US3635442A - Air balancer safety system - Google Patents

Air balancer safety system Download PDF

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Publication number
US3635442A
US3635442A US3635442DA US3635442A US 3635442 A US3635442 A US 3635442A US 3635442D A US3635442D A US 3635442DA US 3635442 A US3635442 A US 3635442A
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US
United States
Prior art keywords
pressure
air supply
air
hoist
regulator valve
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
Application number
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English (en)
Inventor
Otmar M Ulbing
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ingersoll Rand Co
Original Assignee
Ingersoll Rand Co
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Filing date
Publication date
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Publication of US3635442A publication Critical patent/US3635442A/en
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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
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/05—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed specially adapted to maintain constant speed, e.g. pressure-compensated, load-responsive
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
    • B66D1/00—Rope, cable, or chain winding mechanisms; Capstans
    • B66D1/02—Driving gear
    • B66D1/08—Driving gear incorporating fluid motors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
    • B66D2700/00—Capstans, winches or hoists
    • B66D2700/01—Winches, capstans or pivots
    • B66D2700/0125—Motor operated winches
    • B66D2700/0133—Fluid actuated
    • 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
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/30565—Assemblies of multiple valves having multiple valves for a single output member, e.g. for creating higher valve function by use of multiple valves like two 2/2-valves replacing a 5/3-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
    • F15B2211/35—Directional control combined with flow 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
    • F15B2211/30—Directional control
    • F15B2211/35—Directional control combined with flow control
    • F15B2211/353—Flow control by regulating means in return line, i.e. meter-out 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
    • F15B2211/70—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
    • F15B2211/7052—Single-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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/863—Control during or prevention of abnormal conditions the abnormal condition being a hydraulic or pneumatic failure
    • F15B2211/8633—Pressure source supply failure
    • 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/863—Control during or prevention of abnormal conditions the abnormal condition being a hydraulic or pneumatic failure
    • F15B2211/8636—Circuit failure, e.g. valve or hose failure
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/7722—Line condition change responsive valves
    • Y10T137/7781—With separate connected fluid reactor surface
    • Y10T137/7793—With opening bias [e.g., pressure regulator]
    • Y10T137/7801—Balanced valve

Definitions

  • This piston member also interconnects the main air supply chamber of the regulator valve with the pilot air 3,325,148 6/1967 POWGll X chamber 50 that an operator can use the control member to 3,457,837 7/1969 Powell 354/186 X slowly lower the load after the failure of the air supply without 3,485,259 12/1969 Ulbmg 1 37/505. 1 8 waiting f the repair f h i Supply 2,940,462 6/1960 Johanson ..137/508 AIR SUPPLY 3 4 Claims, 2 Drawing Figures PATENTED JAN] 8 m2 3.535442 AIR SUPPLY 39 FIG. I
  • This invention relates to a control system and mechanism for operating and controlling a balancing hoist containing a fluid pressure operated member for balancing a load supported by the hoist.
  • a hoist of this general type is disclosed in my U.S. Pat. No. 3,421,737, granted Jan. 14, 1969.
  • the principal object of this invention is to provide a novel balancing hoist control system which overcomes the above danger provided by the conventional balancing hoist control system.
  • a control system including an air supply, a pilot-operated regulator valve having a main inlet connected to the air supply, a main outlet connected to the hoist member for supplying the hoist member with a controlled air pressure, a pilot port adapted to receive a pilot air pressure for controlling the regulator valve and causing it to supply air pressure to the hoist member in response to the pilot air pressure and a control member connected to the air supply and to the pilot port to supply the pilot port with a variable pilot air pressure.
  • a check valve is located between the main inlet in the regulator valve and the air supply and is operative, in response to a drop in pressure of said air supply, to seal the main inlet from the air supply.
  • a member is operative, in response to a drop in pressure in the air supply, to prevent the regulator valve from exhausting pressure from its main outlet.
  • the control system further includes a valve means which is operative, in response to a drop in pressure of the air supply, to interconnect the main outlet to the pilot port so that the operator can use the control member for bleeding pressure from the hoist member at a controlled rate to slowly lower the load in the hoist.
  • FIG. 1 is a combination schematic view and fragmentary sectional view of the control system of the invention with the regulator valve and surrounding portions shown in section;
  • FIG. 2 is an enlarged fragmentary view of the sectional portion of FIG. 1 showing the air-operated piston in an alternate position wherein the regulator valve is prevented from its normal operation.
  • the balancing hoist 1 schematically shown in FIG. I includes an outer casing 2 which may be supported on a suitable overhead support, a hoist drum 3 contained in the casing 2 and mounted to rotate and simultaneously reciprocate therein in a controlled manner, and a hoisting cable 4 wound around the drum 3 with the portion depending from the drum and connected to a suitable load 5.
  • the drum 3 is controlled by an air chamber 6 formed in the hoist. Air pressure in the chamber 6 opposes the weight of the load 5.
  • a lbalancing hoist of this type is conventional and is fully described in my U.S. Pat. No. 3,421,737, and, therefore, is not further described in this application.
  • the air chamber 6 is connected by the passage 7 to the main outlet 8 of a pilot-operated regulator valve 9 which is shown in section in FIGS. 1 and 2.
  • the regulator valve 9 includes a housing 10 which normally is attached to the casing 2 of the hoist 1.
  • the regulator valve 9 further includes a main inlet and a pilot port 12.
  • the regulator valve 9 also includes a main outlet chamber 14, an air supply chamber 115, and a pilot air chamber 16. Each of these chambers is separated from the others by a pair of diaphragms 21 and 22.
  • the first diagram 21 separates the main air outlet chamber 14 from the air supply chamber 1.5, while the second diaphragm 22 separates the air supply chamber 15 from the pilot air chamber 16.
  • the main air outlet chamber 14 communicates with the main air supply chamber 15 through a supply valve opening 23.
  • the main outlet chamber 14 communicates with the atmosphere through an exhaust valve opening 24.
  • the supply valve opening 23 is mounted on a movable valve member 25 which is supported on the housing I0 of the regulator valve 9 by the respective first and second diaphragms 21 and 22.
  • the valve member 25 is free to move up and down in response to air pressures acting on the diaphragms 21 and 22.
  • the valve member 25 further carries a valve plug 26 which is movably mounted on the valve member 25 by a smaller diaphragm 27.
  • the valve plug 26 is adapted to seat on the seats of both the supply valve opening 23 and the exhaust valve opening 24. As shown in FIG. 1, the valve plug 26 is seated on and closing both the valve openings 23 and 24.
  • the schematic diagram in FIG. 1 further contains an air supply 30 supplying air through a main air pipe 31.
  • Air pressure is supplied from the main inlet 11 to a smaller air line 32 which contains an adjustable throttle valve 33 for throttling and reducing the air pressure flowing through the line 32.
  • the pilot air line 32 connects to the pilot port 12 of the regulator valve 9 and also to a control member 35.
  • the control member 35 vents or exhausts the air pressure at the pilot port 12 at a controlled pressure to maintain the pilot pressure in the pilot air chamber 16 at a predetermined selected value.
  • the control member is adjusted by the operator to provide the desired pilot pressure.
  • a control member for accomplishing this job is shown and described in my aforementioned U.S. Pat. No. 3,421,737.
  • a spring-operated check valve 37 is located between the main air pipe 31 and the main inlet 11.
  • the check valve 37 allows the air supply to flow forwardly into the main inlet 11 but automatically prevents a counterflow of air from the main inlet 11 to the main air pipe 31.
  • the check valve 37 includes a conventional check ball, also designated 37, and a spring 38 urging the check ball 37 against a seat.
  • the housing further includes a piston 40 having a front face 41 subject to the pressure in the main air pipe 31 and a rear face 42 subject to the air pressure in the main inlet 11.
  • a passage 43 extends between the rear face 42 of the piston 40 and the main inlet 11.
  • the piston 40 carries a plunger 45 which extends through a bore 46 and terminates in a shoe 47.
  • the shoe 47 is adapted to engage the rear of the regulator valve 9 as shown in FIG. 2
  • the shoe 47 holds the regulator valve 9 from moving through its normal operation. Also in the FIG. 2 position, the supply valve opening 23 is open and the exhaust valve opening 24 is closed. This prevents the regulator valve-from opening the exhaust valve opening 24 to exhaust the pressure from the main outlet chamber 14, which otherwise would occur if the pressure of the air supply 30 failed suddenly, while the air supply chamber communicates with the main outlet chamber 14.
  • the valve plunger 45 also forms a valve which connects the main inlet 11 to the pilot air chamber 16 if and when the air 1 supply pressure fails.
  • the main inlet 11 connects to a passage 48 which extends into a valve cavity 49 in the bore 46 surrounding a reduced portion 50 of the plunger 45.
  • the plunger carries O-rings 51 located on the opposite sides of the cavity 49 so as to seal the cavity 49 from the pilot air chamber 16 when the plunger 45 is in its inoperative position, shown in FIG. 1.
  • the plunger 45 moves forwardly against the regulator valve 9, as shown in FIG. 2
  • its reduced portion moves into the pilot air chamber 16 to open the cavity 49 into the pilot air chamber 16.
  • the air pressure in the main inlet 11 flows into the pilot air chamber 16 to act on the rear of the regulator valve 9 to aid the shoe 47 in holding the regulator valve in its nonoperative position, as shown in FIG. 2.
  • a balancing hoist control system for operating and controlling a balance hoisthaving a pressure-operated member for balancing a load on the hoist, said control system comprising:
  • a pilot-operated regulator valve having a main inlet connected to said air supply, a main outlet connected to said hoist member for supplying said hoist member with a controlled air pressure, and a pilot port adapted to receive a pilot air pressure for controlling the regulator valve and causing it to supply air pressure to said hoist member in response to the pilot air pressure; a control member connected to said pilot port to supply said pilot port with a controlled variable pilot air pressure;
  • a check valve located between said main inlet in said regulator valve and said air supply and operative to seal said main inlet from said air supply in the event of a drop in pressure in said air supply;
  • valve means operative, in response to a substantial drop in pressure of said air supply, to connect said main outlet to said pilot port whereby an operator can use said control member to bleed pressure from said hoist member at a controlled rate to slowly lower a load in the event of the failure of said air supply.
  • said means for preventing said regulator valve from exhausting pressure from said main outlet in the event of a substantial drop in pressure in said air supply includes a piston operative, in response to the appearance of a differential pressure across the check valve, to move to a position preventing said regulator valve from exhausting pressure from said main outlet.
  • said piston also includes said valve means for connecting said main outlet to said pilot port in response to a substantial drop in pressure of said air supply.
  • said regulator valve includes a diaphragm and said piston is operative to engage said diaphragm to prevent it from moving.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Self-Closing Valves And Venting Or Aerating Valves (AREA)
  • Fluid-Pressure Circuits (AREA)
US3635442D 1969-10-08 1969-10-08 Air balancer safety system Expired - Lifetime US3635442A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US86483269A 1969-10-08 1969-10-08

Publications (1)

Publication Number Publication Date
US3635442A true US3635442A (en) 1972-01-18

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ID=25344170

Family Applications (1)

Application Number Title Priority Date Filing Date
US3635442D Expired - Lifetime US3635442A (en) 1969-10-08 1969-10-08 Air balancer safety system

Country Status (6)

Country Link
US (1) US3635442A (enrdf_load_stackoverflow)
BE (1) BE757251A (enrdf_load_stackoverflow)
DE (1) DE2047889A1 (enrdf_load_stackoverflow)
FR (1) FR2065218A5 (enrdf_load_stackoverflow)
GB (1) GB1289624A (enrdf_load_stackoverflow)
SE (1) SE377924B (enrdf_load_stackoverflow)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3747886A (en) * 1971-09-20 1973-07-24 Conco Inc Load balancer with safety control
US3788491A (en) * 1971-05-28 1974-01-29 Zimmerman D W Mfg Apparatus for moving an object along a predetermined path
US4807767A (en) * 1983-12-20 1989-02-28 Grumman Aerospace Corporation Self balancing electric hoist
WO1995019316A1 (en) * 1994-01-13 1995-07-20 D.W. Zimmerman Manufacturing, Inc. Balancing hoist and material handling system
US5848781A (en) * 1994-01-13 1998-12-15 Ingersoll-Rand Company Balancing hoist braking system
US5984276A (en) * 1998-09-29 1999-11-16 Tri-Motion Industries, Inc. Cable retraction speed limiter for air balancing hoist
US20040154667A1 (en) * 2003-01-30 2004-08-12 Steven Vitale Pressure regulator with tamper-proof safety feature
US20100108965A1 (en) * 2008-11-05 2010-05-06 Endo Kogyo Co., Ltd. Air balancer
US20120211709A1 (en) * 2007-07-10 2012-08-23 Givens Engineering Inc. Pneumatic multi-weight balancing device
US10843910B2 (en) 2017-09-13 2020-11-24 Ingersoll-Rand Industrial U.S., Inc. Electric powered pneumatic balancer
US11193703B1 (en) * 2017-05-10 2021-12-07 Equilibar, Llc Dome-loaded back pressure regulator with setpoint pressure energized by process fluid

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2940462A (en) * 1957-03-13 1960-06-14 Honeywell Regulator Co Pressure regulating valve
US3325148A (en) * 1965-12-27 1967-06-13 Edgar R Powell Pneumatically-operated hoist
US3457837A (en) * 1966-07-11 1969-07-29 Zimmerman D W Mfg Controller for pneumatically-operated hoists
US3485259A (en) * 1967-07-24 1969-12-23 Ingersoll Rand Co Pressure regulating valve

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2940462A (en) * 1957-03-13 1960-06-14 Honeywell Regulator Co Pressure regulating valve
US3325148A (en) * 1965-12-27 1967-06-13 Edgar R Powell Pneumatically-operated hoist
US3457837A (en) * 1966-07-11 1969-07-29 Zimmerman D W Mfg Controller for pneumatically-operated hoists
US3485259A (en) * 1967-07-24 1969-12-23 Ingersoll Rand Co Pressure regulating valve

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3788491A (en) * 1971-05-28 1974-01-29 Zimmerman D W Mfg Apparatus for moving an object along a predetermined path
US3747886A (en) * 1971-09-20 1973-07-24 Conco Inc Load balancer with safety control
US4807767A (en) * 1983-12-20 1989-02-28 Grumman Aerospace Corporation Self balancing electric hoist
WO1995019316A1 (en) * 1994-01-13 1995-07-20 D.W. Zimmerman Manufacturing, Inc. Balancing hoist and material handling system
US5522581A (en) * 1994-01-13 1996-06-04 Zimmerman International Corp. Balancing hoist and material handling system
US5848781A (en) * 1994-01-13 1998-12-15 Ingersoll-Rand Company Balancing hoist braking system
US5984276A (en) * 1998-09-29 1999-11-16 Tri-Motion Industries, Inc. Cable retraction speed limiter for air balancing hoist
US6923197B2 (en) 2003-01-30 2005-08-02 Keyspan Energy Pressure regulator with tamper-proof safety feature
US20040154667A1 (en) * 2003-01-30 2004-08-12 Steven Vitale Pressure regulator with tamper-proof safety feature
US20120211709A1 (en) * 2007-07-10 2012-08-23 Givens Engineering Inc. Pneumatic multi-weight balancing device
US8465005B2 (en) * 2007-07-10 2013-06-18 Givens Engineering Inc. Pneumatic multi-weight balancing device
US20100108965A1 (en) * 2008-11-05 2010-05-06 Endo Kogyo Co., Ltd. Air balancer
US8317161B2 (en) * 2008-11-05 2012-11-27 Endo Kogyo Co., Ltd. Air balancer
US11193703B1 (en) * 2017-05-10 2021-12-07 Equilibar, Llc Dome-loaded back pressure regulator with setpoint pressure energized by process fluid
US12270585B2 (en) 2017-05-10 2025-04-08 Equilibar, Llc Dome-loaded back pressure regulator with setpoint pressure energized by process fluid
US10843910B2 (en) 2017-09-13 2020-11-24 Ingersoll-Rand Industrial U.S., Inc. Electric powered pneumatic balancer

Also Published As

Publication number Publication date
DE2047889A1 (de) 1971-04-22
FR2065218A5 (enrdf_load_stackoverflow) 1971-07-23
GB1289624A (enrdf_load_stackoverflow) 1972-09-20
SE377924B (enrdf_load_stackoverflow) 1975-08-04
BE757251A (fr) 1971-03-16

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