US3466686A - Method and means for moving structures hydraulically - Google Patents

Description

Sept. 16, 1969' E. F. ALLEN METHOD AND MEANS FOR MOVING STRUCTURES HYDRAULICALLY Filed May 17, 1967 4 Sheets-Sheet 1 Hllll ai l INVENTOR. Q 5%: FAA/.5

Sept. 16, 1969 E. F. ALLEN 3,466,686

METHOD AND MEANS FOR MOVING STRUCTURES HYDRAULICALLY Filed May 17, 1967 4 Sheets-Sheet 2 3' INVENTOR. 444: F flLLE/Y ATTOP/YE) Sept. 16, 1969 E. F. ALLEN 7 3,466,686

METHOD AND MEANS FOR MOVING STRUCTURES HYDRAULICALLY Filed May 17, 1967 4 Sheets-Sheet '5 QINVENTOR. [41PM F A LEN BY 'nwnlw w Sept. 16, 1969 E. F. ALLEN 3,466,686

METHOD AND MEANS FOR MOVING STRUCTURES HYDRAULICALLY Filed May 17, 1967 4 Sheets-Sheet 4 INVENTOR. 599;:- F ALLOY United States Patent 3,466,686 METHOD AND MEANS FOR MOVING STRUCTURES HYDRAULICALLY Earle F. Allen, Norwell, Mass, assignor of one-half to Valentine E. Macy, Jr., New York, N.Y. Filed May 17, 1967, Ser. No. 639,192 Int. Cl. E01d 15/02; F151) 11/22 U.S. Cl. 14-42 16 Claims ABSTRACT OF THE DISCLOSURE A hydraulically actuated and controlled means for moving a structure such as a lift bridge or gate or similar structure where the motive power is hydraulically applied in such a manner that a directly applied hydraulic brake is combined with the hydraulic lifting means by a fail-safe control and additionally where the structure is kept continually level or at a predetermined attitude during its hydraulically powered movement by a leveling device positively controlling the movement of the structure by being directly coupled into the hydraulic power system.

The present invention relates to an improved method and means for hydraulically raising and lowering a structure and which is particularly adapted for raising and lowering elongated structures such as lift bridges or gates or similar structures where it is necessary to maintain a constant level or attitude for the structure throughout the movement.

The hydraulic method and means for applying the lifting power are uniquely adapted for the direct incorporation of both a fail-safe braking system and an integral leveling or attitude control.

Structures of this general type have heretofore been controlled by various electro-mechanical or hydraulic systems where separately applied controls were used for braking or arresting the structure movement and where the maintenance of a particular level or constant attitude was done by relatively complicated systems of mechanically coupled cables or electro-mechanical interlocks. These prior level controls require almost constant adjustment and in addition are subject to error from changes in the surrounding conditions including temperature variations.

The power and control system in accordance with the present invention employs hydraulic power cylinders preferably of the type as disclosed, for example, in applicants United States Patent No. 3,203,513 which describes a preferred form of hydraulic motor or drive cylinder which includes a fail-safe brake automatically applied to lock the cylinder pistons and thus the controlled structure whenever there is an intentional or an inadvertent loss of hydraulic pressure in the system. In addition, and as will be more fully explained below, a predetermined attitude of a structure such as a lift bridge is maintained during movement by a level sensing means included in the main hydraulic fluid supply system. The hydraulic motor movement is directly controlled by the level sensing means so that the system cannot continue to operate without including an attitude correction movement as will be evident from the following detailed description.

The above results are also obtained in a system using a relatively simple and fool-proof arrangement which is also uniquely suited for alternative operation at a number of spaced locations either on the structure itself or at a location remote therefrom. The relative simplicity of the preferred controls also uniquely adapts the system for a remotely controlled operation using communication channels including radio or cable links.

3,466,686 Patented Sept. 16, 1969 ice Accordingly, an object of the present invention is to provide an improved method and means for hydraulically actuating and controlling the movement of structures.

Another object of the present invention is to provide an improved method and means for hydraulically moving elongated structures such as lift bridges and the like with a precise control of the structure attitude.

Another object of the present invention is to provide an improved hydraulically operated means for moving structures including a simplified fail-safe braking system directly applied to the hydraulic drive motors.

Another object of the present invention is to provide an improved hydraulically operated drive means for lift bridges and other structures including means for automatically maintaining a level or other constant attitude of the driven structure.

Another object of the present invention is to provide a hydraulically operated drive system for moving structures having simplified control means including automatic leveling devices and adapted for remote control.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

FIG. 1 is a side elevational view partially in section and partially cut away illustrating a preferred embodiment of the hydraulic control and drive system applied to a vertical lift bridge;

FIG. 2 is a perspective view partially cut away illustrating a preferred embodiment of the hydraulic drive system coupled to one end of the structure of FIG. 1;

FIG. 3 is a diagrammatic perspective view of a preferred embodiment of an automatic means for maintaining a driven structure level or at another constant predetermined attitude;

FIG. 4 is a fragmentary top plan view of the attitude sensing means of FIG. 3;

FIG. 5 is a vertical sectional view of the sensing means taken along line 55 on FIG. 4;

FIG. 6 is a vertical sectional view of the attitude control valve taken along line 6-6 on FIG. 3; and

FIG. 7 is a schematic diagram illustrating the control system.

FIG. 1 illustrates a typical structure of the type to which the new hydraulic system isadvantageously applied. The structure illustrated in FIG. 1 is an elevated bridge 1 of the usual girder construction for spanning a river or canal or other space and which is movably mounted so that it may be raised from its lower position as shown in solid lines to the raised position shown in broken lines. The movable mounting for the bridge 1, as illustrated in FIG. 1, comprises a pair of vertically oriented lifting frames 2 having vertical lifting posts 3 movably positioned as for example between guide rollers 4 to permit vertical movement of the frames 2 and the attached bridge span 5. The movement of the bridge 1 is facilitated by the use of counterweights 6 at the opposite ends of the bridge I mounted on suitable pulleys 7 and. having the connecting cables 8 attached to the lifting frames 2 as illustrated at 9 in FIG. 2. Stairways 10 are illustrated at the opposite ends of the bridge 1 to facilitate access to the bridge 1 when it is in its raised position as shown in broken lines.

A preferred embodiment of a hydraulic drive system for raising and lowering the bridge is illustrated in FIG. 2.

The principal structural members of the bridge lifting frame are shown in FIG. 2 and consist of spaced vertical lifting posts 3 connected by relatively heavy and rigid horizontal frame members 11 and 12. The upper horizontal frame member 11 normally provides the basic support for the lower cross girders 13 (FIG. 1) of the bridge span 5. The upper griders 14 of the bridge span are conveniently attached to the upper portion of the lifting posts 3. In order to permit the raising and lowering of the lifting frames 2 during the bridge movement, end pits 15 are formed at both ends of the bridge 1 to receive the lower portions of the posts 3 and to enclose the lifting mechanism. The pits 15 normally have relatively heavy concrete or other water-tight wall structures 16 and include cross beams 17 for supporting the counterweight pulleys 7. The counterweights 6, as seen in FIG. 2, are conveniently positioned outwardly of the frames 2 on bearings 18. The spaced guide rollers 4 are also mounted on suitable brackets on the pit walls 16 to confine and guide the lifting frames 2 during their vertical movement.

In the preferred embodiment of the hydraulic drive system, one or more hydraulic drive motors 20 including cylinders 21 and pistons 22 are mounted with a generally vertical alignment with one end 23 connected to brackets 24 on a frame 2 and the opposite end 25 embedded in a suitable concrete or other support member 26. These hydraulic drive motors 20 are arranged to be in their shortened position when the bridge 1 is lowered and are extended by the hydraulic drive and control system, to be described below, to raise the frames 2 and the attached bridge 1 to its upper position as illustrated in the broken lines in FIGS. 1 and 2. Both the upper and lower couplings for the hydraulic drive motor 20 are arranged to permit a moderate amount of swinging motion particularly at the tops of the hydraulic drive motor 20 such as might be experienced due to the expansion and contraction of the bridge structure during temperature variations.

As will be apparent from the description of the hydraulic drive which follows, this slight swinging movement of the cylinders has no effect on the movement of the bridge by the motor 20 or on maintaining the horizontal alignment of the bridge 1 since the expansion is experienced equally at opposite ends and as minor variations in the leveling of the bridge are automatically compensated for in the preferred hydraulic control system to be described.

While two drive motors 20 are illustrated in FIG. 2 it will be clear that one or more cylinders may be used at each end of the driven structure depending upon the over-all weight and width of the bridge or other structure being moved.

The system control cabinet is illustrated in FIG. 1 positioned on the bridge structure 1 itself. This cabinet 30 may conveniently contain all the necessary drive and control elements for the hydraulic drive and control system described below. It will include, for example, the supply of hydraulic fluid together with the motor to establish the necessary hydraulic pressure as well as the various valves and indicators that control or indicate system pressures. In the simplest version of the system, the only external coupling required is a power line to couple electric power in the necessary amounts to the control cabinet. This conveniently may be a loosely looped cable 31 running between the cabinet 30 and an electric supply line and provided with suitable slack to accommodate the necessary bridge motion. The necessar control devices for the hydraulic pressure motor as well as the control valves and safety devices for operating the hydraulic drive motors 20 may be mounted at the cabinet. If desired, additional controls may be connected in parallel with those in cabinet 30 by suitable extensions of the control hydraulic lines or by using a second set of controls electrically coupled in parallel to those on the bridge 1 and permitting remote operation of the bridge control system.

FIG. 7 illustrates a preferred embodiment of the control system for raising and lowering the bridge 1. With the exception of the hydraulic motors 20 and the hydraulic lines connected thereto, the elements illustrated in FIG. 7 may be conveniently positioned in the control cabinet 30 which may be completely closed and locked when the system is not in use. A central control panel 34 is provided in cabinet 30 to mount the various switches and valves which operate the hydraulic lift system. A reservoir 35 for the hydraulic fluid provides for a suitably large reserve so that the system may be operated for long periods without the addition of fluid. An electrically operated pump 36 has its inlet connected to the reservoir 35 and its outlet coupled through a main control valve 37 to each of the hydraulic motors 20. In the preferred embodiment, the control valve 37 is an electrically operated valve with its control solenoid coupled to valve control switch 38 which is conveniently positioned on the control panel 34. The valve 37 has a neutral position and raise and lower positions which are controlled by the appropriate manipulation of the control handle 38. When the control 38 is in its neutral position, conduits 39 and 40 which are coupled to the ends of the hydraulic cylinders 21 are both disconnected from pump 36. When the control handle 38 is moved to its raise position, the line 39 is connected by valve 37 to the pump 36 through line 42 causing the pistons 22 to be forced outwardly of the hydraulic cylinders 21, and the opposite end of each hydraulic motor 20 is coupled by line 40, valve 37, and line 41 to the reservoir 35. As will be further discussed below, a bridge level control valve 43 is included in line 39 to automatically control the bridge attitude. The level control valve 43 is operatively connected to a level sensing means which may be a gyro-controlled platform or a dilferential or other level indicator.

When it is desired to lower the span 5, the control handle '38 is moved to reverse these connections so that lines 40 are coupled to the pump 36 through conduit 42 by valve 37 and the opposite ends of the hydraulic motors 20 are coupled to the reservoir 35 through conduit 50, an additional level control valve 51, valve 37 and conduit 41.

The rate of movement of the span 5 is conveniently controlled in the preferred embodiment by placing a flow control valve 44 in the high pressure pump line 42. The valve 44 is conveniently positioned on the control panel 34. A pressure relief valve 48 is also conveniently positioned on the control panel 34 and the valve 48 connects between the pump high pressure outlet line 42 and the reservoir 35 through line 46 to prevent the system pressure from rising above a predetermined value. A motor control switch 49 for the electrically driven pump motor 36 is also mounted on the control panel 34. Pressure gages for the system are also mounted on the control panel 34. Thus, a pressure gage 47 is provided to register the pressure in the high pressure pump line 42 and gages 52 and 53 are connected in the pressure lines 39 and 40 for indicating the span raising and lowering pressures respectively.

A hydraulically operated brake 56 is mounted on each of the hydraulic motors 20 so that the piston rods 22 may be tightly locked at any position when it is desired to hold the span 5 against movement. These brakes 56 which may be of the type described in United States Patent No. 3,203,513 are each coupled to high pressure line 42 through conduit 57, control valve 58 and connecting lines 59. Valve 58 is moved to its open position to connect each of the brakes 56 to the high pressure fluid to move the brakes to their open position. The brakes 56 are applied to the piston rods 22 through internal spring pressure in each brake 56 by moving the valve 58 to its closed position which cuts off the high pressure bydraulic fluid source from the connecting lines 59 and couples these lines to the hydraulic reservoir 35 through a brake release line 60.

In order to raise the bridge span 5, the electric motor for the pump 36 is first energized by switch 49. The brakes 56 are next released by opening the valve 58 and the control valve 38 is then moved to its raise position. In order to lower the bridge, the valve 38 is moved to its lower position with the brakes in their off position.

The preferred embodiment of the brakes 56 are of the fail-safe type and are applied by mechanical Spring forces independent of the hydraulic system. This permits the span 5 to be held at any position including its 'fully raised position even though the hydraulic pressure fails due to a failure in the system or due to the intentional shutting down of the pump 36. It also results in the automatic application of the brakes 56 whenever the hydraulic pressure fails.

In the preferred embodiment, an alternate emergency system is provided to permit the span 5 to be raised or lowered by any independent hydraulic system such as that which might be provided on a portable compressor. This emergency system includes valves 61 and 62 to isolate the raising and lowering conduits 39 and 40. Quick disconnects 63 and 64 are included in the lines 39 and 40 to permit the application of the outside hydraulic pressure as necessary to move the bridge either upwardly or down- Wardly after the valves 61 and 62 have been closed.

In order to insure proper movement of relatively heavy structures such as lift bridges or dams or other supporting structures of this general type it is desirable that the structure be kept level or in predetermined attitude. The hydraulic system as described above is particularly adapted for a novel level control means.

One embodiment of such a control means is illustrated in FIGS. 36. A principal element in this control is a mechanical differential having spring loaded drums 70 and 71 connected to differential gears 72 and 73 having its spider 74 operatively connected to the level control valves 43 and 51 by a suitable linkage 75.

As best seen in FIG. 3, the drums 70 and 71 have lengths of control cable 76 and 77 wound around them with the ends of the cables extending through suitable closed conduits and over end pulleys 78 and 79 to fastenings 80 and 81 on the opposite bridge end pits 15 or other supports. It is evident that as long as the bridge or other structure maintains its original attitude during its upward or downward movement, equal lengths of cable will be released or returned to the spring loaded drums 70 and 71. During this type of normal operation it is also clear that there will be no resultant movement of the differential spider 74 and no change in oil flow through the connected valves 43 and 51. Should the moving structure tend to become misaligned, however, it is evident that more cable will be withdrawn or rewound with respect to one drum 70 or 71 than the other causing the differential spider to turn. The valves 43 or 51, as best illustrated by valve 43 in FIG. 6, are arranged to provide for equal fluid flow to the drive motors 20 at opposite ends of the structure during normal operation but to be turned during a misalignment to reduce hydraulic flow to the high end of the structure and to increase or maintain the regular flow to the low end of the structure. It is clear that the valve may be proportioned, if desired, so that flow to the low end of the bridge may be completely cut oif should a misalignment reach a critical angle. The level control valve 51 is similarly arranged so that during the bridge lowering fluid flow is decreased from the low end and is increased from the high end as the drain lines 50 are used to control the motor movement in this case. It is clear that the necessary differential flow may be controlled in the motor supply lines or drain lines or both and that a single level control valve may be used and switched between the raising and lowering circuits. With a valve and a control system of this type installed there is no reason the critical misalignment should occur however when the critical angle is reached and when all hydraulic fluid is applied to the low end correction must result. The valve obviously may also be proportioned so that all hydraulic fluid flow may be cut off and a suitable alarm device operated in the event the misalignment proceeds beyond a critical stage to a dangerous amount.

It will be seen that the present invention provides an improved control means for moving structures including relatively heavy ones such as lift bridges and the like where an automatic fail-safe operation is made an integral part of the drive system and in addition where precise reliable leveling or attitude control is readily made an integral part of the system. These improved results are obtained in a system capable of applying substantial amounts of power and which is at the same time simply and eifectively controlled either directly on the structure itself or at conveniently connected remote control stations.

The hydraulic power system including the related failsafe braking and leveling means are also readily adaptable for emergency operation through easily connected external hydraulic sources so that the controlled structures may be operated by portable compressor systems in the absence of or the failure of the regular power supply. The power and control systems are also suited for use with a variety of structures and are easily installed and maintained in view of their relative simplicity and of the relatively few critical or moving parts required.

As various changes may be made in the form, construction and arrangement of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim:

1. In a drive system for a movable structure having hydraulic powered drive means the improvement which comprises a source of hydraulic fluid under pressure positioned on the movable structure including a reservoir and a pump, first coupling means for coupling the pump output selectively to the drive means consisting of mechanicalhydraulic means including means for alternatively coupling the drive means to a second source of hydraulic fluid under pressure through at least a portion of said first coupling means.

2. The system as claimed in claim 1 in which said hydraulic drive means comprises a hydraulic drive cylinder and a cooperating movable piston, and a brake for said piston having integral resilient means for applying the brake to the piston and hydraulic means for acting against the resilient means for releasing the brake and being removably coupled to the pump output.

3. The drive system as claimed in claim 1 which further comprises a leveling control including an attitude sensing means mounted on said structure, and a fluid control valve operatively connected to said sensing means and positioned in communication with the first said coupling means.

4. In a drive system for a structure movably mounted for motion with a substantially constant attitude and having hydraulically powered drive means including coupling means for coupling a source of hydraulic pressure to the drive means the improvement which comprises a structure attitude sensing means mounted on said structure, and leveling valve means operatively connected to said sensing means and included in said hydraulic coupling means for maintaining by mechanical-hydraulic means only a relatively constant structure attitude during structure movement by said drive means.

5. The system as claimed in claim 4 in which said hydraulic drive means comprises a hydraulic drive cylinder and cooperating movable piston, and a brake for engaging said piston and having integral resilient means for applying the brake to the piston, and hydraulic means for acting against the resilient means for releasing the brake and being removably coupled to the output of said pump.

6. In a drive system for a structure movably mounted for motion with a substantially constant attitude with respect to the support and having a plurality of hydraulically powered drive means coupled at spaced points between said structure and said support and including means for coupling said drive means individually to a source of hydraulic fluid under pressure the improvement which comprises structure attitude sensing means mounted on said structure, and levelling valve means operatively connected to said sensing means and including flow controlling means consisting of mechanical-hydraulic means in the coupling for each of said drive means for maintaining the relatively constant structure attitude during structure movement by said plurality of drive means.

7. The drive system as claimed in claim 6 in which said attitude sensing means comprises a mechanical differential coupled to the structure support at spaced points.

8. The drive system as claimed in claim 6 in which said sensing means comprises a stabilized reference platform.

9. The drive system as claimed in claim 6 in which said sensing means comprises a gyro stabilized platform.

10. In a drive system for a structure movably mounted for substantially vertical motion from its support with a substantially constant horizontal attitude maintained by mechanical-hydraulic means and having hydraulically powered drive means coupled at opposite ends of said structure the improvement which comprises said drive means comprising elongated substantially vertically oriented hydraulic cylinders and cooperating pistons, and said cylinders being pivotally coupled to said structure and to said support whereby the structure attitude is independent of structure expansion and contraction.

11. An improved method of hydraulically moving a structure and maintaining by mechanical-hydraulic operations only a constant structure attitude with respect to its support comprising the steps of moving the structure with individually controlled and spaced hydraulic drive means, continually sensing the changes in attitude of said moving structure, and automatically operating the individual controls in accordance with the attitude sensing.

12. The method as claimed in claim 11 in which the sensing step comprises differentiating between the levels of spaced portions of the structure by coupling a differential indicator to spaced points on its support.

13. An improved method of vertically raising an elongated lift bridge and of maintaining a generally horizontal bridge attitude comprising the steps of moving the bridge with individually controlled and spaced hydraulic drive means positioned at opposite ends of the bridge, continually sensing the changes in attitude from the horizontal of said moving bridge, and controlling the flow of hydraulic fluid to the drive means by mechanical-hydraulic operations only in accordance with the attitude sensing to maintain the bridge in a generally horizontal position.

14. The method as claimed in claim 13 in which the sensing step comprises differentiating between the levels of opposite ends of the bridge by mechanically coupling a difierential indicator to the bridge support at both ends.

15. In a drive system for a structure movably mounted for motion with a substantially constant attitude with respect to its support and having a plurality of hydraulically powered drive means coupled at spaced points between said structure and said support and including means for coupling said drive means individually to a source of hydraulic fluid under pressure the improvement which comprises structure attitude sensing means mounted on said structure comprising a mechanical differential having one input gear coupled to the structure support at one point and the other input gear coupled to the structure support at a spaced point, and leveling valve means operatively connected to the differential spider arm of said attitude sensing means and including how controlling means in the coupling for each of said drive means for maintaining the relatively constant structure attitude during structure movement by said plurality of drive means.

16. In a drive system for an elongated relatively horizontal lift bridge movably mounted for motion with a substantially constant attitude with respect to its support and having a plurality of hydraulically powered drive means coupled at spaced points between said structure and said support and including means for coupling said drive means individually to a source of hydraulic fiuid under pressure the improvement which comprises structure attitude sensing means mounted on said structure, said attitude sensing means comprising a mechanical differential having one input gear coupled to the bridge support at one end of the bridge and the other input gear coupled to the bridge support at the other end of said bridge, and leveling valve means operatively connected to the differential spider arm of said attitude sensing means and including flow controlling means in the coupling for each of said drive means for maintaining the relatively constant structure attitude during structure movement by said plurality of drive means.

References Cited UNITED STATES PATENTS 100,910 3/1870 McNeale 1442 704,611 7/1902 Brown 14-42 X 1,352,450 9/1920 Henderson 1442 2,128,273 8/1938 Stevens 2806 2,443,657 6/1948 King 1442 X 2,883,594 4/1959 Alberts 318-19 2,889,565 6/1959 Harty 1442 2,904,911 9/1959 Colee 37-156 3,203,513 8/1965 Allen 188170 3,230,846 1/1966 Curlett 9446 NILE C. BYERS, 1a., Primary Examiner.

U.S. Cl. X.R. 52

Images