This invention relates generally to automotive vehicles having convertible roofs and specifically to a sensor system for detecting undesired objects in a convertible roof storage compartment.
Convertible roofs are commonly provided on many automotive vehicles. These convertible roofs are movable from a raised position attached to a front windshield header to a lowered or stowed position within a storage compartment. Traditionally, the storage compartment is located within a trunk space which is accessible by opening a trunk or deck lid about a rear pivot. The storage space is alternately between a rearmost passenger seat and a trunk, and is often called a boot.
Conventional convertible roofs include both hard-top and soft-top constructions. Examples of such conventional hard-top systems are disclosed within the following U.S. patents: U.S. Pat. No. 5,195,798 entitled "Retractable Roof for Vehicles" which issued to Klein et al. on Mar. 23, 1993; U.S. Pat. No. 4,854,634 entitled "Upper Body Structure for a Convertible Vehicle" which issued to Shiraishi et al. on Aug. 8, 1989; U.S. Pat. No. 2,939,742 entitled "Foldable Vehicle Top" which issued to Dardarian et al. on Jun. 7, 1960; U.S. Pat. No. 2,704,225 entitled "Convertible Automobile Top" which issued to Anschuetz et al. on Mar. 15, 1955; and, U.S. Pat. No. 2,007,873 entitled "Vehicle Body Top Capable of Being Stowed Away" which issued to Paulin on Jul. 9, 1935. Examples of conventional soft-top convertible roofs include U.S. Pat. No. 4,720,133 entitled "Convertible Top Structure" which issued to Alexander et al. on Jan. 19, 1988; and, U.S. Pat. No. 4,958,882 entitled "Folding Top for Vehicles" which issued to Kolb on Sep. 25, 1990. The disclosures of all the afore-mentioned conventional convertible roof patents are incorporated by reference herewithin.
Objects left in the trunk or boot storage compartments can cause a severe problem upon retraction of these convertible roofs. A jack, briefcase or even an object as small as a golf ball can break a glass backlite and bend linkages when inadvertently pressed thereagainst. The likelihood of such an event is further heightened with the ever increasing use of electric motors to automatically drive the convertible top-stack linkages.
Unrelated to convertible roofs, occupant sensors have been used in seat belt systems for a number of years. Examples of such a seat occupant sensor are disclosed within the following U.S. patents: U.S. Pat. No. 4,107,645 entitled "Seat Belt System with Starter Engine Lock and Alarm" which issued to Lewis et al. on Aug. 15, 1978; U.S. Pat. No. 3,859,485 entitled "Occupant Sensor Seat Switch" which issued to Blinkilde et al. on Jan. 7, 1975; U.S. Pat. No. 3,845,261 entitled "Occupant Sensor Seat Switch with Deformable Conductive Spacer Pads" which issued to Blinkilde on Oct. 29, 1974; U.S. Pat. No. 3,761,658 entitled "Load Responsive Switch" which issued to Loose et al. on Sep. 25, 1973; and, U.S. Pat. No. 3,715,541 entitled "Cushion Seat Switch Sensor Means" which issued to Koenig on Feb. 6, 1973; the disclosures of which are all incorporated by reference herewithin. While seat sensors have proven effective in detecting a person occupying a seat, these conventional sensors have not been employed in combination with a convertible roof for preventing inadvertent destruction thereof upon retraction.
In accordance with the present invention, a preferred embodiment of a sensor system is located in a storage compartment of an automotive vehicle for preventing full retraction of a convertible roof when an undesired object is detected within the storage compartment. In one aspect of the present invention, a sensor employs a pair of nominally separated conductive layers. This sensor construction transmits an electrical signal when the weight of an undesired object places the conductive layers in electrical contact or moved toward each other. A further aspect of the present invention provides a sensor system capable of transmitting and receiving waves. In another aspect of the present invention, an electric roof motor is controlled by an electrical control unit which operates the motor responsive to a signal transmitted by a sensor coupled thereto. In yet another aspect of the present invention, a method of using and a method of retrofitting an automotive vehicle with a convertible roof and an object sensor system is provided.
The sensor system of the present invention is advantageous over traditional systems. For example, a sensor of the present invention prevents inadvertent damage to a convertible roof upon retraction thereof. Furthermore, a sensor of the present invention can detect objects as small and light weight as a golf ball. The present invention sensor system is also advantageous in that it takes up a minimal amount of packaging space within a storage compartment. Moreover, the present invention sensor system controls an electromagnetic device through an electrical control unit. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.