US2073710A

US2073710A - Pump and unloading means

Info

Publication number: US2073710A
Application number: US28A
Authority: US
Inventors: Charles L Rayfield
Original assignee: THERMAL UNITS Manufacturing Co
Current assignee: THERMAL UNITS Manufacturing Co
Priority date: 1935-01-02
Filing date: 1935-01-02
Publication date: 1937-03-16
Anticipated expiration: 1954-03-16

Description

March 16, 1937. I L; RAYHELD 2,073,710

PUMP AND UNLOADING MEANS Filed Jan. 2, 1935 .millllllllllllll lllll num g p linml" I MIN b;

Patented Mar; 16, 1937 UNITED. STATE-S PATENT OFFICE rum AND momma mains Charles L. Rayfleld, Chicago, 11]., assignor, by

' mesne assignments, to Thermal Units Manufacturing Company, a corporation of Illinois Application January 2, 1935, Serial No. 2s

The present invention relates to an improved fluid pump and unloading means for automatically equalizing the pump discharge and inlet pressures as soon as the pump is stopped, where- 5 by starting of the pumpis greatly facilitated.

V In the Solomon E. Koplar Patent No. 1,986,584,

issued January 1, 1935, covering Refrigerant pumpingsystemsf, there is described a refrigeeraht pumpingisystem utilizing a pump of thesame general construction; and operation as the pump described herein, and to which the present invention has been applied, although it will be apparentto one skilledin the art that the inven tion in its broad concept may be utilized with other types of pumps:

In the above mentioned patent oil underpres sure is applied in the common chamber between the angularly disposed pumping sections for lubricating and sealing the pumpparts. m A feature of the present invention" resides in the provision of a thrust spring for each of the rotative pump cylinders, these springs being so To this'end theref'is mounted at one end of one of, the pumping sections, a pair of disc members which are arranged for separating move- 35 ment, one of these members'being connected for rotation with the pump cylinder, andprovided with an annular .inclinedupper surface. A plu- 'rality of balls are disposed between the aforementioned disc members, these balls being-reaotained for rotationwith the discs, but free to move-outwardly under the influence of centrifugal'force over the inclined surface into engagement withtheother of the discs; It will therefore be seen that as" these balls arethrown out- 45 wardly,-when the pump reaches a pre-determined f speed, they act as wedges to force the discs apart.

i dvantage'is taken of this relative movement of the discsto operate a valve disposed in a by-pass onnection between the fluid inlet and outletof ing detailed description taken in connection with the accompanying drawing which mystrates a 55 single embodiment thereof, and in which:

, Other objects and ahvantages of the. present :j invention will more fully appear from the follow- Figure 1 is a view in=elevation of a pump embodying the features of the present invention and having broken away portions to show certain details of the pump parts in section;

Figure '2 is an enlarged transverse sectional 5 view taken through the centrifugally actuated valve control means, taken substantially on line II-II of Figure 1; and

. Figure 3 'is'a detailed plan view of one of the disc members of the centrifugally operable valve 10 control means, showingthe annular groove defining an inclined surface on its face.

As shown on the drawing:

As illustrative of my invention, I have chosen to show in Figure 1, pumping apparatus embodyi5 ing the features of the present invention, which, apparatus is adap d for usein a system re-.

. quiring' fluid to be c rculated therethrough under pressure, such as in arefrigerating system. Since my invention is primarily concerned with improvements in the pumpand meansnor equalizing the pressure between the inlet and outlet connections for the fluid to be pumped, when the pump is stopped, it is deemed unnecessary to x show the details of the pumping system, as these would be of conventional design. Consequently, the inlet and outlet connections with check valves therein, which would ordinarily be connected into the'circulatory system, have been shown in their relation to the pump proper. e

In general, the pump comprises a pair of anguiarly disposedpumping sections A and B which are in end to end relationship and deflne -at their juncture, a common chamber Ill.

. The pumping elements in each of thepumping sections are similarly constructed and operate in .the same manner. As aimatter'of fact, the sections A and .B operate in multiple and have their inlet and outietconnections inter-connected. For

or each-set. being disposed in one of the bores in the p um'pin'g section .B and the other piston of that particular setbeing disposed in one of the bores of the cylinder in section A. It will now I be evident that when the cylinder in the'pumping section is rotated by. a drive shaft M, which may be connected to a suitable source of power,

the sets of pistons will act as a coupling between -the cyllnderin section B and the cylinder in section A, thereby causing the cylinders to. rotate -5 and the pistons to be reclprocated within their associated bores.

Each of the rotatable cylinders is seated on a seating disc II and the seating surface of the cylinder is provided with port openings from each of the bores Ii, these port openings being adapted to engage with a suitably disposed intake and discharge port which are connected to an intake line I! and discharge line connection IT.

The pump as thus described is well known in unnecessary In the present construction, it is proposed to provide a thrust spring which will resiliently force the rotatably mounted cylinders against their seats. Referring to Figure 1, the cylinder II is provided with a central stem or shaft 11 at its seat end, this shaft being extended through a suitable opening l8 in the end of thehousing, and supported in an anti-friction bearing 19.

i is shown as comprising the usual type of ball bearings wherein the balls are contained between an innerand outer ball race.

The outer end of the shaft I1 is provided with a contracted threaded portion 20 which deflnes a shoulder Il-against which a disc or washer 22 is held in abutting relationship by means of a nut 23.

surface of the shaft l1 and provides an abutment for one end of a compression spring 2 having its other end'abutting against the'inner ball race of the anti-friction bearing Is. This spring, it is evidenisewill function to longitudinally force the shaft l'l towards the associated end of the pumping section with the result that the cylinder II is forcibly. seated against the seat block or disc II.

The outer end of the, pumping section A is counter-bored as shown at Iland has disposed therein the anti-friction means I! which was mentioned above. There isalso mounted in the Icounterbore 28, a collar or sleeve 28 which terminates at its outer end in an annular ring shap friction means 28. The anti-friction means 28 'rotatably, supports a contracted hub portion 2! of a disc 30 which is secured to the shaft I! for" rotation therewith.

Spaced above the disc II isa second disc 3| socket 33 of the disc 30. v

' The stem and socket connection between the discs I. and SI .enables'the discs to In the present instance, the anti-friction bearing This disc projects outwardly'past the outer.

portion 21 which serves as a retainer'for anti-.

which is vprovided omits lower surface with a depending stem 32 which is in a central outwardly and upwardly, slanting surface 31, so that as the balls II are moved outwardly by centrifugal action, the balls will be raised slightly and contact the confronting surface a of the disc II to shift the disc 31 away from disc". 5-

For encasing the mechanism Just described.

there is provided a cap 38 which terminates at its base portion in an outstanding flange 4. which is secured as by'bolts H to the end of the pump-/ ing section A.

This cap defines a chamber 42 which is in communication by means of

passageways

43 and 44 with the inlet and outlet connections I and I1 respectively.

In axial alignment with the center line of rctation of the disc 3], there is disposed a bushing 45 having a central bore which provides an extension for the passageway 44 and also serves as a valve seat for-a cooperating valve pin ll. This bushing is provided with a diametral slot a which serves as a guide for a pin "a supported in'the valve pin 46.

The valve pin 40 is slidably supported in a socket." which is disposed in the hub portion of the disc ll. this socket on the upper side of the disc. At the inner end of the socket, the valve pin is supported on a thrust ball member ll. Thev pin "a maintains the'pin 40 against movement relative to its seat. v

The inlet and outlet connections I. and II are provided with'suitable check valves II and II respectively. a

' The operation of the valveand its control means will now be considered. when the pump is stopped and no fluid is being pumped into the system, the balls It will be disposed at the inner portion of the groove 31 and lie adjacent the axis of rotation of the' disc 30. In this position, the balls do not engage the disc SI, and the disc 3| will be in its lowermost position by yirtue ofv the action of gravity and the high pressure of the pumped fluid thereon. Since the valve pin 46 is at this time out of engagement with the seat in the bushing 45, communication will be established from the inlet connection through passageway 43, the chamber 42. the passageway 44 and thence to the outlet connection l1, whereby the pumping elements are lay-passed and any pressure which may be in the outlet connection dueito previously running the pump,,will be equalized with theinlet pressure. This will en'-' able the pump t'obe started under little or no "load.

When the pump is started, the disc II will be rotated-and the ball retainer disc 34 will also rotate and revolve the balls around the stem I2. As the pump continues to come .up to speed, a speed will be reached wherein the balls 30 will move outwardly under the influence of centrifugal force and will besliglitly raised due to themclined surface or of the circumferentiaily extending oove, whereby the balls will be mus t into engagement with the confronting face of disc ll, to'raise-the disc and bring the valvepin 46 against its seat. Seating of the valve pin will intercept communication through the chamber 42 between the ways 48 and N, whereupon the pumping element will not be bypassed and fluid will be pumped directly into the system. 1

From the foregoing, it will be apparent that the herein described-invention describes novel means for seating of the rotative cylinders of the pump, and also provides a novel centrifugaldevice which automatically operates to control (I the by-passing o! the pump parts between the inlet and outlet connections or the p mp. wherev by when the pump is stopped, the outlet pressure,

is equalized with the inlet pressure so that the pump may be started under little or no load condition.- 1 a I am aware that many changes may be made and numerous details of construction may be varied through a wide range without departing from the principles of this invention and I. therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by-the scope and spirit of the appended claims.

- I claim as my invention:

1. In a fluid pumping unit having a housing encasing pumping elements, and inlet and outlet connections for fluid to be pumped; a rotatably mounted member projecting to the exterior 'of the housing, said member being rotatable in accordance with the pump speed, a cap disposed over the projecting end of said member and cooperating with the housing to define a chamber, a passageway from said outlet terminating centraily of the top of the cap 'and defining a valve seat, a valve element another passageway associated with said seat,

connecting said chamber 3 and the inlet, and centrifugaliy operated means responsive to the movement of said member for actuating the valve element to control the fl'ow oi fiuid'through the passageways and chamber, said passageways and chamber cooperating to form a by-pass be ween thepump inlet and outlet connections,

,2. A fluid pumping unit comprising an elongated housing, pumping means in said housing including a rotatable member, inlet andoutlet connections for said means, a cap removably and abuttingly secured to one end of the housing and cooperating therewith to mm a chamber, passageways in the housing wall and cap wall connecting the inlet andoutlet connections with said chamber to form a by-pass therethrough, a passageway in the cap wall being in end to end registration with-a passageway in the housing wall; the other end of the cap passageway terminating in the cap wall to define a valve seat,

' and a centrifugally operated valve mechanism in said chamber connected for actuation from said rotatable member and cooperable with said seat v for controlling the flow of fluid in said by-pass.