US2024724A - Counterweight system - Google Patents

Description

Dec. 17, 1935.

w. w. EAGER ET AL y 2,024,724

COUNTERWEIGHT .SYSTEM Filed Sept. 13, 1952 j-NVENT nl; 5 WWER @E11 Patented Dec. 17, 1935 COUNTERWEIGHT SYSTEM -Wesley W. Eager, Los Angeles, and Columbus A. Tierney, San Marino, Calif.

Application September 13, 1932, Serial No. 632,943

21 Claims. (Cl. ,Z0-19) r trice 15.: terbalanced in such a manner that the door will This invention relates to counterweight systems, and has for an object the provision of a highly eicient counterweight system, which is particularly designed for, but not necessarily llimited to, use in conjunction with the closure forming the subject matter of our oo-pending application Serial No. 620,884, led July 5, 1932. The present invention is a division in part and in part is an improvement over the subject matter ,of the said co-pending application.

A more detailed object is the provision of a counterweight system whereby any suitable load, such as a door mounted for swinging movement about a horizontal axis, can eiectively be counremain without fastening in any position to which it can be moved.

Another object is to provide a counterweight system wherein the weight whereby the load is `counterbalanced is carried by a system of me- .system which comprises a container adapted to be transported and mounted in operative relation to the remainder of the counterweight system when empty and consequently much lighter than when in actual use when it is filled to the proper level with any suitable weighting material, By employing a container of rectangular cross-sectional conguration and of appropriate dimensions, it is especially adapted to receive a pluraliiy of common bricks, which t nicely therein, and of which the appropriate number may be supplied to aggregate the necessary weight.

Another object is to provide a counterweight system of the general class described in which are employed especially eiiicient means for connecting the counterweight to the load, so as to prevent as much rictional resistance to the movement of the parts as possible, thereby enhancing the ease with which the device can be operated and increasing the length of time during which it can be used without necessitating repair or replacement of parts.

A further object is to provide a device of the general character described, in the design of which particular attention has been paid to efliciency kand ease of operation, simplicity and ruggedness of construction, facility of assembly and durability and general serviceability of the assembled mechanism.

The invention possesses other objects and valuable features, some of which, with the foregoing, will be set forth in the following description of the preferred form of our invention. It is to be understood that we do not limit ourselves to the specific disclosure made by the said description,

as we may adopt variations of the preferred form 10 within the scope of our invention, as set forth in the claims.

Referring to the drawing:

Figure 1 is a transverse, Vertical sectional View taken through a door and showing in side elevation a counterweight system operably associated therewith and constructed in accordance with the principles of our invention.

Figure 2 is a View similar to Figure 1 but showing the door and counterweight system in the opposite extremes of their respective movements.

Figure 3 is a horizontal sectional View, the plane of section being indicated by the line 3 3 of Figure 2, with the direction of View as indicated by the arrows.

Figure 4 is a View in side elevation of a portion of a slightly modified form of our improved counterweight system.

Figure 5 is a View similar to Figure 4, but showing another slightly modied form.

For the purpose of the present disclosure, one embodiment of our improved counterweight system has been illustrated upon Figures 1 to 3 inclusive, as being operatively associated with a 'door 6 mounted for pivotal movement about the 35 horizontal axis of a bearing or journal 'l in such a manner that when closed the door 6 occupies a vertical position as illustrated upon Figure 2, in closing relation to an opening 3 in a wall or partition 9, and when open occupies a horizontal, 40

overhead position, extending through the opening 8, as illustrated upon Figure l. Inasmuch as the details of construction and method of mounting of the door 6 form the subject matter of our co-pending application, mentioned hereinabove, suffice it for the purpose of the present disclosure to explain that the means for pivotally Amounting the door comprises a plurality of aligned brackets H (only one of which is illustrated) rigid with the wall or partition 9, and

preferably a similar number of brackets l2, each of which is rigid with the door 6. Each of the stationary brackets il comprises a leg I3 inclining upwards and inwards from the wall 9 and another leg Vllt inclining downwards and inwards v from the wall S to intersect the leg I3 and be rigidly joined thereto. Each of the stationary brackets II carries one of the journals 'I through which a stub shaft IB extends, all of these shafts I5 being in axial alignment and providing the kmeans for pivotally supporting the door 6. This is accomplished by rigidly fastening as by a nut Il each of the door brackets i2 to an end of the associated stub shaft I6, as best illustrated upon Figure 3. As is also explained in our previously led application, reference to which has been made hereinabove, the alined axes of the stub', shafts lie within the plane which also includes the center of gravity of the door 6 and which inclines upwards and inwards at substantially 45 with respect to the plane of the door E. It should be understood that whereas we have illustrated our improved counterweight system as being operatively associated with a door 6 of the type forming the subject matter of our aforesaid co-pending application, we do not wish to be limited to such use of our counterweight system, inasmuch as it is adaptable to various other types of closures and, indeed, in a great many installations where it is desirable to provide an efficient counterweight for practically any type of load.

As many of the improved counterweight systems as may be desirable or necessary are employed with each door or closure 6. However, inasmuch as all those employed with each door are of identical counstruction, it will be suificient to describe but one of them. This counterweight system which is indicated in its entirety at 2| is connected to its load (i. e., the door 6) through the expedient of an arm 22 which is rigidly connected'as by a nut 23 to the end of the stub shaft I6 opposite that to which the associated door bracket I2 is connected, This is an important detail of construction of our device inasmuch as 40 it distributes the force applied by the counterweight system 2| and the force applied by the door 3 upon opposite sides of the journal 1, thereby preventing the twisting effect upon the bracket I I carrying the journal 'I which would be applied thereto were both these forces applied at the same end of the journal "I, This assists in holding all the said shafts I6 accurately in coaxial alignment and thus reduces to an absolute minimum the frictional resistance to motion of the stub shafts IG within their respective journals 'I.

The arm 22 is pivotally connected as by a pin 26 to a lever 21; and from one end 28 of the lever 2l a counterweight 2S is suspended, as will readily be understood from observation of Figures l and 2, As is also explained in application Serial No. 620,884, of which this application is a division in part, the axis of the pin 26 whereby the force of the counterweight 29 is applied to the arm22, also lies within the plane which includes the axes of the stub shafts and the center of gravity of the door 6. Hence the respective turning moments of the door and of the counterweight 29 about the axes of the stub shafts are always equal to each other, regardless of the position to which the door is moved. The result of this feature is that the counterweight system is able to sustain the door motionless in any position to which the door can be moved, without the necessity of fastening the door in that position. These figures show that when the door swings from closed position (Figure 2) to open position (Figure l), the arm 22 swings downwards through 90 of rotation about the axis of the journal 'I, carrying with it the pin 26 which is connected to the mid-portion of the lever 2l. As the pin 26 moves downwards, the lever 21 swings in clockwise direction about the axis of a pin 32 whereby a roller 33 is journaled on the other end 3G of the lever 2l, and the pin 3i whereby the weight 29 is pivotally connected to the lever 21 will also 5 move downwards but through twice the distance traversed by the pin 26. Thus, it may be seen that the moment of the force exerted by the counterweight 29 is equal to the weight ofthe counterweight 29 ,multiplied by the distance between 10 and the claims. Similarly, the effective length 20 of the end 28 of the lever 2l will be considered as designating the distance between the axes of the pins 3| and 26; and the effective length of the'end 3|! of the lever 2l will be considered to indicate the distance between the axis of the pin 25 2t and the pin 32. The distance between the axes of the pins 26 and 32 is equal to the distance between the axes of the pins 26 and 3|, i. e., the effective length of the end 30 of the lever is equal to the effective length 23 thereof; and each of 30 these distances is equal to the effective length of the arm 22.

Inasmuch as the axes of the shaft Il and the pin 32 about which the arm 22 and lever 2l,

respectively, turn, are spaced apart and since 35 the arm 22 and lever 2'I are interconnected by the pin 23, it is necessary to compensate for their arcuate movements in opposite directions in order to permit freedom of movement of the meinbers. In the modification illustrated, this is ac- 4, complished by permitting the pin 32 to vary its distance from the shaft I'I, preferably by movement in a horizontal path. Accordingly, means are provided for guiding the roller 33 for movement with its axis in the horizontal plane which 4 includes the axis of the journal i. In this manner, a moving fulcrum for the lever 2l is provided. This guiding means comprises a track 36 preferably in the form of an angle iron which may conveniently be a horizontal extension of 5 either of the legs I3 or I4, say the leg I3 of the stationary bracket II. VThe roller 33 is disposed in rolling engagement with the track 36; and the parts are so proportioned and arranged that the axis of the pin 32 is disposed in parallelism 5 with and in horiontal alignment with the axis of the journal "I,

Owing to the equality of the effective lengths of the arm 22 and the ends 23 and Sil of the lever 21, the pin 3| whereupon the counterweight 29 is 6 suspended, will traverse a perfectly straight, vertical path in moving from one extreme of its motion to the other. This follows from the fact that even though both the arm 22 and the end 23 of the lever swing about their respective axes 65 .movementof the lever 21 which permits ythe pin 3| to move in a truly vertical pathis madepossible lby the moving fulcrum for the lever 21 which is provided by the roller 33-and track36. As the arm`22 swings downwards fromthe position illustrated upon Figure-2 toward that position in which it extends horizontally, the entire lever 21 swings in clockwise rotation `with the end3 moving inwards away fromfthe wall 9, and after the horizontal position of the arm V22 has been passed, these parts move back rtoward the Wall 9. These movements of the lever 21 occur in reverse order as the counterweight 2B is being raised, i. e. while the door is being closed; and the consequent motion of the pin 32 carried by the end 30 of the lever 21 toward and away from the axis-of the bearing 1 is made possible because of the rolling engagement of the roller 33 upon the track 35.

Figure 4 shows a slightly modiiied formi of device for providing this moving fulcrum. I-Iere the lower leg I3 of the stationary bracket I', instead of being bent to horizontality, is continued straight on beyond the journal 1"and hasa link 4| pivoted to its upper end as by a pin 42. 'I'he lever 21 upon which the counterweight (not shown) is suspended is pivoted intermediate its ends to the arm 22 which is rigid with'the load (not shown) and which is constructed similarly Ato the arm 22 of the previously described modification. The end 30 of the lever 21' which is opposite the end 28' from which the counterweight is suspended is pivoted to the link 4| as by a pin 43. Hence, the link 4| isvoontinually in compression, it being understood that the counterweight tends to make the lever 21' rotate in a clockwise direction about the pin 26' whereby the lever 21 is pivoted tothe arm22'. The link 4| is enabled to swingfrom the full line position shown upon Figure 4 to the dotted line position, thereby permitting the shifting of the pin 43 which is analogous to the horizontal movement of the pin 42 whereupon the roller 33 is journaled. 'It should be explained, however, that in this modiication, owing to the slight deviation of the pin 43 from truly horizontalmovement, the movement of the counterweight is not as accurately in a straight vertical line as in the case of the previously described modication.

Figure 5 shows still another modified form which is identical with that illustrated upon Figure 4, with the exception that itis the upper leg I4" instead of the lower leg I3" of the stationary bracket which is extended to provide the stationary support for the link 45 to which the after end 35 of the lever 21" vis pivoted. In this modification the link 46 is continually under tension.

Another advantage gained as a result oi using the construction hereinabove described is that the lever 21 never moves to vertical position. In the lowermost position of the counterweight, the lever inclines downwards from the pin 32 at substantially 45, and as the counterweight moves upwards, the lever 21 swings upwards until it inclines upwards from the pin 32 at substantially 45. Hence, the lever 21 is always inclined at least substantially 45 from the vertical, the result being that the turning moment of the counterweight, as well as that of the door 6, is always in excess of zero. The importance of this is that at least a portion of the forces exerted by the counterweight and the door are exerted directly against each other at all times, thereby taking up all lost motion, and the parts cannot be swung to a positionwherein anylloo'sen'ess ini the bearings or other` parts will permit the door to vmoveeven slightly without a corresponding movement of `the counterweight.

The construction of the counterweight 29 is 5 another important detail of our invention. Although the entire counterweight system would operate with equal eiliciency with any type of suitable weight, we prefer to employ a hollow conltainer5| suspended in a suitable hanger 52 from 10 porting said closure, a counterweight, and means 25 'interconnecting said-closure and said counterweight whereby their respective turning moments about said pivot means are equal to each other in all positions of said closure.

2. In combination, a closure, pivotmeans sup- 30 porting said closure for movement'about a horizontal axis, a counterweight, and means interconnecting said closure and said counterweight Ywherebyr their respective turning moments about said pivot means are equal to each other in all 35 positions of said closure.

3. In combination, a closure, pivot means supporting said closure for movement about a horizontal axis and supporting the entireweiglit of said closure in all positions thereof, a counter- 40 weight, and means interconnecting said closure and said counterweight whereby their respective turning moments about said pivot means areequal to each other in all positions of said closure.

4. In combination, a closure, pivot means sup- 45 porting said closure for movement about a horizontal axis, and Vmeans for releasably retaining said closure in any position to which it can be moved comprising a counterweight and means operatively connecting said counterweight 'to 'said 50 closure .and supporting said counterweight for movement proportionally with the movement of said closure and in a substantially straight line.

5. A counterweight system for balancing apredetermined load mounted upon a supporting 55 structure for movement about a given axis, comprising an arm rigid with said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, -and means movably con- 60 necting the other end of said lever to said supporting structure.

6. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a given axis, com- 65 prising an arm rigid with said load and extending `beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, and means connecting the other end of said lever to said supporting struc- 70 ture and for guiding said other end in movement substantially in a plane including said axis.

7. A counterweight system fo-r'balancing a predetermined load mounted upon la supporting structure 'for movement about a given axis, com- 775 prisingan arm rigid with said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, and means connecting the other end of said lever to said supporting structure and for guiding said other end toward and away from said axis.

8. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a given axis, comprising an arm rigid with said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, and means connecting the other end of said lever to said supporting struc- -ture and for guiding said other end, and means providing a movable fulcrum for the other end 'of said lever.

9. A counterweight system for balancing a predetermined load mounted upon a supporting Cil structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, and means movably retaining the other end or" said lever substantially Within the horizontal plane of said axis.

-10. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, a roller journalled upon the other end of said lever, and a track rigid with said supporting structure and guiding said roller in movement toward and away from said axis.

11. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, a roller journalled upon the other end of said lever, and a track rigid with said supporting means and guiding said roller for movement with the axis thereof substantially within the horizontal plane in cluding the axis of movement of said load.

l2. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, a track rigid with said supporting structure, and means on the other end of said lever guided by said track in movement toward and away from said axis.

13. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, and means movably retaining the other end of said lever substantially within the horizontal plane of said axis, the effective length of each end of said lever and Vthe effective length of said arm from said axis to said lever being equal.

14. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis,

comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a weight carried by one end of said lever, a roller journalled upon the other end of. said lever, and a track 5 rigid with said supporting means and guiding said roller for movement with the axis thereof substantially within the horizontal plane including the axis of movement of said load, the effective length of each end of said lever and the effective length of said arm from said axis of movement of said load to said lever being equal.

15. A counterweight system for balancing a predetermined load mounted upon a supporting structure for movement about a horizontal axis, comprising an arm connected to said load and extending beyond said axis therefrom, a lever pivoted between its ends to said arm, a Weight carried by one end of Said lever, a link pivoted at one end to said supporting structure and at its other end to the other end of. said lever to retain said other end of said lever substantially within the horizontal plane of said axis, the eiective length of each end of said lever and the effective length of said arm from said axis to said lever being equal,

16. In a counterweight system for balancing a load, a counterweight, and guiding means therefor comprising a supporting structure, an arm pivotally Vmounted thereon for movement about a given axis and operably connected to said load, a lever pivoted between its ends to said arm, said counterweight being connected to an end of said lever, and means guiding the other end of said lever for movement toward and away from said axis.

17. In a counterbalancing device for a load pivotally mounted for movement about a horizontal axis, comprising an arm extending from said load beyond said axis of movement thereof, a lever pivoted intermediate its ends to said arm at a point beyond said axis of movement of said load from the load itself, said point, the center of gravity of said load, and said axis of pivotal movement of said load all lying in a common plane, a weight connected to said lever adjacent one end thereof, and means for guiding the other end of said lever in a substantially horizontal path.

18, In a counterbalancing device for a load pivotally mounted upon a supporting structure, an 50.

arm extending from said load beyond the axis of pivotal movement thereof, a lever, a counterweight carried by said lever, means connecting said lever to said supporting structure and providing a fulcrum about which said lever is adapted to swing, and means connecting said lever to said arm whereby the arm is caused to swing in arcuate motion opposite to that of the lever, at least one of said connecting means including means for compensating for the arcuate movements of said arm and lever.

19. In a counterbalancing device for a load pivotally mounted upon a supporting structure, an arm extending from said load beyond the axis ofV pivotal movement thereof, a lever, a counterweight carried by said lever, means connecting said lever to said supporting structure and providing a. fulcrum about which said lever is adapted to swing, and means connecting said lever to said arm whereby` the arm is caused to swing in arcuate motion opposite to that of the lever, at least one of said connecting means being movable with respect to one of the members interconnected thereby to compensate for the arcuate movements of said arm and lever. 75.

20. n combination, a closure, 'pivot means supporting said closure, a oounterweight and means interconnecting said closure and said counterweight whereby their respective turning moments about said pvot means are always in excess of zero and are equal to each other in al1 positions of said closure.

21. In combination, a closure, pivot means supporting said closure, a counterweight and means interconnecting said closure and said counterweight whereby their respective turning moments about said pivot means are always in excess of zero and whereby the ratio between said. turning 5 moments is maintained substantially constant.

WESLEY W. EAGER. COLUMBUS A. TIERNEY.

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