Torque Converter Patents: Who Leads, Where the Gaps Are 2026
- 46.5% concentration. The top 5 assignees alone account for 2,184 of the 4,693 records in scope — nearly half the field sits with a handful of drivetrain majors.
- Filing has cooled from its 2017 peak. 234 records published that year against 3 so far in 2026, with a -66% drop from 2021 (62) to 2024 (21), the last complete year in this data.
- F16H dominates, but control layers are catching up. 73.5% of records touch core gearing (F16H), while hybrid vehicle control (B60W) and clutch hardware (F16D) each sit near 17%, pointing to where new claims are actually landing.
Filing growth compares 2021 (62 records) with 2024 (21) — a three-year span. 2024 is the most recent year we treat as complete: publication lags filing by roughly 18 months, so 2025 onwards are still filling in and any growth rate that ends there would understate the field. Top-5 share is the combined record count of the five largest assignees divided by all 4,693 records in scope (CR5), not by the ranked leaders only.
What this landscape covers
This landscape draws on 4,693 published patent records filed between 2015 and mid-2026 that combine hydrodynamic torque converter or fluid coupling architecture with control-side claims — stall torque ratio management, converter slip, impeller blading, lockup clutch actuation, thermal capacity, or torsional damping. The scope is deliberately narrow: it excludes generic transmission filings that do not touch these specific mechanisms, so the records here are the ones actually contesting torque converter design and control space.
Because publication lags filing by roughly 18 months, the last one to two years in any trend chart will always look thinner than they eventually turn out to be. Read the 2024 figures as the most recent complete signal, and treat 2025-2026 as still filling in.
Filing trends and technology composition
Two views of the same 4,693 records: how filing volume has moved year over year, and which IPC subclasses carry the claims.
A field past its filing peak
Filings peaked at 234 in 2017 and have declined since; the 2021-to-2024 span alone shows a -66% drop, from 62 to 21 records. That is a real slowdown in new filing activity, not an artifact of the data cut-off, since 2024 is the last year with a complete publication window.
Core gearing still anchors the field
F16H (gearing and transmissions) appears in 73.5% of the 4,693 records, far ahead of any other class. Hybrid vehicle control (B60W, 17.4%) and clutch and brake hardware (F16D, 17.3%) are the next densest layers, with vibration damping (F16F, 8.0%) and electric propulsion (B60L, 3.4%) trailing — a sign that control-software and electrification claims are still a minority share of this corpus.
Shares are the percentage of the 4,693 records in scope. A patent can carry several IPC classes, so the shares add up to more than 100%.
Go deeper on Torque Converters and Hydrodynamic Drives with Eureka
This page is one run against one query. Ask Eureka your own question about torque converters and hydrodynamic drives and every answer comes back with the patent numbers behind it.
Try EurekaA representative filing and the most-cited prior art
Hydraulic Control System for a Hydrodynamic Torque Converter Comprising a Controlled Torque Converter Lockup Clutch
Filed by ZF Friedrichshafen, this 2008 application describes a hydraulic control system that governs the supply pressure to a torque converter and, separately, to its lockup clutch, engaging the lockup clutch once the converter's supply pressure drops below a set threshold relative to the clutch's own supply pressure. A converter pressure valve regulates the converter-side pressure.Abstract lightly trimmed for length; reference numerals from the original filing retained.
| # | Publication no. | Patent title | Citations |
|---|---|---|---|
| 1 | US4994078A | Intraventricular artificial hearts and methods of their surgical implantation and use | 356 |
| 2 | US5657625A | Apparatus and method for internal combustion engine control | 298 |
| 3 | US5092879A | Intraventricular artificial hearts and methods of their surgical implantation and use | 223 |
| 4 | US4875391A | Electronically-controlled, adaptive automatic transmission system | 214 |
| 5 | US5562565A | Power transmission system in a hybrid vehicle | 170 |
| 6 | US6152254A | Feedback and servo control for electric power steering system with hydraulic transmission | 163 |
| 7 | US20200339010A1 | Battery thermal management system and method | 152 |
| 8 | JP1992219553A | Multistage automatic transmission for automobile | 146 |
| 9 | US6591705B1 | Transmission | 145 |
| 10 | US6026940A | Lockup clutch with a compensation flywheel mass at the torsional vibration damper | 142 |
Citation counts favour older filings simply because they have had more time to accumulate citations within this corpus — treat them as a signal of influence on the field, not of current commercial relevance.
Each row carries its publication number; clicking a row searches Eureka by that number.
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Three read-outs from the concentration, trend and classification data above.
The field is not open ground
With the top 5 assignees holding 46.5% of all 4,693 records and the top 10 pushing that to 62.9%, a new entrant is filing directly into territory already claimed by established drivetrain and transmission makers. Freedom-to-operate work here needs to start with those incumbents' claim scope, not a general prior-art sweep.
Volume is down from its 2017 high
Filing peaked at 234 records in 2017 and has fallen steadily since, with the last fully comparable window (2021 to 2024) down 66%. That is consistent with a mechanically mature converter architecture where remaining claims cluster around control refinement rather than fundamentally new hardware.
Core gearing claims still dominate
F16H accounts for 73.5% of the 4,693 records, well ahead of B60W and F16D at roughly 17% each. The gap suggests hybrid control-layer and clutch-hardware claims are a secondary, not primary, filing strategy for most assignees in this space, leaving room to differentiate through control logic rather than mechanical redesign.
Eureka can read the same corpus for gaps instead of for coverage: under-claimed branches adjacent to torque converters and hydrodynamic drives, with the prior art for and against each one.
Who holds the ground, and where they have stalled
The ranked leaders are dominated by automakers and transmission specialists who have filed continuously since 2015 — but recent-year momentum data shows even the largest of them recording no new publications in the latest year, a pattern consistent with the broader post-2017 slowdown rather than any single company's retreat.
A single filer well ahead of the field
The leading assignee's 722 records outpace fifth place (195) by more than three-fold, a gap wide enough that its claim portfolio effectively sets the boundary conditions for lockup clutch and converter control design across the rest of the field.
A steep drop-off after the top five
Tenth place holds 134 records against 195 at fifth and 722 at the top — the ranking thins out quickly, and most of the 100 ranked companies sit well below this threshold with far smaller, more specialised filing footprints.
Filing runs largely through corporate family structures
The strongest co-assignee links sit between a parent automaker and its transmission subsidiary, reflecting internal group filing rather than cross-company joint development. External collaboration between unrelated assignees is not a visible pattern in this dataset.
| Assignee | Recent year | YoY |
|---|---|---|
| Toyota Motor Corporation | 0 | -100% |
| Allison Transmission, Inc. | 0 | -100% |
| Aisin AW Co., Ltd. | 0 | — |
| ZF Friedrichshafen AG | 0 | — |
| General Motors LLC | 0 | — |
| BorgWarner Inc. | 0 | — |
| GM Global Technology Operations LLC | 0 | — |
| LuK Antriebssysteme GmbH | 0 | — |
Where to take this analysis
The dataset points to a mature, control-layer phase of filing. These are the natural next steps for a team acting on it.
Map claim scope against the leading assignee
With one filer holding 722 records and the next tier trailing well behind, freedom-to-operate work should start by scoping that portfolio's lockup clutch and converter control claims before drafting anything new.
Run a claim comparison in EurekaTrack the control-layer shift
B60W and F16D claims are approaching the density of core F16H filings, suggesting future differentiation will happen in control logic rather than converter hardware.
Watch this technology in EurekaValidate white space before drafting
Thermal capacity modelling and adaptive stall-ratio control show thinner filing density than the mechanical core — worth confirming with a targeted search before committing drafting resources.
Search this white space in EurekaCommon questions on this landscape
The assignee ranking in this dataset is led by a single company with 722 records, well ahead of the fifth-ranked assignee at 195. The leaders are predominantly automakers and transmission specialists that have filed continuously across the 2015-2026 window, and the top 5 combined account for 46.5% of all 4,693 records in scope. Anyone assessing freedom to operate should treat that leading portfolio as the primary reference point rather than the field average.
Filing peaked at 234 records in 2017 and has declined since, with the last fully comparable window showing a 66% drop from 62 records in 2021 to 21 in 2024. Because publication lags filing by roughly 18 months, 2025 and 2026 figures are still incomplete and should not be read as confirming further decline. The trend through 2024, however, is a genuine slowdown rather than a data artifact.
Core gearing and transmission claims (F16H) appear in 73.5% of the 4,693 records, making it by far the densest classification. Hybrid vehicle control (B60W) and clutch and brake hardware (F16D) each sit around 17%, with vibration damping, engine control and electric propulsion classes trailing further behind. Because records often carry multiple IPC classes, these shares add up to more than 100% and should be read as overlapping coverage rather than a strict breakdown.
The densest claim territory is mechanical converter and clutch hardware under F16H and F16D, which leaves comparatively thinner coverage in areas like thermal capacity modelling, software-defined lockup clutch scheduling, and adaptive stall torque ratio control. These sit closer to the control-software layer than to core hardware, which is consistent with the broader shift in filing activity toward B60W-classified claims. A targeted search against the current portfolio of the leading assignees is the right next step before drafting in these areas.
This ZF Friedrichshafen filing describes a hydraulic control system that manages separate supply pressures to a torque converter and its lockup clutch, engaging the lockup clutch once the converter-side pressure falls below a defined threshold relative to the clutch's own supply pressure, using a dedicated converter pressure valve. It is a control-architecture patent rather than a converter hardware patent, so it primarily constrains how lockup engagement timing and pressure sequencing can be implemented. Designing around it typically means using a different triggering logic or pressure-sensing arrangement rather than a different converter structure.
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Disclaimer. This page is generated from Patsnap Eureka data drawn from a limited snapshot of global patent and scientific-literature records, and is provided for general information and reference only.
Patent data carries inherent limitations: recent filings (typically the most recent 18–24 months) are under-counted due to standard publication lag; counts may be reported at either a patent-family or a patent-record basis and are not always directly comparable; classification, applicant-name, and citation data may contain errors, duplicates, or omissions; and the underlying search query defines and constrains the scope shown. As a result, the analysis may be incomplete or inaccurate and may not reflect the full technology landscape.
Nothing on this page constitutes an exhaustive prior-art, novelty, freedom-to-operate, or validity search, nor does it constitute legal, financial, investment, or professional advice, and it should not be relied upon as such. Any patent, commercial, or strategic decision should be verified independently and reviewed with qualified patent, legal, and domain professionals. Patsnap makes no warranties, express or implied, as to the accuracy, completeness, or fitness for any particular purpose of the information presented.
Machine translation. Assignee and organisation names originally recorded in Chinese, Japanese or Korean have been rendered into English by an AI translation step so that the tables stay readable. These renderings are best-effort and may not match a company’s registered English name; the original name is what the underlying patent record carries, and it is what any Eureka query launched from this page uses.