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Publication numberUS58745 A
Publication typeGrant
Publication dateOct 9, 1866
Publication numberUS 58745 A, US 58745A, US-A-58745, US58745 A, US58745A
InventorsP. H. Boots
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Improvement in rotary blowers
US 58745 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

r. r1. noors,



Specification forming part of Letters Patent No. 58,745, dated October 9, 1866.

To all 'whom t may concern:

Be it known that I, I). H.Boo1s,of Gonnersville, in the county of Fayette and State of Indiana, have invented a new and useful Improvement in Rotary Blowers; and I do herebydeclare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure l represents a longitudinal vertical section of this invention. Fig. 2 is a plan or top view of the same. Fig. 3 is a diagram illustrating the construction of the pistons.

Similar letters of reference indicate like parts.

This invention relates to an improvement in that class of rotary blowers on which a patent has been granted to me September 25, 1860.

The object of this present improvement is to modify in any desired degree the proportion of the pistons and recesses of said rotary blowers, which, in the above-named patent, are formed of arcs whose chords are of equal length.

According to my present improvement the arc of the recesses is reduced and that of the pistons is increasedthat is to say, the pistons and recesses are described with the same radius, but the pistons comprise an arc greater than that of the recesses; and my experience shows that the effect of the pump is not impaired by this change in the form of the pistons and recesses, but on the contrary a bencicial result is attained in causing the coacting pistons of the respective abutments to lap instead of simply meeting at their corners, as described in my former patent.

Aand B represent two double-acting rotating abutments, alike in all respects, each having two or more pistons, D D, and two or :more recesses, E E. Said abutments are mounted on shafts@ C, and they are placed in such a position in relation to each other that the pistons of one abutment work or gear in the recesses of the other abutment, and vice versa, as clearly shown in Fig. l of the drawings.

The method in which the pistons and recesses are constructed will be readily understood by referring to the diagram shown in Fig. 3 of the drawings. From the centers of the shafts C C', I describe two circles, c c', which do not touch each other,the distance between their peripheries being more or less, according to the degree of reductionv desired inthe length of arc of the recesses. I then connect the centers of these two circles by a right line, b c, and erect thereon perpendicular lines d c d e', passing through the centers of the circles c c. I then nd a point, f, in the periphery of the circle a which is equidistant from the point of,intersection g between the perpendicular line d e and the periphery of the circle a', and from the point of intersection 7L between the line c d and the periphery of the circle c and the lines gf and hfform the radii-one for the piston D and the other for the recesses E.

It will be readily seen that by these means the arcs of the pistons comprise more than a quarter-circle, and the arcs of the recesses less than a quarter-circle, 011 the inscribed circles a and a; and, furthermore, by increasing the distance between the peripheries of the circles c c in proportion to their diameters the depth of the recesses is reduced. How far this reduction can be carried on without interfering with the practical effect of the blower must be found out by experiments; but according to my present experience I am well satisfied that the recesses may be reduced to a considerable extent without impairin g the correct movements of the abutments, but a material reduction would considerably diminish the capacity of the blower for expelling air.

In the above description I have selected to illustrate my invention abutments having each two pistons and two recesses; but it is evident that the invention is equally applicable to any number.

It must be distinctly understood that I disclaim everything described and contained in my aforesaid patent of September 25, 1860, and also everything contained in the patent of David M. Talker, 1835.

What I claim as new, and desire to secure by Letters Patent, is

l. The rotating abutments A B, each constructed with two or more pistons, D, and 2. Finding the centers and radii for the pisrecesses E, constituting arcs of equal radius, tons and recesses of the rot-ary abutments A but Whose chords are of unequal length, the B in the manner described with reference to chords of the arcs of the pistons D bein g made Fig. 3 of the drawings.

of greater length than those of the recesses I?. H. ROOTS. E, so as to canse the coacting pistons to lap Witnesses:

at and near the angles7 substantially as herein WM. F. MGNAMARA, described. ALEX. F. ROBERTS.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US5702240 *May 5, 1995Dec 30, 1997Tuthill CorporationRotary positive displacement blower having a diverging outlet part
Cooperative ClassificationF04C2/082, F01C21/0809