Safety back-up sensor for a vehicle

[0002] 1. Field of the Invention

[0003] The present invention relates to a safety back-up sensor, in particular, a sensor with multiple resilient tabs on the shoulder to prevent shifting or rotation of the sensor body, allowing the sensor to be firmly affixed on a vehicle bumper.

[0004] 2. Description of Related Art

[0005] When an ordinary user wants to install a sensor deice in the vehicle, his or her main consideration is the accuracy in detecting the proximity of an object. Elements causing false alarms of the electronic sensor can be either external factors or circuit design problems. The user wants to know whether the sensor device is capable of distinguishing actual objects from noises and accurately approximating the distance between the vehicle and the object, based on the reflection of ultrasonic signals emitted. A primary consideration is whether the sensor is rigidly installed in place so the device can function properly.

[0006] With reference to FIG. 5, a conventional back-up sensor device includes a cylindrical body (40), an end plate (43), a rubber bushing (41) and a signal sensor module (42). A hollow core runs through the cylindrical body (40) to accommodate the rubber bushing (41) and the signal sensor module (42). The signal sensor module (42) emits ultrasonic signals through a through hole in the cylindrical body (40) to detect any object within its effective range.

[0007] In the conventional method of installing a sensor device, a hole is drilled in the rear bumper of the vehicle, in which the sensor device is installed. When the sensor device is inserted into the bumper, the security of the installation relies on the abrasion force of the external wall of the sensor against the inner wall of the installation hole to grip the device. The external wall of a conventional sensor body (40) usually has a smooth surface. A vehicle riding over bumpy roads is likely to cause rocking, bouncing and vibration of the vehicle chassis and the bumper. Over an extended period of time, the sensor body (40) will likely loosen or become detached from the installation hole.

[0008] When assembling the conventional sensor device, the signal sensor module (42) is first inserted into the rubber bushing (41), and the rubber bushing (41) is slid into the body of sensor (40). As such, the sensor body indirectly exerts pressure on the perimeter of the signal sensor module, which may cause dislocation of the sensor leading to aberrations in signal transmission and reception. This phenomenon may well cause false alarms due to incorrect approximation of the distance between an object and the sensor device.

[0009] To overcome the shortcoming in the conventional sensor device mentioned above, the present invention provides a type of vehicle back-up sensor, wherein multiple directional and locating constructs are created on the shoulder of the external sensor body to ensure rigid installation of the back-up sensor on the vehicle bumper under all driving conditions.

[0010] The safety back-up sensor presented in this invention comprises a cylindrical body with a hollow tubular core to accommodate a rubber bushing, in which a signal sensor module is installed on one end. The shoulder of the external sensor body has multiple convex-shaped resilient tabs having the appearance of a fretted carving. The top portion of each resilient tab is impressed with transverse teeth to prevent the sensor unit from shifting. Alternately, double ribs over transverse teeth are created on every other resilient tab to prevent the sensor unit from rotating. With these special features, the sensor unit can be firmly attached to the vehicle bumper.

[0011] Other objectives, advantages, and novel features of the invention will become apparent from the detailed description when taken in conjunction with the attached drawings.

[0012] FIG. 1 is an exploded perspective view of the safety back-up sensor in accordance with the present invention;

[0013] FIG. 2 is a side view of the safety back-up sensor in FIG. 1;

[0014] FIG. 3 is a cross sectional side plan view of the safety back-up sensor in FIG. 2;

[0015] FIG. 4 is a cross sectional bottom plan view of the safety back-up sensor in FIG. 1;

[0016] FIG. 5 is an exploded perspective view of a conventional sensor back-up device for a vehicle in accordance with the prior art.

[0017] With reference to FIGS. 1 and 2, the safety back-up sensor in accordance with the present invention comprises a cylindrical jacket (10), a rubber bushing (20), a signal-sensing transceiver (30) and an end plate (35).

[0018] The cylindrical jacket (10) has a hollow center, two open ends and an inside and outside surface. The hollow center extends to the outside through an integrated bezel (11) at one end. Pairs of parallel longitudinal through slots (12) are formed through the cylindrical jacket (10). Each longitudinal through slot (12) has two ends, and the ends of each pair is connected by a transverse through slot (not numbered) at the end adjacent to the bezel (11) to form a resilient tab (13) between each pair of longitudinal through slots (12). An outside surface of each resilient tab (13) extends out from the outside surface of the cylindrical jacket (10) in a triangular configuration. In the current embodiment four resilient tabs (13) are disposed in parallel. The parallel resilient tabs (13) extend from near one end of the cylindrical jacket (10) toward the bezel (11) but do not touch the bezel (11), thus forming a free end.

[0019] Multiple transverse teeth (14) are formed on the outside portion of alternate resilient tabs (13) toward the free end. Parallel ribs (15) are formed on the other resilient tabs (13). A rectangular engagement hole (16) is formed near the attached end of each resilient tab (13).

[0020] An axial channel (17) is formed between adjacent pairs of resilient tabs (13) on the inner surface on the jacket (10) to hold the rubber bushing (20) in place.

[0021] The external wall of the rubber bushing (20) has multiple parallel grooves (21) and multiple ridges (22). The grooves (21) correspond to the positions of resilient tabs (13) on the jacket (10). The ridges (22) correspond to the axial channels (17) on the inner surface of the jacket (10).

[0022] With reference to FIGS. 1 and 3, to assemble the back-up sensor, firstly, the signal sensor module (30) is inserted into one end of the rubber bushing (20). Secondly, the rubber bushing (20) is slid into the jacket (10). Finally, the end plate (35) is fit into the end of the jacket (10) opposite from the bezel (11) to securely hold the bushing (20) in the jacket (20). The end plate (35) has an outer edge (not numbered) with multiple locking tabs (36) corresponding to the positions of engagement holes (16) on the jacket (10). These locking tabs (36) allow the end plates (35) to be rigidly attached to the jacket (10).

[0023] With reference to FIG. 4, each ridge (22) on the rubber bushing (20) is lodged in the corresponding channel (17) on the inner wall of the jacket (10), so that the rubber bushing (20) can be firmly affixed to prevent turning of one part in relation to the other. The external wall of the rubber bushing (20) has multiple parallel grooves (21) corresponding to the positions of resilient tabs (13) on the jacket (10), so that in between the rubber bushing (20) and the jacket (10) a gap is formed. With the foregoing structure, the pressure directly applied to the signal sensor module can be reduced, thereby reducing the false alarm rate when backing up to park a vehicle.

[0024] Again referring to FIGS. 1 and 2, when the back-up sensor presented in the invention is installed on the vehicle bumper, the protruding resilient tab (13) on the cylindrical body (10) produces a strong gripping force on the inner wall of the hole used for installation of the sensor body, so that the sensor body can be firmly affixed on the vehicle bumper. In addition, the transverse teeth (14) present on the resilient tab (13) are used to further increase the abrasion force against the inner wall of the installation hole to prevent shifting of the sensor body (10), and the ribs (15) are designed to counter the rotational force on the sensor body.

[0025] The present invention provides a safety back-up sensor that can be rigidly installed in a vehicle bumper by means of and the protruding resilient tabs with transverse teeth and ribs. It is apparent that the back-up sensor with the improved body structure is capable of enhancing the efficacy in giving warning of the proximity of an object compared to conventional sensor devices.

[0026] The foregoing illustration of the preferred embodiment of the present invention is intended to be illustrative only, and under no circumstances should the scope of the present invention be so restricted.