This invention relates to movable barrier operators and, more specifically, devices and methods for determining one or more properties of a movable barrier.
Movable barrier operators may be used to control access to areas by moving movable barriers between different positions. Movable barrier operators may estimate properties of the movable barrier such as position and speed by measuring, or deriving from a transmission of the movable barrier operator, the position and speed of an output of the movable barrier operator. However, the estimated properties of the movable barrier may diverge from the actual properties of the movable barrier due to changes in mechanical advantage throughout the path of the movable barrier.
For example, a jackshaft-style movable barrier operator may be installed in a warehouse or garage to control the position of a movable door. The jackshaft operator generally includes an output shaft connected to a counterweight shaft with a torsion spring that lifts most of the weight of the door. To control the position of the door, the jackshaft operator has a drum mounted on the shaft and a cable connected at one end to the drum and at an opposite end to the door. The jackshaft operator can rotate the drum to either wind up or pay out the cable from the drum and generate movement of the door.
The drum of a jackshaft operator may be conical so that a radial distance between the counterweight shaft and the drum surface portion where the cable is being wound up on or paid out from the drum changes as the cable is wound up or paid out. A conical drum may be advantageous in certain applications to provide a different moment arm for the jackshaft operator at different points in the door travel, e.g., the radial distance (and corresponding moment arm) is relatively small at the beginning of door travel when the door is at its heaviest and gradually becomes larger as the door gets lighter toward the end of the door travel. This constantly changing radius makes determining the position of the door based on the position of the output shaft difficult because the distance the door moves with a given amount of shaft rotation changes as the radial distance between the shaft and the drum surface portion (where the cable is being wound up or paid out) varies. Further, the constantly changing radius makes determining the speed of the door based on the speed of the jackshaft operator output shaft difficult because a given speed of rotation of the drum will produce a different speed of the door depending on the position of the door along its path.
Another problem with jackshaft operators is that drums come in a number of different shapes and profiles that allow an installer to select a drum best suited for the barrier and rail system of a particular application. However, from the perspective of a movable barrier operator manufacturer, the shape and profile of a drum that will ultimately be selected by an installer for a particular application is somewhat unknown. Thus, the ability of the movable barrier operator manufacturer to tailor the jackshaft operator to the drum is difficult and the jackshaft operator's understanding of the actual operation of the barrier is therefore less than optimal in some installations. Although the above discussion highlights jackshaft-style operators, the difficulty with estimating the position, speed, or other properties of a movable barrier is equally challenging for other types of movable barrier operators such as trolley style operators.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions and/or relative positioning of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of various embodiments of the present invention. Also, common but well-understood elements that are useful or necessary in a commercially feasible embodiment are often not depicted in order to facilitate a less obstructed view of these various embodiments. It will further be appreciated that certain actions and/or steps may be described or depicted in a particular order of occurrence while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used herein have the ordinary technical meaning as is accorded to such terms and expressions by persons skilled in the technical field as set forth above except where different specific meanings have otherwise been set forth herein.
Generally speaking and pursuant to these various embodiments, an apparatus is provided for use with a movable barrier operator having a rotatable drive configured to rotate and cause an elongate member having a length to be wound up on and paid out from the rotatable drive and produce movement of a movable barrier connected to the elongate member. The apparatus has a base portion configured to be secured to a mounting surface and a sensor configured to interface with the elongate member. The sensor is configured to measure one or more characteristics of the elongate member based on movement of the elongate member along the length thereof as the elongate member moves from being wound up on or paid out from the rotatable drive. The one or more characteristics can include the position, velocity, and/or direction of movement of the elongate member, which the movable barrier operator can use to estimate the corresponding position, velocity, and/or direction of movement of the movable barrier. Further, the apparatus can measure the one or more characteristics of the elongate member independently of the behavior of the rotatable drive of the movable barrier operator. In this manner, the information from the apparatus may combined with measurements from the rotatable drive of the movable barrier operator to provide a more accurate estimate of one or more properties of the movable barrier. In one form, the sensor is further configured to measure tension of the elongate member based upon movement of the elongate member in a direction transverse to the movement of the elongate member along the length thereof. This permits the apparatus to both measure the one or more characteristics of the elongate member and provide information regarding the tension of the elongate member, such as the occurrence of a loss-of-tension event, in one cost-effective device.
The sensor may also comprise a rotatable portion configured to contact the elongate member and be rotated with movement of the elongate member in a direction along the length of the elongate member. The sensor is configured to measure the one of more characteristics of the elongate member based at least in part upon rotation of the rotatable portion. By measuring the rotation of the rotatable portion caused by the elongate member, the apparatus can provide direct measurement of the one or more characteristics of the elongate member to the movable barrier operator using an easy to install interface between the rotatable portion and the elongate member.
An apparatus is also provided including a movable barrier operator configured to move a driven member in a forward direction for moving a movable barrier toward a first position and in a reverse direction for moving the movable barrier toward a second position. The apparatus has a device with a detection portion configured to sense tension and at least one other characteristic of the driven member and a signaling portion configured to generate a signal in response to sensing the at least one characteristic of the driven member. The apparatus further includes a movable barrier operator controller configured to determine one or more properties of the movable barrier based at least in part upon the signal from the signaling portion of the device. Utilizing the signal from the signaling portion of the device, the movable barrier operator controller can make a more accurate determination of the one or more properties of the movable barrier than by estimating the one or more properties of the movable barrier based solely upon the position or speed of a transmission of the movable barrier operator, as in some prior approaches.
In another aspect, a method of operating a movable barrier operator is provided herein. The method includes moving a driven member in a forward direction, measuring tension and at least one other characteristic of a driven member, determining the position of a movable barrier based on the characteristic of the driven member, and sensing a change in the tension of the driven member as the driven member moves in the forward direction. The method further includes indicating that the position of the movable barrier determined from the characteristic of the driven member may be compromised in response to sensing the change in tension of the driven member. One application of this approach is in the event the movable barrier strikes an object while closing. The post-strike position of the movable barrier determined from the characteristic of the driven member could be flagged or otherwise indicated as possibly being compromised due to the collision. Further, the movable barrier may indicate a service call should be made to an authorized repair service or may initiate contact with a repair service on its own, such as by sending an error report to a preselected repair service.
Referring now to the drawings and, in particular, to
The cables 24, 26 each have a pair of opposed ends, with one end connected to a respective one of the drums 20, 22 and the other end connected to the door 12. Winding the cables 24, 26 onto the drums 20, 22 moves the door 12 toward an open position and paying out the cables 24, 26 from the drums 20, 22 moves the door 12 toward the closed position. In the illustrated example, the movable barrier operator 14 is a jackshaft-style operator having a jack shaft 30 connected to a counterweight shaft 32 (see
With reference to
The elongate member sensor device 40 has an idler member 70 with a distal portion 72 connected to the sensor portion 50 and a proximal portion 74 connected via a pivot connection 76 to the base portion 42. The pivot connection 76 has a torsion spring that biases the idler member 70 and spool 54 connected thereto toward the mounting surface 44 to keep the rotatable spool 54 engaged and in contact with the cable 24, as shown in
Eventually, the inward movement of the idler member 70 triggers a switch to indicate a change in tension of the cable 24, as shown in
The signaling portion 90 of the sensor device 40 is configured to transmit information regarding the one or more characteristics measured from the cable 24 to the movable barrier operator 14, as shown in
With reference to
Another example of the sensor portion 50 is shown in
The sensor portion 50 of the elongate member sensor device 40 may interface with the cable 24 in a number of different ways. In one approach, the interface is a frictional engagement between an outer surface of the cable 24 and a cylindrical surface 140 of the spool 54, as shown in
In some applications, the movable barrier operator 14 may be connected to a drum 160 having a configuration as shown in
Similarly, as illustrated in
A simplified schematic view of a portion of the movable barrier operator system 10 is shown in
With reference to
The method further includes monitoring 304 the rotatable drive 16 of the movable barrier operator 14. Monitoring 304 the rotatable drive 16 is performed using the movable barrier operator drive sensor 202. As discussed above, the drive sensor 202 is configured to measure at least one of the position, direction of movement, and speed of the rotatable drive 16. For example, with reference to
Next, one or more properties of the door 12 are estimated 306 based at least in part on the monitoring 304 of the rotatable drive 16. The movable barrier operator controller 200 preferably performs the estimating 306 to provide a generally self-contained and easy-to-install system. In other forms, the estimating 306 may be performed locally such as by communicating with a control system generally at the same geographic location as the movable barrier, or could be performed off-site such as by a remote computer at a movable barrier operator manufacturer.
The estimating 306 can include estimating position, velocity, direction of movement, and/or acceleration of the door 12 based at least in part on the monitoring of the rotatable drive 16 of the movable barrier 14. For example, the portions of the drums 20, 22 about which the cables 24, 26 are wound may be approximated as having an average radius of three inches. If the sensor 202 detects that the jackshaft 30 has rotated one full revolution, which produces a corresponding full revolution of the drums 20, 22, the movable barrier operator 200 could estimate the distance the door 12 traveled by computing:
TravelDoor=2×Π×RAverageDrumRadius
The controller 200 would therefore estimate the door 12 had traveled approximately 18.85 inches in response to one rotation of the jackshaft 30. Although the foregoing example is relatively simple, it will be appreciated that estimating properties of the door 12 based upon measurements from the jackshaft 30 can present problems in terms of changing geometries due to operation of the movable barrier operator 14. This difficulty is heightened with irregularly shaped drums (e.g., drums 160 and 170 in
The estimation 306 of the one or more properties of the door 12 can be enhanced by interfacing 307 the sensor device 40 with the cable 24 (see
Next, the movable barrier operator controller 200 measures 308 one or more characteristics of the cable 24 using the sensor portion 50 of the sensor device 40. The one or more characteristics measured can include position, velocity, direction of movement, acceleration, and/or tension of the cable 24. As discussed in greater detail below, the interfacing 307 and measuring 308 provides a second source of information regarding the position of the door 12 and can be used to supplement the estimation 306.
Using the measured one or more characteristics of the cable 24, the movable barrier operator controller 200 can estimate 310 one or more properties of the door 12. The estimation 310 is preferably independent of the estimation 306 and may, in some instances, be more accurate because the mechanical relationships underlying the estimation 310 generally do not change with movement of the door 12 along its path of travel. Stated differently, the radius of the spool 54 of the sensor device 40 is fixed such that movement of the cable 24 in direction 52 along the length of the cable 24 produces a generally constant, proportional amount of rotation of the spool 54 that can be sensed by the optical interrupter detection device 100 throughout the range of movement of the door 12 (see
The movable barrier operator controller 200 determines 312 an enhanced estimate of the one or more properties of the door 12 based upon the estimates obtained at 306, 310. Determining 312 the enhanced estimate can include resolving differences, if any, of the estimates 306 and 310. For example, the estimate 306 of the one or more properties of the door 12 may be more accurate at the beginning of the travel of the door 12, such as when it opens, and the accuracy of the estimate 306 may decrease as the door travels toward the closed position (such as due to changes in drum profile). To account for this decrease in accuracy, the movable barrier operator controller 200 may increase the formulaic weight given to the estimate 310 and decrease the formulaic weight given to the estimate 306 as the door 12 travels toward the closed position.
Next, the movable barrier operator controller 200 may adjust 314 the operation of the movable barrier operator 14 based on the enhanced estimate 312 of the one or more properties of the door 12. For example, if the property of the door 12 being measured is velocity, the movable barrier operator controller 200 may reduce the velocity of the rotatable drive 16 in the event that the estimated velocity of the door 12 exceeds a desired velocity at a particular location of the door 12 along its travel. This feedback-based adjustment allows the movable barrier operator controller 200 to provide a constant velocity of the door 12 along its travel or provide a desired velocity profile of the door 12 along its travel, such as a simple slow start/stop or a full variable speed profile such as a bell curve. In other applications, the method 300 may not utilize the movable barrier operator drive sensor 202 and may instead rely solely upon the elongate member sensor device 40 and steps 308, 310, 312, and 314.
With reference to
Initially, the movable barrier operator controller 200 operates 402 the rotatable drive 16 of the movable barrier operator 14. For example, the rotatable drive 16 can be operated to turn the drum 20 in direction 430, pay out the cable 24 from the drum 20 in direction 432, and move the door 12 from the open position toward the closed position, as shown in
The movable barrier operator controller 200 measures 404 tension and at least one other characteristic of the cable 24, such as position, velocity, direction of movement, and/or acceleration, when the door 12 is moving toward the closed position. In one approach, measurement 404 includes sensing the tension in the cable 24 by detecting the position of the switch 79 and sensing the velocity of the cable 24 using the optical interrupter detection device 100 of the sensor portion 50.
Next, the movable barrier operator controller 200 estimates 406 one or more properties of the movable barrier, such as a position, velocity, direction of movement, and/or acceleration of the door 12. The estimation 406 can be based solely on information from the measurement 404 of the cable 24, or can utilize information from both the movable barrier operator 14 and the cable 24 in a manner similar to providing the enhanced estimate 312 in method 300. In another form, the estimation 406 could simply receive the enhanced estimate 312 from the method 300 if method 300 is being performed concurrently.
The movable barrier operator controller 200 may sense 408 a change in tension of the cable 24, such as when the door 12 strikes an object. With reference to
In response to sensing 408 the change in tension of the cable 24, the movable barrier operator controller 200 can cause the movable barrier operator 14 to rotate the drum 20 in a reverse direction 440 to pull the cable 24 upward in direction 442, wind the cable 24 onto the drum 20, and pull the door 12 back toward the open position, as shown in
The movable barrier controller 200 then indicates 410 that the one or more properties of the door 12 may be compromised. For example, the movable barrier operator controller 200 may flag the signal from the elongate member sensor device 40 relating to the at least one other characteristic of the cable 24 as potentially being incorrect. This indication or flagging may be useful for the period when the drum 20 is rotating in direction 440 to wind the cable 24 back onto the drum 20 and draw the slack out of the cable 24 after the door 12 has struck the object. The controller 200 may then reduce the weight or importance given to the one or more characteristics determined from the elongate member sensor device 40 until the tension on the cable 24 has been restored and the cable 24 is returned to the operating tension. The resulting return of the cable 24 to its operating tension pivots the idler 70 back to its normal position (see
Next, the movable barrier operator controller 200 measures 412 tension and at least one other characteristic of the cable 24, such as position, velocity, direction of movement, and/or acceleration, after sensing 408 the change in tension of the cable 24. This may include measuring the tension and at least one characteristic of the cable 24 as the cable 24 moves in the reverse direction (such as due to rotation of drum 20 in direction 440). The measuring 412 may also include sensing the tension of the cable 24 reaching a predetermined level, such as tension experienced during normal opening and closing of the door 12. The indication 410 or flag may then be removed once the movable barrier operator controller 200 has determined that the cable 24 is back to operating under normal conditions.
The method 400 further includes estimating 414 one or more properties of the movable barrier 12 post-tension event based on the characteristic measured at 412. In one approach, the estimating 414 is performed in response to the tension in the cable 24 reaching a predetermined level after the tension event, such as the tension being within a range typically experienced by the cable 24 during ordinary operation of the movable barrier operator 14. The estimating 414 permits the movable barrier operator controller 200 to estimate post-tension-event properties of the door 12, such as its position, with the normal weight given to the signal from the elongate member sensor device 40.
Those skilled in the art will recognize that a wide variety of modifications, alterations, and combinations can be made with respect to the above described embodiments without departing from the scope of the invention, and that such modifications, alterations, and combinations are to be viewed as being within the ambit of the inventive concept. This will also be understood to encompass various combinations and permutations of the various components that have been set forth in these teachings.
Number | Name | Date | Kind |
---|---|---|---|
3012520 | Curtis | Dec 1961 | A |
3403474 | Spasoff | Oct 1968 | A |
5310124 | Linari et al. | May 1994 | A |
5743046 | Siegler | Apr 1998 | A |
5826774 | Dell'Aglio et al. | Oct 1998 | A |
6009671 | Sasaki et al. | Jan 2000 | A |
6109017 | Kawatani | Aug 2000 | A |
6782662 | McCartney | Aug 2004 | B2 |
6895355 | Fitzgibbon | May 2005 | B2 |
6956199 | Smith | Oct 2005 | B2 |
7042183 | Fitzgibbon | May 2006 | B2 |
7187150 | Robb | Mar 2007 | B2 |
RE40001 | Siegler | Jan 2008 | E |
8115427 | Banta | Feb 2012 | B2 |
8577627 | Janac et al. | Nov 2013 | B1 |
20020184824 | McCartney et al. | Dec 2002 | A1 |
20040006918 | Fitzgibbon | Jan 2004 | A1 |
20080127560 | Harvey | Jun 2008 | A1 |
20120097783 | Pack et al. | Apr 2012 | A1 |
20120145335 | Panseri et al. | Jun 2012 | A1 |
Entry |
---|
Chamberlain LiftMaster Professional Security + Garage Door Opener Model 3800 Owners Manual (C) 2006. |
Lift-Master, Models 1000 SDR and 2000 SDR Owners Manuals, (C) 1999, 36 pages. See p. 33, elements 9 and 12. |
Number | Date | Country | |
---|---|---|---|
20140250787 A1 | Sep 2014 | US |