[go: up one dir, main page]

US2452035A - Door operating mechanism for powder hoists - Google Patents

Door operating mechanism for powder hoists Download PDF

Info

Publication number
US2452035A
US2452035A US525964A US52596444A US2452035A US 2452035 A US2452035 A US 2452035A US 525964 A US525964 A US 525964A US 52596444 A US52596444 A US 52596444A US 2452035 A US2452035 A US 2452035A
Authority
US
United States
Prior art keywords
door
powder
operating mechanism
dog
operating
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
US525964A
Inventor
George A Chadwick
Philias H Girouard
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.)
Individual
Original Assignee
Individual
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US525964A priority Critical patent/US2452035A/en
Application granted granted Critical
Publication of US2452035A publication Critical patent/US2452035A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42AMMUNITION; BLASTING
    • F42BEXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B39/00Packaging or storage of ammunition or explosive charges; Safety features thereof; Cartridge belts or bags
    • F42B39/14Explosion or fire protection arrangements on packages or ammunition
    • YGENERAL 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
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T292/00Closure fasteners
    • Y10T292/08Bolts
    • Y10T292/0801Multiple
    • Y10T292/0848Swinging
    • Y10T292/0849Operating means
    • Y10T292/0853Link and lever

Definitions

  • the following disclosure relates to door closing and sealing means, and is particularly adapted for operating and sealing a swinging door at the upper end of a powder hoist for powder bags used in hea guns.
  • Fig. 1 is an end view of the door in open position, partly in section, with a. cross-sectional view of the upper end of the powder hoist trunk and of the powder cars therein, as well as the gun loading tray onto which the powder bags are rolled from the powder cars,
  • Fig. 2 is a side view of the door in closed position and the sealing dogs in position to seal the door tightly in place
  • Fig. 3 shows the detail structure and arrangement of the sealing dogs and the mechanism which operates them
  • Fig. 4 is a schematic illustration of the hydraulic system used in the control of the operating means for the opening and closing of the door and for the movement of the sealing dogs in the proper sequence with relation thereto.
  • the closing means illustrated consists of a swinging door I, hinged at its lower end at 39 and fixed frame 36, thereby compressing the door gasket 41 and forming a flame-tight seal.
  • the dogs are connected by an operating linkage to a second hydraulic cylinder l2, as shown more clearly in Fig. 3.
  • the means for controlling the operation of the door and the dogs consists of the hydraulic system shown schematically in Fig. 4. It comprises a pump it driven by an electric motor IS, a control valve 24, a door operating cylinder 2, a dog operating cylinder I2, and interconnecting piping as shown.
  • the door control valve handle 21 is shifted to and held by hand in its upper position. Oil under pressure will then be ported from the pump it through pipes l9 and 23, control valve 24, and pipe 29 to the lower end of the do operating cylinder l2.
  • the piston II will move upward, thereby rotating the dog operating linkage and unlocking the door.
  • the dog operating cylinder piston H will uncover a port for a pipe line 30 to convey the pressure to the upper end of the door operating cylinder 2.
  • the door operating piston 5 will then move down against the pressure of spring 34 and open the door.
  • the door control valve When the door is opened, the space between the powder car 4i and the gun loading tray 35 willbe bridged by the door, as shown in Fig. 1. It should be noted also that the port (defined by the door framing 36 of the trunk 40) and the hinge 39 for the door i is located at a higher elevation than the receiv- After the powder bags have-been removed from the powder car M (the car, as shown, will stop in two successive positions in order to unload both trays 42 and 43), the door control valve will be moved to and held manually in its lower position.
  • Oil under pressure from the pump will then be ported through the door control valve to the lower end of the door operating .cylinder 2 through pipe 33.
  • the door operating piston 5 will be moved upward, thereby closing the door. Near the end of the upward travel of the door operating piston,
  • the purpose of the door operated valve 63 is to prevent the porting of pressure for closing of the.
  • the door opens the valve; the door operated valve.
  • the spring at in the door operating cylinder is provided to approximately counterbalance the door.
  • a relief valve 20 is provided in the hydraulic circuit to limit the maximum pressure in the system.
  • the dog operating piston II is arranged for equal areas on both sides of the cylinder in order to have equal forces for opening and closing the dogs (the toggle linkage 6, l for operating the dogs moves past the dead center position in order to provide a more positive lock)
  • the control valve is arranged to equalize the pressures in opposite sides of the cylinders when released into neutral position so as to permit 4 including a trunk having a port therein, a hoistmanual operation of thedog linkage and the door in the event of failure of the hydraulic system, or the power supply to the electric motor.
  • Fig. 1 shows the powder car 4
  • the door operat-,
  • ing cylinder 2 is pivoted at 46 and the pipes 30, 32 and 33 have swivelled connections at this pivot to the portions connected to-a'nd movable with the cylinder. r
  • the dog operating cylinder I2 is pivotedat 59 where pipes 29, 30 and 3
  • the details of the dog operating mechanism may be seen in Fig. 3.
  • Thedogs 50 are pivoted at 38 and are all connected to move in unison by the links 54, 48, 55 and 56 and the bell cranks 5
  • Bell crank 52 has integral'lever 31 connected for operation to the linkage B, 1 which is actuated by piston rod 9 pivoted thereto at 58 in Fig. 3.
  • the piston rod may be connected to the pivot 51 between links 6 and 1 as shown in the schematic diagram, and the link 6 may be connecteddirectly tofone'of the, dog levers as shown in Fig. 4.
  • the dogs 50 operate against the wedges 6i, as shown in Fig. 2, to press the door tightly against the fixed frame 36, compressing the gasket 41 all the way around the door, thus forming a flametight seal. Suitable clearance isprovided in the hinges 39 to permit this. p
  • an ammunition hols 1Q including, a trunk and a car, a gun loading tray a door hinged at its bottom edge to the trunk am so constructed and arranged as to substantial]: bridge the space between the trunk andlahe loading tray when they door is open, fluid PI'CSSUI'i mechanism arranged to operate the door, sealing means arranged to secure the door to the trunk fluid pressure mechanism arranged to operate the sealing means, and a fluid pressure system including said mechanisms for sequently actuating said mechanisms both to release the sealing means prior to opening the door and to close thr door prior to fastening the sealing means.
  • an ammunition hoist including a trunk and a hoisting car, a gun loading tray, a door hinged at its bottom edge to th! trunk and so constructed and arranged as tc substantially bridge the space between the cal and the loading tray when the door is open; 2 dog coacting with the door to secure the door to the trunk, a dog operating mechanism actuated by a fluid under pressure, a door operating mechanism actuated by a fluid under pres- .sure, and a fluid pressure system including a control valve and said mechanisms arranged to sequentially actuate the dog operating mechanism prior to the door operating mechanism in opening the door and the door operating mechanism prior to the dog operating mechanism inclosing the door.
  • a fluidjpressure system comprising a dog operating mechanism, a door operating mechanism, means including a control valve for directing a fluid under pressure to first actuate one of said mechanisms, and means including said first actuated mechanism for further direct- ,ing the fluid to thereafter actuatethe other of said mechanisms, whereby the dog operating mechanism releases the dog prior to the operation of the door operating mechanism in opening the door and the door operating mechanism closes the door prior to the operation of the dog operating mechanism in fastening the dog to seal off the said port.
  • a fluidjpressure system comprising a dog operating mechanism, a door operating mechanism, means including a control valve for directing a fluid under pressure to first actuate one of said mechanisms, and means including said first actuated mechanism for further direct- ,ing the fluid to thereafter actuatethe other of said mechanisms, whereby the dog operating mechanism releases the dog prior to the operation of the door operating mechanism in opening the door and the door operating mechanism closes the door prior to the operation of the dog operating mechanism in fastening the dog to seal off the said port.
  • an ammunition hoist including a trunk and a hoisting car therein with a tiltable tray, a gun loading tray, a door on the trunk with a hinge at the bottom edge of the door located higher than loading tray, the door being so constructed and arranged as to substantially 9 bridge the space between the tiltable tray and the wedge on the outer side of and near an edge of 'aesaoss d the door, a dog pivotaliy attached to the trunk and movable against the wedge to press the gasket against the frame to form a flame tight seal, a dog operating piston and coacting cylinder provided with an outlet which is uncovered by the piston near the end of the dog releasing stroke, a door operating piston and coacting cylinder provided with an outlet which is uncovered by the piston near the end of the door closing stroke, the door operating piston and cylinder serving as a support for the door when open and having a spring counterbalancing the weight of the door, a source of fluid under substantially constant pressure, means including a single manually operable control valve to direct the fluid to one side

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Power-Operated Mechanisms For Wings (AREA)

Description

Ill 4) I II II ll/l I III III (5. A. CHADWICK EI'AL DOOR OPERATING MECHANISM FOR POWDER HOISTS Filed March 10, 1944 4 She'ets-Sheet 1 FIE. I v
INVENTORS 650065 A. MIDI/6K BY PMLA If. BIROIMRD ATT EY Get. 26, 194. s. A. CHADWICK EI'AL 2,452,035
DOOR OPERATING MECHANISM FOR POWDER HOISTS Filed March 10, 1944 4 Sheets-Sheet 3 mm m was. I m
INVENTORS GEORGE a. GHADIVIGK PHIL/A amaumo 0% 1943- e. A. CHADWICK EI'AL 2,452,935
DOOR OPERATING MECHANISM FOR POWDER HOISTS Filed March 10, 1944 4 Sheets-Sheet 4 INVEN1ORS GEORGE A. GHfiDW/CK BY PHIL/44$ H GIROUARD ATTOR Patented Oct. '26, 1948 DOOR OPERATING MECHANISM FOR I POWDER HOISTS George A. Chadwick, Den-on,- Mich and Philias H. Girouard, Washington, D. 0.
Application March 10, 1944, Serial No. 525,964
4 Claims. (01. 89-46) (Granted nnderthe act of March 3. 1883, as mended 'April so, 1928; 310 o. G. 157) The following disclosure relates to door closing and sealing means, and is particularly adapted for operating and sealing a swinging door at the upper end of a powder hoist for powder bags used in hea guns.
Th several objects of the device herein described are:
(a) To provide a means for closing the upper end of the powder trunk, while the powder car is in motion;
(b) To provide a flame-tight seal for the closing means;
(c) To provide a means for transferring the powder bags from the powder car trays to the gun loading tray;
(d) To provide an automatic means of controlling the closing means and the sealing means so that each operation occurs in th proper sequence.
The device is illustrated in its preferred form in the accompanying drawings, in which:
Fig. 1 is an end view of the door in open position, partly in section, with a. cross-sectional view of the upper end of the powder hoist trunk and of the powder cars therein, as well as the gun loading tray onto which the powder bags are rolled from the powder cars,
Fig. 2 is a side view of the door in closed position and the sealing dogs in position to seal the door tightly in place,
Fig. 3 shows the detail structure and arrangement of the sealing dogs and the mechanism which operates them, and
Fig. 4 is a schematic illustration of the hydraulic system used in the control of the operating means for the opening and closing of the door and for the movement of the sealing dogs in the proper sequence with relation thereto.
The closing means illustrated consists of a swinging door I, hinged at its lower end at 39 and fixed frame 36, thereby compressing the door gasket 41 and forming a flame-tight seal. The dogs are connected by an operating linkage to a second hydraulic cylinder l2, as shown more clearly in Fig. 3.
The means for controlling the operation of the door and the dogs consists of the hydraulic system shown schematically in Fig. 4. It comprises a pump it driven by an electric motor IS, a control valve 24, a door operating cylinder 2, a dog operating cylinder I2, and interconnecting piping as shown.
The operation of the hydraulic circuit is as follows: i
To open the door, the door control valve handle 21 is shifted to and held by hand in its upper position. Oil under pressure will then be ported from the pump it through pipes l9 and 23, control valve 24, and pipe 29 to the lower end of the do operating cylinder l2. The piston II will move upward, thereby rotating the dog operating linkage and unlocking the door. As soon as the dogs 50 have been rotated sufficiently to clear the door, the dog operating cylinder piston H will uncover a port for a pipe line 30 to convey the pressure to the upper end of the door operating cylinder 2. The door operating piston 5 will then move down against the pressure of spring 34 and open the door. When the door is opened, the operator releases the handle of the door control valve and it is returned to its neutral position by spring 26, thus unloading the pump discharge through the valve to the expansion tank I! via pipes 22 and 2|. An overload relief valve 20 i used in the line between the pump discharge pipe 2|.
operated by a hydraulic cylinder 2. When the door is opened, the space between the powder car 4i and the gun loading tray 35 willbe bridged by the door, as shown in Fig. 1. It should be noted also that the port (defined by the door framing 36 of the trunk 40) and the hinge 39 for the door i is located at a higher elevation than the receiv- After the powder bags have-been removed from the powder car M (the car, as shown, will stop in two successive positions in order to unload both trays 42 and 43), the door control valve will be moved to and held manually in its lower position.
' Oil under pressure from the pump will then be ported through the door control valve to the lower end of the door operating .cylinder 2 through pipe 33. The door operating piston 5 will be moved upward, thereby closing the door. Near the end of the upward travel of the door operating piston,
a port will be uncovered,.and the pressure will be I ported via. pipe 32 to the door operated Valve 13.
However, this pressure will be blocked by the valve l3 until the door is almost completely closed, at which time the pressure will be'ported move downward, thereby rotating the dog operatpipe l9 and return ing linkage and dogging the door. when the door is thus locked, the door control valve is released by the operator and is returned by spring 28 to its neutral position, thus unloading the pump discharge to th expansion tank through plpesi22= and-2i.
The purpose of the door operated valve 63 is to prevent the porting of pressure for closing of the.
dogs until the door is almost completely closed. Theoretically, the center port in the door operating cylinder will perform this function, but due to the actual arrangements of the door operating cylinder with respect to th door, .-the movement.
the door opens the valve; the door operated valve.
will therefore be opened only when the upperend of the door is very near its completely closed position.
The spring at in the door operating cylinder is provided to approximately counterbalance the door.
A relief valve 20 is provided in the hydraulic circuit to limit the maximum pressure in the system. The dog operating piston II is arranged for equal areas on both sides of the cylinder in order to have equal forces for opening and closing the dogs (the toggle linkage 6, l for operating the dogs moves past the dead center position in order to provide a more positive lock) The control valve is arranged to equalize the pressures in opposite sides of the cylinders when released into neutral position so as to permit 4 including a trunk having a port therein, a hoistmanual operation of thedog linkage and the door in the event of failure of the hydraulic system, or the power supply to the electric motor.
Fig. 1 shows the powder car 4| in its uppermost position with the lower powder tray 43 tilted to discharge the powder bag hoisted on it and thereby permit it to roll down the door I into the gun loading tray 35. The door operat-,
ing cylinder 2 is pivoted at 46 and the pipes 30, 32 and 33 have swivelled connections at this pivot to the portions connected to-a'nd movable with the cylinder. r
The dog operating cylinder I2 is pivotedat 59 where pipes 29, 30 and 3| have a swivelled connection to their movable portions incorporated in the body of the cylinder i2.
The details of the dog operating mechanism may be seen in Fig. 3. Thedogs 50 are pivoted at 38 and are all connected to move in unison by the links 54, 48, 55 and 56 and the bell cranks 5|, 52 and 53. Bell crank 52 has integral'lever 31 connected for operation to the linkage B, 1 which is actuated by piston rod 9 pivoted thereto at 58 in Fig. 3. The piston rod may be connected to the pivot 51 between links 6 and 1 as shown in the schematic diagram, and the link 6 may be connecteddirectly tofone'of the, dog levers as shown in Fig. 4. I
The dogs 50 operate against the wedges 6i, as shown in Fig. 2, to press the door tightly against the fixed frame 36, compressing the gasket 41 all the way around the door, thus forming a flametight seal. Suitable clearance isprovided in the hinges 39 to permit this. p
Various modifications in form and arrangement of the present device may be made without de- 4 1 parting from the scope oi! this invention as de fined by the appended claims.
The invention described herein may be manu factured and used by r for the Government 0 1; the United States of America for governmenta purposes without the payment of any royaltie. thereon or therefor.
What isolalmed is:
1. In a gunemplacement, an ammunition hols 1Q including, a trunk and a car, a gun loading tray a door hinged at its bottom edge to the trunk am so constructed and arranged as to substantial]: bridge the space between the trunk andlahe loading tray when they door is open, fluid PI'CSSUI'i mechanism arranged to operate the door, sealing means arranged to secure the door to the trunk fluid pressure mechanism arranged to operate the sealing means, and a fluid pressure system including said mechanisms for sequently actuating said mechanisms both to release the sealing means prior to opening the door and to close thr door prior to fastening the sealing means.
2. In a gun emplacement, an ammunition hoist including a trunk and a hoisting car, a gun loading tray, a door hinged at its bottom edge to th! trunk and so constructed and arranged as tc substantially bridge the space between the cal and the loading tray when the door is open; 2 dog coacting with the door to secure the door to the trunk, a dog operating mechanism actuated by a fluid under pressure, a door operating mechanism actuated by a fluid under pres- .sure, and a fluid pressure system including a control valve and said mechanisms arranged to sequentially actuate the dog operating mechanism prior to the door operating mechanism in opening the door and the door operating mechanism prior to the dog operating mechanism inclosing the door.
3. In agun emplacement; an ammunition hoist to hold the door in sealing relation with respect to said port; a fluidjpressure system comprising a dog operating mechanism, a door operating mechanism, means including a control valve for directing a fluid under pressure to first actuate one of said mechanisms, and means including said first actuated mechanism for further direct- ,ing the fluid to thereafter actuatethe other of said mechanisms, whereby the dog operating mechanism releases the dog prior to the operation of the door operating mechanism in opening the door and the door operating mechanism closes the door prior to the operation of the dog operating mechanism in fastening the dog to seal off the said port. 5 4. In a gun emplacement. an ammunition hoist including a trunk and a hoisting car therein with a tiltable tray, a gun loading tray, a door on the trunk with a hinge at the bottom edge of the door located higher than loading tray, the door being so constructed and arranged as to substantially 9 bridge the space between the tiltable tray and the wedge on the outer side of and near an edge of 'aesaoss d the door, a dog pivotaliy attached to the trunk and movable against the wedge to press the gasket against the frame to form a flame tight seal, a dog operating piston and coacting cylinder provided with an outlet which is uncovered by the piston near the end of the dog releasing stroke, a door operating piston and coacting cylinder provided with an outlet which is uncovered by the piston near the end of the door closing stroke, the door operating piston and cylinder serving as a support for the door when open and having a spring counterbalancing the weight of the door, a source of fluid under substantially constant pressure, means including a single manually operable control valve to direct the fluid to one side of the dog operating piston to release the dog, means including the dog operating cylinder outlet to thereafter further direct the fluid to one side of the door operating piston to open the door, means including the control valve to direct the fluid to the opposite side REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 564,474 Cowles July 21, 1896 1,105,813 Meigs et al Aug. 4, 1919 1,371,738 Dawson et'al Mar. 15, 1921 1,392,583 Lee et al Oct. 4, 1921 1,465,990 Lee et al. Aug. 28, 1923 1,849,385 Sekulski Mar. 15, 1932 2,260,080
Lane Oct. 21, 1941
US525964A 1944-03-10 1944-03-10 Door operating mechanism for powder hoists Expired - Lifetime US2452035A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US525964A US2452035A (en) 1944-03-10 1944-03-10 Door operating mechanism for powder hoists

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US525964A US2452035A (en) 1944-03-10 1944-03-10 Door operating mechanism for powder hoists

Publications (1)

Publication Number Publication Date
US2452035A true US2452035A (en) 1948-10-26

Family

ID=24095344

Family Applications (1)

Application Number Title Priority Date Filing Date
US525964A Expired - Lifetime US2452035A (en) 1944-03-10 1944-03-10 Door operating mechanism for powder hoists

Country Status (1)

Country Link
US (1) US2452035A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2750486A (en) * 1953-03-10 1956-06-12 Lombard Corp Door mechanism for induction heating apparatus
US2871361A (en) * 1946-03-28 1959-01-27 Roland E Andrews Calutron assembling and disassembling apparatus
US2871363A (en) * 1946-03-28 1959-01-27 Roland E Andrews Calutron assembling and disassembling apparatus
US3302331A (en) * 1960-07-15 1967-02-07 Sturm Door mechanism
USD368511S (en) 1994-11-04 1996-04-02 Darin Williams Hydraulic power source for shotshell reloader

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US564474A (en) * 1896-07-21 Hydraulic system for closing water-tight bulkheads on board ships
US1105813A (en) * 1914-08-04 Ammunition-hoisting car
US1371738A (en) * 1919-04-09 1921-03-15 Vickers Ltd Gun-mounting
US1392583A (en) * 1920-09-11 1921-10-04 Armstrong Whitworth Co Eng Apparatus for loading ordnance
US1465990A (en) * 1922-11-29 1923-08-28 Armstrong Whitworth Co Eng Ammunition hoist especially suitable for use on board ship
US1849385A (en) * 1928-10-24 1932-03-15 Matthews Conveyer Company Conveying apparatus
US2260080A (en) * 1939-08-14 1941-10-21 Lane Edward Door operating device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US564474A (en) * 1896-07-21 Hydraulic system for closing water-tight bulkheads on board ships
US1105813A (en) * 1914-08-04 Ammunition-hoisting car
US1371738A (en) * 1919-04-09 1921-03-15 Vickers Ltd Gun-mounting
US1392583A (en) * 1920-09-11 1921-10-04 Armstrong Whitworth Co Eng Apparatus for loading ordnance
US1465990A (en) * 1922-11-29 1923-08-28 Armstrong Whitworth Co Eng Ammunition hoist especially suitable for use on board ship
US1849385A (en) * 1928-10-24 1932-03-15 Matthews Conveyer Company Conveying apparatus
US2260080A (en) * 1939-08-14 1941-10-21 Lane Edward Door operating device

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2871361A (en) * 1946-03-28 1959-01-27 Roland E Andrews Calutron assembling and disassembling apparatus
US2871363A (en) * 1946-03-28 1959-01-27 Roland E Andrews Calutron assembling and disassembling apparatus
US2750486A (en) * 1953-03-10 1956-06-12 Lombard Corp Door mechanism for induction heating apparatus
US3302331A (en) * 1960-07-15 1967-02-07 Sturm Door mechanism
USD368511S (en) 1994-11-04 1996-04-02 Darin Williams Hydraulic power source for shotshell reloader

Similar Documents

Publication Publication Date Title
US2595248A (en) Hydraulic system for poweroperated hatch covers
US2452035A (en) Door operating mechanism for powder hoists
CN109179283A (en) Well lid overturning mechanism for opening/closing and its fluid power system based on Four-connecting-rod hinge
US4858981A (en) Vehicle loading attachment
US1966378A (en) Mechanism for operating baling presses
US2217283A (en) Hydraulic dump bucket
US1944351A (en) Hoist mechanism
US3615028A (en) Refuse handling apparatus
GB1303342A (en)
US5518129A (en) Boom including plural arms telescopically extendible and retractable successively
US3164959A (en) Hydraulic systems
US1807231A (en) Elevator door operating mechanism
US2743704A (en) Automatic stop for fluid motor
US2143546A (en) Hydraulic hoisting system and control with apparatus therefor
US2813641A (en) Auxiliary compressing panel for refuse trucks
US2491261A (en) Power operated hatch cover
US3061128A (en) Skip with hydraulically operated dumping door
US2558867A (en) Door operating mechanism
KR19990063756A (en) Linear Preload Hydraulically Actuated Latches
US2351317A (en) Hydraulic press system
US2438924A (en) Muzzle closure device for guns
USRE24238E (en) Power operated hatch cover
US2490797A (en) Hoisting apparatus
US2101067A (en) Material handling apparatus
GB1037549A (en) Hydraulic door opener