US3385170A - Selector valve for a hydraulic circuit - Google Patents
Selector valve for a hydraulic circuit Download PDFInfo
- Publication number
- US3385170A US3385170A US508236A US50823665A US3385170A US 3385170 A US3385170 A US 3385170A US 508236 A US508236 A US 508236A US 50823665 A US50823665 A US 50823665A US 3385170 A US3385170 A US 3385170A
- Authority
- US
- United States
- Prior art keywords
- feed mechanism
- under pressure
- fluid under
- valve
- common supply
- 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
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B47/00—Drives or gearings; Equipment therefor
- B24B47/02—Drives or gearings; Equipment therefor for performing a reciprocating movement of carriages or work- tables
- B24B47/06—Drives or gearings; Equipment therefor for performing a reciprocating movement of carriages or work- tables by liquid or gas pressure only
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
- F15B2211/20592—Combinations of pumps for supplying high and low pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30505—Non-return valves, i.e. check valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/305—Directional control characterised by the type of valves
- F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/32—Directional control characterised by the type of actuation
- F15B2211/329—Directional control characterised by the type of actuation actuated by fluid pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/30—Directional control
- F15B2211/355—Pilot pressure control
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/405—Flow control characterised by the type of flow control means or valve
- F15B2211/40507—Flow control characterised by the type of flow control means or valve with constant throttles or orifices
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/405—Flow control characterised by the type of flow control means or valve
- F15B2211/40576—Assemblies of multiple valves
- F15B2211/40584—Assemblies of multiple valves the flow control means arranged in parallel with a check valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/42—Flow control characterised by the type of actuation
- F15B2211/421—Flow control characterised by the type of actuation mechanically
- F15B2211/423—Flow control characterised by the type of actuation mechanically manually, e.g. by using a lever or pedal
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/42—Flow control characterised by the type of actuation
- F15B2211/426—Flow control characterised by the type of actuation electrically or electronically
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/45—Control of bleed-off flow, e.g. control of bypass flow to the return line
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/505—Pressure control characterised by the type of pressure control means
- F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
- F15B2211/50536—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using unloading valves controlling the supply pressure by diverting fluid to the return line
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
- F15B2211/5151—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source and a directional control valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/50—Pressure control
- F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief valve
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/60—Circuit components or control therefor
- F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
- F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve means
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
- F15B2211/7051—Linear output members
- F15B2211/7053—Double-acting output members
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/78—Control of multiple output members
- F15B2211/783—Sequential control
Definitions
- the valve which disconnects the feed mechanism from the supply of fluid which continues to provide a traverse movement acts to connect the feed mechanism with a relatively low volume supply of fluid under pressure.
- the lower pressure and volume are sufficient to hold the grinding wheel in grinding position and also to actuate the portion of the feed mechanism which acts through the hand wheel shaft to advance the grinding wheel a short distance at a rate suitable for grinding. Thereafter, when the traverse mechanism is reversed, a momentary increase in pressure which normally occurs at the reversal point will not be transmitted to the feed mechanism.
- an object of the present invention to prevent undesired relative transverse movement between a grinding wheel and a workpiece at the reversal point of the longitudinal movement.
- Another object is to disconnect the transverse moving means from the common supply of fluid under pressure after the grinding wheel has been advanced to operative position.
- Another object is to provide means for disconnecting the transverse moving means from one source of fluid under pressure and connecting said means to another source of fluid under pressure.
- the drawing is a hydraulic diagram.
- the means for causing the relative longitudinal movement between a workpiece and a grinding wheel consists of a cylinder 10 attached to work carriage 11. Piston 12 slidably mounted in cylinder 10 is connected through piston rods 13 and 14 and support members 15 and 16 to the machine bed 17.
- the means for effecting the transverse movement consists of a cylinder 30 in bed 17.
- Piston 31 is slidably mounted in cylinder 30.
- Piston 31 has a piston rod 32 which, in turn, has a feed screw portion 35 with threads engaging a worm wheel 36 in grinding wheel support 40.
- Worm wheel 36 is mounted at the lower end of vertical shaft 37 in wheel support 49.
- At the top of shaft 37 there is another Worm wheel 38 in operative relation with worm gear 39.
- Worm gear 39 is part of shaft having a hand wheel 46 mounted thereon.
- Shaft 45 also has a pinion 47 in operative relation with rack 48.
- Rack 48 is also a piston rod for slow feed piston 50 slidably mounted in cylinder 51.
- the means for controlling the longitudinal movement consists essentially of a reversing valve and a start and stop valve 61 in valve housing 62.
- Start and stop valve 61 also performs the functions of cushioning the start of the longitudinal movement and lay-passing the reversing valve 60 when it is desired to effect the longitudinal movement manually.
- An exhaust line B is connected to all points in the hydraulic system requiring drainage or eX- haust.
- Operation The operation of the machine is initiated by energizing infeed solenoid 1, shifting infeed valve 65 to the left and directing fluid under pressure from pump #1 through the selector valve 66 and then to the head end of rapid feed cylinder 30.
- Rapid feed piston 31 advances the grinding wheel support 40 until said piston reaches the end of its stroke, i.e. when feed screw portion 35 engages positive stop 42.
- Valve 67 is then shifted to the left by spring 68 and directs fluid under pressure from pump #2 to the head end of slow feed cylinder 51 and also to the left end of valve 66, shifting valve 66 to the right.
- valve 66 shuts off the supply of fluid under pressure from valve 65 to the head end of rapid feed cylinder 30, and connects cylinder 30 with fluid under pressure from pump #2.
- piston 31 Since piston 31 is in its most advanced position, it requires only a small volume of fluid to provide pressure to hold said piston and the grinding wheel support 40 firmly in advanced position and to advance the slow feed piston 50.
- Disconnecting feed cylinders 30 and 51 from pump #1 makes the feed mechanism free of fluctuations in pressure which occur during the traverse movement of carriage 11, particularly at reversal.
- valve 71 connects pressure line 75 to direct fluid under pressure through throttle valve 76 to the left hand end of start and stop valve 61 to start the traverse movement of carriage 11.
- the means for disconnecting said feed mechanism from said common supply of fluid under pressure being a valve operable in one position to connect said feed mechanism and said traverse motor with said common supply of fluid under pressure and in another position to connect said feed mechanism with another supply of fluid under pressure while maintaining the connection between said common supply of fluid under pressure and said traverse motor.
- the means for disconnecting said feed mechanism from the common supply of fluid under pressure being a valve actuated by exhaust pressure from said feed mechanism and normally held by said exhaust pressure in position to connect both the feed mechanism and the traverse motor to said common supply of fluid under pressure.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Constituent Portions Of Griding Lathes, Driving, Sensing And Control (AREA)
- Grinding Of Cylindrical And Plane Surfaces (AREA)
- Fluid-Pressure Circuits (AREA)
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US508236A US3385170A (en) | 1965-11-17 | 1965-11-17 | Selector valve for a hydraulic circuit |
SE15306/66A SE321878B (nl) | 1965-11-17 | 1966-11-09 | |
DE19661577405 DE1577405A1 (de) | 1965-11-17 | 1966-11-12 | Schleifmaschine |
DEL43423U DE1953513U (de) | 1965-11-17 | 1966-11-12 | Schleifmaschine. |
GB51110/66A GB1127838A (en) | 1965-11-17 | 1966-11-15 | Improvements in and relating to grinding machines |
CH1653366A CH450204A (fr) | 1965-11-17 | 1966-11-15 | Machine à rectifier |
NL6616198A NL6616198A (nl) | 1965-11-17 | 1966-11-17 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US508236A US3385170A (en) | 1965-11-17 | 1965-11-17 | Selector valve for a hydraulic circuit |
Publications (1)
Publication Number | Publication Date |
---|---|
US3385170A true US3385170A (en) | 1968-05-28 |
Family
ID=24021922
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US508236A Expired - Lifetime US3385170A (en) | 1965-11-17 | 1965-11-17 | Selector valve for a hydraulic circuit |
Country Status (6)
Country | Link |
---|---|
US (1) | US3385170A (nl) |
CH (1) | CH450204A (nl) |
DE (2) | DE1953513U (nl) |
GB (1) | GB1127838A (nl) |
NL (1) | NL6616198A (nl) |
SE (1) | SE321878B (nl) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2103530A (en) * | 1935-09-05 | 1937-12-28 | Maine Steel Inc | System of equalizing the lifting speed of differently loaded hydraulic jacks |
US2277640A (en) * | 1938-06-03 | 1942-03-24 | Vickers Inc | Power transmission |
US2659204A (en) * | 1950-11-18 | 1953-11-17 | Siam | Hydraulic power system |
-
1965
- 1965-11-17 US US508236A patent/US3385170A/en not_active Expired - Lifetime
-
1966
- 1966-11-09 SE SE15306/66A patent/SE321878B/xx unknown
- 1966-11-12 DE DEL43423U patent/DE1953513U/de not_active Expired
- 1966-11-12 DE DE19661577405 patent/DE1577405A1/de active Pending
- 1966-11-15 CH CH1653366A patent/CH450204A/fr unknown
- 1966-11-15 GB GB51110/66A patent/GB1127838A/en not_active Expired
- 1966-11-17 NL NL6616198A patent/NL6616198A/xx unknown
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2103530A (en) * | 1935-09-05 | 1937-12-28 | Maine Steel Inc | System of equalizing the lifting speed of differently loaded hydraulic jacks |
US2277640A (en) * | 1938-06-03 | 1942-03-24 | Vickers Inc | Power transmission |
US2659204A (en) * | 1950-11-18 | 1953-11-17 | Siam | Hydraulic power system |
Also Published As
Publication number | Publication date |
---|---|
SE321878B (nl) | 1970-03-16 |
GB1127838A (en) | 1968-09-18 |
NL6616198A (nl) | 1967-05-18 |
DE1953513U (de) | 1967-01-12 |
DE1577405A1 (de) | 1970-01-15 |
CH450204A (fr) | 1968-01-15 |
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