Abstract:
An automatic hinge having an upper or left hand section with an arcuate interior or lower edge, a central section with an arcuate left hand or upper edge and an arcuate right hand or lower edge, and a lower or right hand section with an upper or interior edge. The sections are preferably cylindrical and the edges generally elliptical. A drive moves the central section linearly between the upper and lower sections. As the central and upper sections engage, the central section will rotate in one direction. As the central section engages the lower section, the central section will rotate in the opposite direction. A gate is preferably attached to the central section. By linearly moving the central section, the gate is lifted and turned. The preferred configuration allows the hinge to open a gate inward or outward in both a left hand mount and a right hand mount.

Description:
PRIORITY CLAIM  
       [0001]     This application claims priority of, and hereby incorporates by reference in its entirety, U.S. Provisional Application No. 60/546,517, filed Feb. 19, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates to swinging closing devices in general and to automatic gates in particular.  
         [0004]     2. Prior Art  
         [0005]     Automatic gates are known in the prior art. In one common type of automatic gate, the gate is mounted on a track. Upon activation, the gate is retracted along the track. This can pose a problem in that the terrain around the gate may not be flat. Where the gate is placed over a road or driveway, it will generally be desirable for the gate to fit flush against the road to prevent access to the secured property beneath the gate. If the terrain immediately surrounding the gate is uneven and particularly if it is upwardly inclined as is often the case in mountainous regions, retraction of the gate will be difficult if not impossible, unless the gate itself can flex, which can potentially compromise the integrity of the gate as a security device as well as provide an additional potential failure point in the gate retraction mechanism.  
         [0006]     Similar problems face swinging gates in uneven terrain. Frequently, the road or drive may rise in front of or behind a gate. As the gate swings out to open, it may encounter the rising drive, preventing it from opening fully. The problem can be addressed by simply raising the gate; however, this solution present its own set of problems in that the raised gate will no longer be in contact with the road or drive. This could allow intruders in or livestock out of the secured property.  
         [0007]     Gates that simultaneously lift and turn are known in the prior art as well. However, the rotational mechanisms for such gates are often limited to a particular application. A single gate system typically cannot be used to open both left hinged and right hinged gates. Nor can typical prior art lift and turn gates utilize a single mechanism for both inward and outward opening gates. The result is that most prior art lift and turn gates must be custom designed for each application. Accordingly, an automatic gate meeting the following objectives is desired.  
       OBJECTS OF THE INVENTION  
       [0008]     It is an object of the invention to provide an automatic gate that can be simultaneously lifted and opened.  
         [0009]     It is another object of the invention to provide an automatic gate that can be used in environments whose topography is not flat.  
         [0010]     It is still another object of the invention to provide an automatic gate that can be used to block roads and drives that rise proximately to the gate.  
         [0011]     It is still another object of the invention to provide an automatic gate mechanism that can be used with left hinged and right hinged gates.  
         [0012]     It is yet another object of the invention to provide an automatic gate mechanism that can be used with inward and outward opening gates.  
       SUMMARY OF THE INVENTION  
       [0013]     The preferred embodiment of the invention comprises an automatic gate hinge. In the preferred embodiment, the hinge comprises three sections: an upper section, a central section and a lower section. The upper section and lower sections are preferably fixed in place, while the central section is free to rotate with respect to either other section. A gate is operatively attached to the central section such that when the central section rises or falls, the gate rises or falls. Similarly, the gate is configured to swing as the central section turns.  
         [0014]     The facing edge of the sections are curved and configured to mate. Initially, the central section will rest on the lower section. An outside power source will lift the central section into contact with the upper section. As the central section continues to rise, the interaction between the edges of the central section and the upper section will cause the central section to rotate such that the central section will simultaneously rise and rotate. The attached gate will follow suit.  
         [0015]     As the central section is lowered, the interaction between the edges of the central section and the lower section will cause the lower section to fall and rotate simultaneously. A vertical section is provided in the lower edge of the central section and in the upper edge of the lower section to keep the central and lower sections in contact continuously. This allows the central section to begin to rotate as soon as it begins to fall and it allows the central section to fall vertically after its rotation is complete. Thus, the gate may be lifted, simultaneously lifted and rotated, simultaneously lowered and rotated, and then lowered. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1A  is a side view of a gate in the closed position.  
         [0017]      FIG. 1B  is a perspective view of a gate in the closed position.  
         [0018]      FIG. 2A  is side view of a gate lifting vertically out of the closed position.  
         [0019]      FIG. 2B  is perspective view of a gate lifting vertically out of the closed position.  
         [0020]      FIG. 3A  is a side view of a gate illustrating the simultaneous lift and turn motion of the gate as it is opened.  
         [0021]      FIG. 3B  is a perspective view of a gate illustrating the simultaneous lift and turn motion of the gate as it is opened.  
         [0022]      FIG. 4A  is a side view of a gate in the open position.  
         [0023]      FIG. 4B  is a perspective view of a gate in the open position.  
         [0024]      FIG. 5A  is a side view of a gate illustrating the simultaneous descend and turn motion of the gate as it is closed.  
         [0025]      FIG. 5B  is a perspective view of a gate illustrating the simultaneous descend and turn motion of the gate as it is closed.  
         [0026]      FIG. 6A  is side view of a gate descending vertically back into the closed position.  
         [0027]      FIG. 6B  is perspective view of a gate descending vertically back into the closed position.  
         [0028]      FIG. 7A  is an exploded view of a preferred embodiment of a hinge illustrating the lower section, the central section, upper section, sleeve, and hydraulic lift.  
         [0029]      FIG. 7B  is an exploded view of a preferred embodiment of a hinge illustrating the lower section, the central section, upper section, sleeve, and ball screw actuator lift.  
         [0030]      FIG. 8A  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge in the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0031]      FIG. 8B  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge rising vertically out of the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0032]      FIG. 8C  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge simultaneously rising and turning as the hinge opens. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0033]      FIG. 8D  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge in the open position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0034]      FIG. 8E  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge simultaneously descending and turning as the hinge closes. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0035]      FIG. 8F  is a perspective view illustrating a preferred embodiment of a left hand mount inward opening hinge descending back into the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0036]      FIG. 9A  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge in the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0037]      FIG. 9B  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge rising vertically out of the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0038]      FIG. 9C  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge simultaneously rising and turning as the hinge opens. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0039]      FIG. 9D  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge in the open position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0040]      FIG. 9E  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge simultaneously descending and turning as the hinge closes. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0041]      FIG. 9F  is a perspective view illustrating a preferred embodiment of a left hand mount outward opening hinge descending back into the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0042]      FIG. 10A  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge in the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0043]      FIG. 10B  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge rising vertically out of the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0044]      FIG. 10C  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge simultaneously rising and turning as the hinge opens. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0045]      FIG. 10D  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge in the open position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0046]      FIG. 10E  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge simultaneously descending and turning as the hinge closes. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0047]      FIG. 10F  is a perspective view illustrating a preferred embodiment of a right hand mount outward opening hinge descending back into the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0048]      FIG. 11A  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge in the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0049]      FIG. 11B  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge rising vertically out of the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0050]      FIG. 11C  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge simultaneously rising and turning as the hinge opens. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0051]      FIG. 11D  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge in the open position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0052]      FIG. 11E  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge simultaneously descending and turning as the hinge closes. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact.  
         [0053]      FIG. 11F  is a perspective view illustrating a preferred embodiment of a right hand mount inward opening hinge descending back into the closed position. The hinge is shown first without a sleeve, then with the sleeve shown cut-away, and finally with the sleeve intact. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0054]     The preferred embodiment of the invention comprises a gate  1  mounted on an automatic hinge  2  configured to simultaneously lift and rotate gate  1 . In the preferred embodiment, hinge  2  is comprised of three primary components: an upper or left hand section  3 ; a central section  4 ; and a lower or right hand section  5 . Lower section  5  and upper section  3  are preferably fixed in place, typically by mounting them to a gate post  7 . Upper section  3  is has a lower or interior edge  8 . In the preferred embodiment, lower edge  8  of upper section  3  is comprised of two mirror image halves,  8 A and  8 B. Halves  8 A and  8 B begin at a common lower or inner point  9  and diverge upward, meeting one hundred eighty degrees away on the other side of upper section  3  at upper or outer point  10 . The length of the vertical distance between lower point  9  and upper point  10  will be determined by the distance the gate designer desires gate  1  to rise during its rotation.  
         [0055]     Central section  4  also has an upper or left hand edge  11 . Upper edge  11  of central section  4  will mirror lower edge  8  of upper section  3 . Upper edge  11  has two halves  11 A and  11 B. Halves  11 A and  11 B will begin at a common upper or outer point  12  and diverge downward until they meet one hundred eighty degrees away at common lower or inner point  13 .  
         [0056]     Central section  4  is also provided with a lower or right hand edge  14 . Like upper edge  11 , lower edge  14  also has two halves  14 A and  14 B. Halves  14 A and  14 B begin at a common lower or inner point  15  and diverge upward to a common upper or outer point  16 . However, between lower point  15  and upper point  16 , each half  14 A,  14 B contains a vertical or linear break  17 A,  17 B.  
         [0057]     Lower section  5  has an upper or interior edge  18 . Upper edge  18  of lower section  5  will mirror lower edge  14  of central section  4 . Upper edge  18  has two halves  18 A and  18 B. Halves  18 A and  18 B will begin at a common upper or outer point  19  and diverge downward until they meet one hundred eighty degrees away at common lower or inner point  20 . Like lower edge  14  of central section  4 , each half  18 A,  18 B of upper edge  18  contains a vertical or linear break  21 A,  21 B between lower point  20  and upper point  19 .  
         [0058]     Gate  1  has a closed position  22  and an open position  23 . In closed position  22 , lower edge  14  of central section  4  will rest upon upper edge of  18  of lower section  5  and vertical breaks  17 A,  17 B will be aligned with their counterparts,  21 A,  21 B.  
         [0059]     Gate  1  is preferably provided with a lift or drive  24  configured to raise and lower central section  4  substantially vertically. In one preferred embodiment, lift  24  comprises a threaded shaft  25  configured to raise and lower central section  4 . Suitable threaded shaft lifts include ball screw actuators such as those available from Motion Systems of 600 Industrial Way West; Eatontown, N.J. In another preferred embodiment, lift  24  comprises an hydraulic cylinder  26  that raises and lowers central section  4 . Suitable hydraulic cylinder lifts and associated hydraulic pump packs include those available from Oildyne Products of 5520 Highway 169 North; Minneapolis, Minn. and from Aurora Air Products of 231 Ceola Road; Aurora, Ill. Whatever version of lift or drive  24  is used, the connection between lift  24  and central section  4  should preferably allow central section  4  to rotate relative to lift  24  while being raised or lowered.  
         [0060]     When lift  24  is activated, gate  1  will move out of closed position  22 . Because of the alignment of vertical breaks  17 A,  17 B with vertical breaks  21 A,  21 B, central section  4  will initially move straight up without any rotation. If gate  1  is to be locked, a lock may be provided which gate  1  engages and disengages via this initial and, as will be subsequently described, terminal vertical motion. When a lock is used, it should preferably be configured to disengage at the same time that lift  24  is activated.  
         [0061]     Central section  4  will rise vertically without rotation until upper edge  11  of central section  4  encounters lower edge  8  of upper section  3 . At this point, vertical breaks  17 A,  17 B in central section  4  should preferably be clear of vertical breaks  21 A,  21 B in lower section  5 .  
         [0062]     Lift  24  will continue to push central section  4  upward. However, once contact is made between central section  4  and upper section  3 , the interaction of lower edge  8  of upper section  3  and upper edge  11  of central section  4  will cause central section  4  to rotate as it rises. As central section  4  rotates, gate  1  will rotate as well. Thus, gate  1  will be simultaneously lifted and turned.  
         [0063]     It will be appreciated that the point along lower edge  8  of upper section  3  where upper edge  11  of central section  4  makes contact will determine how far gate  1  may be rotated and lifted by hinge  2 . Once upper point  19  of central section  4  reaches upper point  10  of upper section  3 , no further lifting or rotation of gate  4  will be possible with the present mechanism. If upper edge  11  initially contacts lower edge  8  at the midpoint between lower point  9  and upper point  10 , central section  4  and gate  1  will rotate about ninety degrees as central section is lifted through the remainder of its path. If upper edge  11  initially contacts lower edge  8  closer to lower point  9  than to upper point  10 , central section  4  and gate  1  will rotate more than ninety degrees. Similarly, if upper edge  11  initially contacts lower edge  8  closer to upper point  10  than to lower point  9 , central section  4  and gate  1  will rotate less than ninety degrees. Thus, the degree to which gate  1  rotates may be controlled by the alignment of central section  4  with upper section  3 . The reader will also appreciate that the maximum amount gate  1  is opened may be limited by controlling the height reached by lift  24 .  
         [0064]     When gate  1  is used to control access to a roadway, it will typically be configured to open about ninety degrees. However, where gate  1  is used for other purposes, such as for example controlling livestock or their access to pastures, greater or lesser degrees of opening may be desired.  
         [0065]     It will be further appreciated that the direction (clockwise vs. counterclockwise) in which central section  4  and gate  1  rotate will depend upon which side of lower point  9  upper edge  11  of central section  4  initially contacts lower edge  8  of upper section  3 . Thus, if the user wishes a left hinged gate, viewed from the interior of the secured property, to open inward, central section  4  will be positioned so that upper edge  11  of central section  4  first encounters lower edge  8  of upper section  3  on the half  8 A,  8 B of lower edge  8  that is on the interior side of gate  1 . Similarly, if it is desired that the same gate open outward, central section  4  will be positioned so that upper edge  11  of central section  4  first encounters lower edge  8  of upper section  3  on the half  8 A,  8 B of lower edge  8  that is on the exterior side of gate  1 .  
         [0066]     Hinge  2  can also be reversed for use on left and right hand hinged gates. If hinge  2  is installed as a left hand hinged inward opening gate, hinge  2  will be configured so that upper edge  11  of central section  4  first encounters lower edge  8  of upper section  3  on the half  8 A,  8 B of lower edge  8  that is on the interior side of gate  1 . If hinge  2  is moved to a right hand hinged gate, and the same configuration is used, gate  1  will open outward. If an inwardly opening right hand hinged gate is desired, hinge  2  need only be configured so that upper edge  11  of central section  4  first encounters lower edge  8  of upper section  3  on the half  8 A,  8 B of lower edge  8  that is on the exterior side of gate  1 .  
         [0067]     The direction in which gate  1  opens may also be controlled by turning mounting brackets  35  (discussed below) one hundred eighty degrees. This will allow the gate  1  to be changed from inward opening to outward opening without changing the direction of rotation of hinge  2  from clockwise to counter-clockwise.  
         [0068]     As will be appreciated by those skilled in the art, the reversibility of hinge  2  will provide distinct advantages. The installer does not have to either carry separate left and right mounting hardware to each installation or know whether a gate is to be a left hand or right hand gate before arriving at the job. Given the cost of many gate projects and especially custom gate projects as well as the remoteness of some gate installations, this can be a significant advantage, as a right hand or left hand error with prior art gates can result in costly and time consuming delays.  
         [0069]     When the user desires to close gate  1 , lift  24  will simply be operated in reverse. If central section  4  is not in contact with lower section  5  when lift  24  is reversed, gate  1  and central section  4  will descend linearly until lower edge  14  of central section  4  encounters upper edge  18  of lower section  5 . However, in the preferred embodiment, central section  4  is configured so that lower edge  14  of central section  4  remains in contact with upper edge  18  of lower section  5  continuously as central section  5  is rising and turning along lower edge  8  of upper section  3 . Thus, as soon as lift  24  is reversed and central section  4  begins to descend central section  4  will be in contact with lower section  5 .  
         [0070]     Lower edge  14  of central section  4  and upper edge  18  of lower section  5  will interact in substantially the same manner as upper edge  11  of central section  4  and lower edge  8  of upper section  3 . As lift  24  lowers central section  4 , lower edge  14  will encounter and ride along upper edge  18 , causing central section  4  and gate  1  to rotate as they descend. Lower edge  14  and upper edge  18  are angled in the opposite direction from upper edge  11  and lower edge  8 . Thus, central section  4  and gate  1  will rotate in the opposite direction upon descent as they did during ascent. Lower edge  14  and upper edge  18  should be angled to the same degree as lower edge  8  and upper edge  11 , so that central section  4  and gate  1  will fall the same distance during their closing rotation as they rose during their opening rotation.  
         [0071]     As lift  24  descends, central section  4  and gate  1  will rotate until vertical breaks  17 A,  17 B in lower edge  14  of central section  4  realign with vertical breaks  21 A,  21 B of upper edge  18  of lower section  5 . When vertical breaks  17 A,  17 B are aligned with vertical breaks  21 A,  21 B, central section  4  and gate  1  will descend vertically without rotation as lift  24  continues to descend.  
         [0072]     It will be appreciated that the total distance gate  1  rises will be determined by a combination of the length of vertical breaks  17 A,  17 B,  21 A,  21 B and the vertical distance between the point where upper edge  11  of central section  4  encounters lower edge  8  of upper section  3  and upper point  10  of lower edge  8  of upper section  3 . Lower edge  14  of central section  4  and upper edge  18  of lower section  5  should be configured so that central section  4  and gate  1  will descend the same distance.  
         [0073]     By configuring hinge  2  in the foregoing manner, hinge  2  will rotate and lower gate  1  through precisely the same path gate  1  took when it was opened. At the end of gate  1 &#39;s closing rotation, gate  1  will be lowered back into closed position  22 . If a lock is used with gate  1 , gate  1  will preferably engage the lock upon its descent back into closed position  22 .  
         [0074]     In the preferred embodiment, hinge  2  is provided with a sleeve  28 . Sleeve  28  will preferably comprise an exterior section  28 A and an interior section  28 B. In the preferred embodiment gate  1  is attached to sleeve  28  with mounting brackets  35 . In turn, sleeve  28  is attached to central section  4 . Thus, in the preferred embodiment, central section  4  is attached to gate  1  through sleeve  28  and brackets  35 . The attachment between central section  4  and sleeve  28  will cause sleeve  28  and attached gate  1  to rotate and rise or fall as central section  4  turns and rises or falls. Sleeve  28  is preferably positioned over the upper section  3  and lower section  5 . Sleeve  28  is configured to rise and fall on upper section  3  and lower section  4  as well as turn around them.  
         [0075]     In the preferred embodiment interior section  28 B of sleeve  28  preferably comprises an ultra high molecular weight plastic to facilitate (1) rotation of sleeve  28  around upper and lower sections  3 ,  5 ; (2) the rise and fall of sleeve  28  on upper and lower sections  3 ,  5 ; and (3) the prevention of movement among the internal components  3 ,  4 , and  5  of the hinge  2 , whereby the components may be kept in vertical or linear alignment with one another. Outer section  28 A is preferably made of aluminum. It will serve to protect the interior components of hinge  2 .  
         [0076]     The components of hinge  2  and gate  1  may be made out of virtually any strong solid material, including a wide variety of plastics and metals. The particular materials selected will depend upon the requirements and aesthetics of the particular application. However, in many applications, the inventor prefers to use aluminum for the components of hinge  2 . Particularly when gate  1  is intended to serve as a crash gate suitable for preventing intruders from driving through gate  1 , it may be desirable to use steel for the components of hinge  2 .  
         [0077]     It will be appreciated that the simultaneous lift and rotate mechanism of hinge  2  and gate  1  provide substantial advantages. Gated drives often rise, fall or turn just past the gate. Additionally, some drives have curbs or other obstructions on their sides. Gates that swing flat—without a rise—may strike the rising drive, terrain, curb, or other obstruction. This can prevent them from opening completely. If a flat swinging gate is mounted higher to accommodate the obstructions, the gate will not sit flat when it is closed, compromising its security function. The rise and lift configuration of the preferred embodiment allows it to clear most such obstructions as it opens. Moreover, because the preferred embodiment is configured to descend and rotate simultaneously through the same path taken during the opening rotation, obstacles overcome during opening will not pose a problem during closing.  
         [0078]     When hinge  2  is used to open and close gate  1 , gate  1  and lift  24  are preferably configured to operate on a twenty-four volt system. This will make the use of back-up battery power convenient. As the reader will appreciate, having battery back-up power for gate  1  will allow ingress and egress to the secured property even when municipal electrical power fails.  
         [0079]     In the preferred embodiment, gate  1  is provided with a circuit board  30  to govern the electrical systems of gate  1 . Circuit board  30  is preferably provided with a rectifier configured to convert the one hundred ten volt alternating current common in U.S. municipal power lines to twenty-four volt direct current. Additionally, circuit board  30  will be configured to charge the back-up battery or batteries as needed.  
         [0080]     Circuit board  30  is further configured to sense the torque exerted by gate  1  as reflected by increases in resistance. The torque exerted by gate  1  will increase if gate  1  strikes an object while opening or closing. Circuit board  30  is provided with a safety setting which will stop gate  1  if an increase in torque is detected during opening. The safety setting will also cause gate  1  to open if an increase in torque is detected during opening.  
         [0081]     In the preferred embodiment, the safety device is deactivated in the last few centimeters of gate movement. As upper point  12  of upper edge  11  of central section  4  meets upper point  10  of lower edge  8  of upper section  3 , central section  4  and upper section  3  will “nest.” This is desirable in that when gate  1  is open, it will be most steady in this position. However, when central section  4  and upper section  3  nest, an increase in torque may be detected by the safety setting. Therefore, a limit switch is provided in the preferred embodiment to deactivate the safety setting in the last few centimeters of the motion of gate  1 . The limit switch is provided on lift  24 . As lift  24  nears its maximum extension, lift  24  will trigger the limit switch which will deactivate the safety setting. As lift  24  begins to descend, the limit switch will be triggered again, reactivating the safety setting. Suitable limit switches are available from Elite Products of 25741 Commercentre Drive; Lake Forest, Calif. 92630.  
         [0082]     In the preferred embodiment, photo beams and receptors, such as the kind commonly used in garage doors, may be provided to detect if anything is in the path of gate  1  and to override any command to open or close gate  1 .  
         [0083]     Circuit board  30  may also be provided with a timer to automatically close gate  1  after a set period. Circuit board  30  is also preferably provided with a control setting that regulates the speed of gate  1  as it closes. Typically, the control setting will allow the user to slow gate  1  to about one third of its normal speed during the final third of its closing passage. This will prevent gate  1  from “closing hard” and potentially damaging gate  1  or such objects as may become positioned between gate  1  and, for example, the lock. Suitable circuit boards  30  may be obtained from Falco Electric of 1335 Winding Ridge; Colorado Springs, Colo.  
         [0084]     Although the preferred embodiment of the invention has been described in terms of a gate, the invention may be used in connection with any device that should open and close while simultaneously rising or falling. Examples could include doors, windows, valve gates, or other like devices. Additionally, it will be appreciated that while the present invention has been described as having a vertical configuration, hinge  2  could be positioned horizontally or in any other configuration and operate in the same manner.