WHEEL SPEED SENSOR FOR AN ADAPTIVE BRAKING SYSTEM

• US 3,626,227 A
• Filed: 06/01/1970
• Issued: 12/07/1971
• Est. Priority Date: 06/01/1970
• Status: Expired due to Term

• Current Assignee: Irving R. Ritsema
• Original Assignee: Irving R. Ritsema
• Inventors: Ritsema, Irving R.
• Primary Examiner(s): Sliney, D. X.
• Assistant Examiner(s): Skudy, R.
• Application Number:
  US05/042,181
• Time in Patent Office: 554 Days
• Field of Search: 310/79-82,168-171,112,114,90,120,121 73/529 74/11-13 324/174 179/1.2T 295/36,43 102/61,217,118,215C 108/55 317/5 303/20,21
• US Class Current: 310/168
• CPC Class Codes: B60T 8/329 Systems characterised by their speed sensor arrangements
• CPC Class Codes: G01P 3/488 delivered by variable reluctance detectors

Abstract

The tone wheel and the electromagnetic pickup are mounted with a running clearance less than the known deflections which occur during severe braking. Both elements are provided with smooth abrasion resistant bearing surfaces and the pickup is spring mounted so that no damage results during the occasional brief rubbing contacts. The projecting elements of the pole piece of the pickup are covered to a predetermined depth by the bearing material so that a minimum clearance is maintained during the periods of contact.

Claims

1. A wheel speed sensor for an automotive vehicle equipped with an adaptive braking system and having vehicle wheels and wheel supporting means, comprising:

a tone wheel;

means for mounting the tone wheel on a vehicle wheel;

pickup means connected to said wheel supporting means for generating a signal representative of the velocity of said vehicle; and

means for mounting the pickup means in close proximity to said tone wheel;

said mounting means including a resilient element, said resilient element being a leaf spring.

2. The wheel speed sensor of claim 1 in which the resilient element is a leaf spring constructed and arranged to act as a support and guide for the pickup means.

3. The wheel speed sensor of claim 2 in which said tone wheel has teeth and a bearing surface adjacent said teeth.

4. The wheel speed sensor of claim 3 in which said pickup means includes a pole piece with projecting teeth and bearing means surrounding said teeth and extending a predetermined distance beyond said teeth.

5. The wheel speed sensor of claim 1 in which the tone wheel has teeth and a bearing surface adjacent said teeth;

and said pickup means includes a pole piece formed with projecting teeth and bearing means surrounding said teeth and extending a predetermined distance beyond said teeth.

6. The wheel speed sensor of claim 1 in which the pickup means includes:

a pole piece with projecting teeth; and

bearing means surrounding said teeth and extending a predetermined distance beyond said teeth.

7. The wheel speed sensor of claim 5 wherein, during deflection of said wheel with respect to said wheel supporting means, said bearing means contacts said bearing surface to protect the teeth in said tone wheel and said pole piece of said pickup means, said protection of said bearing means and surface allowing said pickup means to be positioned in close proximity to said tone wheel without damage to said wheel speed sensor.

8. The wheel speed sensor of claim 4 wherein, during abnormally large deflections of said wheel with respect to said wheel supporting means, said bearing means contacts said bearing surface and pushes said pickup means inwardly against a counter force from said leaf spring thereby protecting the wheel speed sensor against damage and allowing a closely adjacent relationship between the teeth of said tone wheel and said pickup means which insures against the loss of signals to said adaptive braking system.

9. In a wheel speed sensor for an automotive vehicle equipped with an adaptive braking system and having vehicle wheels and wheel supporting means:

a tone wheel;

means for mounting the tone wheel on a vehicle wheel;

pickup means for generating a signal representative of the velocity of said vehicle; and

a generally C-shaped resilient element carried by said wheel supporting means and presenting a pair of arms movable relative to said wheel supporting means, said arms defining an opening therebetween;

said pickup being mounted within said opening and secured to each of said arms.