US2909899A

US2909899A - Gate elevating mechanism

Info

Publication number: US2909899A
Application number: US665454A
Authority: US
Inventors: Charles D Ramsden; Ray C Weidenbach
Original assignee: PACIFIC COAST ENG CO
Current assignee: PACIFIC COAST ENG CO; PACIFIC COAST ENGINEERING Co
Priority date: 1957-06-13
Filing date: 1957-06-13
Publication date: 1959-10-27
Anticipated expiration: 1976-10-27

Description

Oct. 27, 1959 c, RAMSDEN EIAL 2,909,899

' GATE ELEVATING MECHANISM 4 Sheets-Sheet 1 Filed June 13, 1957 INVENTORS Charles D. Ramsden BY Ray C. Weidenbach J44 QA.

Attorneys Oct. 27, 1959 c, RAMSDEN EI'AL 2,909,899

GATE ELEVATING MECHANISM Filed June 15. 1957 '4 Sheets-Sheet 2 Fig.2

/ I4 43 l 42 F i I8 UUULIULIUUUULIIJULILIULILILIULI I! LLLLLW INVENTORS Charles D. Ramsden BY Ra y C. Weidenbach Attorneys TLIULILIULIIJ Oct. 27, 1959 c, RAMSDEN ET AL 2,909,899

GATE ELEVATING MECHANISM Filed June 13, 1957 4 Sheets-Sheet 5 \INVENTORS Charles D Ramsden BY Ray C. Weidenbach EZZA 9 M Attorneys Filed June 13, 1957 Fig.6

c. D. RAYMSDEN El AL 2,909,899

GATE ELEVATING MECHANISM 4 Sheets-Sheet 4 z. y INVENTORS Charles D.Ramsden BY Ra y C. Weidenbach Attorneys United States. Patent GATE ELEVATING IVIECHANISM Charles D. Ramsden, Alameda, and Ray C. Weidenbach, Oakland, Calif., assignors to Pacific Coast Engineering Company, Alameda, Calif., a corporation of California Application June 13, 1957, Serial No. 665,454

2 Claims. (Cl. 61-25) This invention relates to a gate" hoisting mechanism and particularly to such a mechanism which is easily and readily adjustable.

The gate consists generally of a circular sector, with its convex surface upstream against the water face, which is supported by means of struts leadingito a pivot at the center of the sector. The gates are usually made of structural steel throughout although in some instances the circular sector may be composed of steel covered with a creosoted wooden facing. These gates lie in the spillways of a dam and the pivots about which they are raised are secured to the walls or to piers of the dams.

Generally the gates are raised or lowered by chains or ropes which are secured to hoists.

A typical hoist arrangement would consist of a suitable electric motor and gear reduction unit mounted on one wall or pier immediately adjacent the spillway and a similar gear reduction unit on the adjacent pier or wall. The two gear reduction units are joined by a shaft connection, a pinion in one unit and a similar pinion in the other.

Each gear train assembly serves to actuate a substantially identical sprocket or rope drum. The sprockets or drums are coaxially aligned and are adapted to engage chains which are secured to the bottom edge of the gate adjacent the side edges thereof.

The conventional gate hoist construction just described requires the use of two rather massive and expensive gear train assemblies, one on each side of the spillway.

It is an object of this invention to provide a gate hoist assembly which eliminates the use of one of these gear trains.

The adjustment of the chains of the conventional gate hoist arrangement has previously been accomplished by changing the connection between the flanges on the ends of the cross shaft and the end of the driving and driven shafts upon which the pinions are secured. Since the adjustment, when made in this manner, is made at such an early stage in the gear reduction assembly, it is apparent that it is unnecessary to provide an auxiliary means for a fine adjustment. This is for the reason that the adjustment is made to a shaft connection which may rotate at approximately 50 to 100 rpm. whereas the ultimately driven sprockets will rotate at less than one revolution per minute because of the intervening gear trains.

It is a further object of this invention to provide a gate hoist arrangement which eliminates the utilization of a second expensive and massive gear train assembly and which provides means for readily adjusting the cross shaft to compensate for minute differences in length of the chains.

It is a further object of this invention to provide a simplified mechanism for mounting the cross shaft in such a manner that adjustments of either sprocket may be made within a matter of a few degrees or of a small fraction of an inch in accordance with a predetermined schedule or table.

These and other objects and advantages of our inven- 2,909,899 Patented Oct. 27, 1959 ice tion will appear from the following specification taken in conjunction with the accompanying drawing in which:

Figure l is a cross-section schematic view taken through the spillway of a conventional dam showing the mounting of a gate.

Figure 2 is a schematic plan view of a dam showing a gate in place.

Figure 3 is a planview of a gate hoist assembly il1ustrating the driving and driven portions thereof.

Figure 4 is an enlarged detail of a portion of the driving unit.

Figure 5 is a similar enlarged detail view of a driven unit.

Figure 6 is an enlarged cross-sectional view of the drive end coupling.

Figure 7 is an end view of a drive end coupling shown in Figure 6.

Figure 8 is a cross-sectional view of a driven end coupling.

Figure 9 is an end view of illustrated in Figure 8, and

Figure 10 is a view, partially in cross-section, of a driving shaft adapted to connect the drive end coupling and the driven end coupling.

As indicated generally in Figures 1 and 2 a dam is provided with a single or a plurality of spillways each the driven end coupling of which is adapted to be closed by a gate 10. The face and lowered by means of a pair of chains or cables 14 which are connected to the lower edge 16 of the face 11 of the gate 10 and which are reeved over suitable sprockets or drums 17 and are connected again at 18 at the upper edge of the face 11 of the gate 10. By actuating the sprockets 17 therefore the gate 10 will be raised or lowered to open or close the spillway.

As indicated particularly in Figure 3 a conventional gate hoist arrangement made pursuant to our invention consists of a plurality of substantially identical units which are adapted to be mounted upon the walls or piers of the dam. Each unit consists generally of a so-called driving assembly and an idler assembly.

The driving assembly as illustrated in Figure 3 con-' sists of a suitable electric motor 21 which is mounted upon a prefabricated frame assembly 22. Each frame assembly 22 must be specifically designed to accommodate the assembly to each dam.

The motor 21 is operatively connected to helical gear reducer 23 which, in turn, through a coupling 24, drives a worm gear reducer 26. A suitable control panel 27 is provided whereby an operator may control the assembly to raise and lower the gate and such control may be responsive to remote control or to on the spot control.

We provide a suitable drive shaft 28 to which a pinion 29 is suitably keyed (Figure 4). -The pinion 29 is in constant mesh with gear 31 which is suitably keyed to a sprocket and spur gear shaft 32 mounted in

suitable bearings

33 and 34 which are likewise secured to the frame 22. The sprocket and spur gear shaft 32 also supports and drives a sprocket 36. Thus it will be" seen that the sprocket 36 is actuated through a motor 21,

helical gear reducer 23, gear reducer 26, pinion 29 and with a number of holes. In the specific example which we are disclosing herein the flange 411 is provided with 18 holes.

The driven or idler assembly on the remote side of the spillway opening which is adapted to be actuated by the mechanism thus far described is identical to the idler or driven assembly illustrated in the left hand side of Figure 3, and in Figure 5. Generally speaking the driven or idler assembly consists of an idler pinion gear shaft 42 which is mounted upon suitable bearings. Shaft 42 is provided with a coupling similar to that illustrated in Figures 8 and 9 which is keyed thereto and which consists of a hub 39a and a flange 41a but in this instance the flange is provided with 19 holes. A pinion 29a (Figure is suitably keyed to the shaft 42 and is in constant mesh with a gear 31a which is keyed to a sprocket and spur gear shaft 32a and actuates a sprocket 36a keyed thereto. The

sprockets

36 and 36a are substantially identical.

In order to connect the driving and driven portions of our assembly We provide a connecting shaft 43 between the members 41 and 41a. The connecting shaft 43 may be formed from a piece of inch pipe. The drive end coupling 39 is adapted to be moved longitudinally along the shaft 28. This may be accomplished by providing a slip-key and key-way assembly which prevents rotation of the hub 39 with respect to the shaft 28 and a plurality of set screws which are threadedly mounted in the hub 39 and which are adapted to engage the shaft 28. When they engage the shaft 28 it is obvious that longitudinal movement of the hub 39 will not occur.

The

hubs

39 and 39a are each provided with annular shoulders 42 and 42a. The ends of the drive shaft 43 are provided with

parallel flanges

44 and 46. The flange 44 we shall refer to as the driven end flange and it is of substantially the same outside diameter as the flange 41 and is provided with a corresponding number of holes, in this case, eighteen. The flange 44 is also provided with a coaxially aligned bore 47 Whose diameter is substantially identical to the outside diameter of the hub 42. The flange 46 is the same diameter as the flange 41a and it too is provided with the same number of holes as the flange 41a, in this instance, nineteen. It too is provided with a bore which is adapted to cooperate with the hub 42a on the flange 41a. The driving flange 41 and the driven flange 41a are adapted to be connected by the drive shaft 43 and the drive shaft 43 is adapted to be connected to these members in the following manner. The shaft 43 is hoisted to a proper position and the flange 41 is retracted along the shaft 28. The driven flange 41a and the flange 46 are bolted together and the bore in the flange 46 and the shoulder or hub 42a cooperate to provide proper alignment for the flanges 46 and 41a. The other end of the shaft 43 is brought into coaxial alignment with the shaft 28 and the coupling member is slid outwardly along the shaft 28 until the

flanges

41 and 44 are in engagement. The two are then bolted together and the set screws in the hub 39 are tightened. The tightening of the set screws prevents longitudinal movement of the drive end rigid coupling longitudinally along the shaft 28. It is thus apparent that when the drive shaft 28 is actuated, the driven shaft 42 will likewise be actuated. It is equally obvious that when the sprocket 36 is driven, the sprocket 36a will be driven at the same rate of speed.

Operation of this assembly may briefly be described as follows. Let it be assumed that the gate 19 is in lowered position as illustrated generally in Figure 1 and that it is desired that the same be raised to permit the passage of water over the spillway. The chains 14 are in engagement with the

sprockets

36 and 36a. The operator, through the controls 27 causes the motor 21. to be actuated and through the assembly previously described, the

sprockets

36 and 36a are driven. The gate will be 4 raised. When it is desired that the gate be lowered, the motor 21 is reversed and the gate 10 is lowered.

It will be apparent from the foregoing that we have provided a gate hoist assembly which eliminates the use of one massive and expensive gear train assembly.

As has previously been indicated there are a greater number of holes in the

flanges

41 and 44 than there are in the flanges 41a and 46.

Let it be assumed that as the mechanism is being installed it becomes apparent that the chains 14 need adjustment and that, unless there are adjustments, one of the chains would assume the whole load thus putting undue strain upon one side of the gate and on the hoisting mechanism associated with that chain. It is apparent that proper operation of the gate requires that the load be distributed evenly upon both chains.

In order to adjust the chains it would of course be possible to make some adjustment at the point of connection between the chains and gate. However this is not desirable. Therefore we have provided means for effecting adjustment by varying the positions of the

sprockets

36 and 36a with respect to each other. It is apparent that the increment of movement of one sprocket with respect to the other must be rather small in order to provide for fine adjustment. The means for providing this fine adjustment resides in the differences between the number of holes in the

flanges

41 and 44 on the one part and the flanges 41a and 46 on the other. For purposes of clarity we shall refer to the

flanges

41 and 44 as the drive end coupling flanges and the flanges 41a and 46 as the driven end flanges.

As has previously been pointed out there are 18 holes in the drive end flanges and 19 holes in each of the driven end flanges. It is apparent therefore that there is a distance of 20 degrees between the holes in the drive end flanges while the distance between the holes in the driven end couplings will be approximately 19 degrees. By way of specific illustration let it be assumed that the outside diameter of the flanges is 14 /2 inches and that the diameter of the circle defining the centers of the holes is 13 inches, also that the pitch diameter of the

sprockets

36, 36a is 27.78 inches, and that the final gear drive ratio is 88/17 or 5.18. The distances between the centers of the holes of the two sets of flanges will be approximately 0.115 inch, which distance is further reduced by gearing to approximately 0.049 inch at the sprocket pitch line. In other words the typical chain adjustment table would be as follows:

Approxi- Number Decimal mate of holes fraction to rotate 049 %4 l 098 A2 2 148 4 3 197 s" 4 246 4 5 295 %4 6 344 1 2 7 394 m 8 442 M 9 It will be apparent therefore that if the bolts in one of the coupling members are removed and the cooperating flanges are rotated with respect to each other, there will be a difference in the adjustment of the

sprockets

36 and 36a. Operation of our adjusting means may briefly be described as follows: The hoist is operated in such a manner that the gate is lowered to its full extent. The end of the downward travel would be indicated in the limit switch assembly 3'7. An operator should check to ascertain that the gate is properly seated. The op erating end of the chain at point 16 should be slightly slack and the end of the chain attached at 18 should be very slack. The hoist assembly is then locked against rotation; that is, further rotations of the sprockets and movements of the chain is prohibited either by wedging or by some other braking means. The operator then refers to the foregoing table to determine the coupling adjustment based upon the estimated chain adjustment desired. Preferably he should then mark the coupling flanges to show their assembly at the present time and these markings will constitute reference points. The coupling bolts are then removed from both the drive end coupling and the driven end coupling. The member 43 will be prevented from falling into the spillway by the hubs 42 and 4211.

Let it be assumed that the idler hoist chain is to be tightened. In the first place the limit switch assembly 37 should be rendered inoperative. The cross shaft 43 is then rotated the number of holes on the idler end coupling as determined from the preceding table. The shaft 43 is turned in the direction it would be turned in raising the gate 10. The bolts are then replaced in the idler end coupling. The hoist is operated in a lowering direction until the drive coupling flange 41 is rotated to the first mating flange bolt hole. The bolts are then replaced in the drive end coupling. The limit switch is then reactivated and the wedges blocking or braking means are removed from the hoist assembly. The gate is then tested. If further adjustment is needed the operation is repeated until accurate adjustment is obtained.

In the event the chain of the drive hoist side is to be tightened, the cross shaft is rotated the number of holes as determined from the table and shaft is turned as it would be rotated if the gate were being lowered. The coupling bolts are replaced in the idler end coupling. The hoist is operated in a manner corresponding to the raising or elevating manner until the drive coupling holes immediately adjacent the original setting are aligned. Coupling bolts are replaced in the drive end coupling and the gate is tested.

It is apparent from the foregoing therefore that by providing couplings have varying numbers of holes therein a fine adjustment will be obtained by our device.

It is to be appreciated of course that types of reduction mechanisms other than the helical gear reducer 23 may be utilized. Moreover various elements of the driving mechanism may be omitted in certain constructions and others substituted in their stead.

While I have shown the shaft 43 in a preferred position, it is to be understood of course that it may be mounted at a point between the two sprockets 36 and 36A. It is apparent that regardless of its positioning the shaft must support itself across the span. 2

We claim:

1. In a gate hoist construction adapted to raise and lower a gate to control the passage of water over the spillway of a dam, a hoist construction comprising a driving unit and a driven unit, said driving unit being mounted on one of the piers, and comprising a motor, a gear reduction assembly, and gear and pinion assembly and a sprocket, the driven unit on the other of said piers comprising a pinion and gear assembly and sprocket and a cross shaft connecting said driving and driven portions, said cross shaft including means for varying the relationship between said sprockets comprising a drive end coupling adjacent one end of said cross shaft and a driven end coupling adjacent the other end of said cross shaft, each of said couplings comprising a cooperating pair of relatively rotatable, coaxial parallel flanges, means for locking the flanges of said couplings against rotation comprising bolts received within threaded orifices in each of said flanges, the drive end coupling being provided with a predetermined number of orifices and the driven end coupling being provided with more of said orifices than said drive end coupling.

2. In a gate hoist construction adapted to raise and lower a gate to control the passage of water over the spillway of a dam, a hoist construction comprising a driving unit and a driven unit, said driving unit being mounted on one of the piers, and comprising a motor, a gear reduction assembly, and gear and pinion assembly and a sprocket, the driven unit on the other said piers comprising a pinion and gear assembly and sprocket, and a cross shaft connecting said driving and driven portions, said cross shaft including means for varying the relationship between said sprockets comprising a drive end coupling adjacent one end of said cross shaft and a driven end coupling adjacent the other end of said shaft, each of said couplings comprising a cooperating pair of separate coaxial parallel flanges, means for connecting each of said pair of flanges comprising bolts received within threaded orifices in each of said flanges, the drive end coupling being provided with a predetermined number of orifices and the driven end coupling being provided with one more of said orifices than said drive end coupling, the flange portions of each of said couplings having the same number of coaxially aligned orifices, the flanges on said drive end coupling being mounted so as to be moved laterally into and out of engagement with one another.

References Cited in the file of this patent UNITED STATES PATENTS 117,028 Wood July 11, 1871 344,878 Tainter July 6, 1886 1,057,928 Briggs Apr. 1, 1913 1,307,160 Stokes June 17, 1919 2,051,359 Adams Aug. 18, 1936 2,089,700 Kidder Aug. 10, 1937 2,250,448 Edwards July 29, 1941