US3786723A - Hydraulic oscillator - Google Patents
Hydraulic oscillator Download PDFInfo
- Publication number
- US3786723A US3786723A US00253514A US3786723DA US3786723A US 3786723 A US3786723 A US 3786723A US 00253514 A US00253514 A US 00253514A US 3786723D A US3786723D A US 3786723DA US 3786723 A US3786723 A US 3786723A
- Authority
- US
- United States
- Prior art keywords
- passage
- booster
- valve
- working space
- flow
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 230000009471 action Effects 0.000 claims abstract description 11
- 238000005086 pumping Methods 0.000 claims description 23
- 238000004891 communication Methods 0.000 claims description 22
- 239000012530 fluid Substances 0.000 claims description 19
- 238000012546 transfer Methods 0.000 claims description 10
- 230000002093 peripheral effect Effects 0.000 claims description 7
- 238000011161 development Methods 0.000 abstract description 4
- 230000000284 resting effect Effects 0.000 abstract description 2
- 230000000694 effects Effects 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 238000013459 approach Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 230000035939 shock Effects 0.000 description 2
- 238000013022 venting Methods 0.000 description 2
- 239000004677 Nylon Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 230000008520 organization Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B06—GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS IN GENERAL
- B06B—METHODS OR APPARATUS FOR GENERATING OR TRANSMITTING MECHANICAL VIBRATIONS OF INFRASONIC, SONIC, OR ULTRASONIC FREQUENCY, e.g. FOR PERFORMING MECHANICAL WORK IN GENERAL
- B06B1/00—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency
- B06B1/18—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency wherein the vibrator is actuated by pressure fluid
- B06B1/183—Methods or apparatus for generating mechanical vibrations of infrasonic, sonic, or ultrasonic frequency wherein the vibrator is actuated by pressure fluid operating with reciprocating masses
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
- F03C1/00—Reciprocating-piston liquid engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03C—POSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
- F03C1/00—Reciprocating-piston liquid engines
- F03C1/08—Distributing valve-gear peculiar thereto
- F03C1/14—Distributing valve-gear peculiar thereto by driving liquid of engine
Definitions
- the primary object of this invention is to provide an improved oscillator of the kind mentioned which is relatively inexpensive to manufacture, and in which the distributing valve is operated exclusively by hydraulic pressures and is self-starting under all conditions.
- the new oscillator employs a unified, four-way distributing valve which is urged toward one of its two operative positions by a spring or other suitable biasing device, and is shifted by a pair of fluid pressure motors which act on the valve in opposition to each other and have unequal effective areas.
- the smaller actuating motor which acts on the valve in the same sense as the biasing device, normally is connected with one working space of the power element through a booster pumping device, but receives fluid at the amplified output pressure of that device during the terminal movement of the power element in one direction.
- the larger actuating motor normally communicates with the other working space of the power element, but is furnished with fluid at the amplified output pressure of a second booster device during terminal movement of the power element in the opposite direction.
- the two actuating motors are interconnected through a restricted passage.
- the distributing valve also performs a flow-dividing function and diverts to a reservoir or tank a controlled portion of the fluid supplied to the oscillator.
- This feature precludes full cut-off of the supply flow at the ends of the strokes of the power element, and thereby minimizes pressure peaks or shocks in the supply system.
- the flowsplitting action of the distributing valve can be adjusted. Inclusion of this feature allows oscillator frequency to be selected independently of the rate of supply, and thereby makes possible the use of a single oscillator design in various applications even though the rates of supply are quite different.
- Another feature of the preferred oscillator consists in making adjustable the restriction in the cross-connection between the actuating motors. This expedient is useful to prevent development of excessive pressures in the booster output circuits and to permit control over the rate at which the boosters decelerate the power element.
- FIG. 1 is a schematic diagram of the basic oscillator.
- FIG. 2 is a sectional view of the preferred oscillator.
- FIG. 3 is a sectional view taken on line 3-3 of FIG. 2.
- FIG. 4 is a sectional view of an alternative distributing valve for the embodiment of FIG. 2.
- Pumping unit 29 comprises a booster cylinder 32 which is aligned with cylinder 12 and opens into working space 14, and a cooperating pumping member comprising a booster piston 33 which is fixed to power piston 13 and fits cylinder 12 with a radial clearance on the order to 0.001 to 0.002 inches.
- booster cylinder 32 is in free communication with working space 14, so actuating motor 23 is subjected to substantially the same pressure as that prevailing in the working space.
- piston 33 enters booster cylinder 32 and isolates it from free communication with space 14.
- booster piston 33 serves as both a restricting element and a pumping element.
- Pumping unit 31 is identical to unit 29 and includes a booster cylinder 35 and a cooperating pumping member comprising a booster piston 35.
- the pumping unit 31 is associated with working space 15 and is effective to pressurize actuating motor 24 during the terminal portion of the rightward movement of power piston 13.
- the units 29 and 31 cooperate with restricted passage 25 to define hydraulic'snubbers for for power piston 13 which bring the latter to a cushioned stop in both directions of movement.
- hydraulic'snubbers for for power piston 13 which bring the latter to a cushioned stop in both directions of movement.
- each booster piston 33 and 35 and its associated booster cylinder 32 or 34 constitutes an annular orifice of variable length which performs two different functions during the time power piston 13 comes to rest and reverses direction.
- the annular orifice restricts flow from the cylinder to the adjacent working space 14 or 15, and thereby permits development of the amplified pressure required to effect shifting of distributing valve 16.
- the annular orifice permits fluid transfer from the adjacent working space to the booster cylinder, and thus serves to maintain in the associated actuating motor 23 or 24 a pressure sufficient to insure that valve 16 will be maintained in its new position.
- valve 16 When pump 19 is at rest, or the supply of fluid to the oscillator is otherwise interrupted, spring 22 holds valve 16 in the illustrated position. Therefore, as soon as the supply of fluid is resumed, working spaces 14 and immediately will be pressurized and vented, respectively. If, at this instant, piston 13 is in an intermediate position, such as the one shown in FIG. 1, it will commence to move to the right. During the initial phase of this movement, a portion of the oil delivered to working space 14 escapes to tank 21 through a pilot path comprising booster cylinder 32, port 27, passage 25, port 28, booster cylinder 34, working space 15 and port 18. Because of the presence of restriction 26, this pilot flow develops in motor 23 a backpressure of a magnitude sufficient to enable it to overpower the larger motor 24 and to maintain valve 16 in the illustrated position.
- booster piston 35 enters cylinder 34 to thereby isolate the cylinder from free communication with working space 15 and develop therein an amplifled pressure which is approximately equal to-the product of the pressure in working space 14 and the ratio of the effective area of piston 13 to the effective area of piston 35.
- Oil displaced from cylinder 34 is delivered to working space 14 via port 28, passage 25, port 27, and booster cylinder 32, so now restriction 26 causes actuating motor 24 to be subjected to a higher pressure than motor 23.
- This pressure differential coupled with the differential between the effective areas of the two motors, enables motor 24 to shift valve 16 to its other operative position and thereby reverse the connections between pump 19 and tank 21 and the working spaces.
- power piston 13 is brought to a cushioned stop by booster unit 31. Therefore, since working spaces 14 and 15 are now vented and pressurized, respectively, power piston 13 commences to move to the left.
- booster piston 33 enters cylinder 32 to thereby bring the power piston to a cushioned stop and displace oil through port 27 at the amplified pressure mentioned earlier.
- This oil flows to working space 15 via passage 25, port 28, and booster cylinder 34, and consequently restriction 26 subjects motor 23 to a pressure higher than the supply pressure prevailing in motor 24.
- the pressure difference is sufficient to offset the area differential between the two motors, so valve 16 now is shifted back to its illustrated position. This action has the effect of pressurizing working space 14 and venting working space 15, and therefore power piston 13 will now commence to move to the right.
- the power piston 13 will continue to oscillate in the manner described as long as the oscillator continues to receive oil from pump 19.
- the frequency of the oscillator obviously will be determined by the rate at which oil is supplied.
- the distributing valve 16 also serves as a flow divider whose proportioning action can be varied.
- the valve comprises a bore 36 which is provided with a central supply port 37, a pair of exhaust or return ports 38 and 39, and a pair of motor ports 41 and 42, and which contains a reciprocable valve spool 43 formed with two axially spaced peripheral grooves 44 and 45 which define three lands 46, 47 and 48.
- the two operative positions of spool 43 are defined by a pair of stop members 49 and 51 which are screwed into the casing of the oscillator and are held in their selected positions by nylon thread locks 52.
- motor port 41 is isolated from return port 38 by land 46 and is connected in free communication with supply port 37 by groove 44, and motor port 42 is in free communication with return port 39 through groove 45 and is in restricted communication with supply port 37 across the right edge 53 of land 47.
- motor port 41 is isolated from return port 38 by land 46 and is connected in free communication with supply port 37 by groove 44
- motor port 42 is in free communication with return port 39 through groove 45 and is in restricted communication with supply port 37 across the right edge 53 of land 47.
- restriction 26 in the in terconnection 25 between the valve-actuating motors 23 and 24 in FIG. 2 takes the form of a plug 55 containing three orifices 56, 57 and 58 of different sizes.
- the plug is rotated by a knob 59 to any one of three positions determined by a detent 61 in order to interpose the selected orifice in passage 25.
- the adjustability of restriction 26 is a desirable feature in a commercial oscillator because it affords control over the peak snubbing pressure and the rate of deceleration of power piston 13 afforded by the booster units 29 and 31, and thus enables a single oscillator design to actuate loads of different magnitudes.
- the adjustable flow-splitting action which characterizes the distributing valve of the FIG. 2 embodiment also is afforded by the alternative version of valve 16 shown in FIG. 4.
- the spool 143 used in this valve differs from its FIG. 2 counterpart in that it employs a central land 147 whose opposed edges 153 and 154 lie in planes inclined in opposite directions with respect to the longitudinal axis of the spool.
- the rotary position of the spool rather than the axial positions of its limit stops 149 and 151, determines the degree of restriction in the diversion paths leading from supply port 137 to return ports 138 and 139 in the two operative positions of the spool.
- the rotary position of spool 143 is varied by a knob 62 which is connected with the spool through a torque-transmitting connection comprising stop 151, slot 63 and cooperating pin 64, the piston of actuating motor 24, and a pin 65 whose ends are received in aligned bores extending through the hollow land 148 of the valve spool.
- a detent 66 which cooperates with a circumferential series of holes in knob 62, serves to yieldingly hold the valve spool in the selected rotary position.
- the angles of inclination of edges 153 and 154 are equal, and therefore manipulation of knob 62 simultaneously effects the same change in the flow-splitting action afi'orded in both operative positions of valve 16. Aside from this, the FIG. 4 valve operates in the same way as its FIG. 2 counterpart.
- a hydraulic oscillator comprising a. a double-acting motor having a power element movable in a first direction under the action of fluid pressure in one working space and in a second direction under the action of fluid pressure in a second, opposed working space;
- a four-way distributing valve movable between a first position in which it establishes a supply path leading from an inlet connection to said one working space and a return path leading from said second working space to an exhaust connection, and a second position in which it reverses the connections between said paths and working spaces;
- c. means biasing the distributing valve towards the first position
- valve-actuating motors having unequal effective areas and acting on the distributing valve in oppositon to each other, the larger motor serving to shift the valve toward the second position;
- first booster pumping means including a first booster cylinder connected with the second working space and with the larger valve-actuating motor, a first pumping member operated by the power element for restricting the connection between the first booster cylinder and the second working space during a terminal portion of movement of the power element in said first direction for forcing fluid from the first booster cylinder to the larger valve-actuating motor during said terminal portion of movement;
- second booster pumping means including a second booster cylinder connected with the first working space and with the smaller valve-actuating motor, a second pumping member operated by the power element for restricting the connection between the second booster cylinder and the first working space during a terminal portion of movement of the power element in said second direction for forcing fluid from the second booster cylinder to the smaller valve-actuating motor during said terminal portion of movement;
- a hydraulic oscillator as defined in claim 2 in which the distributing valve maintains said diversion path open, but reduces the restriction to flow through it, as it moves between said first and second positions.
- a hydraulic oscillator as defined in claim 2 including adjustable means for varying the restriction to flow through the diversion path.
- a spool reciprocable in the bore and formed with two axially spaced peripheral grooves which define a central land and a pair of end lands,
- the first intermediate passage in said first position, is isolated from free communication with the adjacent end passage by one end land and is in unrestricted communication with the central passage through one peripheral groove, and the second intermediate passage is in unrestricted communication with the adjacent end passage through the other peripheral groove and is in restricted communication with the central passage across one edge of the central land, and 2. in said second position, the first intermediate passage is in unrestricted communication with the adjacent end passage through one groove and is in restricted communication with the central passage of the central land, and the second intermediate passage is isolated from free communication with the adjacent end passage by the other end land and is in unrestricted communication with the central passage through the other peripheral groove.
- a hydraulic osciallator as defined in claim 5 in which a. the edges at opposite sides of the central land lie in planes normal to the longitudinal axis of the spool;
- the distributing valve includes adjustable stops which cooperate with the spool to define said first and second positions
- a hydraulic oscillator as defined in claim 5 in which a. the edges at opposite sides of the central land lie in planes which are inclined in opposite directions with respect to the longitudinal axis of the spool; and
- distributing valve includes adjustment means for rotating the spool about its longitudinal axis and for locking it in a selected rotary position
- a hydraulic oscillator as defined in claim 1 which includes means for varying the restriction in flow through the transfer passage.
- a hydraulic oscillator as defined in claim 8 in which the transfer passage is restricted by a transverse orifice member which is pierced by a plurality of bores of different diameters, and which is movable to predetermined positions in each which flow through the transfer passage is restricted by a different bore.
- a hydraulic oscillator as defined in claim 1 in which a. the double-acting motor includes a power cylinder containing a conforming reciprocable power piston which divides it into said opposed working spaces; and
- each booster pumping means comprises a booster cylinder which is aligned with and has a smaller diameter than the power cylinder, and a booster piston carried by the power piston and which serves as the pumping member of the booster means P p g,
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
- Apparatuses For Generation Of Mechanical Vibrations (AREA)
Abstract
Description
Claims (11)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US25351472A | 1972-05-15 | 1972-05-15 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3786723A true US3786723A (en) | 1974-01-22 |
Family
ID=22960597
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00253514A Expired - Lifetime US3786723A (en) | 1972-05-15 | 1972-05-15 | Hydraulic oscillator |
Country Status (4)
Country | Link |
---|---|
US (1) | US3786723A (en) |
JP (1) | JPS5216557B2 (en) |
CA (1) | CA969067A (en) |
DE (1) | DE2261578A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3969987A (en) * | 1974-11-11 | 1976-07-20 | Hydroacoustics Inc. | Hydroacoustic apparatus and valving mechanisms for use therein |
US4056123A (en) * | 1973-09-26 | 1977-11-01 | Nihon Spindle Seizo Kabushiki Kaisha | Hydraulic oscillator |
US5787786A (en) * | 1996-05-09 | 1998-08-04 | Sauer-Sundstrand - Control Concepts | Dual hydraulic oscillator for the reciprocating cutter of an agricultural machine |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0225249Y2 (en) * | 1985-03-19 | 1990-07-11 |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1057701A (en) * | 1911-11-07 | 1913-04-01 | Ingersoll Rand Co | Valve-motion for percussive tools. |
US1384216A (en) * | 1920-08-13 | 1921-07-12 | Ingersoll Rand Co | Rock-drill |
US1662576A (en) * | 1925-09-15 | 1928-03-13 | Demag Ag | Valve for pneumatic tools |
GB784684A (en) * | 1954-08-31 | 1957-10-16 | George Stephen Kammer | Improvements in reciprocating motors for actuation by a fluid supplied at substantially constant pressure |
US2932175A (en) * | 1956-10-30 | 1960-04-12 | Herrick L Johnston Inc | Pressure generator for liquefied gas |
US2970579A (en) * | 1959-11-23 | 1961-02-07 | Tomlon Corp | Hydraulic reversing control |
-
1972
- 1972-05-15 US US00253514A patent/US3786723A/en not_active Expired - Lifetime
- 1972-11-15 CA CA156,526A patent/CA969067A/en not_active Expired
- 1972-12-15 DE DE19722261578 patent/DE2261578A1/en active Pending
-
1973
- 1973-01-10 JP JP48005813A patent/JPS5216557B2/ja not_active Expired
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1057701A (en) * | 1911-11-07 | 1913-04-01 | Ingersoll Rand Co | Valve-motion for percussive tools. |
US1384216A (en) * | 1920-08-13 | 1921-07-12 | Ingersoll Rand Co | Rock-drill |
US1662576A (en) * | 1925-09-15 | 1928-03-13 | Demag Ag | Valve for pneumatic tools |
GB784684A (en) * | 1954-08-31 | 1957-10-16 | George Stephen Kammer | Improvements in reciprocating motors for actuation by a fluid supplied at substantially constant pressure |
US2932175A (en) * | 1956-10-30 | 1960-04-12 | Herrick L Johnston Inc | Pressure generator for liquefied gas |
US2970579A (en) * | 1959-11-23 | 1961-02-07 | Tomlon Corp | Hydraulic reversing control |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4056123A (en) * | 1973-09-26 | 1977-11-01 | Nihon Spindle Seizo Kabushiki Kaisha | Hydraulic oscillator |
US3969987A (en) * | 1974-11-11 | 1976-07-20 | Hydroacoustics Inc. | Hydroacoustic apparatus and valving mechanisms for use therein |
US5787786A (en) * | 1996-05-09 | 1998-08-04 | Sauer-Sundstrand - Control Concepts | Dual hydraulic oscillator for the reciprocating cutter of an agricultural machine |
Also Published As
Publication number | Publication date |
---|---|
CA969067A (en) | 1975-06-10 |
DE2261578A1 (en) | 1973-11-29 |
JPS4925363A (en) | 1974-03-06 |
JPS5216557B2 (en) | 1977-05-10 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: CONTINENTAL ILLINOIS NATIONAL BANK AND TRUST COMPA Free format text: SECURITY INTEREST;ASSIGNOR:ICM ACQUISTIONS INC.;REEL/FRAME:004819/0654 Effective date: 19870911 |
|
AS | Assignment |
Owner name: CONTINENTAL ILLINOIS NATIONAL BANK AND TRUST COMPA Free format text: SECURITY INTEREST;ASSIGNOR:ICM ACQUISITIONS, INC., A CORP. OF DE;REEL/FRAME:005156/0501 Effective date: 19870911 |
|
AS | Assignment |
Owner name: ICM ACQUISITIONS, INC., A DE. CORP. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:GENERAL SIGNAL CORPORATION, A NY CORP.;REEL/FRAME:004855/0124 Effective date: 19870911 Owner name: HYDRECO, INC. Free format text: CHANGE OF NAME;ASSIGNOR:ICM ACQUISTIONS INC.;REEL/FRAME:004854/0821 Effective date: 19870910 |