Abstract:
A sliding member operating system is disclosed which includes a adjustable pressure regulator (18)fluid control valves (15), (40), (50), (30), (80), (20), and (70) and an operating cylinder (60) which is mounted to the sliding element of a door or window (66) and its adjacent frame (62) for the purpose of opening and closing and holding said sliding element. This system utilizes the fluid being exhausted from cylinder (60) during the closing cycle to hold open valve (30) insuring that a door or window in motion will continue to stay in motion but that the power being supplied to a moving door or window, once halted by any means, will cease. An additional series of valves is utilized to pressurize cylinder 60 for the purpose of holding a door or window in the closed position. The rate of fluid bleed at valve 50 is adjustable to control closing speed and the sensitivity at which the sliding element will stop if an object is encountered during the closing cycle or if the door/window closes completely.

Description:
This application claims the benefit of U.S. Provisional Application Ser. No. 60/006,780 filed Nov. 15, 1995. 
     This invention relates to an operating system which utilizes a regulated fluid, a power cylinder and a series of valves for the purpose of opening, closing and locking sliding doors and windows in a safe and gentle manner. 
     BACKGROUND OF THE INVENTION 
     Prior fluid powered operating systems that have been developed for controlling the movement of sliding doors and windows utilize electrical interface methods to operate control valves. This method substantially adds to the cost and complexity of these devices rendering this technology of little value as a means of retrofitting doors and windows commonly found in the typical residence or business. These known devices include a variety of electrical switches and sensors for the purpose of controlling movement, sensing location and permitting these units to operate in a safe manner. 
     Electro-mechanical systems have also been developed for a similar purpose. These units utilize an electric motor and mechanical means  a cable or chain for example! to provide movement and necessarily complex electrical sensors for control. As with prior fluid powered systems, the complexity and associated cost render these devices of little value in the home or office. 
     It is therefore desired from the standpoint of cost, ease of assembly and operation, safety, number of parts, and reliability, an operating system that is suitable for retrofitting existing doors and windows, easy to install, easy to relocate, is inexpensive, reliable, compact, quiet, and inherently safe in operation. 
     SUMMARY OF THE INVENTION 
     It is the object of the present invention to provide a low cost door/window operating system. 
     It is a further object of this invention to provide an operating system which is gentle in its movement and otherwise safe to use. 
     It is yet another object of this invention to provide a door/window operating system which is easy to install, assemble and maintain. 
     It is still another object of the present invention to provide a door/window operating system suitable for retro-fitting existing doors and windows, that is easy to relocate, and can be utilized in an equal capacity with new construction of dwellings and places of business. 
     It is another object of this invention to provide a means of holding sliding doors and windows in the open or closed position. 
     It is a still further object of this invention to provide a door/window operating system which does not substantially interfere with the normal manual operation of said door or window. 
     Accordingly, the present invention achieves these objects with the use of a source of compressed fluid, a series of valves, a pressure regulator, and an operating cylinder functionally mounted to a sliding door or window and its adjacent frame. This system does not utilize electricity for any purpose other than the possible initial activation of the unit or the possible production of compressed fluid. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a schematic view of the basic door operating system according to the present invention when the door is in the fully closed position and the system is deactivated. 
     FIG. 2 shows a schematic view of the basic door operating system according to the present invention when the system is activated and the door is moving toward the open position. 
     FIG. 3 shows a schematic view of the basic door operating system according to the present invention when the system is deactivated and the door is moving toward the closed position. 
     FIG. 4 shows a schematic view of the door operating system according to the present invention when the door is in the fully closed position with the cylinder locked with fluid pressure. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the above described Figures, the basic door operating system 10 includes a pressurized fluid tank 12; a shut off valve for said tank 14; a pressure regulator 18 with an adjusting knob 18a; tubing 16 with tubing sections 16a through 16j; an adjustable throttle valve 15; a set of valves 30 and 40; and an additional adjustable valve venting to the atmosphere 50. Additionally, a fluid pressure operated cylinder 60 is securely mounted to a frame 62, and a rod 64 is securely mounted to a sliding door 66. A stationary door 68 is mounted adjacent to sliding door 66. 
     Valve 30 includes a biasing member, for example, a spring 31 which is connected to a spool 34. Spool 34 includes fluid channels 34a, 34b and a cap 34c. Additionally valve 30 contains an orifice 16d allowing fluid to pass from tubing section 16c to vent to the atmosphere. Valve 30 also contains a chamber 32, which when pressurized, acts against the biasing member shifting the spool 34. This device described as Valve 30 is commonly referred to as a pressure activated three way valve. Valve 30 is operatively connected to tubing sections 16c, 16e, and also to 16f which conveys fluid whose purpose is to activate this valve. 
     Valve 40 comprises a spool member 44 having channels 44a, 44b and caps 44c and 44d. Spool 44 is operatively connected to a solenoid 46 which is capable of displacing the spool 44 upon activation of electrical switch 48. Valve 40 is operatively connected to tubing sections 16h, 16i, and 16j. This device is commonly referred to as a three way solenoid valve. 
     OPERATION OF THE BASIC SYSTEM 
     Referring first to the conditions of FIG. 1, we can observe that fluid under pressure in tank 12 is capped at 44d in valve 40 and at 34c in valve 30. There is no flow of fluid in this state of deactivation. The door 66 is however free to move manually because both ports of cylinder 60 are open to the atmosphere. One through tubing 16c, fluid channel 34b, and vent 16d. The other through tubing 16j, fluid channel 44a, tubing 16h, and valve 50. It is therefore apparent that door 66 will operate in a normal manner by anyone not choosing to use the operating device. 
     Referring next to FIG. 2, where the operator has activated switch 48 causing spool 44 of valve 40 to shift so that channel 44b will be in fluid communication with tubing sections 16i and 16j, thereby permitting fluid to flow to cylinder 60. Cylinder 60 in this pressurized state will cause rod 64 to move in the direction of arrow B, and door 66 will thereby be moved to the open position. Valve 15 is adjustable to control the opening speed of door 66 and cooperates with regulator 18 for this purpose. As the piston in cylinder 60 moves, it forces the fluid on the other side of the piston into tubing section 16c, through channel 34b of valve 30, and finally to the atmosphere at vent 16d. Pressure will continue to act on the cylinder piston until the door 66 is fully open and remain in this state until such time as the operator chooses otherwise. 
     Referring next to FIG. 3, it is apparent that the operator has deactivated switch 48 which has caused spool 44 to shift to it&#39;s previous position of alignment with tubing sections 16j and 16h. The fluid which was captive under pressure in cylinder 60 now is free to flow through tubing 16j, to channel 44a, out of valve 40 to tubing 16h. It is then metered to the atmosphere through valve 50 at such a rate that tubing section 16f and chamber 32 of valve 30 will remain pressurized for a period of time sufficient to cause spool 34 to shift so that channel 34a is in alignment with tubing sections 16e and 16c. Tubing 16e contains pressurized fluid which is now free to pass through channel 34a and tubing 16c to cylinder 60 thereby forcing the piston of cylinder 60 to move in the direction of arrow A. The pressurized fluid will thus be supplied to cylinder 60 from valve 30 only as long as sufficient pressure exists in chamber 32 to maintain the spool 34 in its position of alignment with tubing sections 16e and 16c. It is important to note that as the piston in cylinder 60 is moving in the direction of arrow A, fluid will continue to be forced along its path to valve 50 and chamber 32 thereby maintaining spool 34 in its present position of alignment only as long as door 66 continues to move toward the closed position. When the piston of cylinder 60 stops, which is when the door is fully closed or is stopped by an object while it is closing, no more fluid is forced to wend its way to chamber 32, and therefore spool 34 will be biased back to its original position as shown in FIG. 1 and FIG. 2. At this point the door operating system 10 has come full circle back to its original conditions and is once again free to be easily moved manually. 
     It is also important to note that the rate of fluid passage at valve 50 is directly related to the sensitivity at which the door will be brought to a stop such that a preferred adjustment of valve 50 will cause the door 66 to come to a gentle stop when coming to the closed position or upon encountering an object. Moreover the slowing of the rate of fluid passage at valve 50 also has a direct effect on the speed the door will close and cooperates with regulator 18 in this respect. 
     Referring again to FIG. 1, the operating cycle during manual use of the door, will more closely be examined. A manual movement of the door forces fluid from the cylinder, into tubing section 16c, through valve 30 by way of passage 34b and finally to the atmosphere at vent 16d. This flow of fluid is not substantially restricted by any means. Correspondingly, this same movement draws fluid from tubing section 16j, through valve 40 by way of passage 44a, through tubing section 16h and valve 50. In the preferred embodiment of this invention valve 50 is of the type that meters flow to the atmosphere while permitting fluid to flow freely in the opposite direction.  Pneumadyne inc. model FC-52 or others! The flow diagram above valve 50 shows this flow pattern. Since there is essentially no restriction of the fluid passage in this direction there is essentially no impedance to the manual opening of the door. However, when a manual closing cycle is initiated, fluid flows backward through the path just described. In this case a partial restriction does occur which causes pressure to build up. This pressure build up causes the same reaction of valve 30 previously described and referred to in detail in FIG. 3. Therefore, manual operation of a door is unimpeded in the opening direction and power operated in the closing direction. 
     DETAILED DESCRIPTION OF THE LOCKING DEVICE 
     Referring now to FIG. 4 it is shown that the basic operating system 10 has been modified with the addition of valve 20, throttle valve 80, tubing sections 16a, 16b, 16k and 16m, and valve 70. Valve 20 operates in substantially the same manner as valve 40 previously described. Valve 70 includes a biasing member 71, spool 74 fluid passage 74a and cap 74c. Valve 80 is a simple throttle valve and is substantially the same as valve 15. Tubing section 16c shown in FIG. 1, FIG. 2 and FIG. 3 is conspicuously absent. 
     OPERATION OF THE LOCKING DEVICE 
     The conditions shown in FIG. 4 are that switch 28 has been activated, usually but not necessarily by remote control, which moves spool 24 so that fluid channel 24b is in fluid communication with tubing section 16m and 16b. Valve 70 is being acted upon by the edge of door 66 in such a manner as to shift spool 74 so that channel 74a is in fluid communication with tubing sections 16b and 16a. Since tubing section 16a is connected to the high pressure fluid supply of tank 12, fluid is free to flow directly into cylinder 60 thus holding the door in this locked position. It should be observed that valve 70 must be in the depressed mode to permit fluid to enter cylinder 60. This is a safety device so that the system cannot be activated unless door 66 is in the fully closed position therefore eliminating the possibility that this locking system can be used to close door 66 in an unsafe manner. Valve 80 is an additional back-up safety device so that if fluid is permitted to pass through valve 70 it will be restricted in its path to cylinder 60 thereby making the locking of door 66 occur slowly and if, for any reason, door 66 should be made to close under the higher pressure supplied through valve 70, this closing movement will occur in a slow, safe manner. If door 66 is forcibly moved in the opening direction against the fluid pressure being supplied, the biasing member 71 of valve 70 will cause spool 74 to shift so that tubing section 16b will be capped. Further movement of door 66 will therefore cause the captive fluid in cylinder 60, already under relatively high pressure, to be further compressed therefore increasing dramatically the amount of force necessary to continue movement of door 66. It can be observed, although not shown by a separate drawing, that when switch 28 is deactivated, valve 20 will revert back to a condition where tubing sections 16m and 16k are in the direct communication. The operation of this three way valve is substantially the same as valve 40 which can be referenced in FIG. 1 and FIG. 2. In this state of deactivation, fluid is free to pass to or from valve 30 by way of tubing section 16k, fluid channel 24a and tubing section 16m, to or from cylinder 60 thereby duplicating the original conditions supplied by tubing section 16c. This enables the basic operating system 10 to once again function normally. 
     PRACTICAL APPLICATION OF THE INVENTION 
     The practical application of this invention on sliding doors has, up to this point, been the focused use of this invention. It is to be understood by persons of ordinary skill in the art that the invention is not strictly limited to such embodiments, but may be otherwise variously embodied and practiced within the scope of the following discussion. 
     Generally speaking, the construction methods and materials used in the installation of windows, various gates and other sliding members is the same as that of doors. These methods consist of the construction of a framed opening of the proper size, the subsequent attachment of pre-hung units, and final trimming with moldings commonly known as casement moldings. Therefore, because the motions involved are substantially the same, this invention has direct application in the automatic operation of sliding windows and, with the cylinder mounted vertically, with double hung windows. The usefulness of the locking mechanism described in detail in FIG. 4 also functions substantially the same and has the same practical application on sliding windows and double hung windows as it does on sliding doors. 
     The mounting hardware used in the practical application of this invention is of the type commonly available and in general use with pneumatic cylinders. No claim is being made as to the uniqueness of their use with this invention. 
     In the full embodiment of this invention, electrical switches 48 and 28 of FIG. 4 would most commonly be controlled by a hand held transmitter and a receiver for the purpose of remote activation. A degree of security is therefore provided as these known devices have many possible codes. It is however known to a person skilled in this art that any method used to make an electrical contact would be adaptable for use with this device. A further adaptation is the substitution of compressed fluid pilot valves in lieu of the previously mentioned electric valves. These three way valves of the same configuration as valve 32 and will respond to a signal of compressed fluid rather than an electrical impulse yielding an increase in the versatility of control systems. An obvious use of this type of control would be to equip a door for public access without the use of retrofitting electric wires. It is interesting to note that compressed fluid is commonly available for sale in specially designed cylinders, such as Carbon dioxide, Nitrogen, Oxygen for example!. These cylinders, equipped with a suitable regulator, have the practical application of usage with this invention to render the system completely free of the use of electricity. 
     It is the applicant&#39;s opinion that the most practical embodiment of this invention is to give people with a physical disability a greater degree of control of their environment.