A WINDOW OPENING AND CLOSING DEVICE

Abstract: A window opening and closing device comprises a housing adapted to be mounted to a window sill or window frame or integrally formed as part of a window sill or frame, two flexible coil arms extending from within the housing to be connected at their outer ends to a window sash, and an extension and retraction mechanism within the housing comprising at least one worm gear and means on the inner ends of the flexible coil arms engaging the worm gear(s) so that on rotation of the worm gear(s) one way or the other the flexible coil arms are extended from or retracted into the housing. The device may be operated manually and/or by an electric stepper motor.

Description: A WINDOW OPENING AND CLOSING DEVICE FIELD OF INVENTION The invention comprises an opening and closing device for a window and particularly but not exclusively a high mounted window. BACKGROUND OF INVENTION High windows, such as vent, fan-light or like windows which are normally out of reach require special window opening and closing mechanisms by which the window may be remotely opened or closed. In an industrial application such as a factory or warehouse such a mechanism may consist of a system of shafts, worms, gears and the like for remotely opening and closing one or more windows but such industrial mechanisms are generally not aesthetically suitable for domestic or office (commercial) applications for aesthetic reasons. While in domestic or commercial situations windows are generally not so highly positioned, nonetheless it may be desirable to be able to remotely operate conventional fan-light or awning windows which are situated at around head height, typically above a fixed pane or another lower awning or casement window. SUMMARY OF INVENTION The present invention provides an improved or at least alternative form of window opening and closing device which is particularly but not exclusively suitable for high mounted windows particularly in such domestic and commercial applications. In broad terms the invention may be said to comprise a window opening and closing device comprising a housing adapted to be mounted to a window sill or window frame or integrally formed as part of a window sill or frame, two flexible coil arms extending from within the housing to be connected at their outer ends to a window sash, and an extension and retraction mechanism within the housing comprising at least one worm gear and means on the inner ends of the flexible coil arms engaging the worm gear(s) so that on rotation of the worm gear(s) one way or the other the flexible coil arms are extended from or retracted into the housing. In one form of the window opening and closing device the extension and retraction mechanism comprises two worm gears and the inner end of each of the flexible coil arms includes a runner means which engages one of the worm gears so that operation of the device to rotate the worm gears causes the flexible coil arms to be extended or retracted from the housing. In another form of the window opening and closing device the extension and retraction mechanism comprises a single worm gear and runner means on the inner ends of each flexible coil arm engage the single worm gear such that as the single worm gear is rotated one way or the other the flexible coil arms are extended or retracted from the housing. The single worm gear may carry two gear spirals of opposite hands on a common part of the worm gear, or the single worm gear may carry two gear spirals of opposite hands on different parts of the single worm gear. Window opening and closing devices of the invention may include an electric motor such as a stepper motor, connected directly or indirectly to the worm gear(s) for electric operation of the device and/ or be manually operated by a cord extending around a pulley attached directly or indirectly to the worm gear(s) or a winding handle coupled to the worm gear(s), for manual operation of the device. BRIEF DESCRIPTION OF DRAWINGS Preferred forms of window opening and closing devices of the invention are illustrated in the accompanying drawings, by way of example, wherein: Figure 1 is a view of a window from the inside having a preferred form opening and closing device of the invention fitted to the window, to a transverse member of the window frame below a sash opening, Figure 2 is a view of a preferred form opening and closing device from the exterior and removed from a window, Figure 3 is a view of the device from one end in the direction of arrow A in Figure 2, with parts of the extension and retraction mechanism, shown in more detail in Figure 4, shown in phantom outline in Figure 3, Figure 4 is a view of a first preferred form device from the inside of the housing showing the inner ends of the two flexible coil arms and the two worm gears of the extension and retraction mechanism within the housing, Figure 5 is a view of a second preferred form device from one end, with parts of the extension and retraction mechanism shown in more detail in Figure 6 shown in phantom outline in Figure 5, Figure 6 is a view of the second preferred form device from the inside of the housing showing the inner ends of the two flexible coil arms and the single worm gear of the extension and retraction mechanism within the housing, Figure 7 is a view of one end of the preferred form device of Figures 5 and 6 from the inside of the housing showing a motor housing containing an electric motor for operation of the device, at one end of the device (Figure 7 shows a cover plate over the extension and retraction mechanism within the housing of the device), Figure 8 is a view of the motor housing from one end with parts shown in phantom outline, Figure 9 is a view of a third preferred form device from one end with parts of the extension and retraction mechanism shown in more detail in Figure 10 shown in phantom outline in Figure 9, Figure 10 is a view of the third preferred form device from the inside of the housing showing the inner ends of the two flexible coil arms and the single worm gear of the extension and retraction mechanism within the housing, Figure 1 1 is a view of the device from one end showing a winding handle for manual operation of the device, with parts shown in phantom outline, and Figure 12 is a electrical block diagram of an electrical control system for an electric stepper motor drive system for window opening and closing devices of the invention. DETAILED DESCRIPTION OF PREFERRED FORMS The preferred form device shown in Figures 1 and 2 comprises a longitudinally extending housing 1 which may be plastic moulded for example, which is adapted to be mounted to an existing window frame as shown, to a transverse frame member of the window frame immediately beneath a sash opening. The device could however be integrally formed in a transverse member of a window frame at manufacture. The device comprises two flexible coil arms 2 which extend from the housing 1 and are connected at their outer ends to the window sash via fittings 3 carried at the outer ends of the flexible coil arms 2, as shown. Within the housing 1 is contained an extension and retraction mechanism including a worm gear or two worm gears, which on operation of the device rotate and are engaged by runners at the inner ends of the flexible coil arms 2, so that rotation of the worm gear(s) will extend or retract the flexible coil arms from the housing, to open or close the window sash. In the preferred form the housing 1 includes parts la and lb from which the flexible coil arms project and extend to the window sash. In an alternative configuration the preferred form device or other form of device utilising the principle of the invention may be fixed or integrally formed in an upright part of a window frame, for example for opening a casement or side-hung window, or in a window sill. The device may be operated by an electric motor or manually or both. The preferred form device shown in Figures 1 and 2 includes an electric stepper motor within a motor housing lc at one end of the housing as shown in Figures 1 and 2. The motor (also shown in Figures 7 and 8) is connected directly or via small step down gears to the worm gear(s) of the extension and retraction mechanism within the housing 1. The motor may be operated by a control positioned lower on the window frame or sill and hard wired to the motor, or alternatively by a hand held infrared or radio frequency remote control. The device may alternatively or additionally be operated by a cord which extends around a pulley connected directly or indirectly to the worm gear(s) (see Figure 7 in particular) or a winding handle which is geared to drive the worm gear(s) (see Figure 11). Figures 3 and 4 show the extension and retraction mechanism of one preferred form of the invention. Two worm gears 40 are mounted within the housing. The worm gears are geared together by gears 41. In this form the two worm gears 40 have gear spirals of the same hand and contra-rotate in operation of the device. Shaft 42 extends from the housing to an electric drive motor or cord and pulley manual arrangement, as will be further described, from one of the worm gears, so that rotation of the shaft 42 will rotate one of the worm gears and contra-rotate the other worm gear through gears 41. The inner end of each flexible coil arm 2 includes a runner 43 with teeth which engage the worm gears as shown. The arrangement is such that rotation of the worm gears one way or the other causes movement of the runners 43 along the worm gears, the direction of movement of the runners 43 depending on the direction of rotation of the worm gears 40, to extend or retract the flexible coil arms 2 and open or close the window sash. In the preferred form shown in the drawings the arrangement of the worm gears 40 and runners 43 is such that when the window sash is closed and the flexible coil arms are fully retracted into the housing, one of the runners 43 is at one end of one of the worm gears 40 while the other runner 43 is at the opposite end of the other worm gear. Operation of the device to extend the flexible coil arms 2 and open the window sash causes the worm gears 40 to rotate such that the runners 43 move towards each other. When the device is operated to close the window sash, the runners 43 move in the opposite direction, to withdraw the flexible coil arms into the housing. In an alternative configuration still using two worm gears the runners 43 or similar may move in opposite directions to those described above as the flexible coil arms are extended or retracted. It is also not necessary that the two worm gears 40 be geared together as in an alternative arrangement each of the worm gears may be driven separately but at the same speed by an electric motor or manual winding mechanism. Referring still to Figures 3 and 4, the lower flexible coil arm extends longitudinally within the housing 1 of the device adjacent one of the worm gears 40 and then through a first smooth curve or bend to extend upwardly at an angle to the worm gears, and then through a second smooth curve or bend through a passage in the part la which guides the bend in the flexible coil arm, from the housing to the window sash. The other flexible coil arm extends from runner 43 adjacent the other worm gear and between guide wheels 45 which ensure that the arm passes through a smooth curve, again to extend upwardly at an angle to the worm gears, and then through a second curve or bend through the other part lb and from the housing. At their outer ends the flexible coil arms carry fittings 3 for attaching the flexible coil arms to the window sash. A tensioning wire 46 extends within each flexible coil arm 2 from the fitting 3 on the outer end of the flexible coil arms through the arms to the inner end of the arms. In the preferred form the tensioning wire extends, at the inner ends of the arms, through the runners 43 in each arm, to a swage 47 as shown. The tensioning wires strengthen the flexible coil arms against force in tension along the length of the arm, such as force applied by wind tending to further open a partly open window sash, or against forced opening of a closed window sash, for example by levering between the window sash and window frame. Figures 5 and 6 show another preferred form of extension and retraction mechanism. In this form a single worm gear 60 carries two spirals of opposite hands on a common part of the worm gear as shown. Runners 63 on the inner end of each of the flexible coil arms engage the worm gear 60 from above and below as shown. The teeth on each of the runners 63 are oriented to engage different spirals on the worm gear 60 so that rotation of the single worm gear will cause the top runner 63 to move in one direction and the bottom runner to move in the opposite direction. When the device is operated to extend the flexible coil arms and open a window sash, the worm gear 60 rotates in a direction such that the runners move towards each other along the worm gear, towards the centre of the worm gear. When the device is operated to withdraw the flexible coil arms and close the window sash, the runners 63 move away from each other along the worm gear. The worm gear 60 may be driven as before, by an electric motor or manual means. The flexible coil arms 2 are the same as before, again preferably including an internal tensioning wire, which may pass through the runners 63 to swages 67. In this form the upper flexible coil arm passes through a guide passage 68 moulded on the interior of the housing 1 as shown, rather than through rotating guides 45 as in Figure 4. Figures 9 and 10 show a third preferred form device. In this form a single worm gear 100 carries two gear spirals 100a and 100b of opposite hands on different parts of the single worm gear. The flexible coil arms again comprise runners 103 on the inner ends thereof, one of which engages each of the gear spirals 100a and 100b. The arrangement is such that rotation of the worm gear 100 in one direction will cause the runners 103 to move away from each other and extend the flexible coil arms, while rotation of the worm gear in the other direction will cause the runners to move towards each other and withdraw the flexible coil arms, to close a window sash. Again the flexible coil arms 2 preferably each include an internal tensioning wire from the outer end within the interior of the arms, through the runners 103 to swages 107. As stated the window opening and closing devices of the invention may be operated by an electric motor or manually or both. Figures 7 and 8 show an electric stepper motor 70 within a housing lc mounted adjacent and connected to one end of the device (see Figures 1 and 2). The electric motor may be mains powered or more preferably is a low voltage motor such as a 12 volt motor which is powered from the mains via a small transformer, or may alternatively be powered by a battery pack. The motor may be connected to the worm gear(s) via step down gears 80. The electric motor may be operated by a control 5 (see Figure 1) positioned lower on the window frame or sill and hard wired to the motor, or alternatively by a hand held infrared or radio frequency remote control. An electric motor so positioned may be fitted to any of the forms of the window opening and closing device described. Alternatively an electric motor may be provided in any other position in relation to the worm gear(s) and connected to drive the worm gear(s) . Preferably the motor is a low voltage stepper motor. An electronics control system associated with the device may be arranged to automatically close the window at a certain time of the day or night if the window is open, having an associated rain sensor, and be arranged to automatically close the window in the event of rain, etc. Sensors may also or alternatively be triggered, for example, by light, or temperature. The device may operate for example to close the windows with darkness, rain or low temperatures and operate to open the windows with daylight, dryness or warm temperatures. In the preferred form shown in Figures 7 and 8 a pulley 75 is mounted about the output shaft of the stepper motor 70 (or at some other suitable position) and a cord 76 extends around the pulley. The cord may optionally be contained within a small compartment behind a door in the motor housing lc so that if for any reason the motor fails or is without power in a power cut for example, the cord may be withdrawn and the window closed (or opened) manually. Other versions of the device may not have a motor and may be normally operated by such a pulley and cord system. Figure 11 shows an arrangement of a winding handle 110 which may be used to open or close the window, by rotating the winding handle in one or other directions. The handle is carried by a shaft 1 11 which on its inner end within the housing carries a bevel gear 112 which engages another bevel gear connected to the worm gear(s) within the housing, so that rotation of the winding handle will rotate the worm gears in one direction, and rotation of the handle in the other direction will rotate the worm gears in the other direction. Preferably the shape of the housing is such that the device (if fitted separately to the window frame) blends into the window frame as unobtrusively as possible. In designing the shape of the housing parts for any particular window profile, ideally the angles and profile of the housing part(s) should follow or be sympathetic to the profile of the window frame. It is also within the scope of the invention for the flexible coil arms to turn additional times e.g. by providing further guide wheels such as those 45 or passages in the housing, the flexible arms could extend over a relatively long distance within the window frame or beneath suitable covers pass horizontally along the window frame, turn to pass vertically downwardly, turn to pass horizontally again, and then turn to pass a final run vertically to the operating handle or equivalent. Figure 12 is a block schematic diagram of an electronic control system for a stepper motor drive system for window opening and closing devices of the invention. Motor 120 is a low voltage (typically 12 volts) stepper motor. The system may be set to either manual operation, in which a user can operate the stepper motor to open or close the device using an open or close button, or automatic operation, in which closing or opening of the device is controlled by a timer or is triggered by a light, rain or temperature sensor for example. In manual mode the open and close buttons may be configured such that pressing the open button will drive the stepper motor only while the button is depressed and close the device only while the close button is depressed, or fully open the device or open the device to a preset extent when the open button is touched and close the device fully when the close button is depressed. Motor 120 has an associated stepper motor drive electronics 121. Open button 122 and close button 123 provide inputs to R/S flip flop (memory) 124 and control the programmable pulse counter 125. Input pulses to the pulse counter are provided by oscillator 126. The programmable pulse counter 125 in conjunction with oscillator 126, controlled by the open or close buttons 122/ 123 through flip flop 124, generates a pre-selected number of pulses (as determined by the position of rotary switch 128) to the stepper motor drive 121. Stepper motors require discrete pulse sequences on their input wires to cause them to rotate and the speed of rotation is determined by the frequency or pulse rate of the driving pulse sequence. The degree to which the stepper motor opens or closes the device is controlled by the length of the pulse sequence to the stepper motor drive 121. Oscillator 127 provides single pulses to the stepper motor drive circuit 121 for manual operation of the device. Temperature controller 129 having an associated temperature sensor 130 is an example of a sensor initiating automatic operation. The output of the temperature controller is provided to flip flop 124 to cause the stepper motor to operate to open or close the device dependent on temperature. Alterations and modifications as will be obvious to those skilled in the art are intended to be incorporated within the scope hereof as defined in the accompanying claims.

Claims: CLAIMS: 1. A window opening and closing device comprising a housing adapted to be mounted to a window sill or window frame or integrally formed as part of a window sill or frame, two flexible coil arms extending from within the housing to be connected at their outer ends to a window sash, and an extension and retraction mechanism within the housing comprising at least one worm gear and means on the inner ends of the flexible coil arms engaging the worm gear(s) so that on rotation of the worm gear(s) one way or the other the flexible coil arms are extended from or retracted into the housing. 2. A window opening and closing device according to claim 1 wherein the extension and retraction mechanism comprises two worm gears and the inner end of each of the flexible coil arms includes a runner means which engages one of the worm gears so that operation of the device to rotate the worm gears causes the flexible coil arms to be extended or retracted from the housing (Figure 4) . 3. A window opening and closing device according to claim 2 wherein the two worm gears are of the same hand and runner means on the inner end of one flexible coil arm engages one end of one of the worm gears and runner means on the inner end of the other flexible coil arm engages the opposite end of the other worm gear when the flexible coil arms are retracted, and operation of the device to extend the arms causes the runner means to move along their respective worm gears towards each other (Figure 4). 4. A window opening and closing device according to claim 3 wherein the worm gears are geared together so that rotation of one of the worm gears causes the other worm gear to rotate in the opposite direction (Figure 4) . 5. A window opening and closing device according to claim 1 wherein the extension and retraction mechanism comprises a single worm gear and runner means on the inner ends of each flexible coil arm engage the single worm gear such that as the single worm gear is rotated one way or the other the flexible coil arms are extended or retracted from the housing (Figures 6 and 9) . 6. A window opening and closing device according to claim 5 wherein the single worm gear carries two gear spirals of opposite hands on a common part of the worm gear and the inner end of one flexible coil arm includes runner means which engages one of said gear spirals and the inner end of the other flexible coil arm includes a runner means which engages the other of said gear spirals (Figure 6). 7. A window opening and closing device according to claim 5 wherein the single worm gear carries two gear spirals of opposite hands on different parts of the single worm gear and the inner end of one flexible coil arm includes runner means which engages one of said gear spirals and the inner end of the other flexible coil arm includes runner means which engages the other of said gear spirals (Figure 9). 8. A window opening and closing device according to any one of the preceding claims including a tensioning wire extending within each flexible coil arm from the inner ends to the outer ends thereof. 9. A window opening and closing device according to any one of the preceding claims including a winding handle coupled directly or indirectly to the worm gear(s) for manual operation of the device. 10. A window opening and closing device according to any one of the preceding claims including a cord extending around a pulley attached directly or indirectly to the worm gear(s) for manual operation of the device. 11. A window opening and closing device according to any one of the preceding claims including an electric motor connected directly or indirectly to the worm gear(s) for electric operation of the device. 12. A window opening and closing device according to claim 1 1 wherein said electric motor is a stepper motor. 13. A window opening and closing device according to claim 12 including an electronics drive system for the stepper motor which enables operation of the stepper motor to open or close the device while an open or close control is operated by a user and/ or automatic closing or opening of the device initiated by a signal from a moisture, light, or temperature sensor. 14. A window opening and closing device according to either claim 12 or claim 13 including an electronics drive system for the stepper motor, comprising an oscillator and a pulse counter to generate a pulse train as a control signal to operate the stepper motor dependent on the length of the pulse train. 15. A window opening and closing device according to any one of the preceding claims wherein said housing is a longitudinally extending housing adapted to be mounted to a transverse member of a window frame immediately below a sash opening or said housing is integrally formed as part of a transverse member of a window frame immediately below a sash opening, and said worm gear(s) extend longitudinally within the housing and transversely of the window frame when the device is in position, and the flexible coil arms extend from within the housing parallel to the worm gear(s), through a first bend to extend upwardly at an angle to the worm gear(s), and through a second bend to extend from the housing at an angle to the transverse member of the window frame to connect to the window sash.

Inventors: DAVIS RONALD PERCIVAL, DAVIS, RONALD, PERCIVAL
Applicants: DAVIS RONALD PERCIVAL, DAVIS, RONALD, PERCIVAL
Application year: 1999
Main classification: E05F11
IPC codes: E05F11, E05F15