The present invention relates, generally, to door control mechanisms and hinge systems for controlling the opening and closing of doors or panels and, more particularly, to door control assemblies for controlling the opening and closing of relatively large and heavy doors closing openings into refrigerated spaces, such as walk-in coolers, refrigerators, food chilling compartments, and the like.
Door opening and closing mechanisms typically include spring mechanisms, or pneumatic or hydraulic piston devices. The mechanisms are mounted either between the door frame and a midsection of the door, or between the door frame and the top of the door. For example, door closers used to return storm doors and screen doors to a closed position generally include a cylindrical tube containing a piston and a rod with an end extending from the free end of the tube. The end of the rod is attached to the door frame and the other end of the tube is attached to the door. As the door is opened, the rod is forced out of the tube, which compresses a spring positioned inside the tube. When the door is released, the spring causes the piston to return to its retracted position in the tube, which places a closing force on the door.
Another common door control mechanism mounts to a top edge of the door and is anchored to the top of the door frame. Door control mechanisms located in this position are typically used for large heavy doors found in office buildings, warehouses, schools, and the like. A large oblong metal casing is mounted to the top of the door. Inside the casing, a spring drives a piston that is, in turn, either pneumatically or mechanically damped to control door speed when the door is closing. Opening the door compresses the spring and stores energy in the spring. Releasing the door allows the spring to extend to its uncompressed position, which asserts a closing force on the door.
Door control mechanisms of the type described above tend to be large and bulky devices that detract from the aesthetic appearance of the door to which they are attached. Further, the typical door control mechanisms are designed to work with heavy mechanical door latches. The mechanical door latches typically require considerable closing force to securely latch the door. Accordingly, the door control devices used with mechanical latches apply a large closing force to satisfy the closing force requirements of the mechanical latch. Further, in many cases, the door control mechanisms described above do not exert any opening force upon the door. Separate mechanical systems are used to open doors automatically in situations where opening assistance is required.
Doors that close openings into refrigerated compartments, such as walk-in coolers, refrigerators, food chilling compartments, and the like, are usually large and heavy doors. Doors of this type are often designed to have a width that is sufficient to allow movement of carts, hand trucks, and other cargo transporting devices into and out of refrigerated compartments. To accommodate the size and weight of refrigerated compartment doors, the door closing mechanisms are proportionately large and designed to apply sufficient force to securely latch the door.
With the development of new light-weight, high R factor insulation, high-strength construction materials, commercial refrigerated compartments can now be built and designed with refined features and improved latching mechanisms. For example, doors for commercial refrigerated compartments can now be latched and sealed with magnetic closures. Additional design refinements include contoured handles and refined hinge systems that, in the past, could only be used on lighter weight, smaller doors.
With the continued refinements in refrigerated compartment construction, more active door control systems have been sought in order to improve the ease of door operation. Needed operational improvements include opening assistance and the ability to park the door in a partially-opened position. Further, desired door operation improvements include the ability to exert a controlled amount of force on the door in a wide variety of opened positions, including fully opened at an open angle of 180°. In addition to operational improvement, a need exists for a more compact door control mechanism that does not detract from the aesthetic appearance of the door.
In accordance with the invention, there is provided, in one aspect, a door control assembly for a door closing an opening into a refrigerated compartment. The door control assembly includes a mounting plate attached to the door and a flange attached to a wall of the refrigerated compartment. The flange includes a platform extending away from the wall and a first ball stud and a first post extend from the platform. A reciprocating arm is coupled to the mounting plate and a second ball stud and a second post extend from the reciprocating arm and are oriented generally perpendicular to the reciprocating arm. A control mechanism is pivotally engaged with the first ball stud at a first end and with the second ball stud at a second end and a cable is coupled to the first post at a first end and to the second post at a second end.
In accordance with another embodiment of the invention there is provided a combination of a door closing an opening into a wall of a refrigerated compartment, a hinge set, and a door control assembly. The door control assembly includes a mounting plate attached to the door and a flange attached to a door frame of the refrigerated compartment. A door control mechanism has a first end attached to the flange and a second end attached to the mounting plate. A cover is attached to the mounting plate and overlies the first end of the door control mechanism. The cover has a canopy cantilevered over the flange and encloses the first end of the door control mechanism against the wall.
In still another embodiment, the invention includes a concealed middle door control assembly that includes a door control mechanism for applying opening and closing force to a door. A mounting plate is positioned behind the control mechanism. The mounting plate has a curved section cantilevered away from the mounting plate. A cover overlies the control mechanism, wherein the cover has a canopy at a first end that cooperates with the curved section to enclose the control mechanism, and wherein the cover is coupled to the mounting plate at a second end.
In yet another embodiment of the invention a refrigerated compartment is provided having a wall and a door positioned within a door frame and closing and opening in the wall. An upper door hinge has a hinge pin displaced a first distance from the wall and a lower door hinge has a hinge pin displaced a second distance from the wall, where the second distance is greater than the first distance. A door control mechanism has a first end attached to the door frame and a second end attached to a midsection of the door. The door control mechanism is configured to exert an opening force when the door is opened by a user and to exert a closing force when the door is closed by a user. A cover conceals the door control mechanism.
In a further embodiment of the invention, a door control assembly is configured to exert an opening and a closing force on a door positioned within a door frame. The door control assembly includes a reciprocating arm coupled to the door and a flange attached to the door frame. A fluidic control mechanism is coupled to the flange at a first end and to the reciprocating arm at a second end and a cable is coupled to the flange at a first end and to the reciprocating arm at a second end.
Door 22 includes a top edge 32, a bottom edge 34, a left edge 36, and a right edge 38. Door handle 24 extends across a face surface 40 of door 22 in a first direction generally parallel with top edge 32 and bottom edge 34. Door handle 24 includes a grip 42 and a handle extension 44 that couples to concealed door control assembly 30. Door 22 also includes an upper door molding 46 and a lower door molding 48. As will subsequently be described, door control assembly 30 provides an opening and closing force on door 22, such that door 22 can be easily opened and closed by a user. Additionally, door control assembly 30 allows door 22 to be parked in a partially open or fully open position to facilitate movement of materials into and out of refrigerated compartment 20. Further, the active control mechanisms of door control assembly 30 are configured so as to be concealed behind a cover that engages handle extension 44. Accordingly, door control assembly 30 provides operating assistance to door 22 while not detracting from the aesthetically-pleasing appearance of door 22. Further, door control assembly 30 can be configured to share common aesthetic design aspects with upper and lower hinges 26 and 28.
A perspective view of door control assembly 30 is illustrated in
A fluidic control mechanism 72 has a first end 74 pivotally engaged with first post 58 and a second end 76 pivotally engaged with second post 64. Door control assembly 30 further includes a cable 78 having a first end 80 coupled to first post 60 and a second end 82 coupled to second post 64. As used herein, the term “pivotally” refers to radial movement in all directions. As will subsequently be described, the fluidic control mechanism and the cable are able to move in more than one plane with respect to the flange and the mounting plate as the door is opened and closed.
In the embodiment illustrated in
Mounting plate 52 contains several portions that interlock or mate with a cover (shown in
Mounting plate 52 has a locking tab 94 located at the opposite end of mounting plate 52 from plate 88. As will subsequently be described, locking tab 94 interlocks with handle extension 44.
Mounting plate 52 also includes an upper bracket 96 and a lower bracket 98. Upper bracket 96 and lower bracket 98 contain receiving channels 100 are configured to receive locking pins in the cover that attaches to mounting plate 52.
A perspective view of reciprocating arm 66 is illustrated in
The operation of door control assembly 30 will now be illustrated through top views and side views of door control assembly 30 in various door open positions. A top view and a side view of door control assembly 30 are illustrated in
When door 22 is in a fully closed position, reciprocating arm 66 leans slightly to the left of vertical. Further, a pivot point 120 (shown by crosshairs in
In a preferred embodiment of the invention, upper and lower hinges 26 and 28 are cam hinges. When door 22 is open, upper and lower hinges 26 and 28 create a slight upward motion of door 22 as they ride on load-bearing cam surfaces. As will subsequently be described, door control assembly 30 is configured to accommodate the camming operation of upper and lower hinges 26 and 28. In the side view of
As shown in the top view of
In accordance with the illustrated embodiment of the invention, piston 72 will exert an opening force on mounting plate 52 and door 22 when the open angle of door 22 is about 90° to about 110° with respect to door frame 50. In this range of door opening movement cable 78 has crossed over center point 120 and remains taut and counterbalances the closing force exerted by piston 72. Also, piston 72 exerts an opening force on door 50. Thus, the action of cable 78 in combination with reciprocating arm 66 provides a net opening force on door 22. When door 22 is open at an angle of about 45°, the pushing force exerted on door 22 by piston 72 is substantially the same as the pulling force exerted on door 22 by cable 78. Also, a door open angle of about 45°, reciprocating arm 66 is in a substantially vertical position with respect to mounting plate 52.
When door 22 is open at an angle of about 90° with respect to door frame 50, door control assembly 30 appears as illustrated in the top view of
A top view and a side view of door control assembly 30 at a door open angle of about 180° are illustrated in
As a result of the camming action of upper and lower hinges 26 and 28, door 22 reaches a maximum vertical displacement at a door open angle of about 100°. In the illustrative embodiment, door 22 is lifted about 7/16 inches relative to its fully-closed position. The vertical displacement is reflected in
A comparison between
A schematic diagram of piston 72 and cable 78 is shown in four different door open positions in
The data presented in Table I shows that the closing torque and net torque have maximum values when the door is closed, which corresponds to a door angle of 0°. The closing torque and net torque gradually diminish as the door open angle increases to 80°. At door open angles of 100° to about 110°, the closing torque and the net torque have negative values. At door open angles of about 120° to about 180°, the closing torque continues to have a negative value but decreases in magnitude, while the net torque becomes positives and increases in value. The opening force required at the door handle is strongest at 0° door open angle and diminishes to a minima between a door open angle of about 80° and about 100°. There is essentially an auto opening force at door open angles of about 80° to about 120°. At door open angles of about 120° to about 180°, the opening force increases to a maxima at door open angles of about 145° to about 160°, then diminishes slightly at a fully open door position corresponding to a door open angle of about 180°.
Those skilled in the art will recognize that door control assembly 30 is configured to produce a precise closing force and opening force on door 22 at various door open angles. The opening force and closing force are balanced relative to one another to provide precise amounts of door open and closing assistance during the travel of door 22 from a fully closed to a fully-open position. By precisely controlling the net force applied to door 22 at various open angles, door open assistance can be generated so that a user does not have to provide all the force necessary to open door 22. Opening assistance is particularly advantageous for the relatively-large doors typically used with refrigerated compartments, such as food chilling compartments and the like. Door control assembly 30 also exerts a closing force on door 22 that assists in providing sufficient force to properly close door 22. In the illustrative embodiment described herein, door control assembly 30 generates a closing force sufficient to allow a magnetic door latch to engage door 22 and hold door 22 in a closed position within door frame 50.
In addition to generating both an opening force and a closing force, door control assembly 30 also enables door 22 to be parked in an open position. In the illustrative embodiment, door 22 can be parked at a door open angle of about 120° or greater. As indicated in Table I, the closing torque and the net torque have approximately equal magnitude but opposite directions at about 120°. Also, the opening force exerted by door control assembly 30 at a door open angle of about 120° has only a small, slightly positive value. Under this combination of applied forces, door 22 can be opened by a user to a door open angle of about 120° or greater and will remain in that position until a user exerts an opening or closing force on door 22.
The particular force values illustrated in Table I represent one embodiment of the invention. Those skilled in the art will recognize that the force values and resultant net torque vectors applied to door 22 can vary depending on, for example, the particular design characteristics of piston 72, the locations of first ball stud 58 and first post 60, the length of reciprocal arm 66, and its distance from flange 54, and the like. Accordingly, the relative force values shown in Table I can vary depending upon the particular design attributes of door control assembly 30. For example, the amount of force applied to door 22 can be increased or decreased depending upon the weight of the door or the particular location of door control assembly 30 on door 22 or the like. Further, where it is not desired that door 22 remain open under any circumstances, door control assembly 30 can be configured to apply a constant closing force on door 22.
In accordance with the illustrated embodiment of the invention, door control assembly 30 includes covering hardware and coupling features that function to both conceal the operative elements of door control assembly 30 and to present an aesthetically-pleasing exterior appearance. Shown in
After attaching cover 124 to mounting plate 52, a cap 136 is positioned in a seat formed by a combination of canopy 130 and plate 88. As illustrated in the front view of
In
A top view of the enclosed door control assembly is illustrated in
Thus, it is apparent that there has been described in accordance with the preferred embodiment of the invention a door control assembly, door, and hinge set that fully meet the advantages set forth above. Although the invention has been described and illustrated with reference to specific illustrative embodiments thereof, it is not intended that the invention be limited to those illustrative embodiments. Those skilled in the art will recognize that variations and modifications can be made without departing from the spirit of the invention. For example, a wide variety of materials can be used to construct the various components of the door control assembly, such as sheet metals, plastics, metallized plastics, and the like. Further, the outward shape and location of the door control assembly can vary depending upon factors, such as the size and weight of the door. It is therefore intended to include within the invention all such variations and modifications that fall within the scope of the appended claims and equivalents thereof.