US767442A - Rotary pump. - Google Patents

Description

No. 767,442. PATENTED AUG. 16, 1904. W. W. ROBINSON.

ROTARY PUMP.

APPLICATION FILED AUG.29, 1903.

2 SHBETSSHEET 1 N0 MODEL.

No. 767,442. PATENTED AUG. 16, 1904. W. W. ROBINSON.

ROTARY PUMP.

APPLIGATION FILED AUG. 29. 1903.

N0 MODEL. 2 SHEETS-SHEET 2.

UNITED STATES I Patented August 16, 1904.

PATENT OrFicE.

ROTARY PUMP.

SPECIFICATION forming part of Letters Patent No. 767,442, dated August 16, 1904.

Application filed August 29, 1903. Serial No. 171,193. (No model.)

To rtZZ whom it may concern:

Be it known that I, IV ALTER W. ROBINSON, a citizen of the United States of America, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Rotary Pumps, of which the following is a specification.

My invention relates to certain new and useful improvements in rotary pumps; and its object is to produce a device of this class which shall be simple and cheap in construction and highly effective in operation.

To this end my invention consists in certain novel features of construction, which are clearly illustrated in the accompanying draw ings and described in this specification.

In the aforesaid drawings, Figure 1 is an elevation of my improved pump, one of the side plates being removed to show the interior construction. Fig. 2 is a vertical longitudinal section through the same. Fig. 3 is a section in the line 3 ,3 of Fig. 2 looking in the direction of the arrow. Fig. 4 is a perspective view of the gate; and Fig. 5is aview similar to Fig. 1, but showing the circular piston and gate in different positions.

Referring to the drawings, A is a chamber made in the form of a flat cylinder and hav' ing pipes B O extending from it. One of these pipes is an inlet-pipe and the other an outlet-pipe; but as this pump, like most rotary pumps, can be run in either direction either pipe may serve either of these purposes. In the center of the chamber A is a shaft D, upon which is eccentrically mounted a circular piston E, keyed against rotation by a key e. The piston is of such size that the point farthest removed from the shaft is in close contact with the wall of the cylinder A, and the thickness of the piston is the same as that of the cylinder, so that as the shaft D is rotated and thepiston E moves around the chamber any fluid therein contained will be forced to move with it.

A hollow tube F is provided, extending radially from the chamber A, and in this tube is a gate G. A cap F closes the top of the tube F, and a spring Gr holds the gate G, which is made with a hollow center, in contact with the piston E. A small perforation g is provided. at the lower end of the gate G, through which a lubricating substance can pass. The gate is in practice filled with some thick lubricating material. The peculiar feature of this gate is that it is circular in crosssection and that it is beveled at its point, as shown in the drawings. In building apump it is much easier to use a circular gate than a gate of any other form, for the reason that the socket in which it reciprocates can be bored out without any great difficulty, while a hole of any other shape is much more expensive to make. The difficulty, however, with a cylindrical gate squared at the bottom is that as the piston rotates the line of contact of the gate therewith swings to one side from the other of the diameter, and a by-pass is provided through which the fluid in the pump can pass from one side of the gate to the other, and so not be forced out of the outlet-pipe. Some means must therefore be provided for keeping the gate in contact with the piston upon a line diametrical of the gate, and this is accomplished by beveling the end thereof. To be theoretically perfect, the gate should be beveled with two faces meeting in amath- 'ematical line, the angle of the bevel being at least enough to make the faces tangent when the periphery of the piston presents the smallest angle to a line running longitudinal of the gate. In practice, however, a gate beveled to a mathematical line would wear out too rapidly,and consequently the point is slightly rounded, but is of such shape as to keep the line of contact of the piston upon the periphery substantially at the diameter of the gate. When the gate is constructed in this manner with a beveled end, it is not necessary to provide means for preventing the gate from rotating in the socket provided for it, for the reason that the pressure of the spring G, which forces the gate into contact with the piston, makes it very difiicult for it to occupy any other position than that shown in the drawings while the piston is in rotation. In fact, with the piston rotated ninety degrees from the position shown in Fig. 1 a considerable amount of extra compression of the spring must be effected before the gate can be rotated. The beveling of the point of the gate therefore has two very desireable fea tures. First, it keeps theline of contact practically diametrical and prevents leakage past the gate, and, second, it prevents rotation of the gate.

I realize that considerable variation is possible in the details of this construction without departing from the spirit of the invention, and I therefore do not intend to limit myself to the specific form herein shown and described.

claim as new and desire to secure by Letters Patent- 1. In a device of the class described,the combination. with a suitable chamber having inlet and exhaust ports, of a rotatable piston eccentrically mounted therein, and a cylindrical spring-pressed gate beveled at its lower end,

' bination with a chamber and inlet and exhaust ports connected therewith, of a rotatable piston eccentrically journaled therein, a cylindrical gate extending radially from the chamber, means for holding the gate in contact with the piston, the gate being provided with a beveled lower end, and no means being provided other than the beveled surfaces for preventing the rotation of the gate.

In witness whereof I have signed the above application for Letters Patent at Chicago, in the county of Cook and State of Illinois, this 24th day of August, A. D. 1903.

WVALTER WV. ROBINSON.

Witnesses:

S. BLIss, M. B. BLIss.

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