US2754018A - Hydraulic power lines for industrial truck - Google Patents
Hydraulic power lines for industrial truck Download PDFInfo
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- US2754018A US2754018A US367508A US36750853A US2754018A US 2754018 A US2754018 A US 2754018A US 367508 A US367508 A US 367508A US 36750853 A US36750853 A US 36750853A US 2754018 A US2754018 A US 2754018A
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- Prior art keywords
- carriage
- hydraulic
- main frame
- fluid
- valve
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Classifications
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- 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
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/12—Platforms; Forks; Other load supporting or gripping members
- B66F9/18—Load gripping or retaining means
- B66F9/184—Roll clamps
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/20—Means for actuating or controlling masts, platforms, or forks
- B66F9/22—Hydraulic devices or systems
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- 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
- F15B2211/30585—Assemblies of multiple valves having a single valve for multiple output members
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- 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
- F15B2211/3059—Assemblies of multiple valves having multiple valves for multiple output members
- F15B2211/30595—Assemblies of multiple valves having multiple valves for multiple output members with additional valves between the groups of valves for multiple output members
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- 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
- F15B2211/327—Directional 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
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
- F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups
Definitions
- This invention relates to industrial lift trucks. More particularly, my invention relates to hydraulic means for operating load manipulating devices on the lifting carriage of trucks of this class.
- I direct the fluid pressure through a flexible line to the lifting, carriage, with valve means at the carriage then directing the pressure to the rams individually in accordance with the positioning of the valve'means.
- I utilize but a single manually operated valve on the truck to control several load manipulating devices on the carriage.
- the rams or motors are of the type that discharges exhaust fluid while being actuated by the fluid under pressure
- I utilize a pair of the flexible lines extending between the truck and the carriage, with the manually operated valve allowing the fluid to return through one of these lines to the source on the truck while the fluid pressure is applied through the other line.
- the rams are of the type that discharge fluid only when moving in a reverse direction, it is not necessary to provide for fluid flow simultaneously both directions between the truck and carriage, and I can utilize merely a single flexible line. In no case, however; do I require more than a pair of. flexible hydraulic lin'e's', because my invention enables me to direct fluid inb'o'th directions between the flexible lines and the individual rants or motors.
- I provide means upon the main frame of the truck for actuating the valve means on the carriage.
- the operator can very easily control the individual load manipulating devices. More particularly, I prefer to utilize solenoids for positioning the valve means, with switch means upon the truck for actuating the solenoids.
- Fig. 1 is a side view of a lift truck vention.
- Fig. 2 is a plan view of the truck.
- Fig. 3 is a diagram illustrating my novel power line arrangement.
- FIGs. 1 and 2 For the purpose of describing my invention, I show in Figs. 1 and 2 several load manipulating devices mounted upon a lifting carriage III that moves vertically on uprights 11 of an industrial truck T.
- the particular details of the truck T are not important to an understanding of my invention, and it is merely necessary to know that the carriage 10 moves relatively to the truck.
- one of the load manipulating devices as a load clamping means having clamping arms 12, 13' on a base member 14.
- the arm 13 is mounted on the base member 14 through apivot 15 for movement relatively to the arm 12, and a hydraulic ram 16 at the rear end of the arm 13 is adapted to move this arm in opposed directions on its pivot 15 for clamping and releasing a load between the arms.
- the base member 14 is mounted to rotate on the longitudinal axis of the truck, relatively to a member I7 on't-he carriage 10. This rotation is effected through ahydraulic motor' or ram 18 on the member 17, and thereby a load clamped betweenthe arms 12, 13 can be inverted or tilted to a desired angle.
- I show a hydraulic ram 19 on the carriage 10 that is adapted to shift the member 17 in a transverse direction relatively to the truck.
- the clamping arms 12, 13 can be shifted in a sidewise direction to be brought into proper alignment with a load to be picked up, or to shift a load already clamped between the aruis.
- Extending between the main frame of the truck T and the lifting carriage 10 I provide a pair of flexible hydraulic lines 20, 21 that are shown in Figs; 1 and 2-, but best seen in their relation to the hydraulic system in- Fig. 3.
- the hydraulic lines 20, 21 are connected to a manually operated valve 22, and this valve is connected in turn to a source of fluid pressure S through a supply line 23" and a return line 24;
- the manually operated valve 22 has passages 25* whereby the supply and return lines 235, 24 can be placed in communication with the flexible lines 20', 21,
- the supply line 23 is connected by a passage 25 with the flexible line 21 whereby the line 21 also is a supply line, and the flexible line 20 is a return line because it is connected through the other passage 25 with the return line 24.
- the flexible line 20 is a supply line, while the line 21 is a return line.
- the valve 22 may, of course, be rotated to an intermediate holding position in which the passages 25 do not connect any of the hydraulic lines.
- valve 26 having a piston 27, and a second similar valve 28 having a piston 29.
- the piston 27 of the first valve 26 has two peripheral recesses 30, 31, and each flexible line 20, 21 is in communication with one of these recesses at all times.
- a pair of lines or passages 32, 33 that lead to the second valve 28, thereby transmitting to the second valve fluid pressure from one of the flexible lines 20, 21, and also returning fluid from the valve 28 to the other flexible line 20 or 21.
- fluid pressure from the supply line 23 can be applied to either end of the rotating ram 18, depending upon the position of the manually operated valve 22, with the fluid discharged from the opposed end of the ram moving simultaneously to the return line 24.
- the piston 29 has peripheral recesses 36, 37 that normally place the passages 32, 33 in communication with lines 38, 39 leading to opposed ends of the clamp ram 16.
- I utilize the second valve 28 also to direct fluid relatively to the shift ram 19, and for this purpose I provide hydraulic lines 40, 41 between the valve 28 and opposed ends of the ram 19.
- the arrangement is such that, when the valve 28 is actuated, the piston 29 cuts olf communication between the passages 32, 33 and the lines 38, 39, and the recesses 36, 37 in the piston place the passages 32, 33 in communication with the lines 40, 41. Therefore, when the second valve 28 is actuated and the first valve 26 is not actuated, the shift ram 19 can be operated in either direction under the full control of the manually operated valve 22.
- valves 26, 28 are of the type having a spring 42 pressing the piston to a normal position, with a solenoid 43 that when energized moves the piston to actuated position.
- I mount suitable switch means that I show by way of example as a pair of push button switches 44, 45.
- the switch 44 is connected to a battery 46 on the truck by a wire 47, and when pressed places the solenoid 43 of the first valve 26 in circuit with the battery through wires 48, 49.
- the push button 45 is adapted to place the solenoid of the second valve 28 in circuit with the battery 46 through the wire 47 and wires 50 and 51, the wire 51 being connected to the battery 46 through the wire 49.
- the wires 48, 49, and 50 are parts of a cable that extends between the main frame of the truck T and the lifting carriage 10, as will be understood by those skilled in the art.
- valves 26 and 28 are in their unactuated positions as shown in Fig. 3, with the flexible lines 20, 21 in communication through these valves with the lines 38, 39, so that the clamp ram 16 can be operated merely through movement of the manually operated valve 22. Therefore, if the truck T is maneuvered to bring the clamping arms 12, 13, into position at opposed sides of a load to be lifted, movement of the valve 22 will effect clamping of the load, and will release the load without requiring any additional control operation.
- valve 26 If we assume now that it is desired to rotate the load clamped between the arms 12, 13 after it has been lifted on the carriage 10, the operator will first press the push button 44. This action will actuate the valve 26, thereby cutting off communication between the flexible lines 20, 21 and the second valve 28, and placing these lines in communication with the rotating ram or motor 18 through the lines 34, 35. If the operator now manipulates the valve 22 on the truck while holding the push button 44 depressed, the fluid pressure will be directed to the ram or motor 18 to rotate the load with the direction of rotation determined by valve 22.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines on the carriage in communication with said hydraulic motors, selector valve means on said carriage between the flexible hydraulic lines and said lines on the carriage, and means on said main frame for actuating the selector valve means whereby to direct the fluid to and from each of the motors for said load manipulating devices individually.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main farme, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines. onthe. carriage in communication with said. hydraulic motors, selector valve means on: the lifting carriage between the. flexible hydraulic lines and the lines on the carriage,.means.for positioning the selector valve means whereby to direct the fluid to and from each of the hydraulic motors individually, and a. manually operated valve on said main frame controlling the flow of fluid in opposed directions in said flexible hydraulic lines whereby to operate particular load manipulating devices in accordance with the positioning of said selector valve means.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions .of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines on the carriage in communication with said hydraulic motors, selector valve means on said carriage between the flexible hydraulic lines and said lines on the carriage, electrical means on the lifting carriage for positioning said selector valve means whereby to direct the fluid to a particular hydraulic motor individually, and means on the main frame for actuating said electrical means.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, a plurality of load manipulating devices on said lifting carriage, a hydraulic ram on said carriage for each of said load manipulating devices, a source of fluid pressure on said main frame, a pair of hydraulic lines extending between said source and said carriage for carrying fluid under pressure to said carriage and back to said source, a manually operated valve on said main frame for controlling the direction of the flow of fluid in said pair of hydraulic lines, valve means on the carriage in communication with said pair of hydraulic lines, carriage supported hydraulic lines in communication with said valve means on said carriage to form a fluid circuit for the supply and return of fluid to each of said rams, and means positioning said valve means on said carriage in predetermined relation to said manually operated valve to direct with said manually operated valve the fluid relatively to each of said rams whereby to operate selected corresponding load manipulating devices in opposed directions.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, a plurality of load manipulating devices on said lifting carriage, a hydraulic ram on said carriage for each of said load manipulating devices, a source of fluid pressure on said main frame, a pair of hydraulic lines extending between said source and said carriage for carrying fluid under pressure to said carriage and back to said source, a manually operated valve on said main frame for controlling the direction of the flow of fluid in said pair of hydraulic lines, valve means on the carriage in communication with said pair of hydraulic lines, carriage supported hydraulic lines in communication with said valve means on said carriage to form a fluid circuit for the supply and return of fluid to each of said rams, solenoid means on said carriage for positioning said valve means to direct the fluid relatively to each of said rams, and switch means on said main frame for actuating said solenoid means to effect with said manually operated valve the individual operation of selected load manipulating devices.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating device'sv on saidliftihg carriage, a hydraulic rant on said: carriage for each of said load: manipulating devices, a source of fluid pressure on said main: frame, a pair of hydraulic lines extending between said source and said carriage.
- valve means on the carriage in communication with said pair of hydraulic lines and with each of said rams, manual means on said main frame of the truck for directing the flow of fluid in opposed directions in said hydraulic lines, and means on said main frame for actuating said valve means in combination with said manual means to direct the fluid pressure to one side or the other of each of said rams whereby to control the operation of said load manipulating devices.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor on said lifting carriage for each of said load manipulating devices, hydraulic valve means on said carriage for controlling each of said hydraulic motors, a source of hydraulic pressure on said main frame, a flexible hydraulic line in communication with said source on the main frame and extending from said main frame to said valve means on the carriage for supplying fluid through said valve means to all of said hydraulic motors in all vertical positions to which the load manipulating devices move with the carriage, and additional means on said main frame extending to said valve means on said carriage for positioning said valve means whereby to direct the fluid from the flexible hydraulic line to one or another of said motors for operating said load manipulating devices individually.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor on said lifting carriage for each of said load manipulating devices, selector valve means on said carriage, hydraulic lines through which said valve means are in communication with said hydraulic motors on the carriage, a source of hydraulic pressure on said main frame, a flexible hydraulic line in communication with said source on the main frame and extending to the selector valve means on the carriage for supplying fluid through said valve means and lines to all of said hydraulic motors in all vertical positions to which the load manipulating devices move with the carriage, additional means on said main frame extending to the selector valve means on the carriage for positioning said valve means to direct the fluid from the flexible hydraulic line to one or another of said motors, and a manually operated valve on the main frame controlling the flow of fluid in said flexible hydraulic line whereby to operate individually the load manipulating devices on the carriage in accordance with the positioning of said selector valve means.
- an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic ram on said lifting carriage for each of said load manipulating devices, selector valve means on said carriage, hydraulic lines through which said selector valve means are in communication with each of said hydraulic rams, a source of hydraulic pressure on said main frame, a flexible hydraulic line extending from the main frame to the selector valve means on the carriage for supplying fluid from said source to all of said hydraulic rams in all vertical positions to which the load manipulating devices move with the carriage, electrical means on the carriage for positioning said selector valve means to direct the fluid through the lines on the carriage to the hydraulic rams individually, switch means on the main frame for actuating said electrical means, and a manually operated valve on the main frame controlling the flow of fluid in References Cited in the file of this patent UNITED STATES PATENTS Foster Feb. 7 1939 8 Twyman June 24, 1941 Jeffrey Nov. 23, 1943 Fitch July 31,
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Description
July 10, 1956 c. s. SCHROEDER 2,7
HYDRAULIC POWER LINES FOR INDUSTRIAL TRUCK Filed July 13, 1953 2 Sheets-Sheet 1 hl h 2 I 1 l as 6 INVENTCR BYMM ATTORNEY July 10, 1956 c s, SCHRQEDER 2,754,018
HYDRAULIC POWER LINES FOR INDUSTRIAL TRUCK Filed July 13, 1953 2 Sheets-Sheet 2 fla -J.
2 i 45 34 25 I: I I I I 47 I I I I I I I I Z] 46 I T I no I L OE C A'I;FEI A G E i I I I 50 51 37 I I I I l I Z I I 49 E ROTATING 42 "/mslglgl l 2s 4 I I I I I I 5 I I I I I I I I I I I I I I I I I ATTORNEY United States Patent HYDRAULIC PGWER LINES FOR INDUSTRIAL TRUCK Charles S. Schroeder, Philadelphia, Pa., assignor to The Yale & Towns Manufacturing Company, Stamford, Conn, a corporation of Connecticut Application July 13, 1953, Serial No. 367,508
9 Claims. (Cl. 214-652) This invention relates to industrial lift trucks. More particularly, my invention relates to hydraulic means for operating load manipulating devices on the lifting carriage of trucks of this class.
It is quite usual to provide upon the lifting carriage, in trucks of this class, a hydraulic motor or ram for operating a load manipulating device, with the motor or ram powered by a source of fluid pressure on the main frame of the truck. To convey the fluid pressure to the ram in all vertical positions of the carriage relatively to the truck, flexible hydraulic lines extend from the main frame to the carriage. A manually operated valve on the truck controls the fluid in the hydraulic lines, and thereby enables the operator to control the load manipulating device.
It is frequently desired to utilize two or more load manipulating devices on the lifting carriage. At least one motor or ram is required for operating each load manipulating device, and, to enable the operator to have individual control over all of these motors or rams, the prior art utilizes separate flexible lines extending from the main frame to the carriage for each ram or motor. Obviously, this means that for a fairly complex series of load manipulating devices, the prior art requires a complex array of flexible hose.
I have now contributed by my invention an extremely novel hydraulic system through which I provide complete and individual control over the individual rams or motors for several load manipulating devices while utilizing. only the same number of flexible hydraulic lines required for operating one motor or ram.
As one important feature of my invention, I direct the fluid pressure through a flexible line to the lifting, carriage, with valve means at the carriage then directing the pressure to the rams individually in accordance with the positioning of the valve'means. Preferably, with this arrangement I utilize but a single manually operated valve on the truck to control several load manipulating devices on the carriage. When the rams or motors are of the type that discharges exhaust fluid while being actuated by the fluid under pressure, I utilize a pair of the flexible lines extending between the truck and the carriage, with the manually operated valve allowing the fluid to return through one of these lines to the source on the truck while the fluid pressure is applied through the other line. If the rams are of the type that discharge fluid only when moving in a reverse direction, it is not necessary to provide for fluid flow simultaneously both directions between the truck and carriage, and I can utilize merely a single flexible line. In no case, however; do I require more than a pair of. flexible hydraulic lin'e's', because my invention enables me to direct fluid inb'o'th directions between the flexible lines and the individual rants or motors.
As more detailed feature of my invention, I provide means upon the main frame of the truck for actuating the valve means on the carriage. Through this arrangement, in conjunction with a manually operated valve: on the truck, the operator can very easily control the individual load manipulating devices. More particularly, I prefer to utilize solenoids for positioning the valve means, with switch means upon the truck for actuating the solenoids.
I have thus outlined rather broadly the more important features of my invention in order that the detailed description thereof that follows may be better understood, and in order that my c'on'tribution'to the art may be better appreciated. There are, of course, additional features of my invention that will be described hereinafter and which will form the subject of the claims appended hereto. Those skilled in the art will appreciate that the conception on which my disclosure is based may readily be utilized as a basis for the designingof other structures for carrying out the several purposes of my invention. It is important, therefore, that the claims be regarded as including such equivalent constructions as do not depart from the spirit and scope of my invention, in order to prevent the appropriation of my invention by those skilled in the art.
Referring now to the drawings:
Fig. 1 is a side view of a lift truck vention.
Fig. 2 is a plan view of the truck.
Fig. 3 is a diagram illustrating my novel power line arrangement. a
For the purpose of describing my invention, I show in Figs. 1 and 2 several load manipulating devices mounted upon a lifting carriage III that moves vertically on uprights 11 of an industrial truck T. The particular details of the truck T are not important to an understanding of my invention, and it is merely necessary to know that the carriage 10 moves relatively to the truck.
By way of example, I have illustrated one of the load manipulating devices as a load clamping means having clamping arms 12, 13' on a base member 14. The arm 13 is mounted on the base member 14 through apivot 15 for movement relatively to the arm 12, and a hydraulic ram 16 at the rear end of the arm 13 is adapted to move this arm in opposed directions on its pivot 15 for clamping and releasing a load between the arms.
As an example of a further manipulating device, the base member 14 is mounted to rotate on the longitudinal axis of the truck, relatively to a member I7 on't-he carriage 10. This rotation is effected through ahydraulic motor' or ram 18 on the member 17, and thereby a load clamped betweenthe arms 12, 13 can be inverted or tilted to a desired angle.
Still further, I show a hydraulic ram 19 on the carriage 10 that is adapted to shift the member 17 in a transverse direction relatively to the truck. Through this arrangement, the clamping arms 12, 13 can be shifted in a sidewise direction to be brought into proper alignment with a load to be picked up, or to shift a load already clamped between the aruis.
The load manipulating devices as I have described them are conventional, and it will be understood that my invention is not limited to any particular manipulating devices. My invention is directed rather toward the novel hydraulic system whereby I operate the load manipulating devices, and I shall now proceed to describe this hydraulic system.
Extending between the main frame of the truck T and the lifting carriage 10 I provide a pair of flexible hydraulic lines 20, 21 that are shown in Figs; 1 and 2-, but best seen in their relation to the hydraulic system in- Fig. 3. Upon the main frame of the truck, the hydraulic lines 20, 21 are connected to a manually operated valve 22, and this valve is connected in turn to a source of fluid pressure S through a supply line 23" and a return line 24; The manually operated valve 22 has passages 25* whereby the supply and return lines 235, 24 can be placed in communication with the flexible lines 20', 21,
embodying my in- 3 with rotation of the valve reversing the relation between the lines. Thus, in the position of the valve shown in Fig. 3, the supply line 23 is connected by a passage 25 with the flexible line 21 whereby the line 21 also is a supply line, and the flexible line 20 is a return line because it is connected through the other passage 25 with the return line 24. When the passages 25 are placed in their dotted line positions by rotation of the valve 22, the flexible line 20 is a supply line, while the line 21 is a return line. The valve 22 may, of course, be rotated to an intermediate holding position in which the passages 25 do not connect any of the hydraulic lines.
To serve as the valve means upon the lifting carriage, I prefer to utilize a valve 26 having a piston 27, and a second similar valve 28 having a piston 29. The piston 27 of the first valve 26 has two peripheral recesses 30, 31, and each flexible line 20, 21 is in communication with one of these recesses at all times. Also in communication with the recesses 30, 31, in the normal position of the piston 27 are a pair of lines or passages 32, 33 that lead to the second valve 28, thereby transmitting to the second valve fluid pressure from one of the flexible lines 20, 21, and also returning fluid from the valve 28 to the other flexible line 20 or 21., I shall describe fully the action of the valve 28, but it is first to be noted that, when the valve 26 is actuated, the piston 27 moves in such a way as to cut off communication between the flexible lines 20, 21 and the passages 32, 33, with the recesses 30, 31 then placing the lines 20, 21 in communication with lines 34, 35 that lead to opposed ends of the rotating ram 18. Upon actuation of the valves 26, therefore, fluid pressure from the supply line 23 can be applied to either end of the rotating ram 18, depending upon the position of the manually operated valve 22, with the fluid discharged from the opposed end of the ram moving simultaneously to the return line 24.
Returning now to the second valve 28, it will be observed that the piston 29 has peripheral recesses 36, 37 that normally place the passages 32, 33 in communication with lines 38, 39 leading to opposed ends of the clamp ram 16. By this arrangement, when the valves 26 and 28 are both in normal position, the fluid pressure is applied to either end of the clamp ram 16 through manipulation of the manually operated valve 22, while the fluid discharged from the opposed end of the ram returns to the line 24.
I utilize the second valve 28 also to direct fluid relatively to the shift ram 19, and for this purpose I provide hydraulic lines 40, 41 between the valve 28 and opposed ends of the ram 19. The arrangement is such that, when the valve 28 is actuated, the piston 29 cuts olf communication between the passages 32, 33 and the lines 38, 39, and the recesses 36, 37 in the piston place the passages 32, 33 in communication with the lines 40, 41. Therefore, when the second valve 28 is actuated and the first valve 26 is not actuated, the shift ram 19 can be operated in either direction under the full control of the manually operated valve 22.
I have not thus far described a particular means for actuating the valves 26 and 28 on the lifting carriage, but I do prefer to utilize electrical means for this purpose. Thus, the valves 26, 28 are of the type having a spring 42 pressing the piston to a normal position, with a solenoid 43 that when energized moves the piston to actuated position. Upon the main frame of the truck T, in a position convenient to the operator, I mount suitable switch means that I show by way of example as a pair of push button switches 44, 45. The switch 44 is connected to a battery 46 on the truck by a wire 47, and when pressed places the solenoid 43 of the first valve 26 in circuit with the battery through wires 48, 49. The push button 45 is adapted to place the solenoid of the second valve 28 in circuit with the battery 46 through the wire 47 and wires 50 and 51, the wire 51 being connected to the battery 46 through the wire 49. Preferably, the wires 48, 49, and 50 are parts of a cable that extends between the main frame of the truck T and the lifting carriage 10, as will be understood by those skilled in the art.
It may be well to review now the operation of my extremely novel hydraulic system. Normally the valves 26 and 28 are in their unactuated positions as shown in Fig. 3, with the flexible lines 20, 21 in communication through these valves with the lines 38, 39, so that the clamp ram 16 can be operated merely through movement of the manually operated valve 22. Therefore, if the truck T is maneuvered to bring the clamping arms 12, 13, into position at opposed sides of a load to be lifted, movement of the valve 22 will effect clamping of the load, and will release the load without requiring any additional control operation.
If we assume now that it is desired to rotate the load clamped between the arms 12, 13 after it has been lifted on the carriage 10, the operator will first press the push button 44. This action will actuate the valve 26, thereby cutting off communication between the flexible lines 20, 21 and the second valve 28, and placing these lines in communication with the rotating ram or motor 18 through the lines 34, 35. If the operator now manipulates the valve 22 on the truck while holding the push button 44 depressed, the fluid pressure will be directed to the ram or motor 18 to rotate the load with the direction of rotation determined by valve 22.
In those circumstances in which it is desired to shift the clamping arms 12, 13 transversely, first the push button 45 will be depressed While leaving the push button 44 in normal position, thereby actuating only the second valve 28. The flexible lines 20, 21 are now in communication with the second valve 28, and through this valve with the shift ram 19. The operator will now manipulate the valve 22 to direct the fluid pressure to either end of the ram 19, thus shifting the arms 12, 13 sidcwise in either direction.
I believe that those skilled in the art will now understand the extremely novel construction whereby I utilize one pair of hydraulic lines to accomplish the individual operation of several load manipulating devices on the lift ing carriage of an industrial truck, and that the very considerable value of my contribution will be fully appreciated.
I now claim:
1. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines on the carriage in communication with said hydraulic motors, selector valve means on said carriage between the flexible hydraulic lines and said lines on the carriage, and means on said main frame for actuating the selector valve means whereby to direct the fluid to and from each of the motors for said load manipulating devices individually.
2. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main farme, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines. onthe. carriage in communication with said. hydraulic motors, selector valve means on: the lifting carriage between the. flexible hydraulic lines and the lines on the carriage,.means.for positioning the selector valve means whereby to direct the fluid to and from each of the hydraulic motors individually, and a. manually operated valve on said main frame controlling the flow of fluid in opposed directions in said flexible hydraulic lines whereby to operate particular load manipulating devices in accordance with the positioning of said selector valve means.
3. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor for each of said load manipulating devices, a source of fluid pressure on said main frame, a flexible hydraulic line through which fluid flows between said fluid source and said carriage in all vertical positions .of the carriage relatively to the main frame, a second flexible hydraulic line through which fluid flows from said carriage in all vertical positions thereof back to said fluid source, hydraulic lines on the carriage in communication with said hydraulic motors, selector valve means on said carriage between the flexible hydraulic lines and said lines on the carriage, electrical means on the lifting carriage for positioning said selector valve means whereby to direct the fluid to a particular hydraulic motor individually, and means on the main frame for actuating said electrical means.
4. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, a plurality of load manipulating devices on said lifting carriage, a hydraulic ram on said carriage for each of said load manipulating devices, a source of fluid pressure on said main frame, a pair of hydraulic lines extending between said source and said carriage for carrying fluid under pressure to said carriage and back to said source, a manually operated valve on said main frame for controlling the direction of the flow of fluid in said pair of hydraulic lines, valve means on the carriage in communication with said pair of hydraulic lines, carriage supported hydraulic lines in communication with said valve means on said carriage to form a fluid circuit for the supply and return of fluid to each of said rams, and means positioning said valve means on said carriage in predetermined relation to said manually operated valve to direct with said manually operated valve the fluid relatively to each of said rams whereby to operate selected corresponding load manipulating devices in opposed directions.
5. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, a plurality of load manipulating devices on said lifting carriage, a hydraulic ram on said carriage for each of said load manipulating devices, a source of fluid pressure on said main frame, a pair of hydraulic lines extending between said source and said carriage for carrying fluid under pressure to said carriage and back to said source, a manually operated valve on said main frame for controlling the direction of the flow of fluid in said pair of hydraulic lines, valve means on the carriage in communication with said pair of hydraulic lines, carriage supported hydraulic lines in communication with said valve means on said carriage to form a fluid circuit for the supply and return of fluid to each of said rams, solenoid means on said carriage for positioning said valve means to direct the fluid relatively to each of said rams, and switch means on said main frame for actuating said solenoid means to effect with said manually operated valve the individual operation of selected load manipulating devices.
6. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating device'sv on saidliftihg carriage, a hydraulic rant on said: carriage for each of said load: manipulating devices, a source of fluid pressure on said main: frame, a pair of hydraulic lines extending between said source and said carriage. for carrying fluid-under pressure to said carriage and back to said; source; in one direction or the other, valve means on the carriage in communication with said pair of hydraulic lines and with each of said rams, manual means on said main frame of the truck for directing the flow of fluid in opposed directions in said hydraulic lines, and means on said main frame for actuating said valve means in combination with said manual means to direct the fluid pressure to one side or the other of each of said rams whereby to control the operation of said load manipulating devices.
7. ln a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor on said lifting carriage for each of said load manipulating devices, hydraulic valve means on said carriage for controlling each of said hydraulic motors, a source of hydraulic pressure on said main frame, a flexible hydraulic line in communication with said source on the main frame and extending from said main frame to said valve means on the carriage for supplying fluid through said valve means to all of said hydraulic motors in all vertical positions to which the load manipulating devices move with the carriage, and additional means on said main frame extending to said valve means on said carriage for positioning said valve means whereby to direct the fluid from the flexible hydraulic line to one or another of said motors for operating said load manipulating devices individually.
8. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic motor on said lifting carriage for each of said load manipulating devices, selector valve means on said carriage, hydraulic lines through which said valve means are in communication with said hydraulic motors on the carriage, a source of hydraulic pressure on said main frame, a flexible hydraulic line in communication with said source on the main frame and extending to the selector valve means on the carriage for supplying fluid through said valve means and lines to all of said hydraulic motors in all vertical positions to which the load manipulating devices move with the carriage, additional means on said main frame extending to the selector valve means on the carriage for positioning said valve means to direct the fluid from the flexible hydraulic line to one or another of said motors, and a manually operated valve on the main frame controlling the flow of fluid in said flexible hydraulic line whereby to operate individually the load manipulating devices on the carriage in accordance with the positioning of said selector valve means.
9. In a combination of the class described, an industrial truck having a main frame, a lifting carriage moving vertically on said main frame, at least two load manipulating devices on said lifting carriage, a separate hydraulic ram on said lifting carriage for each of said load manipulating devices, selector valve means on said carriage, hydraulic lines through which said selector valve means are in communication with each of said hydraulic rams, a source of hydraulic pressure on said main frame, a flexible hydraulic line extending from the main frame to the selector valve means on the carriage for supplying fluid from said source to all of said hydraulic rams in all vertical positions to which the load manipulating devices move with the carriage, electrical means on the carriage for positioning said selector valve means to direct the fluid through the lines on the carriage to the hydraulic rams individually, switch means on the main frame for actuating said electrical means, and a manually operated valve on the main frame controlling the flow of fluid in References Cited in the file of this patent UNITED STATES PATENTS Foster Feb. 7 1939 8 Twyman June 24, 1941 Jeffrey Nov. 23, 1943 Fitch July 31, 1945 Glenn Nov. 20, 1951 Turner June 3, 1952 Sherrifi Aug. 4, 1953
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US367508A US2754018A (en) | 1953-07-13 | 1953-07-13 | Hydraulic power lines for industrial truck |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US367508A US2754018A (en) | 1953-07-13 | 1953-07-13 | Hydraulic power lines for industrial truck |
Publications (1)
Publication Number | Publication Date |
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US2754018A true US2754018A (en) | 1956-07-10 |
Family
ID=23447466
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US367508A Expired - Lifetime US2754018A (en) | 1953-07-13 | 1953-07-13 | Hydraulic power lines for industrial truck |
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US (1) | US2754018A (en) |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2821317A (en) * | 1956-02-06 | 1958-01-28 | Burton H Locke | Materials clamping devices for lift trucks |
US2821377A (en) * | 1956-04-04 | 1958-01-28 | Pennsylvania Engineering Corp | Vessel charging apparatus |
US2920775A (en) * | 1956-05-09 | 1960-01-12 | Otis Elevator Co | Load clamps for an industrial truck |
US2932419A (en) * | 1957-01-18 | 1960-04-12 | Hyster Co | Hose control arrangement |
DE1144553B (en) * | 1960-02-04 | 1963-02-28 | Yale & Towne Mfg Co | Valve arrangement |
DE1157544B (en) * | 1957-01-28 | 1963-11-14 | Yale & Towne Mfg Co | Loader with telescopic mast |
DE1174262B (en) * | 1958-04-28 | 1964-07-16 | Clark Equipment Co | A lift truck with an extendable and tiltable mast |
US3166207A (en) * | 1961-03-02 | 1965-01-19 | Yale & Towne Inc | Control for load side shifting |
US3179274A (en) * | 1962-09-28 | 1965-04-20 | Allis Chalmers Mfg Co | Control system for lift truck attachment |
US3180514A (en) * | 1963-03-14 | 1965-04-27 | Yale & Towne Inc | Control system for a load handling attachment on an industrial truck |
DE1264334B (en) * | 1963-03-14 | 1968-03-21 | Eaton Yale & Towne | Loader with control for several hydraulic drives on the lifting carriage |
US3623620A (en) * | 1969-11-04 | 1971-11-30 | Howard H Vermette | Device for elevating as well as tipping or tilting drums, barrels, containers, and the like |
US4177000A (en) * | 1978-03-22 | 1979-12-04 | Cascade Corporation | Rotatable load clamp adapted for selective load positioning in response to selective rotational positioning of clamp |
US4215622A (en) * | 1978-09-22 | 1980-08-05 | Clark Equipment Company | Hydraulic control system |
EP0099355A1 (en) * | 1982-01-13 | 1984-02-01 | Towmotor Corp | Container handler with programmed electro-hydraulic control circuit. |
US5281076A (en) * | 1991-05-08 | 1994-01-25 | Liberty Diversified Industries | Forklift attachment |
US5927932A (en) * | 1997-10-24 | 1999-07-27 | Cascade Corporation | Clamp assembly with automatic rotation control |
EP1589232A3 (en) * | 2004-04-23 | 2006-03-29 | Botschafter-Knopff, IIse | Hydraulic control device |
EP1663842A2 (en) * | 2003-09-24 | 2006-06-07 | Cascade Corporation | Hydraulically-synchronized clamp for handling stacked loads of different sizes |
US8568079B2 (en) | 2012-02-15 | 2013-10-29 | Cascade Corporation | Rotator braking system for a lift truck load handler |
CN104555464A (en) * | 2014-12-28 | 2015-04-29 | 临颍县颍机机械制造有限公司 | High-lift four-drive agricultural embracing type grass gripping machine |
ITUB20160750A1 (en) * | 2016-02-15 | 2017-08-15 | Atlantic Fluid Tech S R L | Pilot operated flow diverter valve |
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US2145977A (en) * | 1936-06-11 | 1939-02-07 | Kingsbury Machine Tool Corp | Solenoid actuated valve |
US2247141A (en) * | 1938-04-15 | 1941-06-24 | Vickers Inc | Multiple valve bank |
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US2647650A (en) * | 1950-03-01 | 1953-08-04 | Clark Equipment Co | Combination clamp and rotating mechanism |
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US2334770A (en) * | 1934-07-06 | 1943-11-23 | Jeffrey Mfg Co | Mining machine |
US2145977A (en) * | 1936-06-11 | 1939-02-07 | Kingsbury Machine Tool Corp | Solenoid actuated valve |
US2247141A (en) * | 1938-04-15 | 1941-06-24 | Vickers Inc | Multiple valve bank |
US2380510A (en) * | 1942-10-12 | 1945-07-31 | Aro Equipment Corp | Servo unit |
US2598865A (en) * | 1948-10-05 | 1952-06-03 | Clark Equipment Co | Industrial truck |
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Cited By (26)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2821317A (en) * | 1956-02-06 | 1958-01-28 | Burton H Locke | Materials clamping devices for lift trucks |
US2821377A (en) * | 1956-04-04 | 1958-01-28 | Pennsylvania Engineering Corp | Vessel charging apparatus |
US2920775A (en) * | 1956-05-09 | 1960-01-12 | Otis Elevator Co | Load clamps for an industrial truck |
US2932419A (en) * | 1957-01-18 | 1960-04-12 | Hyster Co | Hose control arrangement |
DE1157544B (en) * | 1957-01-28 | 1963-11-14 | Yale & Towne Mfg Co | Loader with telescopic mast |
DE1174262B (en) * | 1958-04-28 | 1964-07-16 | Clark Equipment Co | A lift truck with an extendable and tiltable mast |
DE1144553B (en) * | 1960-02-04 | 1963-02-28 | Yale & Towne Mfg Co | Valve arrangement |
US3166207A (en) * | 1961-03-02 | 1965-01-19 | Yale & Towne Inc | Control for load side shifting |
US3179274A (en) * | 1962-09-28 | 1965-04-20 | Allis Chalmers Mfg Co | Control system for lift truck attachment |
US3180514A (en) * | 1963-03-14 | 1965-04-27 | Yale & Towne Inc | Control system for a load handling attachment on an industrial truck |
DE1264334B (en) * | 1963-03-14 | 1968-03-21 | Eaton Yale & Towne | Loader with control for several hydraulic drives on the lifting carriage |
US3623620A (en) * | 1969-11-04 | 1971-11-30 | Howard H Vermette | Device for elevating as well as tipping or tilting drums, barrels, containers, and the like |
US4177000A (en) * | 1978-03-22 | 1979-12-04 | Cascade Corporation | Rotatable load clamp adapted for selective load positioning in response to selective rotational positioning of clamp |
US4215622A (en) * | 1978-09-22 | 1980-08-05 | Clark Equipment Company | Hydraulic control system |
EP0099355A1 (en) * | 1982-01-13 | 1984-02-01 | Towmotor Corp | Container handler with programmed electro-hydraulic control circuit. |
EP0099355A4 (en) * | 1982-01-13 | 1984-05-29 | Towmotor Corp | Container handler with programmed electro-hydraulic control circuit. |
US4523886A (en) * | 1982-01-13 | 1985-06-18 | Towmotor Corporation | Container handler with programmed electro-hydraulic control circuit |
US5281076A (en) * | 1991-05-08 | 1994-01-25 | Liberty Diversified Industries | Forklift attachment |
US5927932A (en) * | 1997-10-24 | 1999-07-27 | Cascade Corporation | Clamp assembly with automatic rotation control |
EP1663842A4 (en) * | 2003-09-24 | 2008-05-14 | Cascade Corp | Hydraulically-synchronized clamp for handling stacked loads of different sizes |
EP1663842A2 (en) * | 2003-09-24 | 2006-06-07 | Cascade Corporation | Hydraulically-synchronized clamp for handling stacked loads of different sizes |
EP1589232A3 (en) * | 2004-04-23 | 2006-03-29 | Botschafter-Knopff, IIse | Hydraulic control device |
US8568079B2 (en) | 2012-02-15 | 2013-10-29 | Cascade Corporation | Rotator braking system for a lift truck load handler |
CN104555464A (en) * | 2014-12-28 | 2015-04-29 | 临颍县颍机机械制造有限公司 | High-lift four-drive agricultural embracing type grass gripping machine |
ITUB20160750A1 (en) * | 2016-02-15 | 2017-08-15 | Atlantic Fluid Tech S R L | Pilot operated flow diverter valve |
EP3205890A1 (en) * | 2016-02-15 | 2017-08-16 | Atlantic Fluid Tech S.r.l. | Piloted flow diverter valve |
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