Window, notably automobile vehicle windscreen, including an integrated ultrasonic device for detecting the presence of foreign bodies on one of its faces

• US 5,436,060 A
• Filed: 08/08/1994
• Issued: 07/25/1995
• Est. Priority Date: 09/03/1993
• Status: Expired due to Fees

• Current Assignee: Asulab SA (The Swatch Group AG)
• Original Assignee: Asulab SA (The Swatch Group AG)
• Inventors: Duthe, Bernard, Saurer, Eric, Jeanmonod, Roland
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): JEWIK, PATRICK
• Application Number:
  US08/286,958
• Time in Patent Office: 351 Days
• Field of Search: 428/209, 428/34.4, 428/195, 428/45, 428/46, 428/34, 428/38, 318/483, 340/550, 340/391.1, 310/322, 367/188
• US Class Current: 428/195.1
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B60S 1/0822 characterized by the arrangement or type of detection means
• CPC Class Codes: B60S 1/0855 Ultrasonic rain sensor
• CPC Class Codes: B60S 1/0877 at least part of the sensor being positioned between layers of the windshield
• CPC Class Codes: Y10T 428/131 Glass, ceramic, or sintered, fused, fired, or calcined metal oxide or metal carbide containing [e.g., porcelain, brick, cement, etc.]
• CPC Class Codes: Y10T 428/161 with frame, casing, or perimeter structure
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

The invention concerns a window including at least a first sheet (16), a second sheet (18), said sheets being joined together by a connecting layer (20), characterised in that it also includes an ultrasonic device (12) placed between said sheets (16,18) and co-operating directly with a first face (24) of said first sheet (16) to detect the presence of foreign bodies on a second face (26) of said first sheet (16) opposite said first face (24), said device (12) comprising a transducer (28) able to emit, via a transmitting/receiving face, an incidental ultrasonic signal of wavelength λ in said first sheet (16), the thickness of said first sheet being equal to K.λ/2, where K is an integral number, and said transducer being able to receive, via said transmitting/receiving face a reflected ultrasonic signal representative of the presence or absence of said foreign bodies to generate a detection signal.

Claims

1. A window comprising at least a first sheet (16), a second sheet (18), said sheets being joined together by a connecting layer (20), an ultrasonic detection device (12) being placed between said sheets (16, 18) and co-operating directly with a first face (24) of said first sheet (16) to detect the presence of foreign bodies on a second face (26) of said first sheet (16) opposite said first face (24), said device (12) comprising a transducer (28) able to emit, via a transmitting/receiving face, an incidental ultrasonic signal of wavelength λ

in said first sheet (16), the thickness of said first sheet being equal to K.λ

/2, where K is an integral number, and said transducer being able to receive, via said transmitting/receiving face, a reflected ultrasonic signal representative of the presence or absence of said foreign bodies to generate a detection signal.

2. A window according to claim 1, wherein the connecting layer (20) Comprises a recess (22) in which extends said ultrasonic detection device (12).

3. A window according to claim 2, wherein the second sheet (18) comprises a through opening (38) which extends approximately facing said recess.

4. A window according to claim 3, wherein said opening (38) is closed by a cap (42).

5. A window according to claim 4 in which said ultrasonic detection device comprises a piezoelectric transducer (28) provided with electrodes (30,32) and conductors (34,36) connecting said electrodes (30,32) to a detection circuit, wherein said conductors (34,36) extend across the cap (42) in order then to extend over a face (44) of the second sheet (18).

6. A window according to claim 2, wherein said 34 recess (22) is closed by the second sheet (18).

7. A window according to claim 6, wherein said detection device (12) is placed in a spacer forming a case (50) whose base (52) is partially cut away, said spacer being supported between the first and the second sheet (16,18).

8. A window according to claim 1, wherein said detection device (12) is fixed onto said first face (24) by means of a film of glue (40).

9. A window according to claim 1, wherein said detection device (12) is fixed onto said first face (24) by welding

10. A window according to claim 1, wherein said first sheet (16) is of a first thickness and in that said second sheet (18) has a second thickness different from said first thickness.