US3382669A

US3382669A - Hydraulic booster apparatus

Info

Publication number: US3382669A
Application number: US552743A
Authority: US
Inventors: Alajos Z Bauer
Original assignee: Burndy Corp
Current assignee: FCI USA LLC
Priority date: 1966-05-25
Filing date: 1966-05-25
Publication date: 1968-05-14
Anticipated expiration: 1985-05-14
Also published as: BE698957A; CH463166A; NL6707161A; NL155479B; DE1625015B2; ES340803A1; DE1625015A1; SE325840B; GB1143142A

Description

May 14, 1968 A. z. BAUER 3,382,669

HYDRAULIC BOOSTER APPARATUS Filed May 25, 1966 2 Sheets-Sheet l E SM E May 14, 1968 A. z. BAUER 3,382,669 HYDRAULIC BOOSTER APPARATUS Filed May 25, 1966 2 Sheets-Sheet 2 /Qg U ik y .1"

11 PRESS u RE SEL ECTOR VALVE 1NVENT0R. ,9L/wos Z. Baus ATTORNEY United States Patent O 3,382,669 HYDRAULIC BOSTER APPARATUS Alajos Z. Bauer, Norwalk, Conn., assigner to Burndy Corporation, a corporation of New York Filed May 25, 1966, Ser. No. 552,743 4 Claims. (Cl. oil-10.5)

ABSTRACT F THE DISCLOSURE A hydraulic apparatus, for operating devices such as portable crimping tools, which is designed independently of a fluid pressure source and reservoir so that it may be attached conveniently to an external source and reservoir such as are found in common use on aerial lift trucks. The apparatus includes a hydraulic booster pump which is adapted to be driven by the fluid pressure derived from the external source, and control valve means together with a pressure reducing valve which will permit selective operation of the booster pump so as to supply either reduced pressure or boosted pressure to the utilization device.

This invention relates to a hydraulic booster aparatus, and more particularly to an apparatus which can be connected to an existing hydraulic system to generate and control sufficient pressure for operating various devices, such as an electrical connector crimping tool.

It is well known that hydraulic compression tools of the type used in securing electrical connectors to power lines commonly require pressure to be supplied at two different values on an alternate, selective basis. That is, a first pressure of 100 p.s.i. might be used to gently grip a connector between the jaws of the tool during an initial positioning operation, and a second pressure of 10,000 p.s.i. might be used for full compression force.

The reservoirs, pumps, compressors, and motive power sources for systems of this type are generally impractical to carry from one job to another. Further, their cost makes it desirable to avoid duplication wherever possible. Since compression tools of the type described are often used on or in the near vicinity of hydraulically operated aerial lift or boom trucks, it has been conceived that the hydraulic system normally carried by such trucks might be provided with a tap for supplying pressure to a hydraulic tool. However, the fluid pressure available from lift trucks may typically be on the order of 1500 p.s.i. which is just between the two alternate Values required for compression tool operation.

Accordingly, it is an object of this invention to provide a hydraulic system capable of operating on an input fluid supply pressure of an intermediate value so as to selectively produce output pressures which are substantially higher and substantially lower that the input, respectively.

It is a further object of the present invention to provide a hydraulic booster apparatus which can be directly connected to the existing hydraulic system of an aerial bucket truck.

Further objects of this invention are, to provide a system than can be adjusted to provide a range of different maximum pressures, that can be operated by hand on sight or by remote control, and that is relatively small in size and weight so as to make it easily portable.

These and other objects, features, and advantages of this invention will be illustrated and made more apparent by the system which is described in the following specification, particularly pointed out in the appended claims, and illustrated in the accompanying drawings, in which FIGURE 1 is a diagrammatic layout of a hydraulic ICC booster system assembled in accordance with this invention;

FIGURE 2 is a schematic representation of the control value of the system of FIGURE l, shown in the HOLD position; y

FIGUR-E 3 represents the control of FIGURE 2 in the OFF position;

FIGURE 4 is a schematic representation of the output and control valve portions of the system of FIGURE 1 showing modiiications thereof; and

FIGURE 5 is a pictorial representation of how a system of the type here disclosed might be carried on a commercial boom and bucket Referring now to FIGURE 1 of the drawings, the hydraulic booster system of this invention may be seen to comprise generally the operating elements 10 (enclosed within the dotted envelope) which are provided with a fluid input line 12, an output line 14, and a reservoir return line 16. The operating elements 10 include as basic equipment, a control valve 20 and a pumping unit 10; associated with the pumping unit are a shuttle valve 50, a pressure relief valve 60, a check valve 70, and a pressure reducing valve 80.

In practice, input line 12 would be connected to the high pressure hydraulic line (not shown) of an available hydraulic system in, for example, a hydraulically operated lift or boom truck. Reservoir return line 16 would in turn be connected to the fluid storage reservoir of such an available system in order to provide a complete flow path for the overall system of the invention. Commercially available iluid coupling devices of the quickdisconnect type might preferably be used for establishing these connections.

In use, output line 14 would be coupled to a hydraulic crimping tool or other such device for utilizing the uid pressure output of this invention.

Operation of the system illustrated in FIGURE 1 may be brielly described as follows: Overall operation is manually controlled by the position of control lever 21 on control valve 20. Three positions are provided, namely OFF, HOLD and CRIMP. In the OFF position shown in FIGURE 3, the ilow of liuid from input line 12 is completely cut off at valve 20, and the pressure in all other lines of the system is allowed to drain to the reservoir pressure in return line 16. In the HOLD position shown in FIGURE 2, lluid at 1500 psi. from line 12, is applied to pressure reducing valve 80. ri`his valve reduces the 1500 p.s.i. to a value of 100 psi, and transmits the reduced pressure iiuid through check valve into the output portion 42 of pumping unit 40 and then into output line 14. The CRIMP position of valve 20 shown in FIG- URE 1, applies 1500 p.s.i. pressure from line 12 through line 23 directly to shuttle valve 50'. This starts and operates the pump portion 45 of pumping unit 40. Operation of pump portion 46 raises or boosts the fluid pressure in output portion 42 of the pumping unit 40, from 100 p.s.i. to approximately 10,000 p.s.i. and forces this high pressure fluid into output line 14. Manipulation of valve 20 thus permits the pressure in output line 14 to be varied selectively from reservoir pressure to p.s.i. and to 1500 p.s.i.

A detailed explanation of fluid flow in this system during crimping operation may best be understood by reference to FIGURE 1. In the CRIMP position of valve 2t), input port P1 is internally coupled to both of output ports P2 and P3, and exhaust port P4 is effectively sealed. Fluid from line 12, at 1500 p.s.i. pressure, is thus applied to rcducingvalve 30, through line 22 which extends from port P2, and to shuttle valve 50, through line 23 which extends from port P3.

assassa Shuttle valve 50` is a two-way, two-position iluid valve which is provided with an inlet line 23, two

outlet lines

51 and 52, and an exhaust line 53. It operates in a wellknown manner to connect one outlet line to the inlet line and the other outlet line to the exhaust line, and to alternately reverse these connections in response to the position of shuttle arm d. The position of shuttle arm 54 is controlled by extension rod 47 which is coupled at one end to arm 54 and at the other end to pump plunger 49. Rod 47 and plunger 49' are in turn positioned by iluid forces acting on pump piston 48 which is mounted to rod 47. For example, with arm 54 in the position shown in FIGURE 1, iiuid from line 23 at 1500 p.s.i. pressure will be directed through outlet line 51 and be applied against the left side of piston 48, thereby forcing the piston toward the right, together with rod 47 and plunger 4?. Outlet line 52 at this time will be internally coupled, through shuttle valve 5d, to exhaust line 53, so that liuid on the right of piston 48 may return to the system reservoir through

lines

52, 53 and 16. As piston 48 reaches the extreme right end of its stroke, it will also have moved shuttle arm 54 to the right, thereby reversing the internal connections of lines 51 and 52 'within valve Si); In the new position of

valve

50, 1500 p.s.i. pressure will be applied to the right face of piston 43, forcing it toward the left. In this manner, piston 4S and plunger 49 will continue to reciprocate left and right, as long as uid pressure from line 12 is applied to line 23 through control valve 20.

The reciprocating operation described above drives plunger 49 alternately into and out of compression charnber 43 within output portion 4Z of pumping unit 46. Chamber 43 is kept continuously illed with hydraulic fluid supplied through check valve 70 and check valve feed line 72. As plunger d?! enters chamber 43, it tends to compress the fluid which is trapped within the chamber by the one-way dow characteristics of check -valve 70. When the pressure of the entrapped fluid becomes high enough, it acts to unseat valve head 44 against the load imposed by valve spring 4S, and permits the lluid to flow through passages 41 in valve head 44 into valve cylinder 38 and then into output line 14. The characteristics of plunger 49, chamber 43 and valve loading spring 45 may thus he chosen to produce a desired hydraulic pressure (such as 10,000 p.s.i.), in the uid which passes through valve cylinder 38 into output line 14.

FIGURE 2 illustrates duid low and internal connections for control valve 2d in the HGLD position. In this position, ports P4 and P3 are closed, and input port P1 is internally connected to port P2. With port 173 closed there is no iluid flow in line 23, so that shuttle valve 5d and pumping unit d@ will not operate. However, 1500 p.s.i. iluid from line 12 will be supplied to pressure reducing valve 30 through ports P1 and P2 and line 22. Accordingly, 100 p.s.i. luid will pass from the pressure reducing valve E50 to check valve 7d and then to compression char ber 43 in output portion 42 of pumping unit 4d. Valve head 44 will then unseat under the 100 p.s.i. pressure, and by-pass passages 41 in valve head t4 will permit the 100 p.s.i. duid in chamber 43 to dow into line 14.

In the OFF position of control valve 2d, schematically illustrated in FIGURE 3, input port P1 is closed to shut off iiuid flow through line 12, and ports P2 and P3 are internally connected to exhaust port P4. As may be seen more readily from FIGURE 1, the internal connections established by the OFF position of valve 2li permit the fluid in

lines

14, 22 and 23 to return to the reservoir pressure level of lines 16 and 16'. In the OFF condition of the system, pressure in output line 1li is drained olf to line 16 through operation of pressure relief valve 60. As shown in FIGURE 1, pressure relier valve 6@ include a spring loaded safety valve portion and a spring-andpiston operated drain valve portion 62. The input iluid sides of portions and 62 are cach coupled to valve cylinder 38 in pumping unit 4t) by a common passage 63. The output tluid sides of both of these portions are coupled by a common passage 64 directly to exhaust branch line 16. Safety valve portion 61 operates in conventional manner to exhaust fluid from passage 63 into exhaust branch 16 whenever the pressure in cylinder 38 exceeds a predetermined maximum value. Operation of drain valve portion 62 on the other hand, is controlled by duid pressure applied to valve piston 65. Drain valve portion 62 may be moved left or right to respectively open or obstruct connecting passage 67 which couples passage 63 to passage 64.-. A branch 2?.' of line 22 subjects the left face of drain valve piston 65 to the duid pressure which exists in line 22. When this system is in either CRIMP or HOLD position, the pressure in line 22 is sufficient to move piston 65 and valve portion `62 to the right so as to seal passage 6'7 against fluid ilow. In OFF condition, however, the tluid pressure in line 22 and branch line Z2 is essentially the same exhaust value as in exhaust lines 16 and 16', and accordingly there is no fluid pressure force acting on the left face of piston 65. Elimination of duid pressure on piston 65 permits the force of drain valve spring 66 to `move valve portion 62 toward the left, thereby opening connecting passage 67, and permitting high pressure uid in line 14 and chamber 38 to exhaust to the lower pressure of line 16' through

passages

63, 67 and 64. The pressure in output line 14 is thus reduced to its inital value so that another OFF-HOLD-CRIMP cycle of operation may be begun.

FIGURE 4 illustrates modications and additions which may be embodied into the system of FIGURE 1 within the scope of this invention. Elements shown in this ligure which have corresponding counterparts in FIGURE l are denoted by identical reference numerals increased by 160. Thus, for example, control valve 120 in FIGURE 4 corresponds generally to control valve 20 in FIGURE l. In the embodiment illustrated in FIGURE 4, the control lever on control valve 120 has been replaced by a pneumatic actuator 118. This actuator may comprise any well known form of pneumatically powered drive mechanism capable of producing at least intermittent arcuate motion to rotate the shaft of valve 120. A mechanism of this type could be activated 'by a hand-held squeeze-bulb such as 119 which might be coupled to actuator 118 by a liexible pneumatic tube 117 of convenient length. Such an actuator assembly would permit an operator to control a system of the type described accurately and conveniently, using non-conductive, non-electrical means, from a remote location.

-T he embodiment of FIGURE 4 further illustrates means for permitting the selection of either one of two different maximum output pressures in a system of the type disclosed. To do this, a pressure selector valve is posi- -tioned in the system interposed between pump output line 114 and nal output lines 114e and 1141). In use, the selector valve would be provided with input pressure from line 114 at a maximum value of, say 10,000 p.s.i. Depending on the position of selector lever 113i, the input pressure may be passed directly through to line 114a with no reduction in value, or may be internally routed through a reducing portion (not detailed) within valve 115, before passing to line 11427 at a reduced value of, for example, 6,000 psi. A connection to exhaust line branch 116 through sub branch 116 is provided to allow for any overflow or backup conditions within the valve. It can now be seen that a commercially available selector valve of this type, incorporated into the system of FIGURE l would substantially enhance the versatility and llexibility of such a system.

It can also be seen that such a system, incorporating available components, might be included within a case 9i) of reasonable size such as is shown in FIGURE 5. Such a case might be provided with one of more separabie hydraulic connectors 92 so that it could be conveniently carried into and mounted to a platform or bucket 94 on the aerial boom arm 9'1 of a lift truck (not shown).

'Ihis invention has now been described, but it should be understood that it is not confined to the particular forms or uses shown and described, the same being merely illustrative, and that the invention may be carried out in other ways without departing from the spirit of my invention, and therefore, the right is broadly claimed to employ all equivalent instrumentalities coming within the scope of the appended claims, and by means of which, objects o'f our invention are attained and new results accomplished, as it is obvious that the particular embodiments herein shown and described are only some of the many that can be employed to attain these objects and accomplish these results.

I claim:

1. A hydraulic booster apparatus for attachment to a separately existing hydraulic fluid system which has a pressurized hydraulic outlet port, said apparatus compn'sing:

first fluid conduit means, forming a hydraulic fluid passage which is attacha'ble at a second end thereof to a hydraulic fluid utilization device;

a hydraulic fluid pumping-unit forming part of said conduit means between the said first and second ends of said fluid passage;

said hydraulic fluid pumping-unit having an inlet directed toward the said first end of said fluid passage and an outlet directed toward the said second end of said fluid passage and being operable selectively to increase the pressure of fluid in said fluid passage from a given pressure at the inlet to a greater pressure at the outlet;

a fluid-driven motive power source operatively coupled to said pumping unit to permit selective operation of said pumping unit;

a fluid flow control valve interposed in said first conduit means between the said first end of said fluid passage and the said pumping-unit;

second fluid conduit means forming a hydraulicfluid passage between said fluid flow control valve and said fluid-driven motive power source for supplying fluid to drive said motive power source;

said control Valve being operable to selectively block and permit fluid through said first conduit means to the said second end thereof, and to simultaneously block and permit fluid flow through said second conduit means to said fluid-driven motive power source for causing selective operation of said pumping-unit;

whereby said apparatus may be made to deliver fluid from said separately existing hydraulic fluid system to said utilization device selectively, with or without increased pressure, in response to the operation of said fluid flow control valve.

2. -A hydraulic booster apparatus in accordance with claim 1, further including a pressure-reducing valve means interposed in said first conduit means between the said first end thereof and the said pumping unit, for reducing the pressure of the fluid obtained from said separately existing hydraulic system from an initial pressure to a lower pressure before said fluid is supplied to the said inlet of said pumping-unit.

3. A hydraulic booster apparatus in accordance with claim 2 wherein said separately existing hydraulic fluid system includes a fluid storage reservoir which is provided with an inlet port for receiving return fluid, and said booster apparatus further includes:

a one-Way check-valve interposed in said first conduit means between said pressure reducing valve means and said pumping unit, for limiting fluid flow to the direction from said reducing valve means to said pumping-unit only;

auxiliary conduit means coupled at a first end thereof to the inlet part of said separately existing hydraulic fluid system and coupled at a second end thereof to said first conduit means between said one-way checkvalve and the said second end of said first conduit means for returning fluid to said fluid storage reservoir;

and, pressure-operated relief-valve means interposed in said auxiliary conduit means between the said first and second ends of said auxiliary conduit means, for controlling the return of fluid from said pumping unit to the said fluid storage reservoir.

4. A hydraulic booster apparatus, for attachment to a separately existing hydraulic fluid system which has a pressurized hydraulic fluid outlet port and a fluid storage reservoir with an inlet port for receiving returned fluid, said apparatus comprising:

first fluid conduit means, forming a hydraulic fluid passage which is attachable at a first end thereof to the pressurized hydraulic fluid outlet port of a hydraulic fluid system and is attachable at a second end thereof to a hydraulic fluid utilization device;

a hydraulic fluid pumping-unit forming part of said conduit means between the said rst and second ends of said fluid passage;

said hydraulic fluid pumping-unit having an inlet directed toward the said first end of said fluid passage and an outlet directed toward the said second end of said fluid passage and 'being operable selectively to increase the pressure of fluid in said fluid passage from a given pressure at the inlet to a greater pressure at the outlet;

a fluid-driven reciprocating motive power source including a shuttle Valve means, operatively coupled to said pumping-unit to permit selective operation of said pumping-unit and adapted to be driven by hydraulic fluid pressure obtained from said hydraulic fluid system through said first conduit means;

a fluid-flow control Valve, having first, second and third operating positions, interposed in said first conduit means between the said first end of said fluid passage and the said pumping-uit;

an inlet on said fluid flow control valve forming part of said first conduit means;

a first outlet on said fluid flow control Valve, forming part of said first conduit means;

a second outlet on said fluid flow control valve operatively coupled to said reciprocating motive power source for supplying operating fluid pressure thereto;

pressure-reducing valve means interposed in said first conduit means between the said rst end thereof and the said pumping-unit, for reducing the pressure of the fluid obtained from said separately existing hydraulic system from an initial pressure to a lower pressure before said fluid is supplied to the said inlet of said pumping-unit;

a one-way check-valve interposed in said first conduit means lbetween said control valve means and said pumpingeunit for limiting uid flow to the direction from said control valve means towards said pumpingunit only;

auxiliary conduit means having a first end thereof coupled to the inletport of said separately existing hydraulic fluid system and a second end thereof coupled to said first conduit means fbetween said one-way check-valve and the said second end of said first conduit means for returning fluid to the said fluid storage reservoir;

a pressure operated relief valve means interposed in said auxiliary conduit means between the said first and second ends of said auxiliary conduit means for selectively controlling the return of fluid from said first conduit means to the said fluid storage reservoir;

fluid passage means operatively coupling said pressure-operated relief valve means to said first conduit means intermediate said fluid flow control valve means and said one-way check-valve for supplying uid pressure to operate said relief valve in response to the position of said fluid ow control valve means;

a third outlet on said fluid ow control valve means operatively coupled to said inlet of said lluid storage reservoir for returning hydraulic fluid from said control valve means to said fluid storage reservoir in response to the position of said fluid low control valve means;

the said first position of said lluid low control valve means `being adapted to -block iluid flow from the rst end of said first conduit means and to provide fluid flow passage means coupling said irst and second outlets to said third outlet for returning uid from said apparatus to said fluid storage reservoir;

the said second position of said fluid flow control valve means being adapted to block fluid ow from said second and third outlets and to provide fluid tlow passage means coupling said inlet to said outlet for permitting iluid ow from said rst end to said second end of said conduit means; and

the said third position of said uid flow control valve means being adapted to block fluid ow through said third outlet and to provide uid ow passage means coupling said inlet to said rst and second outlets for permitting fluid llow through said first conduit means and for supplying fluid pressure to operate said reciprocating motive power source.

References Cited UNITED STATES PATENTS 886,379 5/1908 Laursen 103-50 1,332,340 3/1920 Horne 60-51 1,888,990 ll/ 1932 Kurath 60-54.5 2,080,695 5/1937 Garg-ile 103-50 2,608,059 8/1952 Kux 60-54.5 2,867,088 1/1959 Kux 60-545 3,041,975 7/ 1962 Atherton et al 103-50 3,186,173 6/1965 Hogg 60-54.5

FOREIGN PATENTS 768,258 2/ 1957 Great Britain.

20 MARTIN P. SCHWADRON, Primm Examiner.

R. R. BUNEVICH, Assistant Examiner.