US2437568A - Pump - Google Patents

Description

March 1948. v R, URSQ 2,437,568

PUMP

Filed April 2, 1945. I Y 3 Sheets-Sheet 1 R. 'F. uR so amh 9, 1948.

a sheets-sheet 2 PUMP Filed April 2, 1945 Y: J, v

INVENTOR.

Maxmh Q, 1948. URSO 2,437,558

PUMP Filed April 2, 1945 3 Sheets-Sheet 3 IN VEN TOR. 7 45, Far.

Patented Mar. 9, 1948 PUMP Ralph F. Urso, Detroit, Mich., ,assignorto Mc- Cord Corporation, Detroit, Mich., a corporation of Maine Application April 2, 1945, Serial No. 586,081

Claims. 1

This invention relates to pumps and has particular reference to a pump which is especially adapted for pumping accurate small amounts of fluids, such as chemicals or lubricants.

1cliPrincipal objects of the invention are to prov e:

A new and improved pump;

A new and improved pump adapted for pumping accurate small quantities of fluid;

A pump which does not employ any valves as such, but rather in which the inlet and outlet ports for the pump are formed integral with the piston and cylinder;

A pump for pumping small,- accurate quantities of fluid in which means are provided for readily varying the output of the pump;

A pump with a novel and efficient driving arrangement for reciprocating and oscillating the pistons thereof.

Other and further objects of the invention will be apparent from the following description and claims and will be understood by reference to the accompanying drawings, of which there are three sheets, which, by way of illustration, show a preferred embodiment and the principles thereof and what I now consider to be the best mode in which I have contemplated applying those principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appendedrclaims. I also contemplate that of the several difierentfeatures of my invention, certain ones thereof may be advantageously employed in some applications separate and apart from the remainder of the features.

In the drawings Fig. 1 is a plan view of a pump embodying the invention;

Fig. 2 is a horizontal sectional View of a pump taken in a plane along the line 2-2 of Fig. 3 but with some of the parts in a different position than as shown in Fig. 3;

Fig. 3 is a vertical sectional view taken gen.- erally along the line 33 of Fig. 1;

Fig. 4 is a transverse sectional view taken along the staggered line 4-4 of Fig. 3;

Fig. 5 is another transverse sectional view taken generally along the line 55 of Fig. 3, looking in the direction of the arrows; and

Fig. 6 is a fragmentary section taken along the line 6-6 of Fig. 4.

As illustrated, a pump embodying the invention and particularly useful as a lubrica-Wl yoke I'B. While the pump as illustrated maybe used as a lubricant pump,-I contemplate that the essential features of my invention as, hereinafter set forth in the claims may be embodied in a pump for other liquids and purposes. The pump cylinderscomprise metallic bodies having accurately finished cylindricalbores I8 in which bores pistons 20 are reciprocably mounted.

Each piston 20 comprises an accurately fin ished plunger having relatively close working fit with the cylinderbore l8. Each plunger 20 projects from the open end of the cylindrical bore and is provided with upper portions 22 which are threaded for receiving stop nuts'24 and 25. The upper portions 22 of the plungers extend through suitable openings in the crosshead 28 of the yoke I6, and as illustrated the stop nuts 24 and 26 are arranged to prevent vertical reciprocatory movement of the crosshead 28 with out a corresponding movement of the plungers' 20. However, the stop nuts 24 and 26 may be arranged in spaced relationship so as to permit relative vertical movement between the cross head 28 and the plungers 20 for shortening the stroke of the plungers 20, the length of the stroke thereof depending upon the spacing of the stop nuts 24 and 26. Each of the upper portions 22 of the plungers is also provided with a toothed member, such as a gear pinion 30, which is fixed to the plunger portion 22 so as to be non-rotatable relative thereto. 7

The crosshead 28 of the yoke' I6 is clamped to the upper end of a connecting rod 32 which is arranged for vertical sliding movement in a hub 34 which, by means of bearings 36 and 38, is rotatably mounted on an annular boss 40 formed on the cover l2, said hub 34 extending through an opening inthe cover l2 defined-by such boss 40 and the connecting rod '32 of the yoke 16 extending through the hub 34 into the interior of the casing Ill. Y

At its lower end the yoke I6 is constructed and arranged to provide a cam member 42 which at its lower end is provided'with apilot 44 reciprocably arranged in a guide 46. The"cam 3 member 42 has a circular opening 48 therethrough about which are equally spaced four cylindrical pockets 50. Each pocket 56 has a cylindrical body or pin 52 fixed therein, the cylindrical surface of the pin projecting inwardly into the opening 48.

A power driven. shaft 54 suitably mounted for rotation in bearings 55 and 58 and having one end projecting from the casing In for connection with a, source of power, is provided at its. other end with a rotating eccentric cam 60 which comprises a segment of a sphere and which is mounted eccentrically upon the shaft 54 so that upon rotation of the shaft 54 the outer spherical surface 62 of the eccentric cam 60 will suecessively contact the pins 52 for the purpose of reciprocating the yoke l6 and the pump pistons 20 as well as oscillating the same about their respective axis.

The. spherical surface 62 of the cam 60 is so arranged relative to the pins 52 that with the parts arranged as illustrated in Fig. 2 and with the shaft turning in the direction of the arrow 64, the surface 62 of the cam will separate from the pin 52 with which it is in contact in Fig. 2 and move to engage the pin 52 at the bottom of the cam member 42,. as illustrated in Fig. 3, so as to effect the discharge stroke of the pump. In Fig. 3 the parts of the pump are shown as arranged at the end of the discharge stroke, whereas in Fig. 2 the cam 60 is shown in its position at the beginning of the discharge stroke.

As the cam surface 62 moves from the position in which it is illustrated in Fig. 2 to that in which it is illustrated in Fig. 3, it will engage the lowermost pin 52 and react thereagainst to bodily move the yoke l6 and cam member 42 downwardly to eflfect the discharge stroke of the P p- The lower end of the piston 20, as illustrated in Fig. 4, is provided with a passage 68, the passage BBI at its lower end communicating with the bottom of the cylinder l8 and at its upper end with a slot Ill forming a valve port in the piston. This port 10 in one position of the piston relative to the cylinder 14 is adapted to communicate with a discharge passage 12 formed in the cover l2, and in another position thereof spaced 180 from that illustrated in Fig. 4, is adapted to communicate with an inlet passage 14 formed in the cover l2. The inlet passage 14- may be suitably connected through a sightv feed 16,, as illustrated in Fig. 6, to a source of fluid. to be pumped (in the present instance lubricant in the casing l0), while the discharge passage 12' is suitably connected through conduit 18 to the system or bearing. to which fluid is to be discharged 'by the pump.

The cam member 42 through the yoke 16 and the hub 34 is also connected to the pistons 20 so as to effect the rotation thereof.v For this purpose a circular rack, such as. a gear 82, is fixedly mounted upon the upperend of the hub 34 to rotate. therewith and has its teeth meshing with the teeth of the pinions so as to rotate the piston 20 one hundred eighty degrees between the intake and discharge. strokes thereof- The ratio of the gears 82 and 3H. and the extent of oscillation of the cam member 42 about the axis of rod 32 is such that oscillation of. the cam member 42 produced by the rotation of the eccentric cam 60. will cause 180 of rotation of the pistons 20 about their axis- After completing the discharge stroke of' the piston 20, continued movement of the cam 60 in the direction of arrow 64 will engage the surface 62 with the left-hand pin 52, as illustrated in Fig. 5. This will shift or oscillate the cam member 42 in a clockwise direction (Fig. 2) to a position of angularity relative to the axis of the shaft 54 equal to but opposite that as illustrated in Fig. 2.

Continued movement of the cam will cause the eccentric surface 62 thereof to cooperate with such top pin 52 to lift the cam member 42 to its upper position so as to effect the intake stroke of the pump. When the cam member 42 is in the position just described, the port 10 will be in alignment with the inlet passage 14.

After completing the intake stroke of the pump, the cam surface 62 will engage the right-hand pin 52 (:Fig. 5) and shift the cam member 4'2 to the position as illustrated in Fig. 2 so as to bring the port 10 into registry with the discharge passage 12, and will thence react on the bottom pin 52' to effect the discharge stroke of the pump.

It will thus be observed that during the inlet and discharge strokes of the pump the piston 20 will not rotate so that the port 10 will remain in registry with the inlet passage T4 or the discharge passage 12, as the case may be, during the inlet and discharge strokes of the pump. In this way f'ull porting of the pump is provided to expedite the inlet of fluid to the pump and the discharge of fluid therefrom.

The open ends of the cylinders 14- through which the plungers project are relieved to accommodate packing 90, and are threaded to accommodate packing nuts 94 so as to prevent escape of fluid from the pump cylinder. As previously indicated, the pump cylinder t8 and piston 20 are preferably extremely accurately. smoothly finished to very close tolerances so as to provide a close working fit therebetween in order to eliminate the necessity of piston rings, etc.

While but two cylinder units are grouped about the gear 82; I contemplate that more than two cylinders may be arranged in' a grouping about the rack 82 and the yoke l5 so as to provide a multiple pump unit of more than two cylinders. The hub 34 is slidably keyed relative to the rod 32 so as to rotate therewith.

It will thus be seen that I have provided a pump comprising a cylinder IB closed at one end and having spaced inlet 14 and discharge 12' ports spaced from the closed end of the cylinder, a reciprocable piston 20 operatively arranged in said cylinder l8 and having a port 10 in its side and a duct 68 extending between such port 10 and the working face of the piston, common means for reciprocating the piston 20 in the cylinder l8 and for rotating the piston 20 to align the port '12 therein with said inlet port 14 at the beginning of the suction stroke of the piston 20 and to align such port 10 in the piston with the outlet port 12 at the beginning of the discharge stroke of the piston, such common reciprocating and rotating means comprising a rotary cam. 62, a yoke 16 including a cam member 42" having four pins 52 arranged parallel. to each other in a circle ninety degrees apart with the axes of said pins normal to said circle and positioned relative to said' rotary cam 62' so that such cam will successively engage said pins 52. Means are provided for mounting said yoke for oscillation about its longitudinal axis and. for reciprocating movement parallel to said axis. such yoke being. connected to said piston 20 for effecting. the reciprocation thereof upon corresponding movement of said yoke and between such strokes for oscillating said piston 20 upon oscillation of said yoke IS. The pins 52 are arranged on said cam member 42 so that two of them, the upper and lower ones, lie on the axis of reciprocation and oscillation of said cam member 2, the rotary cam 62 being successively engageable (starting with the parts as positioned in Fig. 5) with the left-hand pin 52 to oscillate the cam 62 and the piston 23 so as to align the port 78 thereof with the intake port It; thence with the top pin to effect the suction stroke of the piston; thence with the right-hand pin 52 to oscillate the cam member 42 and the piston 28 to align the piston port with the discharge port 32; and thence with the bottom pin 52 to effect the discharge stroke of the piston.

While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification and I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes and alterations which fall within the purview of the following claims.

I claim:

1. A pump comprising a cylinder closed at one end and having spaced inlet and discharge ports spaced from the closed end of said cylinder, a reciprocable piston operatively arranged in said cylinder and having a port in its side and a duct extending between said port and the working face of said piston, and common means for reciproeating said piston in said cylinder and for rotating said piston to align the port therein with said inlet port at the beginning of the suction stroke of the piston and to align said port in said piston with said outlet port at the beginning of the discharge stroke of the piston, said means comprising a rotary cam, a yoke including a cam member having four pins arranged parallel to each other in a circle ninety degrees apart with the axis of said pins normal to said circle, said cam member being positioned relative to said rotary cam so that said cam upon rotation thereof will successively engage. said pins, means for mounting said yoke for oscillation about its longitudinal axis and for reciprocating movement parallel to said axis, said yoke being connected to said piston for effecting the reciprocation thereof, said pins being arranged on said cam member so that two of them lie on the axis of oscillation and reciprocation of said yoke, said rotary cam being engageable with said two pins to effect the suction and discharge strokes of said piston and with the other two pins to oscillate said cam member about said axis between said strokes so as to position said piston port in line with said inlet port before and during the suction stroke of the piston and in line with said outlet port before and during the discharge stroke of said piston.

2. A pump comprising a cylinder member closed at one end and having spaced inlet and discharge ports spaced from the closed end thereof, a reciprocable piston member operatively arranged in said cylinder member and having a port in its side and a duct extending between said 'port and the working face of said piston member, and means for reciprocating and rotating one of said members relative to the other to effect a pumping action, said means comprising a rotary cam, a yoke including a cam member having four pins arranged parallel to each other in a circle ninety degrees apart with the axis of said pins normal to said circle, said cam memher being positioned relative to said rotary cam so that said cam upon rotation thereof will suecessively engage said pins, means for mounting said yoke for oscillation about its longitudinal axis and for reciprocating movement parallel to said axis, said yoke being connected to one of said piston and cylinder members for effecting the reciprocation thereof relative to the other, said pins being arranged on said cam member so that two of them lie on the axis of oscillation and reciprocation of said yoke, said rotary cam being engageable with said two pins to effect the suction and discharge strokes of said pump and with the other two pins to oscillate said cam member about said axis between said strokes so as to position said piston member port in line with said inlet port before and during the suction stroke of the pump and in line with said outlet port before and during the discharge stroke of said pump.

3. A pump comprising a cylinder member closed at one end and having spaced inlet and discharge ports spaced from the closed end thereof, a reciprocable piston member operatively arranged in said cylinder member and having a port in its side and a duct extending between said port and the closed end of said cylinder member, and means for reciprocating and for rotating said members relative to each other to efiect a pumping action, said means comprising a rotary cam, a yoke including a cam member having four surfaces arranged parallel to each other in a circle ninety degrees apart and normal to said circle, said cam member being positioned relative to said otary cam so that said cam will successively engage said surfaces, means for mounting said yoke for oscillation about its longitudinal axis and for reciprocating movement parallel to said axis, said yoke being connected to one of said piston and cylinder members for eifecting the reciprocation thereof relative to the other, said surfaces being arranged on said cam member so that two of them lie on the axis of oscillation and reciprocation of said yoke, said rotary cam being successively engageable with said two surfaces to effeet the suction and discharge strokes of the pump and with the other two surfaces to oscillate said cam member about said axis between said strokes so as to position said piston member port in line with said inlet port before and during the suction stroke of the pump and in line with said outlet port before and during the discharge stroke of said pump.

4. A pump comprising a cylinder member closed at one end and having spaced inlet and discharge ports spaced from the closed end of said cylinder member, a reciprocable piston member operatively arranged in said cylinder member and having a port in its side and a duct extending between said port and the working face of said piston member, means for reciprocating one of said members relative to the other to effect a pumping action, and means synchronized with said reciprocating means for rotating one of said members relative to the other to align the port in said piston member with said inlet port during the suction stroke of the pump and to align said port in said piston member with said outlet port during the discharge stroke of said pump, said rotating means comprising a toothed member slidably and non-rotatably connected to said reciprocating means and teeth on one of said pis ton and cylinder members meshing with said toothed member and means for rotating said 7 toothed. member a predetermined amount only between the strokes of the pump.

5. A. pump comprising a cylinder closed at one end and having spaced. inlet and discharge ports spaced. from the closed end of said cylinder, a reciprocable piston. operatively arranged in said cylinder and having. a port in its side and a duct extending. between said port and the working face of said piston, and means for reciprocating and rotating said piston to effect a pumping action, said. means comprising a rotary cam,. a yoke ineluding a cam member having four" surfaces arranged. parallel to each other in a circle ninety degrees apart with sald surfaces normal to said circle, said cam member being. positioned relative to said. rotary cam so that said cam upon. rotation thereof will. successively engage said surfaces, a rotary hub slidably and non-rotatably mounting said yoke for oscillation about its longitudinal axis and for reciprocating movement parallel to said axis, said yoke being connected to said piston for effecting the reciprocation thereof, and said. hub. being. connected to said piston for effecting the rotation thereof, said surfaces being arranged on said cam member so that two of them lie on. the aXis: of oscillation and reciprocation of said yoke, said rotary cam being, engageable with said two surfaces to effect the, suction and discharge strokes of said. piston and with the other two surfaces to oscillate said cam member about said axis between. said. strokes so as, to position said piston port in line with said inlet port before and. during the suction stroke of the piston and in line with said. outlet port before and during the discharge stroke of said piston.

RALPH F. URSO.

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

UNITED STATES PATENTS Number Name Date 1,744,791 Nemetz Jan. 28, 1930 FOREIGN PATENTS Number Country Date 550,753 Germany 1933

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