Seat dewrinkling method and apparatus

A system and method for removing wrinkles from the covering material of seats for automobiles and other vehicles. The invention may be implemented in a seat dewrinkling oven that includes front and rear heaters that conform to the shape of the seat being heated. In particular, a front heater may be employed that includes a vertically oriented portion for directing heat at the vertically oriented back portion of a front seat surface and a horizontally oriented portion for directing heat at the horizontally oriented bottom portion of the seat front surface. Preferably medium wavelength infrared heating elements are employed in the heaters to provide better heat penetration and dewrinkling.

FIELD OF THE INVENTION

The present invention pertains generally to industrial heating devices and methods, such as industrial ovens and methods for their use, and, more particularly, to ovens and other heating devices and methods for removing wrinkles from seat material applied to seats for automobiles and other vehicles.

BACKGROUND OF THE INVENTION

Typical seats for automobiles and other vehicles are formed on a metal frame to which padding is attached. The padding may typically be formed of a synthetic foam material that is covered with a natural or man made covering material. For example, the seat covering material may typically be leather, vinyl, or some type of cloth. The covering material may be applied to the seat by attaching the covering material over the foam padding either prior to or after attaching the padding to the seat frame or by stuffing the padding into the covering material before attaching the padding to the seat frame.

A very common problem associated with seats constructed in the manner just described is that, immediately after assembling the seat, the seat covering material is often wrinkled. This wrinkled appearance is very unacceptable to purchasers of the vehicles in which the seats are installed. Purchasers desire to see smooth wrinkle free seat surfaces.

It has been found that the wrinkles appearing in seat covering material may be removed by heating the seat covering material at a relatively high temperature for a short duration. If the right temperature and time of exposure is applied, heat can be used to remove wrinkles from the seat covering material without scorching or otherwise damaging the seat material. A typical device employed by manufacturers to apply such heat to a seat for removing wrinkles from the covering material thereof is a seat dewrinkling oven or, in short, a seat oven.

A conventional seat oven10is illustrated in, and will be described with reference to,FIG. 1. The conventional seat oven10typically is formed in an enclosure12, which may, for example, include insulated walls14to keep the heat generated by the oven contained therein. At least one side16, and preferably two opposed sides, of the oven10are open, or openable, to allow a seat18to be placed therein for dewrinkling. The oven10typically includes some kind of support structure20for supporting the seat18within the oven10. The support structure20may, for example, be part of a conveyor system for both supporting the seat18within and transporting the seat18through the oven10.

A typical seat18for an automobile or other vehicle has a generally vertically oriented rear surface22and a front surface24. The front surface24of the seat18forms the part of the seat that is sat upon. The front surface24of the seat18thus comprises a generally vertically oriented back portion26and a generally horizontally oriented bottom portion28. The junction point30between the back portion26and the bottom portion28of the front surface24of the seat18is commonly known as the seat bight.

A conventional seat oven10typically employs two heaters: a generally vertically oriented rear heater32, for applying heat to the vertically oriented rear surface22of the seat18, and a front heater34. Both the rear32and the front34heaters typically may be formed of a plurality of generally horizontally and parallel arranged infrared heating elements36(e.g., rods or lamps) that generate short wave infrared radiation (e.g., generally in the wavelength range of 0.75–2 microns). The heating elements36may be mounted within parabolic or other reflectors38to enhance the heat radiation that is directed from the heaters32and34toward the seat18.

As illustrated inFIG. 1, the front heater34as employed in a conventional seat dewrinkling oven10presents a substantially planar heating surface that is typically positioned in front of and above the front surface24of the seat18to direct the infrared energy generated thereby down onto the front surface24of the seat18. With this conventional type of heater34, distances of the various parts of the front surface24of the seat18from the heating surface vary significantly. With this configuration, for example, the front heater34is positioned very close to a top of the back portion26of the front surface24and a front of the bottom portion28of the front surface24of the seat18. The seat bight30, in contrast, is positioned much further away from the front heater34. Thus, using this conventional configuration, the heat applied to the front surface24of the seat is not even across the surface thereof. Sufficient heat intensity, and the duration of application thereof, must be applied by the front heater34to remove wrinkles from the seat18at and around the seat bight30, which is far removed from the heater34. However, in a conventional seat oven, such applied heat, and the duration of application thereof, needed to remove wrinkles from the seat18near the bight30may be more than is required to remove wrinkles from the portions of the front surface24of the seat18that are more closely positioned relative to the heater34.

What is desired, therefore, is a method and apparatus for applying heat to the covering material of a seat for an automobile or other vehicle in a manner such that the heat is applied evenly over the surface of the seat thereby to remove wrinkles from the seat covering material in a time and energy efficient manner.

SUMMARY OF THE INVENTION

The present invention provides an improved system and method for dewrinkling the covering material used on seats for automobiles and other vehicles. The present invention may be implemented in a seat dewrinkling oven employing heaters that are positioned within the oven so as to be contoured to the shape of the seat surfaces to be heated. Thus, in accordance with the present invention, heat is applied evenly to the seat covering material, thereby to remove wrinkles therefrom in a reduced amount of time and employing a reduced amount of energy, while thereby also reducing the risk of damage to the seat during the heating process. Preferably the heaters employed in accordance with the present invention may be adjustable in position to allow a seat dewrinkling oven in accordance with the present invention to be used to remove wrinkles from seats having a variety of seat shapes. A seat oven in accordance with the present invention preferably employs infrared heating elements which provide medium-wavelength infrared energy, e.g., generally in the range of 2–4 microns, which has been found to be more effective for removing wrinkles from a variety of different seat covering materials.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described in detail with reference to the illustration inFIG. 2of an exemplary seat dewrinkling oven40in accordance with the present invention. The seat dewrinkling oven40in accordance with the present invention preferably includes a housing or other support structure42within which the other components of the oven are enclosed or to which the other components of the oven are attached. The housing structure42preferably may be of high strength tubular construction, e.g., using high strength tubular steel components, such that the enclosure structure42is easily assembled in position at a desired location while providing sufficient strength and durability to support the other components of the oven40as well as one or more seats18that are placed in the oven40for dewrinkling.

At least two walls44and46of the support structure42may be enclosed and insulated to retain heat generated by the oven40within the oven. A box48or other structure containing the controls for the oven40preferably may be mounted to one of the closed insulated walls44of the oven40. The insulated wall44in this case also provides protection of the controls48from the heat generated within the oven40.

At least one side50of the oven may be open, or openable, to allow one or more seats18to be placed therein for dewrinkling. Preferably opposed sides of the oven40may be open or openable to allow seats18to be passed through the oven40from one side thereof to the other for dewrinkling therein.

A seat support structure52preferably is provided within the oven40to support and maintain a seat18in the desired position within the oven40during the dewrinkling process. This seat support structure52may include or be part of a conventional conveyor system whereby seats18may be supported within and conveyed through the oven40for dewrinkling in the manner to be described below.

A seat dewrinkling oven in accordance with the present invention preferably includes a rear heater54and a front heater56. The rear heater54is positioned within the oven40to direct heat at the rear surface22of a seat18to remove wrinkles from the covering material thereof. The front heater56is positioned within the seat dewrinkling oven40to direct heat at the front surface24of the seat18to remove wrinkles from the covering material thereof. In accordance with the present invention, the rear54and front56heaters are positioned and shaped so as to direct heat evenly across the surfaces of the seat18from which wrinkles are to be removed, thereby to remove the wrinkles in a time and energy efficient manner.

The rear heater54is generally vertically oriented within the seat dewrinkling oven40, thereby to direct heat at the generally vertically oriented rear surface22of a seat18. The rear heater54may be mounted in a position within the seat dewrinkling oven40by attaching the rear heater54to the oven support structure42. For example, the rear heater54may be mounted to the housing support structure42via one or more generally horizontally oriented supports arms58that are bolted or otherwise attached to the support structure42to extend therefrom into the oven40.

The rear heater54preferably may be mounted within the seat dewrinkling oven40such that the distance and/or orientation thereof with respect to the seat18to be heated is adjustable. For example, the one or more support arms58to which the rear heater54is mounted may include a horizontally oriented slot or track60. The rear heater54is attached to the support arm58via a threaded rod or bar attached to the heater54and extending through or into the one or more slots or tracks60such that the rear heater54can be moved in position horizontally along the slot or track60and rotated in position with respect to an axis of rotation extending through the slot or track60. A hand operated knob62or other similar structure may be employed to fix the rear heater54in position with respect to the mounting arm58when the desired position and orientation for the rear heater54is established.

The rear heater54preferably includes a plurality of heating elements64. (SeeFIG. 3) The heating elements employed preferably are elongated rod shaped heating elements64, a plurality of which are mounted parallel with each other in a generally horizontal orientation to form the rear heater54. Preferably, infrared heating elements64that provide primarily medium-wave infrared energy, e.g., in a wave length range of approximately 2–4 microns, are employed. Exemplary heating elements64of this type include the Fannon Goldenrod medium-wavelength infrared lamps. These heating elements include gold internal reflectors, thereby eliminating the need to use external reflectors as part of the rear heater54. The individual heating elements64preferably may be attached to the rear heater54via high quality insulated ceramic terminals66, that provide for easy removal and replacement of the heating elements64employed.

The front heater56employed in a seat dewrinkling oven40in accordance with the present invention preferably includes a generally vertically oriented portion68thereof and a generally horizontally oriented portion70thereof. The generally horizontally oriented portion70of the front heater56is positioned with respect to the generally vertically oriented portion68thereof such that the vertically68and horizontally70oriented portions of the front heater56form the complimentary shape to the front surface24of a seat18. Thus, the shape of the front heater56is contoured to the shape of the front surface24of the seat, thereby heating the front surface24of the seat18evenly to remove wrinkles therefrom.

The front heater56may be mounted within the oven40via a mounting structure attached to the oven support structure42that allows a variety of adjustments of the position and orientation of the front heater56within the oven40and thus with respect to the seat18. For example, a mounting structure72attached to the oven support structure42may include a horizontal track to which a telescoping vertical support arm74is moveably attached. The front heater56preferably may be rotatably attached to the telescoping vertical support arm74at an end thereof opposite the end of the telescoping vertical support arm74that is moveably attached to the horizontal track mounting structure72. Thus, the telescoping vertical support arm74may be moved along the horizontal track mounting structure72to adjust the horizontal position of the front heater56within the oven and with respect to a seat18. The telescoping vertical support arm74may be extended or retracted to adjust the vertical position of the front heater56within the oven and with respect to a seat18. The front heater56may be rotated with respect to the telescoping vertical support arm74to which it is attached to adjust the orientation of the front heater56with respect to the seat18. A hand operated knob76or other similar structure may be employed to fix the front heater56in rotational position when the desired orientation for the front heater56is established.

The angle of the vertical portion68of the front heater56with respect to the horizontal portion70thereof, and vice versa, preferably may be adjustable as well. This allows for the shape and orientation of the front heater56to be adjusted to accommodate the shape of the front surfaces24a variety of seats18. For example, the horizontal portion70of the front heater56may be joined to the vertical portion68thereof at a moveable hinge78or similar structure. Thus, the horizontal portion70may be moved with respect to the vertical portion68of the front heater56about the hinge78to adjust the angle between the two portions68and70to correspond to the angle between the back portion26and bottom portion28of the front surface24of a seat to be heated using the front heater56. A hand operated knob79and/or other appropriate structure may be employed to fix the angular position of the horizontal portion70of the front heater56with respect to the vertical portion68thereof when the desired angle between the two portions68and70is established.

Both the vertical68and horizontal70portions of the front heater56may include a plurality of generally horizontally oriented elongated heating elements64mounted parallel to each other. (SeeFIG. 4) Preferably medium-wavelength tubular infrared heaters are employed in the front heater56, as described above with respect to the rear heater54. As with the rear heater54, the heating elements64preferably may be attached to the front heater56via high quality insulated ceramic terminals66, that provide for easy removal and replacement of the heating elements64employed.

To provide adequate heating to remove wrinkles from the front surface24of the seat18in and around the seat bight30, the front heater56may include one or more heating elements80that are positioned at the transition or corner formed between the vertical68and horizontal70portions of the front heater56. Such bight heating elements80ensure even heating across the front surface24of the seat, including of the seat bight30. Note that the bight heating elements80may project forward from the planes of heating elements of the vertical portion68and/or horizontal portion70of the front heater56, thereby to project heat better into the seat bight30.

The front56and rear54heaters preferably may be controlled by a control system. An exemplary control system90that may be employed in a seat dewrinkling method and apparatus in accordance with the present invention is illustrated inFIG. 5, and will be described with reference thereto. It should be understood that control systems other than the exemplary control system90to be described, including conventional control systems, may be employed in a seat dewrinkling method and apparatus in accordance with the present invention.

The exemplary control system90may include a controller92that may be implemented using conventional electronic circuitry, such as one or more microprocessors, microcontrollers, or other programmable devices and/or using discrete digital and/or analog circuitry. The controller92generates control signals that are provided, via appropriate heater controllers/drivers94, to control operation of the heating elements64of the front56and rear54heaters. Independent control preferably is provided for each of the front56and rear54heaters. Individual heating elements64or groups of heating elements64within the heaters56and54may also be independently controlled by the controller92. For example, the heating elements64in the vertical portion68and horizontal portion70of the front heater56may be controlled independently from each other as well as from the bight heating elements80. Such independently controlled heating zones allow the right amount of heat to be provided to various portions of the seat18to remove wrinkles from the seat covering material effectively and rapidly without applying too much heat to any part of the seat18.

The controller92provides control signals to control the heaters54and56to turn the heating elements64on and off at the desired times as well as to control the heater output, when the heating elements64are turned on, to a desired percentage of the maximum output of the heating elements64. The desired heat output may be set manually by an operator, e.g., using an operator input device96, such as a conventional dial and/or keypad input device coupled to the system controller92. Alternatively, or additionally, the control system90may employ one or more heat sensors98to provide temperature feedback to the system controller92that the system controller92employs to control operation of the heating elements64in the heaters54and56to maintain a desired temperature range. For example, one or more pyrometers, such as optical pyrometers, may be mounted at appropriate positions in the oven40, e.g., on the housing structure42, to sense the temperatures at selected locations on the surface of a seat18being dewrinkled in the oven to provide the desired feedback to the system controller92.

The control system90may be coupled to the control system of a conveyor system100for conveying seats18to be dewrinkled through the oven40, thereby to coordinate control of the heaters56and54with operation of the conveyor system100. A conveyor system100may convey seats18continuously through the oven40for dewrinkling. Alternatively, the conveyor system100may convey seats18into the oven40, pause while the seat18is heated by the heaters54and56to remove wrinkles from the covering material thereof, and then convey the dewrinkled seat18out of the oven. (This “indexing” of seats18through the oven40may be required where pyrometers or other heat sensors98are used to sense the seat surface temperature to provide feedback to the system controller92.) In the latter case, for example, the conveyor system100may provide a signal to the controller92to indicate that a seat18has been moved into the oven and is ready to be heated to remove wrinkles therefrom. Similarly, the controller92may provide a signal to the conveyor system100to indicate that the dewrinkling is complete and the seat18may be conveyed out of the oven40.

The controller92may also provide indications, via one or more operator output devices102, such as indicator lights, a display screen, etc., to an operator to indicate, e.g., proper system operation, system errors, heating times, temperatures detected by the heat sensors98, etc.

As mentioned above, all heat sensitive components of the control system90may be mounted in an insulated box48or other enclosure that, in turn, is mounted on the oven support structure42outside of the oven.

Experimentation has confirmed that the heating of seat covering material to remove wrinkles therefrom using medium wave infrared heaters and the heater configuration as illustrated inFIG. 2is more effective than the use of short wave infrared heaters and a conventional heater configuration (FIG. 1). Tests were conducted using the two different configurations to heat a variety of different seat covering materials. The temperatures of the heated side and the back (unheated) side of the seat material were measured to determine the penetration of the heat through the material. It is generally recognized that good heat penetration of the seat covering material is required to provide for rapid and effective dewrinkling of the material.

A charcoal gray vinyl material was exposed for fifteen seconds using the medium wave infrared heaters with internal reflectors described herein and with the short wave heaters with external reflectors as commonly used in the prior art. (The heat density applied was the same.) With the medium wave heaters, the heated side of the covering material reached a temperature of 210° F., with the backside of the material reaching a temperature of 206° F., for a difference of only 4° F. In contrast, using the short wave heaters, with clean reflectors, the heated side of the seat material reached a temperature of 220° F. with the back side thereof reaching a temperature of 195° F., for a 25° difference. For short wave heaters with tarnished reflectors the heated side reached a temperature of only 145° F., with the backside of the material reaching a temperature of 122° F., for a difference of 23° F.

The same experiment was repeated with a light gray leather seat covering material that was exposed to heat for twenty five seconds. Using the medium wave internal reflector heaters described herein, the heated side of the material reached a temperature of 270° F. with the backside of the material reaching a temperature of 267° F., for a difference of 3° F. Using the short wave heaters with clean reflectors, the heated side of the covering material reached a temperature of 248° F., with the back side of the material reaching a temperature of 210° F., for a difference of 38° F. Using short wave heaters with tarnished reflectors the heated side of the covering material only reached a temperature of 173° F., with the back side of the material reaching a temperature of 147° F., for a difference of 26° F.

The experiment was repeated again with a black leather seat covering material, which was exposed to heat for twenty-seven seconds. Using the medium wavelength heaters with internal reflectors described herein the heated side of the material reached a temperature of 270° F., with the back side of the material reaching a temperature of 218° F., for a difference of 52° F. Using conventional short wave heaters with clean external reflectors the heated side of the material reached a temperature of 310° F., with the back side of the material reaching a temperature of 220° F., for a difference of 90° F. Using the short wave heaters with tarnished reflectors the heated side of the material reached a temperature of 195° F. with the back side of the material reaching a temperature of 143° F., for a difference of 52° F.

These experiments indicate that the back side of a seat covering material is heated consistently to a higher temperature using the medium wave internal reflector heaters described herein. This is true even though the average heat density (Watt/in2) generated by the heaters is identical. The difference between the temperatures achieved on the heated and back sides of the covering material with the medium wavelength internal reflector heaters indicates that these heaters exhibit better penetration and, therefore, better dewrinkling characteristics than conventional short wave heaters.

It should be understood that the present invention is not limited to the particular exemplary applications and embodiments illustrated and described herein, but embraces all modified forms thereof as come within the scope of the following claims.