US3527550A

US3527550A - Adjustable stroke reciprocating pump

Info

Publication number: US3527550A
Application number: US785903A
Authority: US
Inventors: Jac Flynn; Werner K Priese
Original assignee: Hills Maccanna Co
Current assignee: DURION COMPANY Inc
Priority date: 1968-12-23
Filing date: 1968-12-23
Publication date: 1970-09-08
Anticipated expiration: 1987-09-08
Also published as: GB1285089A

Description

Sept. 8, 1970 J. FLYNN ET AL 3,527,550

ADJUSTABLE STROKE RECIPROCATING PUMP Filed Dec. 23, 1968 5 Sheets-Sheet 1 186' 2 LZnz/enfifi'a' 185 126 130 66 120 i qqc 51 1177/ 33 Qflrner ltpr z'esa Sept. 8, 1970 J. FLYNN ET AL ADJUSTABLE STROKE REGIPROCATING PUMP 5 Sheets-Sheet 2 Filed Dec. 23, 1968 QM mm HON NW Sept. 8, 1970 J. FLYNN ET AL ,527,550

v ADJUSTABLE STROKE RECIPROCATING PUMP Filed Dec. 23, 1968 5 Sheets-Sheet :3

nveuforscu: Q g b Sept. 8, 1970 I J, FLYNN ET AL 3,527,550

ADJUSTABLE STROKE RECIPROCATING PUMP Filed Dec. 25, 1968 5 Sheets-Sheet 4 Q I 9 1m wrne iif gese Sept. 8, 1970 J. FLYNN ET AL 3,527,550

ADJUSTABLE STROKE RECIPROCATING PUMP Filed Dec. 25, 1968 5 Sheets-Sheet E) jmejflazs Ja g 1177/ erner ff. 3 911258 Q? United States Patent 3,527,550 ADJUSTABLE STROKE RECIPROCATING PUMP Jac Flynn, Elgin, and Werner K. Priese, Barrington, Ill., assignors to Hills-McCanna Company, Carpentersville, 111., a corporation of Delaware Filed Dec. 23, 1968, Ser. No. 785,903 Int. Cl. F04]: 49/00, 43/00 U.S. Cl. 103383 15 Claims ABSTRACT OF THE DISCLOSURE A controlled volume metering pump utilizing reciprocable pumping means to pump liquids at pumping rates that are precisely accurate even at high pressures and adjustably variable under precise, accurate control from zero to maximum pumping capacity by adjustment of the pumping stroke. The avoidance of force reversals on the pumping mechanism during output strokes is achieved and the capability is afforded for pumping liquid at a volumetric rate that is precisely accurate, even for high output pressures, at all rate settings, including those that are very low in relation to maximum output capacity, by an improved crosshead, adjustable trunnion, and power lever construction that assures movement of the pumping plunger to its maximum forward position for all degrees of adjustment of the pumping stroke thereby affording the additional advantage of avoiding encrustment of pumping plunger slide surfaces even though the pump is operated indefinitely at reduced output rates. Pumping plungers are reciprocated by crossheads driven by an oscillating power lever through trunnions operatively engaging transverse actuating tracks on the respective crossheads and being adjustable along support tracks on the lever that are parallel to the actuating tracks on each crosshead when the power lever is in its corresponding full forward position. A strong, compact, and wear resistant construction is provided by crossheads slidably supported by wear resistant bearings and interleafed between legs of a pivoted power lever interconnected with the crossheads by wear resistant, adjustable trunnion units and oscillated by an underlying slide block orbited in oil in driving engagement with a lower slot in the lever. The load of working force on each trunnion unit is divided into two equal parts and carried by opposite ends of the trunnion unit, which has a medial swivel support on the power lever, with the consequence that bending loads on the parts are eliminated and minimized to advantage.

DISCLOSURE The present invention relates to adjustable stroke reciprocating pumps.

One object of the invention is to provide for pumping fluids to very high output pressures, if desired, an adjustable stroke reciprocating pump that provides for controlled adjustment of the output rate of the pump from a zero value to the maximum pumping capacity of the pump through adjustment of the operating stroke of the pump in a manner which effectively minimizes, for all degrees of pump adjustment, loss of pumping effectiveness due to fluid compression even at high pressures, which aids in the pumping of slurry materials by effecting maximum scavaging of pump chamber space for all degrees of stroke adjustment and which minimizes the possibility of vapor lock.

ice

A more specific object is to provide an improved, adjustable stroke pump of the character recited having a construction that provides for progressive adjustment of the pump stroke from a zero value to a maximum value in a manner that assures movement of the pumping plunger to a maximum forward position during each operating cycle, which forward position is the same for all degrees of adjustment of the pumping stroke.

A related object is to provide an adjustable stroke pump as recited in which force reversals on the pumping mechanism during individual output strokes are obviated.

A more particular object of the invention is to provide an adjustable displacement pump of the character recited which makes use of a fluid actuated diaphragm to pump corrosive liquids with new advantages at high pressures and at exceptionally low rates, in relation to maximum capacity, that can be controlled adjustably with precision by adjustment of the effective displacement of the pump.

Another object is to provide an adjustable stroke reciprocating pump utilizing strong mechanical forces to pump fluid to high pressures and having strong working components interrelated with each other to provide a compact working assembly minimizing the size of the pump while at the same time achieving a striking resistance to wear of the parts through distribution of operating forces transmitted between working parts over ex tensive bearing surfaces with the consequence that a long service life is achieved.

A further object is to provide an adjustable stroke pump as recited having an improved construction which transmits powerful mechanical working forces through a compact operating assembly that provides for ready adjustment of the pumping stroke with precision while at the same time avoiding high stresses on the mechanism.

Another object is to provide an adjustable stroke pump of the character set forth in which oscillatory movements of a power drive lever are translated into reciprocatory pumping movements by a trunnion unit coacting with a translatable crosshead and adjustably supported on the power lever in such manner that the working load on the power drive lever is centrally alined with reference to the lever structure receiving the load with the consequence that torsional loads on the parts are eliminated or minimized to advantage.

A further object is to provide an improved adjustable stroke pump as recited in the preceding objects that further provides for optional pumping of two separate fluid mediums simultaneously using two pumping plungers having pumping strokes individually adjustable in accordance with the invention.

Another object is to provide an improved pump as recited in the preceding objects in which driving components of the pumping mechanism have a relative orientation which facilitates lubrication of the working parts to advantage by an oil bath.

A further object is to provide a reciprocating pump according to the preceding objects having an improved construction that enables the pump to contain to great advantage at least two different working fluids, including a fluid lubricant, that function in contact with adjacent portions of reciprocating components of the pumping mechanism while being maintained continuously in perfect isolation from each other so that the purity and effectiveness 3 of each fluid is fully preserved with no contamination of either fluid by the other.

Still another object is to provide an adjustable stroke pump according to the preceding objects which is inherently well adapted to allow optional installation of a plurality of pumping units in mutual juxaposition for advantageous energization by a common drive.

Other objects and advantages will become apparent from the following description of the exemplary embodiment of the invention illustrated in the drawings, in which:

FIG. 1 is a perspective view of a dual pump embodying the invention;

FIG. 2 is a simplified side view on a reduced scale illustrating mounting of two dual pumps alongside each other for energization by a common motor drive unit illustrated schematically;

FIG. 3 is a longitudinal sectional view on an enlarged scale of the pump of FIG. 1, taken generally with reference to the irregular line 33 of FIG.

FIG. 4 is a fragmentary transverse sectional view on a still larger scale taken generally with reference to the line 44 in FIG. 3, certain components being shown in elevation for clearness in illustration;

FIG. 5 is a somewhat simplified horizontal sectional view taken generally with reference to the irregular line 55 in FIG. 3;

FIG. 6 is a fragmentary sectional view taken with reference to the line 66 in FIG. 4 and showing a side view of a crosshead support bearing unit mounted in a crosshead and slidably engaging a crosshead support bar;

FIG. 7 is a perspective view showing crossheads slidably supported in juxtaposition on parallel support bars in conjunction with adjustable trunnion units;

FIG. 8 is a simplified sectional view taken generally with reference to the line 8-8 of FIG. 4 and showing the full stroke position of adjustment of one trunnion unit in relation to the coacting crosshead and power drive lever, the crosshead being illustrated in its fully advanced position in FIG. 8;

FIG. 9 is a view similar to FIG. 8 but showing the relationship of the parts when the crosshead is in its fully retracted position;

FIG. 10 is a view similar to FIG. 8 but showing the trunnion unit, which transmits motion between the power lever and a coacting crosshead, adjusted to its zero stroke position;

FIG. 11 is a view similar to FIG. 10 but illustrating the relationship of the parts when the power lever is swung to an extreme position opposite from that illustrated in FIG. 10;

FIG. 12 is a fragmentary, exploded perspective view on an enlarged scale showing an adjustable trunnion block, coacting trunnion bearings, and adjacent working components of the power drive lever along which the trunnion block is adjusted by a screw, shown in phantom, and showing adjacent components of the coacting crosshead receiving the trunnion bearings;

FIG. 13 is a fragmentary perspective view on an enlarged scale of the outboard side of one end of a crosshead showing a crosshead support bearing rotatably mounted in the crosshead in alinement with a coacting support bar;

FIG. 14 is a side elevational view on an enlarged scale of the power drive lever, partially sectioned at the lower end to reveal the actuating slide block in engagement with the transverse actuating track in the lower end of the lever; and

FIG. 15 is an enlarged detailed sectional view corresponding to the left central portion of FIG. 3 and showing the sealed mechanism which assures isolation of different fluids contained in the pump.

Referring to the drawings in greater detail, the adjustable stroke dual pump forming the exemplary embodiment of the invention illustrated in FIG. 1 comprises a fluid actuated diaphragm pumping unit or head 22 and a reciprocable plunger pumping unit or head 24, both designed to pump fluid to high pressures, supported on opposite sides of the upper portion of a central housing 26.

The high pressure pumping head 22 is designed to pump corrosive fluids and comprises, as illustrated in FIGS. 1 and 3, an inlet check valve 28 through which fluid to be pumped is admitted into a pumping chamber 30 from which the pumped fluid is discharged through an outlet check valve 32. The pumping chamber 39 communicates through a multiplicity of openings 34 with a circular diaphragm chamber 36 containing a flexible pumping diaphragm 38 clamped along its marginal edge and being flexibly movable between concave opposite sides of the diaphragm chamber 36.

The pumping diaphragm 38 is flexed back and forth in the chamber 36, to effect pumping, by an operating fluid medium pumped alternately into and out of the diaphragm chamber 36 through a multiplicity of openings 40 into the chamber 36 on the side of the diaphragm 38 opposite from the openings 34. Such operating fluid medium is alternately forced through the openings 40 into the diaphragm chamber 36 and withdrawn from the chamber 36 through the openings 40 by reciprocation of a pumping plunger or piston 42 slidable within a cylinder 44 communicating with the openings 40.

The other pumping unit 24 comprises, as shown in FIG. 3, an inlet valve 46 and an outlet valve 48 communicating with a pumping chamber 50 into which projects reciprocably the forward end of a pumping plunger 52 encircled inwardly of the pumping chamber 50 by a high pressure packing 54.

The plunger 42 of the high pressure diaphragm pumping unit 22 and the plunger 52 of the high pressure plunger pumping unit 24 are connected respectively, as shown in FIGS. 3 and 5, with two juxtaposed

crossheads

56, 58 slidably supported within the upper portion of the housing 26 in an advantageous manner to be described and having an interleafed relationship with two spaced parallel

pivot support legs

60, 62 of a common drive lever indicated generally by the number 64 and sometimes referred to as a swingable hanger bracket.

The drive lever 64, which can be advantageously visualized as being a power operated drive pendulum, comprises the two

spaced support legs

60, 62, previously mentioned, extending vertically between an upper cross member 66 and a lower cross member 68, FIGS. 4 and 14, of the drive lever 64 to which the pivot support legs are integrally connected.

The swingable drive lever or pendulum 64 thus formed of two spaced parallel

pivot support legs

60, 62 extending vertically between the upper and

lower cross members

66, 68 is pivotally supported for swinging movement about a horizontal pivot axis 70, FIGS. 4, 8 to 11 and 14, by two antifriction bearings 72, 74 supported respectively on two

stub axles

76, 78 projecting inwardly into the housing 26. The

stub axles

76, 78 are removably supported in

support apertures

80, 82 in the

opposite sidewalls

84, 86 of the housing 26 and held in place by cap screws 88 as shown in FIG. 4. The housing 26 includes a removable cover 90.

The drive lever or pendulum 64 is power driven to oscillate back and forth by power drive means which minimizes the overall size of the mechanism while at the same time facilitating lubrication of the working parts by an oil bath.

More particularly, the drive lever 64 is power oscillated back and forth by a rotary driver 92 located below the drive lever 64, as shown in FIG. 3, and journalled in the lower portion of the housing 26 by

suitable antifriction bearings

94, 96 for rotation about a vertical axis 98 that intersects, as indicated in FIGS. 4, 10, 11 and 14, the pivotal axis 70 of the lever 64.

In the preferred construction illustrated, the rotary driver 92 is formed by a worm wheel (also denoted by the number 92) meshing with a horizontal drive worm 100 forming a component part of a horizontal drive shaft 102,

FIGS. 2 and 3, journalled by suitable bearings 104 in the lower portion of the housing 26.

The lower portion of the swingable drive lever 64 includes means defining a generally linear drive track 106, FIGS. 3, 10, 11 and 14, substantially parallel to the pivot axis 70 of the drive lever. The linear drive track 106 is swung in an arcuate path by an actuator indicated generally by the number 108 in FIG. 3 carried by the rotary driver 92 in radially offset relation to the axis 98 of the driver 92 and coacting with the track 106 to provide for rotation of the swingable drive lever 64 and the rotary driver 92 in relation to each other about an axis 110, FIGS. 3, 10, 11 and 14, that is fixed in relation to the rotary driver 92 and oriented in relation to the rotary driver 92 to have a common intersection with the axis 98 of the rotary driver 92 and the pivotal axis 70 of the swingable lever 64 for all rotary positions of the driver 92. That is, all three

axes

70, 98 and 110 mutually intersect at a common point of intersection, continuousl for all rotary positions of the driver 92 and all angular positions of the lever 64, FIGS. 3, 10, 11 and 14.

The linear drive track 106 on the lower portion of the swingable lever 64 is formed structurally by a straight drive slot (also denoted by the number 106) formed in the lower cross member 68 of the lever 64 and opening downwardly in symmetrical relation to a swingable central plane 112 containing the pivotal axis 70, FIGS. 3, 10, 11 and 14, and also containing, as will presently appear, the axis 110.

The drive track or slot 106 slidably receives a slide block 114, FIGS. 3, 8, 9 and 14, forming a part of the previously mentioned actuator 108 and being rotatably journalled on a stub axle 116, also forming a part of the actuator 108. The stub axle 116 is fixed to the rotary driver 92 for rotation with the driver 92 in radially offset relation to the axis 98. The axis about which the sliding block 114 rotates in relation to the stub axle 116 constitutes the previously mentioned axis 110, the stub axle 116 being oriented on the rotary driver 92 so that the axis 110 of the stub axle 116 extends continuously through the intersection of the lever axis 70 and the rotary driver axis 98. Thus, upon rotation of the rotary driver 92, the slid ing block 114 moves back and forth in the slot or track 106 to cause the lever 64 to oscillate about its pivotal axis 70. During such rotation of the rotary driver 92, the axis 110 about which the sliding block 114 rotates in relation to the rotary driver 92 moves through a conical path, the apex of which remains stationary and coincides with the intersection of the pivotal axis 70 of the lever 64 and the rotary axis 98 of the driver 92.

The

crossheads

56, 58 designed to embrace the spaced parallel

pivot support legs

60, 62 of the drive lever 64 are formed individually to have a generally U-shape as viewed from above, FIGS. and 7. The two

crossheads

56, 58, thus formed, are slidably supported for translation independently of each other on three parallel crosshead support bars 120, 122, 124 removably mounted in spaced parallel relation to each other in the upper portion of the housing 26.

In the preferred construction shown, the crosshead support bar 120, for example, is supported at opposite ends by two cap-

like end brackets

126, 128, FIGS. 5 and 7, removably fitted into

support openings

130, 132 in the housing 26 as shown in FIGS. 5 and 7. More particularly, the two

bracket caps

126, 128 are extended from the outside into the

housing openings

130, 132 to receive and support opposite ends of the crosshead support bar 120 and are releasably held in place by externally accessible screws 134 extending through the cap brackets into the housing. The crosshead support bars 122 and 124 are similarly mounted removably in the housing 26 by

cap brackets

136 and 138.

Each of the crosshead support bars 120, 122 and 124 is essentially square in transverse section and provides slidable support to the adjacent side of each adjacent crosshead, the central support bar 122 serving to support the adjacent sides of both

crossheads

56, 58 disposed on opposite sides of the central support bar 122 as illustrated in FIGS. 5 and 7. Moreover, each of the crosshead support bars extends into a medial longitudinal groove 140 formed in the adjacent side of each adjacent crosshead, as illustrated in FIGS. 4, 7 and 13, to accommodate the support Each crosshead is shaped at each end of each crosshead groove 140 in the crosshead to receive and support rotatably a bearing unit 141, FIGS. 6 and 13, specially designed to slidably support the corresponding crosshead on the coacting support bar 120, FIG. 13, while being selfadjusting to eliminate stress concentrations on the surfaces which support the crosshead and slide in relation to each other upon translation of the crosshead.

As best shown in FIGS. 6 and 13, each crosshead support bearing unit 141 has the overall form of a circular disc, modified as will be described. Each disc-like bearing unit 141 fits rotatably Within a corresponding bearing support Well 148 of cylindrical shape machined in the crosshead in transverse alinement with the corresponding crosshead groove 140 as shown in FIG. 13 and having a diameter materially greater than the corresponding transverse dimension of the groove 140. Each bearing unit 141 has a thickness exceeding substantially the depth of the corresponding groove 140 and the well 148 in which the bearing 141 fits rotatably has a corresponding depth to accommodate the bearing unit.

The outboard face of each bearing unit 141 is centrally channeled as illustrated in FIG. 13 to slidably receive an adjacent side portion of the corresponding support bar. In this manner the bearing unit 141 is fashioned to define on opposite sides of an intervening support bar 120, FIG. 13, two mutually confronting bearing elements 142 shaped individually in the form of segments of a circle and integrally connected together by a base portion 143 of the bearing 141 disposed alongside the support bar and accommodated rotatably in the inner portion of the circular bearing receiving well 148.

Each of the two bearing elements 142 embracing opposite sides of the intervening support bar 120, with reference to FIGS. 6 and 13, defines a straight bearing surface 144 slidably engaging the adjacent surface of the rectilinear support bar 120. The outer peripheries of the bearing elements 142 and the ajoining portions of the connecting base portion 143 of each bearing 141 are formed by arcuate segments of a peripheral surface 146 of cylindrical curvature formed on the bearing and fitting slidably within the corresponding bearing support well 148.

Thus supported rotatably within the corresponding crosshead well 148, each bearing 141 is free to turn rotatably about the common axes of the well 148 and the peripheral bearing surface 146 to continuously maintain an unstrained parallel relationship between the straight hearing surface 144 and the support bar on which the bearing slides. As a consequence, the crosshead forces applied to the support bar by each bearing 141 are evenly distributed along the full length of the bearing surfaces 144 alternately throughout the life of the mechanism so that stress concentrations on the crosshead support surfaces which slide in relation to each other are avoided and a long service life is obtained.

To facilitate location of the rotatable bearings 141 adjacent the extreme ends of the corresponding crosshead grooves as shown without substantial extension of the bearing structure beyond the crosshead, the base portion 143 of each bearing is truncated along opposite side edges as illustrated in FIG. 13 to have a width along the corresponding groove 140 equal to the corresponding dimension in the same direction of the straight bearing surface 144 on the bearing elements 142.

It will be appreciated that four of the rotary bearings 141 constructed and supported as described are used to support each of the

crossheads

56, 58. To provide interchangeability of parts, all of the bearings 141 are similar in construction. Moreover, the two bearing elements 142 of each bearing 141 are dimensioned and positioned laterally with respect to the intervening support bar so that each straight bearing surface 144 extends laterally across somewhat less than half of the corresponding width of the support bar surface slidably engaged by the bearing surface thus providing for accommodation on the central support bar 122 of the adjacent bearings 141 on both the

adjacent crossheads

56, 58. Consequently, the adjacent bearings on the two crossheads can move past each other along the intervening support bar 122 without interference.

Oscillatory movement of the power driving lever or pendulum 64 is translated into reciprocating movement of the

translatable crossheads

56, 58 through adjustable pivots carried by the respective

pivot support legs

60, 62 and coacting with the respective crossheads to provide for adjustment of the stroke of each crosshead while at the same time providing for movement of the crosshead during its operating cycle to an extreme forward position which is the same for all degrees of stroke adjustment of the crosshead, FIGS. 3, 8, 9, 10, 11 and 12.

For this purpose, each of the

pivot support legs

60, 62 of the drive lever 64 carries a pair of crosshead actuating trunnions 150 supported on the corresponding leg for adjustment along the leg in a manner to be described and constituting an adjustable pivot.

As shown in FIGS. 3, and 12, the two trunnions 150 for each crosshead are formed by projections on opposite ends of a trunnion block 152 supported on the lever leg 60, for example, for adjustable translation along a trunnion or pivot support track 154 formed on the lever leg. More particularly, the trunnion or pivot support track 154 is formed by a straight slot (also denoted by the number 154), FIGS. 3 and 12, defined in the lever leg 60, for example, to extend through the lever leg 60 from the vicinity of the lower cross member 68, FIGS. 3 and 4, out through the top of the lever 64. Opposite

edges

155, 157 of the track defining slot 154 are concave in transverse section, FIG. 5, and receive slidably two slide bearing surfaces 156, 158 formed by opposite sides of the trunnion block 152. Preferably, the two bearing

surfaces

156, 158 on the trunnion block 152 and the two

track edges

155, 157 slidably engaged by the block edges 156, 158 have a common axis of transverse curvature and substantially equal radii of curvature so that the trunnion block is free to rotate or swivel about the axis of its supporting track 154 on the lever 64.

The trunnion block 152 is centrally threaded to receive a threaded adjusting screw 162, FIGS. 3, 4, 7 and 12, journalled in the drive lever or pendulum 64 for swinging movement with the drive lever 64 in a position which remains stationary in relation to the lever 64 except when the screw 162 is rotated to effect adjustment of the trunnions 150 along the track 154. Rotary support for the screw 162 on the lever 64 is provided by a ball bearing 166, capable of sustaining both radial and thrust loads, fitted in an enlargement 168 of the upper end of the trunnion support slot 154 in the drive lever 64 as shown in FIG. 4 and engaging a funnel-shaped extension 170 on the upper end of the screw 162. The lower end of the screw 162 is guided rotatably within the lower portion of the lever 64 by a cylindrical extension 172 of the lower end of the screw 162 fitting rotatably within a cylindrical bore 174 extending into the lever 64 downwardly from the slot 154, as shown in FIG. 4.

The screw 162 is adjustably rotated to translate the trunnion block 152 adjustably along the support track 154 by a rotary, stroke adjusting handle 176 rotatably journalled on the housing cover 90 and connected to the screw 162 through an adjusting shaft 178 having a universal joint connection with the rotary screw 162 and a universal joint connection with the handle 176 which permits the handle 176 to remain stationary while the screw 162 swings with the drive lever 64 in which the screw is mounted. Any tendency the screw 162 might otherwise have to rotate under the influence of substantial working force components applied axially to the screw by the trunnion block 152 during operation of the pump is effectively overcome by limiting the lead of the screw sufiiciently to reduce the torque tending to rotate the screw below the frictional resistance to screw rotation.

A visual indicator 180, FIGS. 1 and 3, geared to the handle 176 functions to provide a visual indication of the degree of stroke adjustment of the pumping head corresponding to the adjusting handle. As shown in FIGS. 1 and 3, the indicator 180 is mounted outside the housing 26 and is connected to the handle 176 outside the housing so that the indicator remains clear and free of fogging at all times.

The two trunnions 150 on the adjustable trunnion block 152 project in opposite directions as indicated and support respectively two

trunnion bearings

182, 184, FIGS. 4 and 12, rotatable on the trunnions 150 and slidably disposed within two actuating

tracks

186, 188 formed in the embracing crosshead 56 in transverse relation to the direction of translation of the crosshead as defined by the coacting crosshead support bars 120, 122. The two actuating

tracks

186, 188 are formed, as shown, by parallel slots (also denoted by the numbers 186, 188) formed in the crosshead 56, for example, in confronting relation to the intervening pivot or trunnion support leg of the lever 64. The

trunnion bearings

182, 184 have close sliding fits within the respective slot tracks 186, 188. By virtue of the trunnion block 152 being centrally supported in the manner described on the lever leg 60, the crosshead forces applied to the two trunnions 150 are continuously balanced. The tendency which the crosshead force applied to each trunnion 150 has to turn the trunnion block 152 within its support track 154 is offset .by an equal crosshead force on the other trunnion with consequent minimization of stress on the parts.

As shown in FIG. 3, the translatable crosshead 56 is detachably connected to the piston 42 of the pumping head 22 by a translatable extension rod 190 threaded into the unbifurcated end of the crosshead 56 and detachably connected to the piston 42 by a self-alining separable coupling 192. The crosshead 58 is similarly connected to the pumping plunger 52 of the pumping head 24 by a translatable extension rod 194 and a separable coupling 196.

The pivot supporting track slot 154 is oriented within the pivot support leg 60 and the movable trunnion block 152 is dimensioned so that adjustable movement of the trunnion support block 152 by the adjusting screw 162 to the upper zero stroke position illustrated in FIGS. 10 and 11 brings the trunnions 150 into coaxial alinement with the pivotal axis of the swingable drive lever 64.

When the trunnions are adjusted to this position of coaxial alinement with the pivotal axis 70 of the drive lever 64, swinging movement of the drive lever 64 merely causes the trunnions 150 to rotate in place without effecting any displacement of the pumping piston 42 connected to the crosshead 56 engaged by the trunnions 150. It will be appreciated that the pumping action of the pumping head 22 can be stopped by adjusting the actuating trunnions 150 for the pumping head 22 to their zero position lilustrated in FIGS. 10 and 11 while the oscillating lever 64 works to continue operating the pumping head 24, the stroke of which can be independently adjusted in the same manner as will presently appear. With reference to the condition of the pump as illustrated in FIGS. 3 and 5, the pumping head 24 is adjusted to zero displacement.

Progressive displacement of the trunnion block 152 from its zero position in a downward direction along the track groove 154 toward its full stroke position illustrated in FIGS. 8 and 9 by rotation of the adjusting screw 162 effects a corresponding progressive increase in the stroke of the pumping piston 42 actuated by the crosshead 56. The stroke of the pumping piston 42 has a length directly proportional to the degree to which the corresponding trunnions 150 are displaced radially out of coaxial alinement with the pivotal axis 70 of the oscillating drive lever 64.

As previously intimated, the mechanism is so designed that the pumping piston 42 of the pumping head 22, for example, is always moved during its operating cycle to an extreme forward position which is the same for all degrees of stroke adjustment of the piston 42. For this purpose, the pivot supporting track groove 154 in the oscillating power lever 64 is oriented in relation to the lever 64, the uniform angular range of movement of the lever 64 and the crosshead 56 so that when the pivot support leg 60 corresponding to the pumping piston 42 is in its extreme forward position, as shown in FIGS. 3, 8 and 10, the pivot support track groove 154 is parallel to the trunnion receiving

track grooves

186, 188 formed in the crosshead 56 and receiving the trunnions 150. As a consequence, adjustable displacement of the trunnions 150 along the trunnion supporting track groove 154 to either the zero stroke position illustrated in FIG. 10 or the full stroke position illustrated in FIG. 8 or to any intermediate position therebetween does not change the location of the forwardmost position of the crosshead 56 or the corresponding forwardmost position of the pumping piston 42.

Progressive adjustment of the trunnions 150 from the zero stroke position illustrated in FIGS. 10 and 11 toward the full stroke position illustrated in FIGS. 8 and 9 does progressively increase the length of the stroke of the pumping piston 42 by changing the fully retracted position of the pumping piston 42 without disturbing the location of the full forward position to which the piston 42 is moved during each operating cycle.

By virtue of the fact that the pumping piston 42 is advanced during each operating cycle to a full forward position which is the same for all degrees of stroke adjustment, the quantity of the operating fluid medium contained within the space for diaphragm actuating fluid provided within the pumping head 22 and existing functionally between the high pressure end of the pumping piston 42 and the adjacent side of the flexible diaphragm 38 can be minimized to the bare minimum quantity required for actuating the diaphragm. As a consequence of this minimization of the quantity of operating fluid required for actuating the diaphragm 38 as an incident to reciprocation of the piston 42, the degree of volumetric compressibility of the fluid during a pumping stroke is minimized to a most significant degree with the consequence that the pumping head 22 can function reliably to pump fluid to a high pressure at very low rates that can be accurately predetermined adjustably. The operating fluid medium intermittently pressurized by the piston 42 to actuate the diaphragm 38 has a certain inevitable degree of compressibility due to the presence of gas entrained in the liquid forming this fluid medium.

Further, as a consequence of the pumping piston 42 moving to its full forward position once during each stroke for all degrees of stroke adjustment, the pump has a high degree of immunity from operational problems caused by vapor lock. The high degree to which the pumping space is emptied with assurance once during each pumping cycle minimizes the quantity of fluid left in the pumping space at the end of a pumping stroke with consequent minimization of related functional problems, such as fluid compressibility and vapor lock.

The same considerations apply to operation of the reciprocable pumping plunger 52 of the pumping head 24 which is, for all degrees of adjustment of the stroke of the pumping plunger 52, advanced during each operating cycle to a predetermined maximum degree with the consequent expulsion of a maximum quantity of liquid from the pumping chamber 50. This, too, makes for a highly advantageous operability of the mechanism to pump fluid particularly at high pressures and at very low rates in relation to maximum capacity.

As a consequence of its being advanced to its maximum forward position during each operating cycle even when moving through its shortest strokes, the surfaces of the plunger 52 which slide within the encircling structure of the pumping head 24 and which are retracted inwardly during a pumping cycle are kept clean and free of encrusting materials even though the pump may be operated indefinitely at a reduced stroke setting.

The described construction provided for reciprocating the crosshead 56 and adjusting the length of stroke of the pumping piston 42 is duplicated in relation to actuation of the crosshead 58 by the drive lever 64 and adjustment of the stroke of the plunger 52 as previously intimated. Components of the structure used to actuate and adjust the strokes of the crosshead 58 corresponding to those used in actuating and controlling the crosshead 56 are identified with the same reference numbers with the addition of the suffix a.

The housing 26 is well adapted to contain in its lower portion a large quantity of lubricating oil immersing the lower portion of the pump mechanism and serving effectively to continuously lubricate the entire mechanism. Sealing of the rotary drive shaft 102 against the escape of lubricant along the shaft presents no difliculty to those skilled in the art.

As the housing 26 has the capacity to contain a large quantity of lubricating oil, the escape of a small quantity of such oil along the drive shaft 102 to the external environment may not necessarily be a serious matter, the supply of lubricating oil being replenished periodically as necessary. On the other hand, contamination of the lubricating oil contained within the housing 26 by other fluids can be most serious indeed.

The compact drive mechanism of the pump contained within the housing 26 includes the coacting worm and worm gear 92 which require lubrication by a special high pressure lubricant. A lubricating fluid adapted for this special purpose is used to fill the housing 26 to a desired level.

The problem of avoiding contamination of the special lubricating fluid contained within the housing 26 is severely complicated by the necessity, as a practical matter, of containing within the pump other fluids of a distinctly different character. Moreover, the different fluids function in contact with adjacent portions of reciprocating components of the pump mechanism, thus creating difficulties in maintaining an assured separation of the fluids from each other so that neither is contaminated by the other. Cross contamination of the fluids by co-mingling of either with the other would produce serious operational problems.

Having reference to the drawings, the pump unit 22 comprises a reservoir for hydraulic fluid used in the diaphragm chamber 36, FIG. 3. The other pumping unit 24 comprises a fluid reservoir 187 that may contain to advantage a coolant fluid that cools the plunger 52 working within the packing 54 and any of the pumped fluid that may work its way past the plunger packing 54 from the pumping chamber 50 to the reservoir 187. The

fluid reservoirs

185, 187 are covered respectively by

removable covers

189, 191, FIG. 3, and may be drained by removal of drain plugs 193, 195.

The hydraulic fluid contained in the reservoir 185 to service the diaphragm chamber 36 is in contact with the reciprocating extension rod 190 connected to the reciprocating crosshead 56, which is in direct contact with the lubricating fluid contained within the housing 26 to lubricate the pumping mechanism including the worm 100 and worm gear 92.

The serious consequences of cross contamination of the two different fluids in contact with adjacent portions of the reciprocating structure described and occupying the reservoir 185, and housing 26 are avoided by interconnecting the stationary pump structure intervening between the two fluids with the reciprocating pump structure intervening between the two fluids by a flexible diaphragm 197, FIGS. 3, and 15, of impervious construction encircling the extension rod 190. Similarly, the fluid occupying the reservoir 187 and the fluid occupying the housing 26 are precluded from contaminating each other by a diaphragm 199 encircling the extension rod 194 as will be described.

The sealing diaphragm 197 disposed in encircling relation to the extension rod 190, as illustrated in FIGS. 3 and 15, has an inner periphery that is axially movable in relation to the outer periphery of the diaphragm, as will be described, to accommodate the maximum excursion of the reciprocating extension rod.

In the preferred construction illustrated, the diaphragm 197 is formed of a yieldable polymeric material immune to damage by either of the fluids in which it is in contact. The diaphragm has the overall form of a truncated cone or pyramid and is shaped between its inner and outer peripheries or ends by a continuous series of annular corrugations which maximize, for a diaphragm of any particular overall diameter, the degree of functional axial displacement, relative to each other, of the inner and outer peripheries of the diaphragm that can be utilized in this service to accommodate reciprocation of the extension rod 190.

As shown in FIGS. 3 and 15, the outer periphery of the impervious sealing diaphragm 197 is sealably clamped by a stationary sealing ring 201 to the stationary base 205 of the pumping unit 22 secured firmly to one side of the housing 26. Preferably, an annular bead 210 integral with the sealing diaphragm 197 and constituting its outer periphery is accommodated within an annular groove 212 in the clamping ring 201 and forced into assured sealing engagement with the pumping unit base 205 to which the ring 201 is secured by screws 211, FIG. 15. In this manner, a static leakproof connection between the diaphragm 197 and the pump unit base 205 and housing 26 interposed between the two fluids is assured.

A similar bead 214 of smaller diameter integrally formed on the diaphragm 197 and constituting its inner periphery is forced by an annular shoulder 216, FIG. 15, on the extension rod 190 into an annular groove 218 formed in the crosshead 56 in encircling relation to the extension rod 190 as shown in FIG. 15 to form a static impervious seal between the diaphragm 197 and the juncture of the reciprocating crosshead 56 with the extension rod 190. In this manner, the flexible diaphragm 197 has a static sealed connection with the reciprocating pump mechanism that in practice is invulnerable to leakage just as is the static seal between the outer periphery of the diaphragm and the stationary pump structure.

The other diaphragm 199 is similarly connected to the juncture of the reciprocating crosshead 58 and the extension rod 194 and is similarly clamped to the base 207 of the pumping unit 24, FIG. 5, by a clamp ring 203 to provide an assured separation of the two fluids in the housing 26 and reservoir 187, respectively.

By virtue of the construction described, cross contamination of the lubricating fluid in the housing 26 with the fluids in the

reservoirs

185, 187 is positively precluded by intervening structure of impervious construction including the two

flexible diaphragms

197, 199, each of which has a static, leakproof connection at each end with solid impervious components of the pump structure.

The internal working parts of the pump thus provided are readily accessible for servicing in the event that becomes necessary. The removable cover 90 of the housing 26 with the rotary pump adjusting handles 176, 176a journalled thereon can be released and lifted up to expose the drive lever 64 and the coacting working parts.

Release of the inner mechanism from the housing 26 is effected by retracting the

stub axles

76, 78 which support the drive lever 64, FIG. 4, and withdrawal of the crosshead support bars 120, 122 and 124 after removal of corresponding crosshead support bar caps 126, 128, 136, 138, FIG. 5. Release of the inner mechanism from the pumping

units

22, 24 is effected by disconnection of the couplings 192, 194 and release of the outer peripheries of the sealing

diaphragms

197, 199, which are accessible through the

reservoirs

185, 187 after removal of the reservoir covers 189, 191. The inner mechanism, disconnected from coacting parts in the manner described, can be lifted out through the top of the housing 26 for inspection and service and to provide access to the driving components journalled in the bottom of the housing.

The pump 20 is energized by rotating the drive shaft 102. This can be effected as illustrated schematically in FIG. 2 by means of a motor drive unit 200 connected to the drive shaft 102. If desired, more than one of the pumps 20 can be conveniently mounted in juxtaposition as illustrated in FIG. 2 and driven to advantage by the same motor drive unit 200. Mounting of more than one such pump together to form a battery of pumps energized by a common drive unit is facilitated by covering of one end of the drive shaft 102 by a removable cover 122, FIG. 1, that can be readily removed to allow the drive shaft 102 to be connected by a suitable coupling shaft 204 with the coaxial shaft 102 of an adjacent pump of similar size as illustrated in FIG. 2.

It will be appreciated that the present invention is not necessarily limited to use of the particular construction illustrated and described but includes the use of structural variants within the spirit and scope of the invention as disclosed and defined by the claims which follow.

We claim:

1. An adjustable stroke pump comprising, in combination, a housing, a drive pendulum pivotally mounted in said housing for swinging movement about a pivotal axis and extending downwardly therefrom, means on the lower portion of said pendulum defining a generally linear pendulum drive track, a worm gear journalled in said housing below said pendulum for rotation about an axis that intersects the pivotal axis of the pendulum, a pendulum actuating slide journalled on said worm gear in radially oflset relation to the axis of the worm gear for rotary movement with the worm gear and rotation with respect thereto about an axis oriented to have a common intersection with both said axis of the worm gear and said pivotal axis of the pendulum, a drive worm meshing with said worm gear to rotate the latter, said actuating slide engaging said drive track on said pendulum to oscillate said pendulum upon rotation of said worm gear, a crosshead embracing a medial portion of said pendulum, slide means on said housing supporting said crosshead for reciprocable translation in a direction generally perpendicular to said pivotal axis of the pendulum, said crosshead defining on opposite sides of said medial portion of the pendulum two crosshead actuating tracks generally perpendicular to said direction of translation of the crosshead, said pendulum defining a trunnion support track generally perpendicular to said pivotal axis of said pendulum, trunnion means supported on said trunnion support track for translation thereon and swinging movement therewith, said trunnion means including trunnions projectig in opposite directions, trunnion bearings supported on said trunnions and engaging said crosshead actuating tracks to actuate said crosshead, said trunnion support track having an orientation on said pendulum such that said trunnion support track is parallel to said actuating tracks on said crosshead when said pendulum is swung to its full forward position by said actuating slide on said worm wheel, an adjusting screw journaled in said pendulum in parallel relation to said trunnion support track and coacting with said trunnion means to move the latter adjustably along said trunnion support track, operating means coacting with said adjusting screw to rotate the latter, said trunnion support track on said pendulum being positioned on said pendulum to support said trunnion means in a zero pump stroke position in which said trunnions are in coaxial alinement with said pivotal axis of said pendulum and to support said trunnion means and said trunnions on said pendulum for movement therealong toward or away from said zero pump stroke position upon rotation of said adjusting screw, means on said housing defining a pumping chamber, inlet and outlet valve means communicating with said chamber, and pumping chamber expanding and contracting means including a reciprocable pumping element connected to said crosshead for actuation thereby.

2. An adjustable stroke dual pump comprising, in combination, a housing, an oscillatory power lever pivotally mounted in said housing for swinging movement about a predetermined pivotal axis, said power lever including first and second spaced cross supports generally parallel to said pivotal axis of the power lever and including two pivot support legs extending between said cross supports in spaced generally parallel relation to each other and in generally perpendicular relation to said pivotal axis of said power lever, a pump stroke adjusting pivot movably supported on each of said pivot support legs for rotary movement therewith and adjustable displacement therealong along a predetermined path between a position of coaxial alinement with said power lever pivotal axis and pumping positions radially displaced from said axis, a pump stroke adjusting screw journalled on said power lever and coacting with each of said stroke adjusting pivots to progressively adjust the latter along said predetermined path on the support leg therefor, oscillating means coacting with said power lever to oscillate the latter through a predetermined range of angular movement, two crossheads embracing said respective pivot support legs of said power lever, crosshead support means supporting each of said crossheads for translation reversibly in a predetermined direction, each of said crossheads defining on opposite sides of the intervening pivot support leg two actuating tracks positioned transversely in relation to the direction of translation of the crosshead, said stroke adjusting pivot carried by each support leg comprising two trunnions projecting into coacting engagement with the actuating tracks on the corresponding crosshead, said actuating'tracks on each crosshead being oriented thereon to have a parallel relation to said pre determined path along which the corresponding stroke adjusting pivot is moved in relation to its support leg on said power lever by the coacting adjusting screw when said last mentioned support leg is swung to its extreme forward position by said oscillating means so that the corresponding extreme forward position of the crosshead is not changed by adjustment of the corresponding pivot along the coacting pivot support leg to change the stroke of the crosshead from a zero displacement to a desired displacement, means on said housing defining two pumping chambers, and two reciprocable pumping elements coacting with said respective pumping chambers to pump fluid therethrough and being connected with said respective crossheads for operation thereby.

3. An adjustable stroke multiple pump comprising, in combination, a housing, three crosshead support bars mounted in said housing in parallel spaced relation to each other, a drive lever pivotally mounted in said housing for swinging movement about a pivotal axis and including two generally parallel pivot support legs interleafed between successive support bars, two crossheads embracing said respective pivot support legs, each of said crossheads being slidably supported on the two adjacent support bars for reciprocable translation thereon, each crosshead being supported on each adjacent support bar by two bearings spaced along the bar, each bearing defining two straight bearing surfaces slidably engaging opposite sides of the corresponding support bar, each bearing being supported rotatably on the corresponding crosshead to provide continuously for parallelism between either of the straight bearing surfaces on the bearing and the support bar, said drive lever defining in spaced relation to said pivotal axis thereof a generally linear drive track parallel to said pivotal axis, a rotary driving member rotatable about a predetermined axis, an actuating element supported on said driving member in radially offset relation to the axis thereof and coacting with said driving track to oscillate said drive lever between two extreme forward positions thereof corresponding to said respec tive pivot support legs, means on said housing defining two pumping chambers, two reciprocable pumping elements coacting with said respective chambers to pump fluid therethrough and being connected to said respective crossheads for reciprocation thereby, each of said drive lever pivot support legs defining a generally linear pivot support track, an adjustable pivot supported on each of said pivot support tracks, each of said crossheads defining on opposite sides of the intervening pivot support leg of the drive lever two transverse actuating tracks parallel to each other and coacting with said adjustable pivot on the support leg to translate arcuate movement of the pivot into linear movement of the crosshead, said actuating tracks on each crosshead and the pivot support track on the corresponding support leg being oriented in relation to each other to be mutually parallel when said drive lever is in its extreme forward position corresponding to the coacting support leg so that the location of the corresponding extreme forward position of the crosshead is the same for all positions of adjustment of the coacting adjustable pivot along said support track therefor, two threaded adjusting elements journalled in said drive lever for oscillation therewith and coacting with said respective adjustable pivots to adjust the latter individually along said support track therefor, two controls coacting with said respective threaded adjusting elements to rotate the latter adjustably, and visual indicating means coupled with each of said manual controls to indicate the effective stroke adjustment of the corresponding reciprocable pumping element.

4. An adjustable stroke pump comprising, in combination, a housing, a drive lever pivotally mounted in said housing for swinging movement about a pivotal axis, means on said drive lever defining a drive track therefor spaced from said pivotal axis thereof, a rotary driving member journalled in said housing for rotation about an axis that intersects the pivotal axis of said drive lever, a drive lever actuating slide journalled on said driving member in radially offset relation to the axis of the driving member for rotary movement with the driving member and rotation with respect thereto about an axis oriented to have a common intersection with both said axis of the driving member and said pivotal axis of the drive lever, said actuating slide engaging said drive track on said drive lever to oscillate said drive lever upon rotation of said driving member, a crosshead supported on said housing for reciprocable translation in a direction generally perpendicular to said pivotal axis of the drive lever, said crosshead defining a crosshead actuating track oriented in transverse relation to said direction of translation of the crosshead, said drive lever defining a pivot support track extending away from said pivotal axis of the drive lever, pivot means supported on said pivot support track for swinging movement therewith and adjustable displacement therealong, said pivot means engaging said crosshead actuating track to actuate said crosshead, said pivot support track having an orientation on said drive lever such that said trunnion support track is parallel to said actuating track on said crosshead when said drive lever is swung to its full forward position by said actuating slide on said driving member, means on said housing defining a pumping chamber, means for pumping fluid through said chamber including a reciprocable pumping element connected to said crosshead for actuation thereby, and adjusting means coacting with said pivot means to displace the latter adjustably along said pivot support track to adjust the stroke of said reciprocable pumping element incident to oscillation of said drive lever by said rotary driving member.

5. An adjustable stroke pump comprising, in combination, a housing, a drive pendulum pivotally mounted in said housing for swinging movement about a pivotal axis and extending downwardly therefrom, means on the lower portion of said pendulum defining a pendulum drive track, a rotary drive member journalled in said housing below said pendulum for rotation about an axis that intersects the pivotal axis of the pendulum, a pendulum actuating bearing journalled on said rotary drive member in radially offset relation to the axis of the drive member for rotary movement with the drive member and rotation with respect thereto about an axis oriented to have a common intersection with both said axis of the worm gear and said pivotal axis of the pendulum, said pendulum actuating bearing engaging said drive track on said pendulum to oscillate said pendulum upon rotation of said drive member, a crosshead embracing a medial portion of said pendulum, means supporting said crosshead for reciprocable translation in a direction transverse to said pivotal axis of the pendulum, said crosshead defining on opposite sides of said medial portion of the pendulum two crosshead actuating tracks oriented transversely in relation to said direction of translation of the crosshead, said pendulum defining a trunnion support track extending away from said pivotal axis of said pendulum, trunnion means supported on said trunnion support track for translation thereon and swinging movement therewith, said trunnion means including trunnions projecting in opposite directions, trunnion bearings supported on said trunnions and engaging said crosshead actuating tracks to actuate said crosshead, said trunnion support track having an orientation on said pendulum such that said trunnion support track is parallel to said actuating tracks on said crosshead when said pendulum is swung to its full forward position by said actuating element on said rotary drive member, means on said housing defining a pumping chamber, inlet and outlet valve means communicating with said chamber, pumping chamber expending and contracting means including a reciprocable pumping element connected to said crosshead for actuation thereby, and adjusting means coacting with said trunnion means to displace the latter adjustably along said trunnion support track to vary the stroke of said reciprocable pumping element incident to oscillation of said pendulum.

6. An adjustable stroke dual pump comprising, in combination, a housing, an oscillatory power lever pivotally mounted in said housing for swinging movement about a predetermined pivotal axis, said power lever including two pivot support legs traversing said pivotal axis and extending away therefrom in spaced generally parallel relation to each other, a pump stroke adjusting pivot movably supported on each of said pivot support legs for swinging movement therewith and adjustable displacement therealong a predetermined path between a position of coaxial alinement with said power lever pivotal axis and pumping positions radially displaced from said axis, pump stroke adjusting means coacting with each of said stroke adjusting pivots to progressively adjust the latter along said predetermined path on the support leg therefor, oscillating means coacting with said power lever to oscillate the latter through a predetermined range of angular movement, two crossheads corresponding to said respective pivot support legs of said power lever, crosshead support means supporting each of said crossheads for translation reversibly in a predetermined direction, each of said crossheads defining thereon an actuating track oriented transversely in relation to the direction of translation of the crosshead, said stroke adjusting pivot carried by each support leg coacting with the actuating track on the corresponding crosshead to reciprocate the crosshead as an incident to arcuate movement of the pivot produced by oscillation of the power lever, means on said housing defining two pumping chambers, and two reciprocable pumping elements coacting with said respective pumping chambers to pump fluid therethrough and being connected with said respective crossheads for operation thereby, said actuating track on'each crosshead being oriented thereon to have a parallel relation to said predetermined path along which the corresponding stroke adjusting pivot is adjusted in relation to its support leg on said power lever when said last mentioned support leg is swung to its extreme forward position by saidoscillating means so that the corresponding extreme forward position of the reciprocable pumping element connected with the crosshead is not changed by adjustment of the corresponding pivot along the coacting pivot support leg to change the stroke of the connected pumping element. v,

7. An adjustable stroke multiple pump comprising, in combination, a housing, three crosshead support :bars mounted in said housing in parallel spaced relation to each other, a drive lever pivotally mounted in said housing for swinging movement about a pivotal axis and including two generally parallel pivot support legs interleafed between successive support bars, two crossheads corresponding to said respective pivot support legs, each of said crossheads being slidably supported on the two adjacent support bars for reciprocable translation thereon, each crosshead being supported on each adjacent support bar by bearings spaced along the bar, each bearing defining a straight bearing surface slidably engaging the corresponding support bar, each bearing being supported rotatably on the corresponding crosshead to provide continuously for parallelism between the straight bearing surface on the bearing and the support bar engaged thereby, power drive means coacting with said drive lever to oscillate the latter between two extreme forward positions thereof corresponding to said respective pivot support legs, means on said housing defining two pumping chambers, two reciprocable pumping elements coacting with said respective chambers to pump fluid therethrough and being connected to said respective crossheads for reciprocation thereby, each of said drive lever pivot support legs defining an elongated pivot support track, an adjustable pivot supported on each of said pivot support tracks, each of said crossheads defining thereon a transverse actuating track coacting with said adjustable pivot on the corressponding support leg to translate arcuate movement of the pivot into linear movement of the crosshead, said actuating track on each crosshead and the pivot support track on the corresponding support leg being oriented in relation to each other to be mutually parallel when said drive lever is in its extreme forward position corresponding to the coacting support leg so that the location of the corresponding extreme forward position of the corresponding pumping element is the same for all positions of adjustment of the coacting adjustable pivot along said support track therefor, two threaded adjusting elements joumalled in said drive lever for oscillation therewith and coacting with said respective adjustable pivots to adjust the latter individually along said support track therefor, two controls coacting with said respective threaded adjusting elements to rotate the latter adjustably, and indicating means coupled with said controls to indicate the effective stroke adjustment of said reciprocable pumping elements.

8. An adjustable stroke multiple head pump comprising, in combination, a housing, three crosshead support bars mounted in said housing in parallel spaced relation to each other, a drive lever pivotally mounted in said housing for swinging movement about a pivotal axis and including two generally parallel pivot support legs interleafed between successive support. bars, two crossheads alined with said respective pivot support legs, each of said crossheads being slidably supported on the two adjacent support bars for reciprocation thereon, each crosshead being supported on each adjacent support bar by bearings individually defining a straight bearing surface slidably engaging the corresponding support bar and being rotatably supported on the crosshead in rotatable relation thereto to provide continuously for parallelism between the straight bearing surface on the bearing and the support bar engaged thereby, power actuating means coacting with said drive lever to oscillate the latter, means on said housing defining two pumping chambers, two reciprocable pumping elements coacting with said respective chambers to pump fluid therethrough and being connected to said respective crossheads for reciprocation thereby, each of said drive lever pivot support legs defining a pivot support track, an adjustable pivot supported on each of said pivot support tracks, each crosshead defining an actuating track coacting with said adjustable pivot on the corresponding support leg to translate arcuate movement of the pivot into crosshead movement, and adjusting means coacting with said respective adjustable pivots to adjust the latter individually along said support tracks therefor to adjust the strokes of said respective pumping elements.

9. An adjustable stroke pump comprising, in combination, a support, an oscillatory power lever pivotally mounted on said support for swinging movement about a predetermined pivotal axis, a pump stroke adjusting pivot movably supported on said power lever for swinging movement therewith and adjustable displacement therealong along a predetermined path extending away from said pivotal axis, pump stroke adjusting means coacting with said stroke adjusting pivot to progressively adjust the latter along said predetermined path on said power lever, oscillating means coacting with said power lever to oscillate the latter through a predetermined range of angular movement, a crosshead supported for translation reversibly in a predetermined direction, said crosshead defining thereon an actuating track oriented transversely in relation to the direction of translation of the crosshead, said stroke adjusting pivot carried by said power lever coacting with the actuating track on the crosshead to reciprocate the crosshead as an incident to arcuate movement of the pivot produced by oscillation of the power lever, means on said support defining a pumping chamber, and a recipro cable pumping element coacting with said pumping chamher to pump fluid therethrough and being connected with said crosshead for operation thereby; said actuating track on said crosshead being oriented thereon to have, when said support leg is swung to its extreme forward position by said oscillating means, a parallel relation to said predetermined path along which the corresponding stroke adjusting pivot is adjusted in relation to said power lever so that the corresponding extreme forward position of the reciprocable pumping element connected with the crosshead is not changed by adjustment of the corresponding pivot along said power lever to change the stroke of the connected pumping element.

10. An adjustable stroke dual pump comprising, in combination, a housing, an oscillatory power lever pivotally mounted in said housing for swinging movement along a predetermined pivotal axis, said power lever including two pivot support legs extending away from said pivotal axis in spaced generally parallel relation to each other, a pump stroke adjusting pivot movably supported on each of said pivot support legs for swinging movement therewith and adjustable displacement therealong along a predetermined path extending away from said power lever pivotal axis, pump stroke adjusting means coacting with each of said stroke adjusting pivots to progressively adjust the latter along said predetermined path on the support leg therefor, power oscillating means coacting with said power lever to oscillate the latter through a predetermined range of angular movement, two crossheads corresponding to said respective pivot support legs of said power lever, crosshead support means supporting each of said crossheads for translation reversibly in a predetermined direction, each of said crossheads defining thereon an actuating track oriented transversely in relation to the direction of translation of the crosshead, said stroke adjusting pivot carried by each support leg coacting with the actuating track on the corresponding crosshead to reciprocate the crosshead as an incident to arcuate movement of the pivot produced by oscillation of the power lever, means on said housing defining two pumping chambers, and two reciprocable pumping elements coacting with said respective pumping chambers to pump fluid therethrough and being connected with said respective crossheads for operation thereby, said actuating track on each crosshead being oriented thereon to have a parallel relation to said predetermined path along which the corresponding stroke adjusting pivot is adjusted in relation to its support leg on said power lever when said last mentioned support leg is swung to its extreme forward position by said oscillating means so that the corresponding extreme forward position of the reciprocable pumping element connected with the crosshead is not changed by adjustment of the corresponding pivot along the coacting pivot support leg to change the stroke of the connected pumping element.

11-. An adjustable stroke multiple pump comprising, in combination, support means, two generally straight crosshead support elements mounted on said support means and disposed in parallel spaced relation to each other, a drive lever pivotally mounted on said support means for swinging movement about a pivotal axis, a translatable crosshead disposed between said crosshead support elements and being slidably supported on each adjacent support element by bearings, each of said bearings defining a straight bearing surface slidably engaging the corresponding support element and being supported on the crosshead in rotatable relation thereto to provide continuously for parallelism between the straight bearing surface on the bearing and the support element engaged thereby, power actuating means coacting with said drive lever to oscillate the latter, means on said support means defining a pumping chamber, a reciprocable pumping element coacting with said chamber to pump fluid therethrough and being connected to said crosshead for reciprocation thereby, said drive lever defining a pivot support track extending away from said pivotal axis, an adjustable pivot supported on said pivot support track on said drive lever for oscillation therewith, said crosshead defining an actuating track coacting with said adjustable pivot on the drive lever to translate arcuate movement of the pivot into crosshead movement, and adjusting means coacting with said adjustable pivot to adjust the latter individually along said support track therefor to adjust the stroke of said pumping element.

12. An adjustable stroke pump comprising, in combination, a support, an oscillatory drive lever pivotally mounted on said support for swinging movement about a predetermined pivotal axis, means on said drive lever defining a drive track there-for spaced from said pivotal axis thereof, a rotary driving member journalled in said housing for rotation about an axis that intersects the pivotal axis of said drive lever, a drive lever actuating ele ment supported on said driving member in radially oflset relation to the axis of the driving member for rotary movement with the driving member and coacting with said drive track on said drive lever, said drive lever actuating element having a circular shape concentric with respect to an axis rotatable with said driving member and oriented to have a common intersection with both said axis of the driving member and said pivotal axis of the drive lever so that said actuating element rotates with respect to said drive lever and oscillates the drive lever upon rotation of said rotary driving member, a pump stroke adjusting pivot movably supported on said drive lever for swinging movement therewith and adjustable displacement therealong along a predetermined path extending away from said pivotal axis, a crosshead supported for translation reversibly in a predetermined direction, said crosshead defining thereon an actuating track oriented transversely in relation to the direction of translation of the crosshead, said stroke adjusting pivot carried by said drive lever and coacting with the actuating track on the crosshead to reciprocate the crosshead as an incident to arcuate movement of the pivot produced by oscillation of the drive lever, means on said support defining a pumping chamber, a reciprocable pumping element coacting with said pumping chamber to pump fluid therethrough and being connected with said crosshead for operation thereby, and pump stroke adjusting means coacting with said stroke adjusting pivot to progressively adjust the latter along said predetermined path on said drive lever to adjust the stroke of said pumping element incident to oscillation of said drive lever.

13. An adjustable stroke pump comprising, in combination, a housing sealed to contain lubricating fluid, a pumping unit mounted on said housing and defining a reservoir for fluid on the outboard side of the housing, said pumping unit defining a pumping chamber and including a reciprocable element coacting with said chamber to expand and contract the latter, inlet and outlet valves communicating with said chamber, a drive pendulum pivotally mounted in said housing for swinging movement about a pivotal axis and extending downwardly therefrom, means on the lower portion of said pendulum defining a generally linear pendulum drive track, a worm gear journalled in said housing below said pendulum for rotation about an axis that intersects the pivotal axis of the pendulum, a pendulum actuating slide journalled on said worm gear in radially ofiset relation to the axis of the worm gear for rotary movement with the worm gear and rotation with respect thereto about an axis oriented to have a common intersection with both said axis of the worm gear and said pivotal axis of the pendulum, a drive worm meshing with said worm gear to rotate the latter, said actuating slide engaging said drive track on said pendulum to oscillate said pendulum upon rotation of said worm gear, a crosshead embracing a medial portion of said pendulum, slide means on said housing supporting said crosshead for reciprocable translation in a direction generally perpendicular to said pivotal axis of the pendulum, said crosshead defining on opposite sides of said medial portion of the pendulum two crosshead actuating tracks generally perpendicular to said direction of translation of the crosshead, said pendulum defining a trunnion support track generally perpendicular to said pivotal axis of said pendulum, trunnion means supported on said trunnion support track for translation thereon and swinging movement therewith, said trunnion means including trunnions projecting in opposite directions, trunnion bearings supported on said trunnions and engaging said crosshead actuating tracks to actuate said crosshead, said trunnion support track having an orientation on said pendulum such that said trunnion support track is parallel to said actuating tracks on said crosshead when said pendulum is swung to its full forward position by said actuating slide on said worm wheel, an adjusting screw journalled in said pendulum in parallel relation to said trunnion support track and coacting with said trunnion means to move the latter adjustably along said trunnion support track, operating means coacting with said adjusting screw to rotate the latter, said trunnion support track on said pendulum being positioned on said pendulum to support said trunnion means in a Zero pump stroke position in which said trunnions are in coaxial alinement with said pivotal axis of said pendulum and to support said trunnion means and said trunnions on said pendulum for movement therealong toward or away from said zero pump stroke position upon rotation of said adjusting screw, said reciprocable element of said pumping unit being connected with said crosshead and extending between the crosshead and said pumping chamber through said reservoir, an impervious sealing diaphragm formed of a yieldable polymeric material and having an inner periphery and an outer periphery, said diaphragm having the overall form of a truncated cone and being corrugated between the inner and outer peripheries thereof to facilitate working displacement in an axial direction of said inner and outer peripheries relative to each other, said diaphragm being disposed in generally concentric relation to said reciprocable element; means forming a static, impervious sealed connection between said inner periphery of the diaphragm and said reciprocable element; and means forming a static, impervious sealed connection between the outer periphery of the diaphragm and said housing and said reservoir so that the diaphragm functions positively to preclude co-mingling of fluids in said housing and said reservoir and at the same time accommodates movement of said reciprocable element and said crosshead.

14. An adjustable stroke pump comprising, in com.- bination, a housing sealed to contain lubricating fluid, a pumping unit mounted on said housing and defining a reservoir for fluid on the outboard side of the housing, said pumping unit defining a pumping chamber and including a reciprocable element coacting with said chamber to expand and contract the latter, inlet and outlet valves communicating with said chamber, a drive lever pivotally mounted in said housing for swinging movement about a pivotal axis therefor, means on said drive lever defining a drive track, a worm gear journalled in said housing for rotation about a predetermined axis, an actuator rotatable with said worm gear in radially offset relation to the axis thereof, a drive worm meshing with said worm gear to rotate the latter, said actuator engaging said drive track on said drive lever to oscillate the latter upon rotation of said worm gear, a cross-head, means on said housing supporting said crosshead for reciprocable translation in a direction transverse to said pivotal axis of the drive lever, said crosshead defining a crosshead actuating track generally transverse to said direction of translation of the crosshead, said drive lever defining a trunnion support track extending away from said pivotal axis of said drive lever, trunnion means supported on said trunnion support track for translation thereon and swinging movement therewith, said trunnion means engaging said crosshead actuating track to actuate said crosshead, adjusting means coacting with said trunnion means to move the latter adjustably along said trunnion support track to adjust the stroke of said crosshead and said reciprocable element, said reciprocable element of said pumping unit being connected with said crosshead and extending between the crosshead and said pumping chamber through said reservoir, an impervious sealing diaphragm formed of a flexible material and having an inner periphery and an outer periphery, said diaphragm having the overall form of a truncated cone and being corrugated between the inner and outer peripheries thereof to facilitate working displacement in an axial direction of said inner and outer peripheries relative to each other, said diaphragm being disposed in generally concentric relation to said reciprocable element; means forming a static, impervious sealed connection between said inner periphery of the diaphragm and said reciprocable element; and means forming a static, impervious sealed connection between the outer periphery of the diaphragm and said housing and said reservoir so that the diaphragm functions positively to preclude co-mingling of fluids in said housing and said reservoir and at the same time accommodates movement of said reciprocable element and said crosshead.

15. An adjustable stroke pump comprising, in combination, a housing adapted to contain lubricating fluid, a pumping unit defining a pumping chamber and including a reciprocable element coacting with said chamber to expand and contract the latter, inlet and outlet valves communicating with said chamber, said pumping unit defining isolated reservoir space for fluid, a drive lever supported pivotally in said housing, actuating means in said housing coacting with said drive lever to oscillate the latter, a crosshead, means supporting said crosshead in said housing for reciprocable translation, said cross- 21 head defining a crosshead actuating track, said drive lever defining a trunnion support track thereon, trunnion means supported on said trunnion support track for translation thereon and swinging movement therewith, said trunnion means engaging said crosshead actuating track to actuate said crosshead, adjusting means coacting with said trunnion means to move the latter adjustably along said trunnion support track to adjust the stroke of said crosshead and said reciprocable element, said reciprocable element of said pumping unit being connected with said crosshead and extending between the crosshead and said pumping chamber through said reservoir space, an irnpervious sealing diaphragm formed of a flexible mate rial and having an inner periphery and an outer periphery movable axially in relation to each other, said diaphragm being disposed in generally concentric relation to said reciprocable element; means forming a static, impervious sealed connection between said inner periphery of the diaphragm and said reciprocable element; and means forming a static, impervious sealed connection between the outer periphery of the diaphragm and said housing 22 and said pumping unit so that the diaphragm functions positively to preclude co-rning1ing of fluids in said housing and said reservoir space and at the same time accom modates movement of said reciprocable element and said crosshead.

References Cited UNITED STATES PATENTS HENRY F. RADUAZO, Primary Examiner US. Cl. X.R.