Door assemblies for ground support tractors
Patent Information
- Application Number
- FR2024009600
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-09-11
- Filing Date
- 2024-09-10
- Publication Date
- 2025-03-14
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Title of the invention: Door assemblies for ground assistance tractors
[0001] TECHNICAL FIELD OF DISCLOSURE
[0002] The present disclosure relates, in general, to door assemblies for ground support tractors and, in particular, to a door assembly for a ground support tractor that has a door with a closure panel that moves from an extended position to a retracted position in response to movement of the door from a closed position to an open position.
[0003] CONTEXT
[0004] Ground handling tractors, also known as airport tugs or aircraft tugs, are designed to transport and handle various types of loads at airports. For example, some ground handling tractors are used to move and tow aircraft on the ground. These ground handling tractors are designed to maneuver aircraft safely and efficiently in and out of gates, hangars, runways, and other areas of the airport. These ground handling tractors are essential for tasks such as pushing aircraft away from the gate, positioning aircraft for departure, and towing aircraft to maintenance or storage areas. Thus, these ground handling tractors ensure that aircraft are properly positioned and ready for takeoff or maintenance, thereby contributing to the smooth operation of the airport.Other ground handling tractors are equipped with specialized attachments, such as cargo loaders or baggage carts, which allow them to efficiently move baggage, cargo containers, and other types of cargo between different areas of the airport, such as the terminal, an aircraft's hold, and airport storage facilities. Thus, these ground handling tractors help streamline the process of loading, transporting, and unloading cargo and baggage.
[0005] Because ground tractors operate in confined spaces and near aircraft, it has been found that opening the doors of a ground tractor can create impact hazards. For example, if the doors of a ground tractor open outward, like a conventional car door, this can create an impact hazard with other vehicles or equipment in an airport baggage hall. Similarly, if the doors of a ground tractor open upward, as is typically the case with a gull-wing or scissor door, this can create an impact hazard with the landing gear. landing of an aircraft. Therefore, it became necessary to have a ground handling tractor with doors that do not create a risk of impact for nearby aircraft when the doors are open.
[0006] SUMMARY
[0007] In a first aspect, the present disclosure relates to a door assembly for a vehicle. The door assembly includes a bottom rail including a ramp and a door slidably received by the bottom rail and movable relative thereto in a first direction between a closed position and an open position. The door includes a main panel and a bottom panel that is movable relative to the main panel in a second direction between an extended position and a retracted position. The ramp is configured to apply a retracting force to the bottom panel that causes the bottom panel to move from the extended position to the retracted position in response to movement of the door from the closed position to the open position.
[0008] In some embodiments, the second direction may be substantially perpendicular to the first direction. In some embodiments, the first direction may be a longitudinal direction and the second direction may be a vertical direction. In some embodiments, the main panel may have inner and outer skins between which the bottom panel may be positioned when the bottom panel is in the retracted position. In some embodiments, the bottom panel may be slidably coupled to an interior surface of one of the inner and outer skins of the main panel. In some embodiments, the ramp may have a slope of between thirty degrees and forty-five degrees, such as a slope of about thirty-five degrees.In some embodiments, the lower panel may have a lifting surface configured to contact the ramp. In such embodiments, the ramp and the lifting surface may have substantially common slopes.
[0009] In a second aspect, the present disclosure relates to a ground support tractor having a wheeled chassis on which a cab is mounted. A door assembly is coupled to the cab. The door assembly includes a bottom rail having a ramp and a door slidably received by the bottom rail and movable in a first direction relative to the cab between a closed position and an open position. The door includes a main panel and a closure panel that is movable relative to the main panel in a second direction between an extended position and a retracted position, the second direction being substantially perpendicular to the first direction. The ramp is configured to apply a retracting force to the closure panel that causes the closure panel to closure to move from the extended position to the retracted position in response to the door moving from the closed position to the open position.
[0010] In some embodiments, the door assembly may include a top rail such that the bottom rail and the top rail limit movement of the door to movement in the first direction relative to the cab. In some embodiments, the door assembly may include a front latch configured to secure the door in the closed position. In some embodiments, the door assembly may include a rear latch configured to secure the door in the open position. In some embodiments, the cab may include a cab floor such that the closure panel has a contacting relationship with the cab floor when the door is in the closed position. In some embodiments, the closure panel may be disposed within the main panel when the closure panel is in the retracted position.In some embodiments, the main panel may include inner and outer skins between which the closure panel may be positioned when the closure panel is in the retracted position. In some embodiments, the door assembly may include a telescopic slide assembly that is coupled between the closure panel and at least one of the inner and outer skins. In such embodiments, the telescopic slide assembly may be a vertically oriented linear telescopic slide assembly. In some embodiments, the closure panel may move from the retracted position to the extended position in response to a gravitational force as the door moves from the open position to the closed position.
[0011] In a third aspect, the present disclosure relates to a ground support tractor having a wheeled chassis with a cab mounted thereon. A door assembly is coupled to the cab. The door assembly includes a bottom rail having a ramp and a door slidably received by the bottom rail and movable in a longitudinal direction relative to the cab between a closed position and an open position. The door includes a main panel and a closure panel that is movable in a vertical direction relative to the main panel between an extended position and a retracted position, the closure panel having a lifting surface. The closure panel is in the extended position when the door is in the closed position. The closure panel is in the retracted position when the door is in the open position.The closing panel moves from the extended position to the retracted position in response to contact between the lifting surface and the ramp as the door moves from the closed position to the open position. The closing panel moves from the retracted position to the extended position as the door moves from the open position to the closed position.
[0012] In some embodiments, the ramp may be configured to apply a retracting force to the closure panel that causes the closure panel to move from the extended position to the retracted position in response to movement of the door from the closed position to the open position. In some embodiments, the closure panel may move from the retracted position to the extended position in response to a gravitational force as the door moves from the open position to the closed position. Brief description of the drawings
[0013] For a more complete understanding of the features and advantages of the present disclosure, reference is now made to the detailed description and to the accompanying figures in which corresponding numbers in the various figures refer to corresponding parts and in which:
[0014] [Fig.l] is a schematic illustration of a ground support tractor towing a cargo container in accordance with embodiments of the present disclosure;
[0015] [Fig.2A] is a schematic illustration of a ground support tractor with selected components removed in accordance with embodiments of the present disclosure;
[0016] [Fig.2B] is a schematic illustration of a ground support tractor with selected components removed in accordance with embodiments of the present disclosure;
[0017] [Fig.3A] is a sequential isometric view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0018] [Fig.3B] is a sequential isometric view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0019] [Fig.3C] is a sequential isometric view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0020] [Fig.3D] is a sequential isometric view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0021] [Fig.4A] is a sequential side view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0022] [Fig.4B] is a sequential side view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0023] [Fig.4C] is a sequential side view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0024] [Fig.4D] is a sequential side view of a ground support tractor illustrating the operation of a door assembly in accordance with embodiments of the present disclosure;
[0025] [Fig.5A] is a schematic illustration showing a door of a ground support tractor in the fully closed position in accordance with embodiments of the present disclosure;
[0026] [Fig.5B] is a schematic illustration showing a door of a ground support tractor in the fully closed position in accordance with embodiments of the present disclosure;
[0027] [Fig.6] is an exploded view of a door and bottom rail of a door assembly for a ground support tractor in accordance with embodiments of the present disclosure;
[0028] [Fig.7] is an exploded view of a door for a ground support tractor in accordance with embodiments of the present disclosure;
[0029] [Fig.8A] is a schematic illustration showing a door of a tractor ground assist in the fully open position in accordance with embodiments of the present disclosure, and.
[0030] [Fig.8B] is a schematic illustration showing a door of a ground support tractor in the fully open position in accordance with embodiments of the present disclosure. DETAILED DESCRIPTION
[0031] Although the manufacture and use of various embodiments of the present disclosure are discussed in detail below, it should be noted that the present disclosure provides numerous applicable inventive concepts, which may be incorporated into a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative and do not limit the scope of the present disclosure. For the sake of clarity, not all features of an actual implementation may be described in this specification. It should, of course, be noted that in developing such an actual embodiment, numerous implementation-specific decisions must be made to achieve the developer's specific goals, such as conformance to system-related constraints and to the activities, which will vary from one implementation to another. Further, it will be understood that such a development effort could be complex and time-consuming, but would nevertheless be a common undertaking for those skilled in the art taking advantage of the present disclosure.
[0032] In the description, reference may be made to the spatial relationships between various components and the spatial orientation of various aspects of components such as the devices are shown in the accompanying drawings. However, as will be recognized by those skilled in the art after a complete reading of this disclosure, the devices, elements, apparatuses and the like described herein may be positioned in any desired orientation. Thus, the use of terms such as "above," "below," "upper," "lower," or other similar terms to describe a spatial relationship between various components or to describe the spatial orientation of aspects of such components should be understood as describing a relative relationship between the components or a spatial orientation of aspects of such components, respectively, as the devices described herein may be oriented in any desired direction.As used herein, the term "coupled" may include direct or indirect coupling by any means, including simple contact or by movable and / or non-movable mechanical connections.
[0033] Referring to [Fig.l] of the drawings, a ground vehicle represented as a ground support tractor is schematically illustrated and generally designated by the number 10. In the illustrated embodiment, the ground support tractor 10 tows a load represented as a cargo container 12 at an airport, for example between the terminal and a cargo hold of an aircraft. The ground support tractor 10 is a wheeled vehicle which has a pair of front steered wheels, the left front wheel 14 being visible, and a pair of rear driven wheels, the left rear wheel 16 being visible.Each of the front wheels of the ground support tractor 10 is positioned in a front wheel well, with the left front wheel well 18 being visible, the front wheel wells being sized to allow rotation of the front wheels therein to control the direction of travel of the ground support tractor 10 when the ground support tractor 10 is in motion. Structural support for the ground support tractor 10 is provided by the frame 20, on or around which the various components of the ground support tractor 10 are assembled (see also [Fig. 2A]). The frame 20 is formed from a plurality of structural members that are interconnected by welds, bolts, and / or other suitable fastening means. The structural members include a plurality of frame members 22 and a plurality of plate members 24 made of metal or metal alloy, such as steel or aluminum.When the front and rear wheels are coupled to it, the chassis can be termed as a 20-wheel chassis.
[0034] In the illustrated embodiments, the ground support tractor 10 includes a battery array 26 including battery packs 26a, 26b that are coupled to a rear portion of the wheeled chassis 20 (see also [Fig. 2B]). The battery array 26 provides the energy necessary to power the movement of the ground support tractor 10 as well as the various electronic components of the ground support tractor 10. The ground support tractor 10 includes a drive train 28 shown to include an electric motor 28a and a transaxle 28b that are operatively coupled to the rear drive wheels of the ground support tractor 10 and receive electrical power from the battery array 26. An electronic motor controller 30 is operatively coupled to the electric motor 28a and provides control functionality for the electric motor 28a.In other embodiments, the powertrain of the ground support tractor 10 may include an internal combustion engine and a transmission. The ground support tractor 10 has a front base plate assembly that forms a cab floor 32. The ground support tractor 10 includes vehicle controls including a steering control device 34a that is operatively coupled to the front wheels and motion control devices 34b shown as pedals for accelerating and stopping the ground support tractor 10 (see also [Fig. 4D]).In the illustrated embodiment, the vehicle controls are shown on the left side of the ground support tractor 10 such that the ground support tractor 10 is configured to have the driver on the left side of the vehicle, thereby defining the left side of the ground support tractor 10 as the driver's side and the right side of the ground support tractor 10 as the passenger's side. In other embodiments, the vehicle controls may be positioned on the right side of a ground support tractor. The ground support tractor 10 has various body panels 36 including, for example, a front body panel 36a, a left side lower body panel 36b, a right side lower body panel 36c, a rear body panel 36d, and a left side upper body panel 36e.One or more of the body panels 36 may be formed integrally or may be interconnected by welds, bolts, and / or other suitable fastening means. Similarly, one or more body panels 36 may be formed from multiple panel members. The body panels 36 are coupled to the wheeled chassis 20 by welds, bolts, and / or other suitable fastening means to provide an external covering for the ground support tractor 10 and protect the various operating components of the ground support tractor 10 disposed therein. The body panels 36 are preferably made of metal or a metal alloy, such as steel or aluminum.
[0035] The ground support tractor 10 includes a cab 38 that is mounted on a wheeled chassis 20 above the cab floor 32 to provide an enclosure for operators of the ground support tractor 10. The ground support tractor 10 includes a driver's side door assembly 40a and a passenger's side door assembly 40b (see also [Fig. 3A]). It is noted that the passenger's side door assembly 40b is substantially similar to the driver's side door assembly 40a, therefore, for efficiency, certain features will only be disclosed with respect to the driver's side door assembly 40a. However, those skilled in the art will fully appreciate an understanding of the passenger's side door assembly 40b based on the disclosure herein of the driver's side door assembly 40a.The driver's side door assembly 40a includes a lower rail 42 having a ramp 44 and a door 46 that is slidably received by the lower rail 42 and movable relative thereto in a fore / aft or longitudinal direction of the ground support tractor 10 between a closed position and an open position. The door 46 includes a main panel 48 and a lower panel, shown as a closure panel 50, that is movable relative to the main panel 48 in a vertical direction between an extended position and a retracted position. The door 46 is made primarily of metal or a metal alloy, such as steel or aluminum. For example, the main panel 48 is formed of inner and outer metal skins 48a, 48b (see also [Fig.7]) which form a pocket therebetween which is configured to receive the closure panel 50 therein when the closure panel 50 is in the retracted position. The closure panel 50 may be made of metal, metal alloy, polymeric materials, fiber-reinforced polymer composites, and / or combinations thereof.
[0036] The closure panel 50 is an important feature of the ground support tractor 10 because it provides shielding and / or sealing functionality in the area forward of the wheel well 18, beneath the main panel 48 of the door 46, and above the cab floor 32 that might otherwise be open to the environment. More specifically, during operation of the ground support tractor 10, the closure panel 50 protects the interior of the cab 38 and the operators of the ground support tractor 10 from unpleasant external environments such as wind, rain, snow, and ice. In addition, the closure panel 50 helps maintain a desired temperature in the cab 38 by retaining warm air in the winter and retaining cooled air in the summer.Having a closing panel extending under an upper portion of the front wheel arch, however, creates some difficulties when opening the associated door, as the closing panel tends to collide with the wheel arch when the door is opened. Attempts have been made to solve this problem in . using pivoting doors or doors having a lower panel that pivots relative to an upper panel. In the former case, these designs require complex mechanisms and dedicated actuation means to pivot the full weight of the door around the wheel well. In the latter case, it has been found that pivoting of the lower panel relative to the upper panel can lead to jamming and / or malfunction of the lower panel over time. In the present disclosure, these and other disadvantages of current ground support tractor door designs are overcome by configuring the ramp 44 to apply a retracting force to the closing panel 50 that causes the closing panel 50 to move from the extended position to the retracted position in response to the movement of the door 46 from the closed position to the open position.
[0037] Referring also to Figures 3A-3D and 4A and 4B of the drawings, the cab 38 includes a windshield 52 and a rear window 54 that allow operators of the ground support tractor 10 to see in front of and behind the ground support tractor 10 during operations. The cab 38 also includes a roof 56 having a plurality of safety lights 58 that provide protection for the operators of the ground support tractor 10 and components within the cab 38. Within the cab 38 are the driver's seat 60a and the passenger seat 60b from which the operators control the ground support tractor 10. The ground support tractor 10 includes a driver's side door assembly 40a and a passenger's side door assembly 40b, each configured to selectively activate and prevent entry into and exit from the cab 38.
[0038] The operation of the driver-side door assembly 40a will now be described. The door assembly 40a is configured to allow the door 46 to move relative to the cab 38 in a longitudinal direction of the ground support tractor 10, as indicated by the arrow 62 in [Fig. 4A], between a plurality of positions including a fully closed position (see Figs. 3A, 4A) and a fully open position (see Figs. 3D, 4D). In the fully closed position, the door 46 is in a fully forward orientation with the front latch of the latch assembly 64 coupled to a door striker, represented by a metal hook 66, which is coupled to a front portion of the door frame 68 and which secures the door 46 in the fully closed position (see also [Fig. 5A] showing an interior view of the driver's side door assembly 40a with the instrument panel and steering controls removed and [Fig.5B] showing the latch assembly 64 in the forward secured position). In this position, the door 46 has a sealing engagement with the door frame 68 provided by the front door seals 70a, 70b and the rear door seal 72. Additionally, in the fully closed position, the closure panel 50 is in the extended position. In the illustrated embodiment, in . Due to the force of gravity, the closure panel 50 has a contacting relationship with the cabin floor 32 that provides a substantial seal therewith. In other embodiments, a mechanical assist mechanism may be used to bias the closure panel 50 toward the extended position. For example, such mechanical assist mechanisms may include spring systems or piston assemblies. The sealing relationship of the door 46 with the door frame 68 and the cabin floor 32 not only prevents unpleasant external environments such as wind, rain, snow, and ice from entering the cabin 38, but also prevents heated or cooled air from escaping from the interior of the cabin 38.
[0039] When it is desired to open the door 46, the operator disengages the front latch of the latch assembly 64 from the metal hook 66 using the inside handle 74 or the outside handle 76 of the door assembly 40a. The door 46 is now free to move in the longitudinal direction relative to the car 38. The primary support for the door 46 is provided by an upper rail 78, shown as a telescopic slide assembly, which is coupled between an upper portion of the door frame 68 and an upper portion of the door 46, as best seen in [Fig. 8A]. In the illustrated embodiment, a lower portion of the door 46 has a guide shown as a C-channel 80 which is received on the lower rail 42, as best seen in [Fig. 6]. The lower rail 42 is positioned in a slot between the body panel 36b and the body panel 36e.Together, the upper rail 78 and the lower rail 42 constrain the door 46 to move in the longitudinal direction 62 with little or no movement in the lateral direction of the ground support tractor 10 or in the vertical direction, as indicated by the arrow 82 in [Fig. 4A]. In addition, the use of the upper rail 78 in conjunction with the lower rail 42 limits and / or prevents vibration of the door 46 relative to the door frame 68 during operations. Preferably, the C-channel 80, the lower rail 42 and / or the bearing surfaces therebetween are formed of a low friction, high wear resistance and low moisture absorption material such as an ultra high molecular weight polyethylene.In other embodiments, the bottom rail could alternatively include a telescopic slide assembly or other guide system configured to constrain the door 46 to move in the longitudinal direction 62 with minimal friction.
[0040] As best seen in Figures 3B and 4B, when the operator moves the door 46 from the fully closed position to the fully open position, the upper rail 78 extends, the C-channel 80 slides rearwardly along the lower rail 42, and the closure panel 50 begins to retract from the extended position into the main panel 48 of the door 46. More specifically, the closure panel 50 has a lifting surface 50a on its rear edge that is configured to interface with the ramp 44 of the bottom rail 42. In the illustrated embodiment, the ramp 44 has a slope of between thirty degrees and forty-five degrees and preferably about thirty-five degrees. Similarly, the lifting surface 50a has a slope of between thirty degrees and forty-five degrees and preferably about thirty-five degrees such that the lifting surface 50a and the ramp 44 have substantially corresponding or common slopes. In this manner, when the lifting surface 50a contacts the ramp 44 due to the rearward movement of the door 46, the ramp 44 applies a retracting force to the closure panel 50 that causes the closure panel 50 to begin retracting into the main panel 48.
[0041] As best seen in Figures 3C and 4C, as the operator further moves the door 46 from the fully closed position to the fully open position, the upper rail 78 continues to extend, the C-channel 80 advances rearwardly along the lower rail 42, and the lifting surface 50a moves fully up the ramp 44 until the closure panel 50 is moved from the extended position to the retracted position within the main panel 48 of the door 46. As illustrated, movement of the door 46 in the longitudinal direction rearwardly causes the closure panel 50 to move in the vertical direction upwardly relative to the main panel 48 of the door 46. This movement of the closure panel 50 causes the closure panel 50 to be fully retracted within the main panel 48 of the door 46.More specifically, the main panel 48 of the door 46 includes an inner skin 48a and an outer skin 48b that form a pocket therebetween that is sized to receive the closure panel 50 therein. A telescopic slide assembly 84, shown as a vertically oriented linear telescopic slide assembly, is coupled between the closure panel 50 and an inner surface of the inner skin 48a (see also [Fig. 7]). In the illustrated embodiment, the telescopic slide assembly 84 includes first and second slide members 84a, 84b, each of which is coupled between the closure panel 50 and the inner surface of the inner skin 48a. In other embodiments, a telescopic slide assembly could have other numbers of slide members greater than or less than two. Furthermore, in other embodiments, a telescopic slide assembly could be oriented non-vertically.Although the telescopic sliding assembly 84 has been described and shown as coupling the closure panel 50 to the inner skin 48a of the main panel 48, it should be understood by those skilled in the art that a telescopic sliding assembly could alternatively couple the closure panel 50 to the outer skin. 48b of the main panel 48. Furthermore, although the movement between the closure panel 50 and the main panel 48 has been described as being accomplished using a telescopic sliding assembly, those skilled in the art should understand that other systems could be used to establish the moving relationship between the closure panel 50 and the main panel 48, including, but not limited to, systems utilizing rails, slots, pins, pistons, or other sliding means.
[0042] As best shown in Figures 3D and 4D, the operator has moved the door 46 into the fully open position. In the fully open position, the door 46 is in a fully rearward orientation with the rear latch of the latch assembly 64 coupled to a door striker 86 supported by the rear door stop 88 which secures the door 46 in the fully open position (see also Figures 8A and 8B). In this position, the closure panel 50 remains in the retracted position within the main panel 48. In the fully open position, the door 46 allows entry and exit from the cabin 38.Thus, the closing panel 50 moves from the extended position to the retracted position using a non-pivoting linear motion and the door 46 moves from the fully closed position to the fully open position using a non-pivoting linear motion without being obstructed or blocked by the wheel arch 18 and without requiring complex mechanisms and dedicated actuation means.
[0043] When it is desired to close the door 46, the operator disengages the rear latch of the latch assembly 64 from the door striker 86 from the rear door stop 88 using the inside handle 74 or the outside handle 76 of the door assembly 40a. The door 46 is now free to move in the longitudinal direction relative to the car 38. More particularly, the door 46 can be moved in the longitudinal direction forward relative to the car 38, thereby collapsing the top rail 78 and causing the C-channel 80 to slide forward along the bottom rail 42. The closure panel 50 remains in the retracted position within the main panel 48 until the door 46 passes the location shown in Figures 3C and 4C.Next, the lifting surface 50a encounters the ramp 44 of the bottom rail 42 which allows a gravitational force to cause the closure panel 50 to move vertically downward relative to the main panel 48 as the lifting surface 50a moves down the ramp 44, as best seen in Figures 3B and 4B. When the operator has moved the door 46 to the fully closed position, as best seen in Figures 3A and 4A, the gravitational force causes the closure panel 50 to return to the extended position and reestablish contacting relationship with the car floor 32. In this position, the door 46 is in a fully forward orientation with the forward latch of the latch assembly. 64 coupled to the door striker 66 which secures the door 46 in the fully closed position. In this position, the door 46 has a sealing engagement with the door frame 68 provided by the front door seals 70a, 70b and the rear door seal 72. Thus, the closure panel 50 moves from the retracted position to the extended position using a non-pivoting linear motion and the door 46 moves from the fully open position to the fully closed position using a non-pivoting linear motion.
[0044] The foregoing description of embodiments of the disclosure has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the disclosure. The embodiments have been selected and described in order to explain the principles of the disclosure and its practical application to enable those skilled in the art to use the disclosure in various embodiments and with various modifications suitable for the particular use contemplated. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the embodiments without departing from the scope of the present disclosure.Such modifications and combinations of the illustrative embodiments as well as other embodiments will be apparent to those skilled in the art upon reference to the description. It is therefore intended that the appended claims encompass such modifications or embodiments.
Claims
Claims
1. A door assembly for a vehicle, the door assembly comprising: a bottom rail having a ramp; and a door slidably received by the bottom rail and movable relative thereto in a first direction between a closed position and an open position, the door having a main panel and a bottom panel that is movable relative to the main panel in a second direction between an extended position and a retracted position; wherein, the ramp is configured to apply a retracting force to the bottom panel that causes the bottom panel to move from the extended position to the retracted position in response to movement of the door from the closed position to the open position.
2. A door assembly according to claim 1, wherein the first direction is substantially perpendicular to the second direction.
3. A door assembly according to claim 1 or claim 2, wherein the first direction is a longitudinal direction and the second direction is a vertical direction.
4. A door assembly according to claim 1 or claim 2 or claim 3, wherein the main panel further comprises inner and outer skins; and wherein, in the retracted position, the lower panel is disposed between the inner and outer skins.
5. A door assembly according to claim 4, wherein the lower panel is slidably coupled to an interior surface of one of the inner and outer skins of the main panel.
6. A door assembly according to claim 1 or any one of claims 2 to 5, wherein the ramp has a slope of between thirty degrees and forty-five degrees.
7. A door assembly according to claim 1 or any one of claims 2 to 5, wherein the ramp has a slope of about thirty-five degrees.
8. A door assembly according to claim 1 or any one of claims 2 to 7, wherein the lower panel further comprises a lifting surface configured to contact the ramp; and wherein the ramp and the lifting surface have substantially common slopes.
9. A ground support tractor comprising: a wheeled chassis; a cab mounted on the wheeled chassis; and a door assembly coupled to the cab, the door assembly comprising: a bottom rail having a ramp and a door slidably received by the bottom rail and movable in a first direction relative to the cab between a closed position and an open position, the door comprising a main panel and a closure panel that is movable relative to the main panel in a second direction between an extended position and a retracted position, the second direction being substantially perpendicular to the first direction; wherein, the ramp is configured to apply a retracting force to the closure panel that causes the closure panel to move from the extended position to the retracted position in response to movement of the door from the closed position to the open position.
10. The ground support tractor of claim 9, wherein the door assembly further comprises an upper rail; and wherein the lower rail and the upper rail limit movement of the door to movement in the first direction relative to the cab.
11. A ground support tractor according to claim 9 or claim 10, wherein the door assembly further comprises a front latch configured to secure the door in the closed position.
12. A ground support tractor according to claim 9 or claim 10 or claim 11, wherein the door assembly further comprises a rear latch configured to secure the door in the open position.
13. A ground support tractor according to claim 9 or any one of claims 10 to 12, wherein the cab further comprises a cab floor; and wherein the closure panel has a contacting relationship with the cab floor when the door is in the closed position.
14. A ground support tractor according to claim 9 or any one of claims 10 to 13, wherein the closure panel is disposed inside the main panel when the closure panel is in the retracted position.
15. A ground support tractor according to claim 9 or any one of claims 10 to 14, wherein the main panel further comprises inner and outer skins; and wherein, in the retracted position, the closure panel is disposed between the inner and outer skins.
16. The ground support tractor of claim 15, wherein the door assembly further comprises a telescopic sliding assembly coupled between the closure panel and at least one of the inner and outer skins.
17. The ground assist tractor of claim 16, wherein the telescopic slide assembly further comprises a vertically oriented linear telescopic slide assembly.
18. A ground assist tractor according to claim 9 or any one of claims 10 to 17, wherein the closure panel moves from the retracted position to the extended position in response to a gravitational force as the door moves from the open position to the closed position.
19. A ground support tractor comprising: a wheeled chassis; a cab mounted on the wheeled chassis; and a door assembly coupled to the cab, the door assembly comprising: a bottom rail having a ramp; and a door slidably received by the bottom rail and movable in a longitudinal direction relative to the cab between a closed position and an open position, the door comprising a main panel and a closure panel movable in a vertical direction relative to the main panel between an extended position and a retracted position, the closure panel having a lifting surface; wherein, the closure panel is in the extended position when the door is in the closed position; wherein, the closure panel is in the retracted position when the door is in the open position;wherein the closing panel moves from the extended position to the retracted position in response to contact between the lifting surface and the ramp as the door moves from the closed position to the open position; and; wherein the closing panel moves from the retracted position to the extended position as the door moves from the open position to the closed position.
20. The ground assist tractor of claim 19, wherein the ramp is configured to apply a retracting force to the closure panel that causes the closure panel to move from the extended position to the retracted position in response to movement of the door from the closed position to the open position; and wherein the closure panel moves from the retracted position to the extended position in response to a gravitational force as the door moves from the open position to the closed position.