Reset mechanism for a panel guide and impact separation system for a sliding door

A sliding door for selectively opening and closing an opening is disclosed. The door is comprised of a door panel having a top, a bottom, a leading edge and a trailing edge. The door panel translates laterally relative to the opening between a closed position and an open position. The door has a guide, a guide follower, and a reset member. The guide is mounted to a mounting surface located between the upper and lower extent of the opening, and comprises a first end disposed proximate the opening and a second end opposite the first end. The guide follower is attached to the door panel and disposed in operable engagement with the guide. The reset member is disposed proximate the second end of the guide. The reset member has a surface that is angularly oriented to facilitate operable engagement and alignment of the guide follower with the guide.

TECHNICAL FIELD

The invention relates to a panel guide and impact separation system for a sliding door, and more particularly to a mechanism for resetting the panel guide after an impact on the sliding door occurs.

BACKGROUND OF THE INVENTION

Sliding doors have been used for many years to secure or isolate various enclosures, including those for cold storage facilities, manufacturing plants, warehouses, garages, and other industrial rooms. Unique to cold storage applications is the need for both door speed and sealing of the doors when closed. Also, unique to cold storage applications is the need for good insulating properties of the door panels themselves. To accommodate both the desirability of fast opening and closing, as well as good insulating properties, door panels can be constructed, for example, from light-weight foam.

Inherent to doors used in connection with cold-storage applications are problems associated with air pressure differentials across opposite faces of the door. These differentials can be caused by a large temperature differential between the cold storage area and the area outside of the cold storage area. These pressure differentials, and others caused for example, by ambient wind, tend to push the door panels inward or outward and away from the walls surrounding the door. Air pressure differentials can also be created by a rapidly actuated panel. Any of these causes can displace a door panel out of its intended plane of travel. This is especially true for relatively light weight panels. This displacement can result in improper positioning of the door when it reaches its closed position, thereby creating problems with proper sealing of the doorway. This can also result in wear and ultimately damage to the hardware associated with the door, including the overhead track.

Others have proposed devices for helping to keep a sliding door panel in proper alignment as it slides. For example, U.S. Pat. No. 6,330,763 issued to Kern et al discloses a ring tethered to a door panel, the ring being slidable along a rope attached to the wall. This rope and ring system is proposed to retain door panels in a position near a wall when sliding. However, it appears that the system proposed in Kern has several deficiencies including that the rope and ring tether (slide restraint and slide) would not, especially with flexible door panels, provide sufficient control over the entire panel except for a portion, such as the trailing edge of the panel, where the slide is tethered to the panel.

Another problem associated with industrial doors is that based upon productivity goals, doors are often hit by forklift trucks or the like which traverse the door opening while the door panels are still partially or completely in a closed position. Accordingly, systems have been proposed for permitting sliding doors to be displaced from their normal plane of travel to accommodate the impact force of the vehicle. Kern et al discloses making the slide of its system frangible. This would require keeping and inventory of spare parts (e.g. slide rings) and down time for the door and traffic while the slide was replaced by maintenance personnel. Kern also discloses the use of flexible tether or rope. This flexible material adds to the lack of control of the panel. It also appears inherent to such flexible ropes that they would work only for a finite distance of displacement upon impact.

The present invention is provided to solve the problems discussed above and other problems, and to provide advantages and aspects not provided by prior doors of this type.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a sliding door panel guide and impact separation system for a sliding door is provided. The door is of the type that is adapted to open and close an opening having an upper and lower extent.

According to another aspect of the invention a mechanism is provided to automatically reset the panel guide follower after an impact. The guide is mounted to a mounting surface located vertically between the upper and lower extent of the opening, and comprises a first end disposed proximate the opening and a second end opposite the first end of the guide. The guide follower is attached to the door panel, and is disposed in operable engagement with the guide. The reset member is disposed proximate the second end of the guide.

According to one aspect of the invention, the reset mechanism has a surface that is angularly oriented to facilitate re-engagement and alignment of the guide follower with the guide after they have become disengaged.

According to another aspect of the present invention, the reset member comprises a first ramp and a second ramp. The first ramp is canted upwardly from the plane of travel of the guide follower. The second ramp angularly and upwardly depends from the top surface of the first ramp and at least partially bisects a top surface of the first ramp.

According to yet another aspect of the present invention, the guide follower is comprised of a retention block and a retention tab. The retention block has a first and second end. A throughway is disposed proximate the first end and provides a pivot point for pivotable connection of the guide follower to a door panel. The retention tab has a first end and a second end. The first end of the retention tab is connected proximate the second end of the retention block. The second end of the retention tab extends generally perpendicular to the retention block and has a channel formed therein proximate a distal end. The channel engages the guide and allows for translation of the guide follower there along.

These and other objects and advantages will be made apparent from the following description of the drawings and detailed description of the invention.

DETAILED DESCRIPTION

The present invention is generally directed to a sliding door10which incorporates a panel guide and impact separation system12(hereinafter, “the guide system12”).FIG. 1shows an automatic bi-parting sliding door10incorporating the guide system12of the present invention. As shown inFIG. 1the door10is generally installed about an opening. “Opening” generally refers to any passage or throughway defined in a general manner by a upper extent, a lower extent and one or more wall edges or other frame-like structures. It is contemplated that opening with which the present invention is employed be a doorway as typically found in a wall of a building or the like. However, the present door can also be installed in a vestibule, which extends away from a doorway. Such vestibules are typically used in applications where it is necessary to minimize the exposure of an interior space to rapid fluctuations in pressure, temperature or other environmental considerations.

The door10with which the guide system12is used generally comprises at least one door panel14. As seen inFIGS. 1, each door panel14has a leading edge13and a trailing edge15, and is adapted to laterally translate along a plane relative to the opening between an open position and a closed position. According to the present invention, the door panels14have a substantially linear opening and closing direction of travel. However, it is contemplated that the travel of the door panels14between the open and closed positions may be slightly non-linear to compensate for seals on the leading edge13of the door10or for other reasons deemed necessary for operation of the door10.

Door panels14used in connection with the present invention may be designed in a variety of sizes and may be constructed from any number of materials. For example, in cold storage applications the door panels14may be made from foam or other materials suitable for maintaining cold and heat differentials on opposed sides of the panels. However, it would be readily understood by those of skill, that the present invention is not limited to use with foam door panels. Instead the present invention may be used with any door panel14of material suitable for a particular application, including wood, metal and various polymeric materials.

Each door panel14should be approximately equal to one-half the width of the opening, and of a height approximately equal to the opening height. With a single sliding door panel design, the door panel14is preferably of the same approximate height and width of the opening. However, the use of greater than two door panels14is also contemplated, and the modification of the presently disclosed invention to accommodate such design variations would naturally be readily understood by those skilled in the art after studying this disclosure, without requiring undue experimentation. Where certain applications may require, it is contemplated by the present invention that the cumulative size of all door panels14in a single application could be significantly less than, or significantly more than the size of the opening.

All remaining discussions will be directed to a single sliding door panel design, but it is understood that such discussion will also be applicable to multi-panel sliding door panels14and the particular design variations mentioned. These types of doors are well known in the art and application of the following discussion to such doors will be readily understood by those skilled in the art.

Typically, a motor16and a drive system18are employed in connection with the doors10described herein. Specifically, as shown inFIG. 1, a motor16is operably coupled to a drive system18for actuating the door panel14between the open and closed positions on an overhead track. For example, the present invention may utilize drive motor16of the type manufactured by SEW-Eurodrive and marketed under the trade name a SEW-Eurodrive MOVIMOT®. However, doors used in connection with the present system may employ any drive motor16that is capable of at least bi-directional, two-speed operation. The door of the present invention may also include a controller19that is in electronic communication with the motor16. The controller19may be any type suitable for use with door assemblies, and which are adapted to control the starting, stopping, speed and direction of the motor16. It is contemplated, however, that the present invention be employed in an application wherein the door panel14is manually moved between the opened and closed positions.

The guide system12of the present invention provides several advantages over prior art systems. For example, the guide system12disclosed herein acts to maintain the actuating door panel14in close proximity to the surrounding wall or mounting surface20throughout substantially its entire path of travel. Additionally, the guide system12is adapted to accommodate and incorporate breakaway features, if so desired. The guide system12also provides a point at which forces applied to semi-flexible door panel14may be concentrated and thus provides predictability in the distribution of the forces in the door. The guide system12and its additional advantages will now be described below in further detail.

As may be seen inFIGS. 1–14, the guide system12generally comprises a guide22and a guide follower24. The guide22is mounted to a mounting surface20located between the upper and lower extent of the opening. As discussed above, the mounting surface20may be a wall surrounding a doorway, or a freestanding surface such as that used in connection with a vestibule. The guide22may be any surface suitable for accommodating generally linear travel of the door panel14between an open and closed position. For example, the guide22may be a plate, a rod, a bar, a u-shaped track, a v-shaped track, or a c-shaped track. The present invention, however, should not be limited to the geometric configurations specifically described or shown herein, as any geometric configuration that provides a generally linear guide path of travel for the door panel14may be employed without departing from the present invention.

As may be seen inFIGS. 2 and 3, the guide follower24is pivotally attached to the door panel14. The guide follower24may be attached to the door panel14by any suitable mechanism that allows for pivoting, including a pin or other fastener. The guide follower24is disposed in operable engagement with the guide22such that, as the door moves between the open and closed positions, the guide follower24translates along at least a portion of the guide22.

According to one embodiment of the present invention shown inFIG. 2-10, the guide follower24is comprised of a retention block26and a retention tab28. The retention block26has a first end26a, a second end26band a throughway30disposed proximate the first end26a. The throughway30provides a pivot point for pivotable connection of the guide follower24to the door panel14. The retention tab28has a first end28aand a second end28b. The first end28aof the retention tab28is connected proximate the second end26bof the retention block26. The second end28bof the retention tab28extends generally perpendicular to the retention block26and has a channel32formed proximate its distal end. The channel32engages the guide22so that there may exist relative sliding between the guide follower24and guide22. Preferably, at least the retention tab28is made from a low friction polymeric material to assist sliding engagement of the guide follower24and the guide22.

The guide follower24is pivotally biased around an axis parallel to the lateral translation of the door, thereby forcing the guide follower24into operable engagement with the guide22. This allows for substantially continuous engagement between the guide follower24and the guide22throughout the entire linear path of travel of the door panel14. The guide follower24can be biased by employing a means for biasing34. As shown inFIGS. 8–10, the means for biasing34is preferably a torsion spring disposed in cooperative engagement with the guide follower24and is secured by a clamp36and stop mechanism38. It is contemplated that other biasing mechanisms may be used to bias the guide follower24, including cams, compression springs, leaf springs, helical springs, elastomeric materials or other suitable biasing mechanisms known to those skilled in the art.

According to the present invention, the guide follower24is adapted to disengage the guide22when sufficient force is applied to the door panel14. If the guide follower24includes a biasing means34, such as is described above, the guide follower24will disengage the guide22when sufficient force is transferred to biasing means34to overcome the force that biases the guide follower24into engagement with the guide22. To assist the guide follower24in releasing from the guide22, the guide follower24may be made from a semi-flexible polymeric material. According to one embodiment of the present invention, at least the second end28bof the retention tab28is sufficiently flexible to permit the guide follower24to disengage the guide22upon receiving an impact in excess of a predetermined force. As shown inFIGS. 5 and 10, the second end28bof the retention tab28may also be tapered. By tapering the second end28bof the retention tab28, less material surrounds the channel32, thus assisting the retention tab28in flexing so that guide follower24may more easily disengage the guide22upon impact to the door panel14.

FIGS. 11–13illustrate another embodiment of a guide follower24′ that may be used in connection with a guide system12′ of the present invention. As shown inFIGS. 11–13, the guide follower24′ comprises a trolley40. The trolley40generally includes a retention block42and a roller assembly block44. The retention block42is attached to the trailing edge15of the door and the roller assembly44is coupled to the retention block42. According to the present invention, the roller assembly block44has at least one roller46operably disposed thereon. In one embodiment shown inFIG. 13, the roller assembly block44has a plurality of rollers46, and at least two of the plurality of rollers46engage the, guide22′ on opposed sides of the guide22′ so that a channel is formed between the rollers46. The rollers46are preferably made from a low friction polymeric material to assist the guide follower24′ in rolling on the guide22′.

The guide follower24′ may also include a resilient material (not shown) disposed between the block and roller assembly. In one embodiment, a tensioning arm48having a pivoting end50and a locking end52is attached to either the retention block42or the roller assembly block44. A clasp adapted to receive the locking end52of the tensioning arm48is attached to the other of the retention block42and the roller assembly block44. According to this configuration, the retention block42and roller assembly block44may be connected one to the other by the tensioning arm48. When the locking end52of the tensioning arm48is fastened to the clasp, the roller assembly block44is drawn closer to the retention block42. The resilient material, however, is of sufficient thickness and resiliency such that when it is compressed, the resilient material creates a resistant force between the retention block42and the roller assembly block44.

The rollers46of this embodiment of the guide follower24′ may be press fit on their respective roller mounts such that when a force in excess of a predetermined force is applied to a door panel14to which this guide follower24′ is connected, the rollers46separate from the trolley40. Alternatively, the guide follower24′ may be configured such that the rollers46remain attached upon application of a predetermined force to the door panel14, but the retention block42separates from the roller assembly block44.

According to another embodiment of the guide system12″ shown inFIG. 14, a magnet56is attached to either the guide follower24″ or the door panel14. A magnet attracter58is attached to the other of the guide follower24″ and the door panel14. The magnet56magnetically engages the attracter58and couples the guide follower24″ to the door panel14. The magnet56is separable from the magnet attracter58upon an impact to the door panel14in excess of a predetermined force, thereby permitting the panel14to separate from the guide follower24″.

As shown inFIGS. 2,3and11, the present invention can include an elongate beam60which is attached to the door panel14between the top and the bottom of the door panel14. A first portion of the elongate beam60extends generally horizontally along a vertical plane of the door panel14. A second portion of the elongate beam60extends away from the leading edge13of the door panel14and beyond the trailing edge15of the door panel14. Thus, the elongate beam60effectively functions as an “outrigger” for the door panel14. The second portion of the elongate beam60operably engages the guide22,22′,22″. It is contemplated that the second portion of the elongate beam60engages the guide22,22′,22″ directly or, as shown inFIGS. 3 and 11, by attaching one of the above described guide followers24,24′,24″ proximate the distal second portion of the elongate beam60. The elongate beam60may have any geometric cross-section without departing from the invention, including for example a cylindrical rod or a rectangular beam. Furthermore, it will be apparent to those of skill in the art that the elongate beam60may be of any size suitable for the application with which the door10is being used.

In one embodiment, the elongate beam60extends across substantially the entire vertical plane of the door panel14. However, it is contemplated by the present invention that the elongate beam60extend across less than the entire vertical plane of the door panel14. The extent to which the elongate beam60extends across the door panel14will be dictated by the specific application with which the invention is being used, as well as by the size, material and construction of the door panel14. It will be readily understood by those of skill in the art, however, that any configuration in which some portion of the beam extends across at least a portion of the vertical plane of the panel, and some portion of the elongate beam60extends beyond the trailing edge15of the door panel14will be suitable for the present invention.

According to one embodiment of the present invention shown inFIGS. 2,3and11, the first portion of the elongate beam60extends through the core of at least a portion of the door panel14and the second portion of the elongate beam60extends out of the trailing edge15of the door panel14. For example, in door systems which employ semi-flexible door panels14such as those formed of foam, the elongate beam60serves to provides stiffness to the door panel14. Accordingly, the door panel14is not only imparted with a degree of stiffness to withstand impact, but the elongate beam60also provides improved stiffness to assist in aligning leading edge13seals or the like during opening and closing of the door panel14.

The elongate beam60, as used in connection with flexible or semi-flexible door panels14, also provides a point at which impact forces may be concentrated. This provides predictability in the distribution of the forces in the door, thereby allowing a reliable breakaway mechanism. Additionally, the elongate beam60acts to ameliorate stress at the connection between the door panel14and the guide system12,12′,12″ by moving the stress point away from the panel edge to the breakaway mechanism associated with the guide system12,12′,12″. In so doing, the elongate beam60provides integrity to the connection of the door panel14to the guide system12,12′,12″. The elongate beam60also reduces damage to the overhead track and minimizes derailment of the door panels14from the overhead tracks.

According to another embodiment of the present invention, the door system further comprises a reset member70. As shown inFIGS. 15 and 16, the reset member70is disposed proximate the second end of the guide22,22′,22″. The reset member70has a surface72that is angularly oriented to facilitate operable engagement and alignment of the guide follower24,24′,24″ with the guide22,22′,22″. In a preferred embodiment, the reset member is adapted for use on the left-hand and right-hand sides of the guide system12,12′,12″.FIGS. 17 and 18depict a left-hand and right-hand reset member70, respectively. Each reset member70comprises a first ramp74and a second ramp76. The first ramp74is canted upwardly from the plane of travel of the guide follower24,24′,24″. The second ramp76angularly and upwardly depends from the surface72of the first ramp74and at least partially bisects the surface of the first ramp. Cooperation between the ramps74,76of the reset member70and the guide system12,12′,12″ facilitates operable engagement of the guide follower24,24′,24″ and the guide22,22′,22″.