What the patents claim
Claim 1 of US 10,322,615 recites a vehicle with independently adjustable front and rear suspension, a detector that reports a roadway defect ahead of the front wheel, and processing circuitry that uses vehicle motion data and the detector signal to time an adjustment to the rear suspension before the rear wheel reaches the defect.
The sibling patents vary the sensor: a transmitter with reflection sensors at the tires (’020), predicted wheel contact times from reflected electromagnetic waves (’158), and a camera that images the road ahead (’454).
What we found
Nissan’s US 4,717,173 (priority March 1987) has independently adjustable front and rear damping, a road sensor ahead of the wheels, and a controller that hardens the suspension after a delay time when a bump or hole is recognised. That maps onto the front/rear arrangement, the roadway-defect detector and the rear-wheel timing of the ’615 claim.
Mitsubishi’s US 5,347,457 (priority September 1990) uses a forward road-surface sensor and vehicle speed to calculate the moment the wheel reaches an irregularity, and changes spring or damper rigidity at that moment. Mitsubishi’s US 5,450,322 (1994) does the same with a sensor reading the road a set distance ahead.
None of the three appears in the citation lists of the Enpulz patents or their family. The examiner did see other preview-suspension art (Fuji, Lucas and a different Nissan patent), so the field was not unknown; these specific references were not before the office.
Why it matters to the defendants
The same family is asserted against four automakers, so one set of references serves every defendant. The two oldest references predate the Enpulz priority date by 17 to 20 years, and together they cover most elements of the three sensor-based claims. The camera claim (’454) is the weakest fit: a 1993 camera-based vehicle warning patent supplies the camera and driver alert, but not the suspension change.
The answer in Patent Mechanics
The search as it appears in the app, abridged.
| Reference | Assignee | Priority | Citation record | Fit |
|---|---|---|---|---|
| US 4,717,173 | Nissan | 1987 | Not cited | Strong |
| US 5,347,457 | Mitsubishi | 1990 | Not cited | Strong |
| US 5,450,322 | Mitsubishi | 1994 | Not cited | Partial |
| Element | Claim language (abridged) | ’173 | ’457 |
|---|---|---|---|
| 1[a-b] | Independently adjustable front and rear suspension | ✓ | ? |
| 1[c] | Detector for a roadway defect ahead of the front wheel | ✓ | ✓ |
| 1[d] | Vehicle motion data and detector signal received in advance | ? | ✓ |
| 1[e] | Timed adjustment of the rear suspension | ✓ | ✓ |
References
| Reference | Title | Priority | Covers | Gaps |
|---|---|---|---|---|
| US 4,717,173 | Suspension control system for automotive vehicle (Nissan) | 1987-03-09 | Independent front and rear damping; road sensor ahead; delayed hardening when a bump is recognised | Use of vehicle motion data to be confirmed in the full text |
| US 5,347,457 | Controlling suspension when the wheel reaches an irregularity detected ahead (Mitsubishi) | 1990-09-18 | Forward sensor plus vehicle speed; computes arrival time; changes rigidity then | Separate front and rear sensors not confirmed |
| US 5,450,322 | Suspension control system (Mitsubishi) | 1994-04-15 | Road sensor a set distance ahead plus speed sensor; adjusts suspension | Rear-wheel timing not in the claims |
Limits of this analysis
- First-pass reading of claims and abstracts; element-by-element claim charts against the full texts are the next step.
- Late-1980s and 1990s preview-suspension products from the defendants themselves may be stronger evidence than patents and are outside this search.
“Not cited” means the reference does not appear in the examiner or applicant citations of the patent or its family in our index. This article is research, not legal advice, and makes no finding that any claim is invalid.
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