaped member [8 having a pair of laterally extending tubes l9 and 20 one of which l9 conducts the cooling liquid from the fluid source into the thermostat housing, the other tube 20 providing the return passage for the liquid. Thus the continuous flow of cooling liquid which is forced through the housing by the water pump (not shown) in the fluid system, maintains the housing at the circulating liquid temperature. The fluid source from which the control liquid is bled may include any part of the fluid system which is desired to be controlling, for example, the fluid at the radiator outlet, the engine jacket, the water pump, or the like. 'An outwardly disposed annular flange 2i integral with the inner edge portion of the cup-shaped member l8 abuts a similarly dimensioned annular flange 22 having apertures 23 therein in registry with apertures 23a in the flange 2| through which multiple bolts and nuts 24 operate to secure said flanged members in the assembled relation providing a liquid tight seal. The annular flange 22 forms a part of the disc shaped member 25 which closes the open end of the cup-shaped housing member l8 and has an aperture 26 in the center portion thereof for receipt of a part of the thermostat casing 27a. Disposed within the described housing is a thermostat 21 of the type which imparts transverse shifting movement to a shaft 28 in response to changes in temperatures. Such thermostats are commercially available, a suitable unit being presently marketed under the designation Vernatherm, and since it forms no part of the present invention detailed description thereof is considered unnecessary. Suflice it to say that the shaft 28 is encased by a fluid packing 29 which in turn is tightly enclosed by an axially aligned sleeve 30 which forms an extension of the thermostat casing 21a, said sleeve 30, fitting through the aperture 26, is screw threaded at 3l'on its outer surface for threaded engagement with the screw threaded spindle 32 which is securely connected, as by brazing, to the central portion of the disc shaped closing member 25. Thus the thermostat 21 is securely positioned in the thermostat housing II. The spindle 32 is in the shape of an axially aligned elongate cylinder having its inner end enclosed, but with an aperture 33 therein, enabling translatory shifting movement of an enlarged shaft extension 34 connected concentrically with the thermostat shaft 28. It is obvious that a liquid tight housing is provided in which the body portion of the thermostat is disposed, the attached spindle 32 operating as a mounting member for the thermostat and the housing for connection with the fan blade assembly.

The thermostat housing, as described, is staticnarily mounted on the forward portion of the normally rotating fan assembly and for this purpose it is necessary to provide an adapter 35 having an annular flange 35 integral with the central portion of an axially aligned cup shaped retaining member 31, said annular flange 36 having multiple apertures 38 therein for receipt of bolts 35 securing said flange to the end casing 40 of the fan assembly effecting rotatative movement of said retainer 31 concomitantly with said fan assembly. An aperture 4| in the base 42 of the cup shaped member 3! permits the disposition of the thermostat housing spindle 32 therethrough, the remaining down-turned portion of the base 42 operating as an abutment resisting the outward movement of anti-friction bearings 43 retained within the cup shaped portion. Outward movement of the thermostat housing and attached spindle is prevented by the stop nut 44 screw threadably engaged to the screw threaded end portion 45 of the spindle 32. The anti-friction bearing thus riding between the adapter connected to the fan assembly and the spindle connected to the thermostat housing permits free rotative movement of the fan blade assembly in relation to the latter.

For detailed description of the fan blade assembly F reference is hereby made to a co-pending application Serial No. 564,278, filed November 20, 1944, on which Patent No. 2,437,810 of March 16, 1948 has been issued, and entitled "Variable pitch fan blade assembly wherein the essential features of the mechanism for varying the pitch of the fan blades is set forth and further description thereof is not considered necessary except as the disposition of the adapter and thermostat efiect the relationship of the fan assembly elements. Suflice it to say that the fan blade assembly F comprises a series of fan blades each of which carries a stub shaft 5| mounted between ball bearings 52 disposed within a flanged cup shaped retainer 53 which seats in recessed annular grooves in the split fan hub l5 permitting rotative movement of the fan blade in relation to the fan hub assembly F. Each stub shaft 5| has a screw threaded central by a jack nut 56 which positions the roller bear-' ing 52 and forces the withdrawal of a concentrically depending center pin 51 which tightly fits an aperture 58 in'the fiat disc 58 rotative in the hub opening 60. A key 6| insertable through registered apertures in the pin 51 and the disc 59 maintains the elements in the assembled relation. Each disc carries an eccentrically disposed pin 63 which is operatively engaged by an aperture 63a formed in the outer surface of an portion 55 engaged It is evident that transverse shifting movement of the actuating sleeve will impart rotative movement to the fan blade in relation to the supporting fan hub assembly. Transverse shifting movement is imparted to the actuating sleeve 54 by means of the thermostat 21 through the interconnected axially aligned shafts 28 and 34. For this purpose a sleeve 59 is threadably positioned on the outer end portion of the shaft 34, said sleeve having a shoulder 10 forming an abutment which bears against one end of a series of antifn'ction bearings 'H disposed between said sleeve 69 and the actuating sleeve 64 enabling rotary movement of the latter in relation to the former. The other end of each anti-friction bearing abuts against a shoulder 12 formed on the inner surface of the actuating sleeve, thus rearward shifting movement of the thermostat shaft 28 is concomitantly imparted to the actuating sleeve 54. Movement of the actuating sleeve in the opp site direction is effected by a conically shaped coil spring 13 having the smaller end bearing against the end portion of the crank-shaft and the larger endportion disposed about the conically shaped nose 68, the outer end of said spring seating in the recessed groove 85 of the actuating sleeve.

From the description it will be manifest that the pitch of the several fan blades is automatically changed in accordance with the temperature of the cooling liquid which comes in contact with the thermostat 21. Thus the element may be initially adjusted such that when the temperature of the cooling liquid is relatively low, the pitch of the fan blades will be such as to direct a minimum stream of air through the radiator or to the engine, thus saving considerably in the power expended in operating the fan assembly. When the temperature of the cooling liquid rises, the pitch of the fan blade is proportionately changed to direct a greater stream of air to the radiator or engine.

It is manifest that I have produced an automatically operated variable pitch fan blade assembly in which the thermostat responsive to the temperature of the cooling water is mounted in a liquid tight jacket on the forward end of the fan assembly. The resultant longitudinal shifting movement of the thermostat is imparted to the fan blade assembly for varying the pitch of the fan blade irrespective of the turning movements of the fan assembly in relation to the stationarily mounted thermostat housing. In this sense an important feature of this invention resides in the adapter means for mounting the thermostat containing housing on the forward end of a rotating fan assembly.

I have also produced a compact and easily assembled unit in which the fan elements are assembled between split hub sections, the adapter connecting the thermostat housing to the fan assembly permitting assembly and adjustment of the thermostat unit without modification of the fan assembly, and since the thermostat housing does not support other engine members, a

rigid and sturdy support is deemed unnecessary enabling simplification of the structure and mounting.

It is to be understood that numerous changes in the details of construction, arrangement,,and operation may be effected without departing from the spirit of the invention especially as defined in the submitted claim.

What I claim is:

A variable pitch fan for an internal combustion engine, comprising, a hub assembly having a periphery and front and rear sides, means on said rear side for aflixing the hub assembly to a rotating member for rotation therewith, fan blades projecting radially from said periphery, bearing means mounting said blades on said periphery for rotation about their radial axes,

crank means eccentric of said radial axes on the inner ends of said blades, an activating member common toall of said crank means within said hub assr'nbly, said activating member rotating with said hub assembly, bearing means slidably mounting said activating member within said hub assembly for axial movement with respect to said hub assembly, whereby, when said activating member moves axially, said blades are turned about their radial axes, a combined rotary and axial thrust bearing centrally disposed in said activating member including an outer bearing sleeve rotating with said hub assembly about an inner bearing member, the front side of said hub assembly having an axial opening therein, a second combined rotary and axial thrust bearmg having an outer sleeve amxed within said opening and rotating about an inner sleeve, and

a thermostatic control assembly comprising a sleeve, means for afllxing said sleeve within the inner ring of said second bearing member with the front end of said sleeve projecting be 0nd the front side of said hub assembly, a liquid v ight housing amxed to the front end of said 's'leeve,

an axial shaft extending from the inner bearing member of said first combination bearing to said chamber, thermal-responsive means in said chamber for moving said shaft axially upon changes of temperature of said cooling liquid, and means for connecting the interiorof said housing to a source of cooling liquid.

- EIMORE J. SANDERS.

REFERENCES orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS Embery et al Dec. 3, 1935

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