Патент USA US2083854код для вставки
June V15, 1937. R. E.- McGEE ‘ . 2,083,854 HYDRAULIOPUMP 3 Filed Sept. 12, 1935 ‘s7wig. 48 INVENTOR. ?oat/er 5 M5 6:: \ ATTORNEY. ‘ Patented June 15, 1937 - ‘2,083,854 UNITED STATES PATENT OFFICE‘ 2,083,854 HYDRAULIC PUMJP Robert E. McGee, Beeville, Tex. Application September 12, 1935, Serial No. 40,208 4 Claims. This invention relates to new and useful im provements in hydraulic pumps. One object of the invention is to provide an im proved hydraulic pump which may be utilized to (Cl. 103-37) from a reading of the'iollowing speci?cation and by reference to the accompanying drawing, in which an example of the invention is shown, and. wherein: _ - Figure 1 is an elevation of a hydraulic pump, 5 actuate a ram, jack, or other mechanism. An important object of the invention is to pro vide an improved hydraulic pump which is so con structed that upon initial actuation the pump will constructed in accordance with the invention. Figure 2 is a transverse, vertical sectional view taken on the line 2-2 of Figure 1, and showing act as a large displacement low pressure pump, both pistons in a lowered position, . Figure 3 is a plan view, ' 10 further actuation of said pump converting the same into a small displacement high pressure pump, whereby when the load is light a large amount of ?uid is displaced at a low pressure and when said load increases a small amount of ?uid 15 is. displaced under a high pressure. Anotherobject of the invention is to provide an improved hydraulic pump which includes a . double piston, one larger than the'other, the pis tons. being so arranged that upon initialractua 20 tion of the pump the large piston is moved to dis place a greater amount of ?uid under a low pres sure, continued actuation of the pump causing the smaller piston to come into action to displace less ?uid under a high pressure, whereby the pump is 25 automatically converted from a low pressure to a high pressure pump as the load increases and the high pressure'is necessary. ' 5 10 Figure 4 is a view similar to Figure 3, and show ing the large piston locked in its lowered position, Figure 5 is an elevation of the upper portion of the pump taken at right angles to Figure 1, and , 15 Figure 6 is a transverse, vertical sectional view taken on the line 6—6 of Figure 3. _ In the drawing the numeral l0 designates a cylinder which is shown disposed vertically, and _ this cylinder has its bottom closed while its upper 20 end is opened. The cylinder may be made of metal, or any other suitable material and its par ticular size is subject to variation. The upper end of the bore of the cylinder’ is formed with an internal, annular shoulder H on which a suitable 25 packing ring l2 rests. The packing ring is held in position by a suitable packing gland l3 which A further object of the inventionis to provide is threaded into the upper end of said cylinder, an improved hydraulic pump including a large ' as is clearly shown in Figure 6. The packing gland has an annular peripheral ?ange at its 30 30 piston and a small piston with means for connect upper end and the upper end of the cylinder is ing the two pistons so that they will move simul taneously, so that upon initial actuation of the counter sunk at M whereby when the gland is screwed downwardly into position the upper end pump a large amount of ?uid under a compara tively low pressure will be displaced, and means thereof will be ?ush with the top of the cylinder. An enlarged piston I5 is mounted to slide with- 35 35 for disconnecting the pistons from each other after the large piston has completed its full in the cylinder l0 and the piston has a length sub stroke, whereby the small piston may then be stantially the length of said cylinder. The upper actuated independently of the large piston to end of said piston is provided with an outwardly directed peripheral ?ange l6, and this ?ange is displace ?uid under a high pressure. 40 A still further object of the invention is to arranged to engage the upper end of the cylin- 4o provide an improved hydraulic pump including a der when said piston is in its lowermost position large piston slidable within a cylinder and a small (Figure 2) . The piston is provided with an axial piston slidable within. the large piston with means bore ll which extends throughout the length 'for connecting the two pistons together so that thereof and the upper end of the bore is formed 45 they will move as a unit, and means actuated by the fluid pressure for disconnecting the two pis tons when the ?uid pressure has equalled the with an annular shoulder or recess l8 whereby 45 a suitable packing ring l9 and packing gland 69’ may be located therein. An inner or reduced pis pressure being exerted thereagainst by the large ton 20 is mounted to slide within the axial bore piston whereby after such equalization the small ll of the large piston I5 and this inner piston is 50 piston may be independently operated to increase provided with an enlarged head 20' near its upper 50 the pressure of the ?uid. end. When the piston 20 is in its lowermost position A construction designed to carry out the in vention will be hereinafter described, together within the axial bore ll (Figure 2), the head 20' with other featuresof the invention. 55 The invention will be more readily understood thereof is located within an upwardly extending collar 2! which is made integral with the enlarged 55 I .2 2,083,854 piston I5. The piston I5 is provided with a suit able packing cup I5’, while the smaller piston 20 the outlet line 26 will be under a comparatively low pressure. However, at this time a compara has a similar packing cup :2 at its lower end. It ' tively large amount of ?uid will be displaced be cause of the large size of the piston I5. There will be seen by observing Figure 2 that the en UK larged piston I5 is arranged to slide within the cylinder I0. Leakage of ?uid is prevented by the packing cup I5’ and the packing ring I2 at the upper end of the cylinder. Leakage through the bore IT of the large piston is prevented by the 10 packing cup 22 on the inner piston 20 and also by the packing ring I8 at the upper end of said bore. The bottom I0’ of the cylinder is provided with a port 23 which extends diametrically through said bottom. One end of‘the port has an inlet pipe 24 connected therewith whereby hydraulic ?uid is introduced into said port‘. A suitable check valve 25 is connected in the inlet line 24. The other end of the port has an outlet pipe 26 20 connected therewith which also has a check valve 21 mounted therein. The port communicates with the interior of the cylinder Ill through an axial opening 28 which is formed in the bottom Ill’. Thus it will be seen that hydraulic ?uid 25 entering the port through the inlet pipe 24 may ?ow into the interior of the cylinder I0 when the pistons I5 and 20 are in their raised position. It will be obvious that when the pistons move down- - wardly within the cylinder the hydraulic ?uid 30 will be forwarded outwardly through the port 23 into the outlet line 26 and to the check valve 21 and then to a ram, jack, or other mechanism. For reciprocating the pistons I5 and 20 within the cylinder, the head 20’ of the inner piston 20 is provided with an upwardly extending arm 29. This arm has a lever 30 pivoted thereto, as is nected together and the lever 30 is swung it will be seen that a low pressure large displace ment pump will be had. Therefore when the ram is ?rst actuated, at which time the load is light, a comparatively large amount of hydraulic ?uid 10 under a low pressure is forced thereagainst. This is desirable because upon initial movement of the ram when the load is light a high pressure ?uid is not necessary and by providing a com paratively large amount of fluid under a low 15 pressure the initial movement of the ram is in creased. When the back pressure on the ?uid Within the line 25 increases due to an increased load on the ram which it is operating, a point will be reached when this back pressure is equal to 20 the pressure which can be exerted downwardly by the enlarged piston I5. When this occurs fur ther actuation of the enlarged piston I5 will be stopped and therefore it is necessary to apply more pressure to the ?uid. At such time ‘it is desirable to disconnect the piston I5 from the smaller piston 20 and permit the smaller piston to operate independently of the large piston. Due to the small cross-sectional area of the inner pis ton 20 it will be seen that a much higher pres 30 sure may be_applied to vthe ?uid through the reciprocation of this smaller piston. For auto matically disconnecting the two pistons from each other when the equalization of pressure, above referred to, occurs, the ?ange I6 of the large pis ton I5 is formed with a pair of diametrically cleary shown in Figure 1. The pivot of the lever opposite notches or cut out portions 35 (Figures is nearer one end of said lever and that end of 3 and 4). Normally, ‘these notches are in align ment with upwardly extending arms 36 which are formed integral with the cylinder I0. By ob elf) serving Figure 3, it will be seen that with the notches in alignment with said arms, that the piston I5 is free'to move vertically. The lower end of the arms 36 are provided with inwardly the lever is pivoted to an upwardly extending 40 bracket arm 3'I which is preferably made integral with, and extends upwardly from the cylinder I0. It will be seen that when the lever 30 is swung on vits pivot the inner piston will be raised and lowered. , For connecting the piston 20 with the larger piston I5. whereby swinging of the lever 30 will operate both pistons simultaneously, the head 20’ of the inner piston 20 is provided with a pair of diametrically opposite, outwardly extending pins 32.‘ These pins are arranged to engage in L-slots 33 which are formed in the collar 2| which ex tends upwardly from the enlarged piston I5 (Fig ures 2 and 5). It will be 'seenthat when the pins 32 are engaging in the horizontal leg of the slots 33 that the pistons I5 and 20 are connected together, whereby a vertical movement of the inner piston 20 will move the large piston I5 ver tically within the cylinder I0. Therefore, so long as said pins are in vengagement with the slots directed slots 0r notches 31 which are of a width substantially equal to the width of the ?ange I6. Therefore, when the piston I5 is rotated in a clockwise‘ direction (Figure 3) the cut out por tions 35 of the ?ange It will be moved out of alignment with the vertically extending arms 36 and the ?ange I6 will move into the notches 31 on‘ the inner face of said arm. When the ?ange engages in\these notches (Figure 2) it will be seen that further vertical movement of the pis ton I5 will be prevented. It is noted that the ‘notches 31 are so located that the piston I5 must is applied to the hydraulic ?uid beneath the pis ton by the enlarged piston I5. It is noted that be in its lowermost position before the ?ange I6 can engage said notches. Therefore, the notches 31 and ?ange I6 provide means for locking the large piston I5 in its lowermost position. It is further pointed out that when the piston I5 is rotated to engage the ?ange I6 in the notches when the pistons are so connected the inner pis ' 31, such rotation causes the collar 2I at the upper ton becomes an integral part of the large piston and does not act independently thereof. end of said piston to be rotated therewith. Rota tion of this collar (Figure 5) in a clockwise direc tion causes the horizontal leg of the L-shaped slots 33 to move away from the pin 32 whereby said GO the pistons operate _ a single unit and pressure ' Assuming for purposes of description, that the outlet line 26 has its opposite end connected to a . mm (not shown) it will be obvious that when the . "lever 30 of the device is swung with the pistons I5 . and 20 connected together through the medium pfgthe pins 32, that the hydraulic fluid beneath 'i- he-pistons will be forced outwardly to the ram the enlarged piston I5. Due to the large cross -_ fore so long as the pistons I5 and 20 are con sectionalarea of said piston, it will be seen that 15: the ?uid which is forcedfrom the cylinder through pin is aligned with the vertical leg of the slot. Thus it will be seen that rotation of the piston I5 not only looks said piston in its lowermost posi tion, but also causes the pin 32 to be disengaged from the slots 33 whereby the inner or smaller piston 20 is free to move vertically within the axial bore I’! of the piston I5. ' For automatically accomplishing the rotation 2,088,854 . of the large piston l5 to disconnect the inner pis ton 20 therefrom and also to lock said large pis ton in its lowermost position, a check valve 40 is provided. The valve 40 is connected in a by pass line 4| which has one end connected with the interior of the cylinder In above the bottom thereof.- The other end of the line 4| is con nected to the met line 24 at a point in front of the check valve 40. The valve stem 42 of 1 0 said valve extends upwardly from the upper end of the valve and a coil spring 43 normally holds said valve close-d. The upper end of ‘the stem) 42 has the lower end of an actuating rod 44 con/ nected therewith. The rod 44 is arranged to slide within a groove 45 which is formed in the outer surface of the cylinder Ill. The upper end of said rod extends through a groove 45’ formed on the inner periphery of a metal ring 45 which is slidably mounted on the upper end of the cyl inder Ill. The extreme upper end of the rod 44 has an outwardly directed lug 41 which over hangs the upper end of the ring 46. This lug is adapted to ?t in a recess or notch 38 which is formed in the upper end of the ring 46. ‘It will be obvious by observing Figures 1 and 2 that when the valve 40 is in a closed position the lug _ 3 through the medium of the pins 32 and slots 33. Also, the cut out portions 35 of the ?ange I6 of the large piston are in alignment with the vertical arms 36 which extend upwardly from the cylinder Ill. When the hand lever 30 is de pressed it will be obvious that the two pistons will move as a unit. Therefore, as the large pis ton l5, and the small piston connected there with, move, vertically within the cylinder l0‘ it will' be obvious that a comparatively large 10 amount of ?uid will be displaced into the outlet pipe 26 under a comparatively lovtr pressure. As pointed out above, this low pressure is due to the fact that the cross-sectional area of the pis ton I5 is comparatively large. A suitable cushion 15 52 (Figure 2) may, if desired, be located in the lower end of the cylinder l0 to cushion the stroke of the large piston. This cushion will, of course, be provided with an axial opening 52' through which the smaller piston, when independently 20 operated, may pass. Continued reciprocation of the two pistons as a unit will, of course, build up the pressure in the outlet lines 26 and when this pressure builds up to a point where it is equal to» the force ex erted downwardly by the piston l5 then this 41 is in engagement with the recess 38~whereby pressure will be suf?cient to overcome the pres the ring 45 is held in a stationary position with . sure of the spring 43 on the valve stem 42 which is holding the valve 40 closed. Therefore, when relation to the cylinder ID. the equalization ‘of pressure occurs, the valve 40 The ring 46 has one end of a coil spring 48 secured thereto. This coil spring is wound will be raised to permit the ?uid within the lower. around the cylinder l0 and has its other end end of the cylinder and under the pressure which secured to said cylinder. It'is pointed out that the large piston |5 has built up, to escape through when the spring is ?rst located it is placed under the line 4| and back into the inlet line 24. When the valve stem 42 is lifted due to the opening of a tension whereby it tends to rotate the ring 48 the valve 46, the rod 44 which is located in the in a clockwise direction. So long as the lug 4'! vertical groove 45 in the side of the cylinder It] of the rod 44 is in engagement with the recess will, of course, be raised. The raising or lifting or notch 45' in the upper side of the ring 46, it will be obvious that said ring is held in its» of the rod 44 will disengage the lug 31 at its 4 0 fixed position and is not capable of a rotation. upper end from the recess or ‘notch 48 in the 40 However, when the rod 44_is raised to disengage ring 46 which surrounds the cylinder l0. the lug 47 from the recess 45' it will be obvious soon as the lug 4‘! is disengaged from said notch, that the spring 48 will immediate-1y rotate the ring 46 in a clockwise direction. For communi the coil spring 49 will immediately rotate the cating this‘ rotatable movement of the ring 46 to the large piston l5, the ring is provided with‘ an upwardly extending rod 50. This rod is so positioned that when the ring is held in its sta tionary position by the engagement of the lug ‘41 in the notch .45’, said rod 50' is rotated con tiguous to a radially extending handle 5| which is made integral with the ?ange |6 of the pis ton .|5. By observing Figure 3, it will be see-n that when the lug 41 is disengaged from the not-ch 45' due to.the lifting of the rod 44, the ring 46 will be rotated by the coil spring 48. R0 tation 'of the ring 46 will,»of course, move ,the upwardly extending arm 50 around the outer pe riphery of the cylinderv In. The movement of 60 As ring 46. Rotation of the ring 46 will cause the rod 50 which is secured thereto to engage the radially extended handle 5| on the ?ange l5 of the piston l5, whereby “the piston |5 is rotated in'a clockwise direction. As explained above, this'rotation will cause the ?ange N5 of the pis ton to engage the notches 31 in the vertical arm 36 to lock the piston in its lowermost position. At the same time the pins 32 are disengaged from the horizontal leg of the slots 33 which disen gages the inner piston 20 from the outer piston I5, thereby permitting said inner piston to be operated independently'of the large piston. I Thus it will be seen that when the pressure built up by the operation of the piston l5 equals the force which is exerted by said piston, then the piston is locked in a lowermost position and this rod causes said rod to engage the radially extended handle 5| on the piston l5, whereby‘ the smaller piston 20. is disconnected from the said piston is rotated in a clockwise direction. large piston to permit independent operation of As has been explained the clockwise rotation of the piston l5 will cause the ?ange I6 to engage Li the notches 31 in the arm 36 to lock the large piston I5 in its lowermost position. At the same time this rotation of the piston l5 causes the said smaller piston. Due to the small cross sectional area of the piston 20 operating within the axial bore I‘! of the large piston, it will be 65 obvious that continued actuation or swinging of ‘ the hand lever 30 will reciprocate the smaller piston 20 to displace a smaller amount of ?uid pins 32 on the inner or smaller piston 20 to dis engage the horizontal leg of the L-slot 33, Whereby the inner or smaller piston 20 is free to un dergo a vertical movement within the axial bore from the lower end of the cylinder under a higher pressure. Therefore it will be seen that l’! of the large piston l5. tively large amount of fluid under a lower pres sure is displaced into theoutlet lines 26 and to _ In operation, the'parts are moved to the posi tion shown in Figure 1, with the inner or smaller piston 20 connected with the large piston |5 60 upon initial actuation of the pump a compara the particular mechanism which the ?uid is ac tuating. After the large piston l5 has built up 4 2,083,854 the maximum pressure of which it is capable, then the smaller piston 20 is automatically dis by that piston after which time the second pis connected from, the larger piston and is oper ated independently to displace a less amount of ?uid under a higher pressure to the particular mechanism. Therefore in utilizing the pump to. pistons against such spring urged rotation and ton is actuated, a spring element for urging said pistons rotatably in one direction, pressure con trolled latch means for releasably holding said a single means for moving the pistons. 2. A hydraulic pump including, a cylinder hav ing ?uid therein, a piston slidable in said cyl inder and having an axial opening therethrough, a second piston slidable within the opening of 10 displace a comparatively large amount of ?uid the ?rst piston, means for connecting the piston whereby both pistons move simultaneously and so as to bring about an increased movement of the ram to bring it into actual working position. act as a large piston until such time as su?icient Since the load on the ram is light at the start ‘ pressure of the ?uid has been built up to equal 15 of the movement, the ?uid which is actuating the force exerted by said large piston, means for 15 said ram at this time need not be under a high disconnecting the pistons whereby the second actuate a ram, it will be seen that upon initial actuation or at the start of the movement of the ram, there is practically no load or a very light 10 sad on said ram. In such case it is desirable to pressure. Therefore the large piston l5 moving upon initial actuation of the pump will displace this large amount‘ of ?uid under a low pressure 20 to begin the movement of the ram and to, rap idly bring it- into .its operating position. After the load increases on the ram and there is a ne amount of ?uid. under a high pressure, means cessity for high pressure then the smaller piston for locking the ?rst piston in its lowermost po is brought into-play and through the‘ actuation sition when the second piston is disconnected therefrom, and means actuated by the pressure 25 of the ?uid for simultaneously operating the dis connecting means and the locking means. 3. A hydraulic pump including, a cylinder hav 25 or reciprocation of said smaller piston the ?uid is forced to'the ram under a comparatively high pressure. Although the smaller piston is capa ble of placing a higher pressure on the ?uid, it is pointed out that due to its small cross-sec 30 tional area it cannot displace as large amount of ?uid as the larger piston l5. 'However, the displacement of a large amount of ?uid at this time ‘is unnecessary because the ram is already in its working position and a load is imposed 35 thereon which requires a high pressure on the ing ?uid therein, a piston slidable in said cyl inder and having an axial opening therethrough, 80 a second piston slidable within the opening of the ?rst piston, means for connecting the pis tons whereby both pistons move simultaneously and act as a single large piston until such time as the ?uid pressure built up by said piston 35 ?uid. The release of the large piston, after it has equals the force exerted by thepiston, and means actuated by the ?uid pressure for disconnecting beenlocked in its lowermost position and its con the piston and locking the ?rst piston in an in active position, whereby the second piston may then be operated independently to displace a nection to the smaller piston 20 after having 40 been disconnected, is easily accomplished by merely grasping the handle 5! on the ?ange N5 of the large piston 15 and rotating said piston in a counter-clockwise direction. This returns ' the parts to their normal position, the lug 41 45 dropping into the recess 45' to again lock the ring 46 in its ?xed position and the pump is ready for the next operation. What I claim and desire to secure by Letters Patent is: 50 piston may be operated independently of the ?rst piston after such equalization occurs, there by ?rst displacing a comparatively large amount of ?uid from the cylinder under a low pressure 20 and then displacing a comparatively small ~ ~ 1. A hydraulic pump including, a cylinder hav comparatively small amount of ?uid under a high pressure. 4. A hydraulic pump including, a cylinder hav ing ?uid therein, a piston slidable in said cylin der and having an axial opening therethrough, a second piston slidable within the opening of the ?rst piston, means for connecting the pis ‘tons whereby both pistons move simultaneously and act as at single large piston until such time as the ?uid pressure built up by said piston‘ 50 ing ?uid therein, a piston slidable within said 'equals the force exerted/by the piston, means - cylinder for displacing the ?uid therefrom un ~Hder a low pressure, a second piston smaller than the ?rst piston for displacing the ?uid from the 55 cylinder under a high pressure, said pistons be ing rotatable in said cylinder means for connect-. ing the'pistons whereby they move as a single unit until the pressure built up by the movement of the ?rst piston is equal to the force exerted actuated by the ?uidk‘pressure for disconnecting the piston and locking the ?rst piston in an in active position, whereby.‘ the second piston may then be operated independently’ to displace a 55 comparatively small amount of ?uid under a‘ high pressure, and a single means for moving the ' pistons. ROBERT E. MCGEE. '