US2685341A - Impeller or propeller having adjustable blades - Google Patents

Description

g- 3, 1954 J. c. BUSQUET 2,685,341

IMPELLER OR PROPELLER HAVING ADJUSTABLE BLADES Filed Jan. 11, 1951 2 Sheets-Sheet l I N VEN TOR JAN 6. BZwal/ET ATTZ Aug. 3, 1954 J. c. BUSQUET 2,685,341

IMPELLER 0R PROPELLER HAVING ADJUSTABLE BLADES Filed Jan. 11, 195

l 2 Sheets-Sheet 2 JAN a. BDSQl/ET Patented Aug. 3, 1954 UNITED STATES OFFICE IMPELLER OR PROPELLER HAVING ADJUSTABLE BLADES Netherlands Application January 11, 1951, Serial No. 205,587

Claims priority, application Netherlands January 16, 1950 Claims.

1 My present invention relates to devices for adjusting the vanes of an impeller for a fan, a pump, a water turbine or the like, or of the blades of a ships propeller or an aircraft propeller, in

which during operation the driving gear of the adjusting device is disconnected from the control mechanism.

In adjusting devices of this character the impeller or the propeller is stopped before adjusting the blades, since otherwise the driving gear of the adjusting device would be liable to damage. With a view thereto a brake is provided for reducing th coasting or deceleration time of the impeller or the propeller after the cutting out of the driving motor and for preventing the impeller or the propeller, during said adjustment of the blades, from undu rotation under the influence of forces acting thereon. Also during coasting of the impeller or the propeller the throwing in of the adjusting device may give rise to difliculties.

The object of my present invention is to obviate said drawback. With this object in view, the invention consists herein that the operating member, whereby the control mechanism is connected to or disconnected from the driving gear of the adjusting device, is associated with a movable element cooperating with a part, which is compelled to follow rotation of the impeller shaft or of the propeller shaft and adapted, during rotation of said shaft, to prevent the control mechanism from being connected to the driving gear of the adjusting device.

In order that my invention may be more fully understood, I shall now proceed to describe two embodiments thereof with reference to Figs. 1, 2 and 3, and Figs. 4 and 4a, respectively, of the annexed drawing, wherein:

Fig. l is a longitudinal sectional view, partly in elevation, of a fan having adjustable blades and provided with a device in accordance with the invention,

Fig. 2 is a longitudinal sectional view, drawn on an enlarged scale, of the driving gear of the adjustable blades, and

Fig. 3 is a cross-sectional view along the line III-III in Fig. 1, also drawn on an enlarged scale.

Fig. 4 is a side elevation, partly in section, of

2 an adjusting device in accordance with the invention, and

Fig. 4a shows in rear elevation a detail of said device.

In accordance with Figs. 1, 2 and 3, the stems 2 of the blades 1 are rotatably mounted in the hub 4 of the impeller, which hub is secured to the shaft 3 of the fan. Also secured to said shaft is the hub member 5, and slidably mounted on, but locked against rotation relative to said hub member is th adjusting disk 5. Each blade is associated with the disk 6 through an arm i, one end of which engages the stem of the blade, the other end being hinged to disk 6. Threaded in disk 6 ar a plurality of, for instance three selfbraking screw spindles 8, which are rotatably mounted in the hub member 5 but prevented from axial movement relative thereto. Secured to each of said spindles is a spur pinion 9. All pinions 9 mesh with a spur wheel integral with the bevel gear H], which is loosely mounted on the shaft 3 and adapted to cooperate with the bevel pinion l3. Secured to the shaft 3, on the left hand side of the gear Ill in Fig. 2, is a ratchet wheel I! adapted to cooperate with a ratchet I2 (see Fig. 3) pivoted to the inner end of a rod Hi and loaded by a spring I5.

It is to be noted that the ratchet wheel H is the part and that the ratchet i2 is the movable element referred to in the third paragraph of this specification.

In order that the bevel gears l0 and it may be moved into mesh so as to effect adjustment of the blades l, the operating member constituted as a hand wheel l5 (Fig. 3) is secured to screw spindle ll, which is locked against lengthwise movement and cooperates with a nut l8 having diametrically opposed stud pins engaged by slots in one end of the bifurcated lever it, the other end of which is pivoted to the collar 2! on the shaft 28 of the pinion l3. Intermediate its ends, th lever is is pivoted to a link, which itself is pivoted to the rod [4. Shaft 20 is loaded by the coiled spring 25 bearing against the collar 2% and to a frame part. In this connection it is to be remarked, that the mechanism described in this paragraph is the control mechanism referred to in the third paragraph 'of this specification.

Assuming the impeller to rotate, irrespective of whether its speed is high or low, then, if the handwheel It is turned in the proper direction with a view to bringing the bevel gears i0, i3 into mesh, the nut I8 will move outwards, i. e. towards the wheel 16, but the lever is will swing about the trunnions of the collar 2! in outward position, so that the rod IA and the ratchet l2 pivoted thereto are also moved outwards. Owing thereto, the tail of the ratchet i2 rides downhill on the cam face 22 under the influence of the spring 15, which urges the ratchet towards the ratchet wheel H. However, since this ratchet wheel rotates in the direction indicated by the arrow in Fig. 3, the ratchet 12 will not be caught in said wheel but idly slid thereon, until the nut l8 abuts against the collar 23 on the spindle I! so as to prevent handwheel it from further rotation.

Consequently, the shaft 20 cannot be raised and the bevel pinion i3 cannot be brought into mesh with the bevel gear It].

If, however, the fan stands idle, outward movement of the nut it by rotation of the handwheel [6 will cause the ratchet i2 to immediately catch in the ratchet wheel H, which, under these conditions, will also be stationary, so that the pivot 24 cannot descend and the lever 19, owing to its swinging movement about the said pivot, will raise the collar 2i and the shaft 20 against the thrust of the coiled spring 25, whereby the bevel pinion I3 is brought into mesh with the bevel gear Ill. During this upward movement of shaft 26, a dog 21 on this shaft engages a notch in the hub of the handwheel 25, so that rotation of this handwheel will be transmitted, through the selfbraking threaded connection between the screws 8 and the disk 6, to the blades i, which are thereby angularly adjusted. This adjustment can be read on an indicator 28, which is associated with the shaft 20.

When the blades i have been properly adjusted, the handwheel it is to be turned in a direction whereby the nut on the spindle ii is again moved inwards and the lever is is again swung about the stationary pivot Z i, thereby causing, in cooperation with spring 25, the shaft 20 to be moved away from the shaft 3 and, consequently, the pinion [3 to disengage the gear I0, Simultaneously, the rod 14 is shifted towards the shaft 3, whereby the tail of the ratchet l2 again rides uphill on the cam face l and the ratchet is caused to clear the ratchet wheel i i.

To prevent the fan from starting during the adjustment of the blades 1, the lever 29 is adapted to operate an auxiliary switch (not shown), thereby locking the main switch of the motor, which is provided for driving the fan, as long as the bevel wheels it and I3 are in mesh. Should this electric safety device fail to properly function, the ratchet i2 will become inoperative as soon as the shaft with the ratchet wheel i i keyed thereon are rotated, so that the ratchet, together with the rod I4, is moved outward under the thrust of the spring 25, whereby the shaft 26 is also moved outwards and the pinion I3 is disconnected from the wheel Hi. It will thus be understood that damage of the driving gear owing to undue starting of the fan is positively avoided.

Turning now to Figs. 4 and 4a, it will be seen that a disk 2:? having a circumferential V-groove is secured to the housing forming part or" the hub of the fan. The rod ill here is not provided with a ratchet, as in the embodiment described with reference to Figs. 1-3, but with a tumbler 30 pivoted thereto and fitting the V groove of disk 29, spring blades being provided on either side of the tumbler to normally hold the latter in alignment with the rod I l. The handwheel it for bringing the bevel wheels it, 13 into mesh is adapted to rotate the screw spindle H through the medium of a chain drive, so that rotation of said handwheel causes the nut is to move inwards along said spindle and thereby the lever 12 to swing about the collar 2i. Owing to this swinging movement of the lever i9, the rod 14 is moved towards the shaft 3.

If, now, the fan should still be in operation, the tumbler 3G will swing about its pivot as soon as it is engaged by the walls of the V-groove in the disk 29, so that the rod l4 has freedom of further movement towards the shaft 3, until the nut i8 abuts against the enlarged inner end of the screw spindle IT. This prevents any further rotation of the handwheel It, so that it is impossible for the bevel wheels I0 and [3 to be brought into mesh.

If, however, the fan stands idle, the tumbler 33 will not swing about its pivot when engaging the disk 28, so that it prevents the rod M from further movement towards the shaft 3. Owing thereto, the lever i9 during its swinging movement will urge the shaft 20 inward against the thrust of the spring 25, so that the pinion i3 will mesh with the wheel ii! and the dog 2? of said shaft will be engaged by the notch in the hub of the handwheel 25, the consequence being that further rotation of this handwheel will cause adjustment of the blades 1. The return movement of the shaft 25, i. e. the disconnection of the wheels ill, I3, is brought about by rotation of the handwheel it in opposite direction.

On failure of the electric safety device to operate to prevent starting of the fan as long as the blades are being adjusted, the slightest rotary movement of the fan will cause tumbler 30 to swing out of neutral position, whereupon the spring 25 is adapted to force the pinion 13 out of mesh with the bevel wheel 18.

What I claim is:

1. An impeller or propeller comprising a rotatable member, a plurality of blades pivotally mounted on said rotatable member, means rotatable with and connected to said blades for adjusting said blades about their pivotal mountings, said means including a drive pinion that is rotatable relative to said blades to operate said means and a disc that is in fixed relation with said blades, a movable pinion for engaging said driving pinion to adjust said blades, an operating member, a lever coupled to said operating member and to said movable pinion, a slidable rod connected to said lever, and a lock element pivotally mounted on the end of said rod and cooperative with said disc only when said disc is stationary to provide a fulcrum for said lever and cause meshing movement of said pinion upon operation of said member, said lock element being pivotal upon rotatable movement of said disc to release said rod and permit said lever to float and thereby prevent meshing of said pinions during rotation of said blades.

2. A device as defined in claim 1 comprising spring means between said movable pinion and its support and biasing said movable pinion from engagement with said drive pinion.

3. A device as defined in claim 1 wherein said disc comprises a ratchet wheel and said lock element comprises a pawl.

4. A device as defined in claim 1, wherein said disc has a V-groove-in its periphery, and said lock element comprises a tumbler engageable in said groove.

5. A device as defined in claim 1 wherein said means comprises a crank on each blade, a second disc axially movable relative to said blades, links 5 between said second disc and said blade cranks,

' said disc having at least one internally threaded bore, a rotatable screw axially fixed relative to said blades and threaded in said bore, a pinion fixed on said screw, and a second pinion in mesh with said screw pinion and fixed with said drive pinion.

References Cited in the file of this patent UNITED STATES PATENTS Number Number Name Date Henington Aug. 16, 1921 Figley June 6, 1950 FOREIGN PATENTS Country I Date Switzerland May 16, 1927 Germany Jan. 26, 1920 Great Britain July 2, 1946

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