US 142340

Let me run additional targeted searches.

US Patent 142,340 — Search Summary

Search results

• USPTO/Google Patents: No independent web result contradicting the supplied full-text record was found. The authoritative record (as supplied) is from Google Patents at https://patents.google.com/patent/US142340/en.
• CAFC 2026 dockets: Searches for "142,340" / "142340" in CAFC 2026 dockets returned no results — which is expected. The patent expired by 1890 (status: "Expired – Lifetime"), roughly a century before the Federal Circuit's 1982 creation, so no CAFC 2026 litigation involving this patent is plausible.
• One caution on ID reuse: A search hit shows that the alphanumeric string US142340A was also used as a USPTO application serial number for a 1961 filing (later issued as US3168683A, "Control unit structure," filed 1961-10-02). That is a different, unrelated filing — application serial numbers are recycled. Do not conflate it with patent US142,340. No evidence ties patent 142,340 to that later application.

Patent record (from supplied authoritative text)

Abstract (plain-language reconstruction; no formal abstract appears in the record)

A chemical fire-extinguisher in which a main reservoir holds a saturated solution of bicarbonate of soda, and a glass acid-reservoir (e.g., for sulphuric acid) is suspended on a shaft inside a cage or basket attached to a top plate. The acid-reservoir normally seats on a fixed stopper/plug. When the extinguisher is inverted for use, the entire weight of the machine bears on the head of the shaft, driving the shaft inward and lifting the acid-reservoir off its stopper; the acid then escapes into the soda solution, evolving carbonic-acid gas in quantity, which pressurizes and impregnates the water for discharge.

Claims overview

The supplied OCR text is partially garbled, so claims 1–2 cannot be quoted verbatim with confidence. What is recoverable:

• Claim 3 (verbatim from record): "The combination of the annular groove b upon the shaft B of the acid-reservoir, the retaining-trigger c, and the spring E, substantially as and for the purpose set forth." — i.e., the trigger/groove latch that holds the shaft retracted (reservoir seated on its stopper during filling/idle) plus the spring that acts against the cross-bar, operating substantially as described.
• Claims 1–2: Not fully legible in the supplied OCR. Based on the specification and the inventor's stated distinction, they appear directed to (1) the overall extinguisher combination — main reservoir containing the soda solution, the plate, packing-box, shaft with head and annular groove, retaining-trigger, cross-bar/supports/clamps engaging the acid-reservoir's groove, the enveloping cage/basket with diaphragm and fixed stopper/plug, and spring — and (2) the structural sub-combination of the shaft-and-reservoir mounting (plate a, shaft B, cross-bar B′, supports C, semicircular clamps C′, cage D, diaphragm D′, stopper d, spring E). I flag these reconstructions as inferences from context, not verbatim claim text.

Key inventive point (per the specification)

Hughes expressly disclaimed novelty in gas generation itself, and acknowledged that prior acid-reservoir plugs had been removed "by screws and various devices." His asserted novelty: an extinguisher in which the stopper/plug of the acid-reservoir always maintains the same relative position to the main reservoir, while the acid-reservoir itself is removed from its plug by the weight of the machine acting on the free end of its shaft B.

Uncertainty notes

• The original full claim language for claims 1 and 2 is not fully recoverable from the OCR supplied; only claim 3 is verbatim.
• No CAFC docket record exists for this patent number; the search tool returned no matching docket entries, consistent with the patent's 1890 expiration.

Litigation Search Results for US Patent 142,340

No known litigation involving US patent 142,340 (US142340A).

Details

US patent 142,340 — "Improvement in chemical fire-extinguishers" — was issued to Alexander E. Hughes of Louisville, Kentucky (assignor of one-eighth to Edward Ford) on September 2, 1873, based on an application filed June 19, 1873. The patent relates to an acid-reservoir release mechanism for a chemical fire extinguisher (soda-acid type), with claims directed to the combination of the shaft, cross-bar, supports, clamps, cage, diaphragm/stopper, trigger, and spring.

Search methodology and findings:

• Searches of litigation-oriented databases and case aggregators (including Unified Patents' litigation portal, CourtListener, and CAFC/Justia case law results) returned no district-court complaints, IPR/PGR proceedings, PTAB matters, or Federal Circuit appeals naming US 142,340 as the patent-in-suit.
• The searches surfaced only incidental, non-substantive hits:
  • Google Patents' own record for US142340A (status: Expired – Lifetime, with an anticipated expiration date of September 2, 1890).
  • An unrelated 1961 application that happened to share the serial number "US142340A" (later issued as US3168683A, a control-unit structure patent) — this is a different document and is not the 1873 Hughes patent.
  • Various modern Unified Patents/PTAB cases involving wholly unrelated patents (e.g., '431, '949, '924, '361 patents), none of which reference patent 142,340.
• No historical (19th- or early 20th-century) infringement suits against this patent were located in the searched sources either.

Conclusion

For context: the patent expired in 1890, and no modern enforcement is plausible because the patent is more than 150 years old and long since expired. If you intended a different patent (e.g., a modern number that merely shares digits or contains "142,340" as an application/patent-family component), please provide the corrected number and I will re-run the litigation search against that identifier.

Proceedings overview

Total AIA trial proceedings on file: 0 — no IPR, PGR, or CBM petitions have ever been filed against US 142,340 (breakdown: 0 active, 0 with claims invalidated, 0 with claims sustained, 0 settled, 0 institution denied). This is not a gap in the USPTO Open Data Portal ingest; it is a logical certainty. The patent issued 1873-09-02, expired 1890-09-02, and was dead for 121 years before the America Invents Act created inter partes review (effective 2012-09-16). The PTAB did not even exist in its current form when this patent's term ended. The defensive posture this gives a defendant is absolute and structural: the patent is expired and unenforceable — no AIA trial can ever be instituted against it, and no demand letter premised on it can support relief of any kind.

Web searches for US142340A/"142,340" combined with IPR/PGR/PTAB terms, and for PTAB E2E proceeding records, return no proceedings. The only hits are noise: unrelated Justia inventor pages (other "Alexander Hughes" inventors) and a later-issued chemical fire-extinguisher patent (US179894) that references the same art area but is not a PTAB proceeding.

No proceedings to report

There are no AIA trial proceedings (IPR/PGR/CBM) on US 142,340 to summarize at claim level, and none can exist. The governing statutory screens confirm why:

• Eligibility — 35 U.S.C. § 311 (IPR) and § 321 (PGR): A petition may only challenge a patent under the AIA framework. US 142,340 issued under the 1873 patent laws, predating even the 1952 Act. AIA trial eligibility attaches to patents by virtue of the statutory framework enacted in 2011-2012; a patent that expired in 1890 is categorically outside it.
• Standing — 35 U.S.C. § 315(b): An IPR petition must be filed within one year of service of a complaint alleging infringement. No complaint alleging infringement of US 142,340 has been served since 1890 (or ever, in the modern era), and the limitations period on any such claim expired roughly a century ago.
• Realistic impossibility: Even setting aside standing, no petitioner has ever existed who could be estopped, injured, or motivated to challenge a patent that has been in the public domain since the administration of Benjamin Harrison.

Defensive value: For anyone receiving a demand letter referencing US 142,340, the response writes itself — the patent's term expired 1890-09-02 (status on file: "Expired – Lifetime"), it is unenforceable, and no PTAB proceeding was needed to reach that result because no PTAB proceeding was ever possible.

Strategic summary

Claim-level status. No claims of US 142,340 are "canceled" by PTAB action, and none are "sustained" by a Final Written Decision — because no petition was ever filed. All three claims (claim 3 verbatim; claims 1–2 recoverable only in reconstructed form from the garbled OCR of the specification) are in the public domain by operation of law. The patent's 17-year term from issue date ended 1890-09-02. From a defensive standpoint, every claim — independent and dependent alike — is unassertable today. This is strictly stronger than any IPR outcome: an IPR can only invalidate claims or leave them standing; it cannot resurrect an expired patent, and conversely nothing about a patent owner's PTAB loss record matters here because there is none.

Estoppel landscape — § 315(e)(2). The estoppel question is moot. There are no petitioners, no privies, and no grounds that were or could have been raised, because no AIA trial was ever available. For a defendant being "asserted against" today, the operative doctrines are not IPR estoppel but: (1) expiration — the patent confers no right to exclude after 1890-09-02; (2) laches / statute of limitations — any infringement claim is barred by a margin of well over a century; and (3) unclean hands / Rule 11 exposure for anyone sending an enforcement letter on a patent that expired before the invention of the modern fire extinguisher industry it purports to cover.

Pattern signals. No petitioner has filed multiple IPRs; no defensive aggregator (Unified Patents, etc.) appears in any chain; no patent owner has "pursued PTAB appeals" because there are no PTAB decisions to appeal. The absence of proceedings is itself the only signal, and it is fully explained by the patent's 19th-century vintage rather than by litigation strategy. The one genuine caution flag from earlier research stands: the alphanumeric string US142340A was recycled by the USPTO as an application serial number for a 1961 filing (issued as US3168683A, "Control unit structure") — that unrelated filing must not be mistaken for this patent in any database cross-search.

Recommended next steps

• If you are the defendant: Do not litigate — respond with a one-page letter. State that US 142,340 expired 1890-09-02 by operation of its statutory term and is recorded "Expired – Lifetime" on the USPTO/Google Patents record (https://patents.google.com/patent/US142340/en). Demand withdrawal of the demand letter and a covenant not to sue, and put the sender on notice of potential fee-shifting and Rule 11 sanctions for asserting an unenforceable, 150-year-old patent. There is no PTAB FWD to link because no FWD exists.
• Do not file an IPR/PGR/CBM as a "defense": It would be dismissed as ineligible — the petition would fail threshold review because the patent is not subject to AIA trial and no § 315(b) one-year window has ever opened. Filing one would waste money and invite sanctions for a frivolous petition.
• Verify before relying on this: The "no PTAB activity" default rests on the USPTO ODP structured data in this prompt (no AIA trials on file) and on web searches returning no proceedings. If a third-party database ever surfaces a proceeding number tied to "US142340," first check whether it references the recycled 1961 application serial number (US3168683A family) rather than this 1873 patent — the two share only an alphanumeric string, not a legal identity.
• Preserve the record: Save the Google Patents record page and a screenshot of the status field. If the sender's theory depends on a reissue, continuation, or foreign counterpart, demand production of the actual instrument — no reissue or continuation of an 1873 patent could extend enforceable rights past the 1890s under the law then in force.

Bottom line: There is no PTAB war to win here because there is no war. US 142,340 is a museum piece — expired for 136 years as of today (2026-09-09), with zero AIA trial history and zero possibility of one. Any assertion of it is legally frivolous on its face.

I'll research the assignment record for US patent 142,340 by querying available sources.

Based on my searches, I need to be transparent about what can and cannot be verified. The web searches I ran (USPTO assignment database indexes, Google Patents, and general web for Hughes/Ford assignment records) all returned no results, and the USPTO Assignment Center was not directly reachable in this session. Here is the reconstruction with that caveat clearly stated.

Inventors

Pattern notes: Single inventor, no co-inventor constellation to analyze, and no evidence of any employment relationship at filing. The only co-interest holder at issuance, Edward Ford of New Albany, Indiana (one-eighth assignee), is not an inventor — he appears purely as a partial assignee/financier. There is no data from which to infer post-filing departure from any corporate employer, because no corporate employer is identified anywhere in the record.

Original assignee

• Entity named on the issued patent: The patent issued to Alexander E. Hughes as patentee. The face of the patent recites that Hughes was "assignor of one-eighth (⅛) his right to Edward Ford, of New Albany, Indiana." Hughes therefore retained the remaining seven-eighths interest at issuance; Ford held a one-eighth undivided interest.
• Product embodying the claims: Not determinable from the record. The specification describes a soda-acid chemical fire-extinguisher with an invert-to-activate acid-reservoir release; whether Hughes or Ford ever commercially shipped such a device is unrecorded in the sources available to me.
• Primary line of business: Not determinable. Hughes is identified only as an inventor of Louisville; Ford only as a resident of New Albany, Indiana.
• Current status: Both individuals are long deceased; the patent itself shows "Expired – Lifetime" with anticipated expiration September 2, 1890 (the then-standard 17-year term from issue).

Assignment timeline

The USPTO Assignment Center contains no searchable records for US 142,340 — I could not locate any reel/frame entries for this patent, and no web-indexed source surfaced any recorded assignment for it. I will not fabricate reel/frame numbers.

This absence requires careful interpretation rather than a quick "no assignments" conclusion:

1. Only assignment known to exist: the partial conveyance recited on the face of the patent itself — Hughes → Ford, one-eighth (⅛) of the right — acknowledged at issuance (patent dated 1873-09-02; application filed 1873-06-19). That conveyance is evidenced by the patent imprint, not by any reel/frame I can verify.
2. Why the Assignment Center is empty is expected: the USPTO's electronic assignment searchable database does not meaningfully extend to 1873-era recordings. Assignments from the 1870s were recorded in bound assignment volumes with volume/page citations, not the modern reel/frame system, and the vast majority were never digitized into the searchable center. Absence from the Assignment Center is therefore not affirmative evidence that no post-issuance assignments occurred — it is a database-coverage artifact.
3. No corroborating web sources found: searches for the Hughes/Ford assignment, for any reel/frame indexed against "142,340" or "US142340," and for the patent number in assignment indexes all returned zero results. Google Patents' legal-event tab for US142340A likewise shows no recorded assignment events — only the status line "Expired – Lifetime."

Because no recorded assignment chain exists in any accessible source, I am stopping here per the task instruction (the Timeline diagram, NPE/troll-pattern signal analysis, and Verdict sections are not applicable — there is no chain to diagram or score).

Bottom-line finding on ownership

The only ownership fact supported by evidence is the one recited on the patent: as of September 2, 1873, Hughes owned 7/8 and Ford owned 1/8 of US 142,340. No subsequent conveyance was located. Whatever happened to the two interests after 1873 is unrecorded in every source I could reach, and any rights terminated no later than the patent's expiration on September 2, 1890. For verification purposes, the authoritative public record is Google Patents at https://patents.google.com/patent/US142340/en; the USPTO Assignment Center (https://assignmentcenter.uspto.gov/) may be checked directly by patent number, but based on database coverage and my searches I would not expect it to return 1873-era recordings.

Verification link: https://assignmentcenter.uspto.gov/ (search patent number 142340 — expected result: no recorded assignments; this is a database-coverage limitation for an 1873 patent, not a finding that the original owners retained the patent).

USPTO Database Search — U.S. Patent 142,340

1. Database lookup result (literal ID, no similar numbers)

Searching the identifier 142340 (issued as US142340A) returns exactly one patent record:

Number-hygiene confirmation. As flagged in the prior sections, the alphanumeric string "US142340A" was reused by the USPTO as an application serial number for a 1961 filing that issued as US3168683A ("Control unit structure," filed 1961-10-02). That document is not the 1873 Hughes patent, and it has been excluded from this analysis. No other "similar" patent numbers were conflated in.

2. What the "citation record" for 142,340 actually contains — an important threshold finding

US 142,340 has no formal backward-citation list on record. Specifically:

• The authoritative Google Patents record (fetched 2026-09-09 and supplied in full) contains no "Patent Citations" and no "Non-Patent Citations" section for US142340A.
• The only related-document list the record carries is Google's machine-computed "Similar Documents" tab. That is not an examiner citation list and carries no legal significance as "cited art."
• This is consistent with USPTO practice in 1873: mid-19th-century patents did not print examiner citation lists, and the USPTO's legacy PatFT image record for this patent would likewise show no formal "References Cited" field.

Accordingly, there are no examiner-cited references to enumerate. The correct analytical approach — and the one adopted below — is to treat the pre-filing (before June 19, 1873) items in the "Similar Documents" list as candidate prior-art disclosures, and to supplement them with the prior art admitted in the patent's own specification ("the plugs to the acid-reservoirs have been removed by screws and various devices").

A second important screening point: most of the items Google lists as "Similar Documents" post-date the 1873 filing (e.g., US695235A of 1902, US1452657A of 1923, US1167791A of 1916, US854681A of 1907, etc.). Documents published after June 19, 1873 cannot be § 102 prior art against this patent, so they are excluded from the anticipation analysis and listed only in § 5 below for completeness.

3. Claim set used for the § 102 mapping

Because the OCR of claims 1–2 is partially garbled, the mapping is made against the best-recoverable claim scope, with the same inference flags used earlier:

• Claim 3 (verbatim): "The combination of the annular groove b upon the shaft B of the acid-reservoir, the retaining-trigger c, and the spring E, substantially as and for the purpose set forth." — i.e., a latch sub-combination: a shaft carrying the acid-reservoir, an annular groove on that shaft, a pivoting retaining-trigger engaging the groove to hold the shaft retracted, and a spring acting on the shaft.
• Claims 1–2 (reconstructed from the specification — not verbatim): (1) the full extinguisher combination — main reservoir with bicarbonate-of-soda solution, top plate with packing-box, shaft with head and annular groove, trigger, cross-bar/supports/semicircular clamps engaging a groove on the glass acid-reservoir, enveloping cage/basket with diaphragm and a fixed stopper/plug, and spring; and (2) the shaft-and-reservoir mounting sub-combination (plate a, shaft B, cross-bar B′, supports C, clamps C′, cage D, diaphragm D′, stopper d, spring E).
• Core inventive distinction (per the specification): the stopper/plug always maintains the same relative position to the main reservoir, while the acid-reservoir itself is lifted off that fixed plug by the weight of the machine bearing on the free end of shaft B upon inversion.

Under § 102, a reference anticipates only if it discloses every element of the claim, arranged as in the claim, in a single prior-art document.

4. Candidate prior art that qualifies by date (published before 1873-06-19)

These six documents are the only items on the record's "Similar Documents" list that predate the filing and therefore qualify as § 102-type prior art. Full texts were not retrievable within the search limits of this session, so descriptions are drawn from titles, dates, classifications, and Hughes's own characterization of the state of the art; anticipation conclusions are marked accordingly as provisional.

4.1 U.S. Patent No. 114,775 (US114775A) — "Improvement in acid-bottles for fire-extinguishers" — published May 16, 1871

• Description: The closest subject-matter neighbor on the list: it is directed specifically to the acid-bottle / acid-container release component of chemical fire-extinguishers, the precise problem Hughes addressed. Hughes's own specification concedes that, before him, "the plugs to the acid-reservoirs have been removed by screws and various devices" — this reference is the archetype of that screw/device-release line of extinguisher art.
• Potential § 102 mapping:
  • Claim 1 (reconstructed broad combination): Potentially — if US114,775 discloses a main reservoir, soda solution, an acid reservoir whose plug is released to dump acid, it may read on the broad gas-generation combination. Provisional: plausible for the generic combination elements.
  • Claim 2 (mounting sub-combination): Unlikely — nothing in its title or in Hughes's characterization suggests the specific cage/diaphragm/fixed-stopper/spring mounting in which the stopper stays stationary relative to the main reservoir.
  • Claim 3 (groove + trigger + spring): Unlikely to anticipate — screw-type and "various device" plug removers disclosed in this art would not inherently show the annular groove/retaining-trigger/spring latch triad. No element of claim 3 can be confirmed against it without full text.

4.2 U.S. Patent No. 105,279 (US105279A) — "Improvement in fire-extinguishers" — published July 12, 1870

• Description: An earlier soda-acid-type fire-extinguisher patent predating Hughes by three years; belongs to the same A62C art as 142,340. Likely discloses a main reservoir and a chemical-generation arrangement, though its acid-release mechanism is unknown from the record.
• Potential § 102 mapping:
  • Claim 1 (broad combination): Potentially, for the generic main-reservoir + soda-solution + releasable-acid elements — but only if claim 1 as issued is not limited to the weight-actuated fixed-stopper shaft mechanism.
  • Claim 2: Unlikely (see 4.1).
  • Claim 3: Not indicated — no basis on the record to conclude it discloses an annular groove, trigger, and spring combination.

4.3 U.S. Patent No. 111,877 (US111877A) — "Improvement in fire-extinguishers" — published February 14, 1871

• Description: Second 1871 extinguisher patent on the list; general soda-acid chemical-extinguisher background art contemporaneous with (4.1).
• Potential § 102 mapping: Same pattern as 4.2 — potentially probative against the reconstructed broad claim 1 combination elements; not indicated against the structural claims 2–3 without full-text confirmation.

4.4 U.S. Patent No. 123,783 (US123783A) — "Improvement in fire-extinguishers" — published February 20, 1872

• Description: 1872 chemical fire-extinguisher patent, filed ~16 months before Hughes's application; squarely within the same field and likely representative of the "screws and various devices" plug-removal art that Hughes distinguished.
• Potential § 102 mapping: Potentially against the generic portions of reconstructed claim 1; not indicated against claims 2–3 absent full text.

4.5 U.S. Patent No. 127,770 (US127770A) — "Improvement in fire-extinguishers" — published June 11, 1872

• Description: The most recent qualifying predecessor (about one year before Hughes's June 19, 1873 filing); same extinguisher art; likely shows the state of acid-release mechanics immediately before Hughes.
• Potential § 102 mapping: Potentially the strongest § 102(a)-type candidate against the broad combination of reconstructed claim 1, if that claim is read without the weight-actuated shaft limitation. Claims 2 and 3: no indication from the record that the fixed-stopper/weight-actuated-shaft arrangement or the groove/trigger/spring latch was present; Hughes's specification affirmatively implies the prior plug removers acted on the plug (by screws) rather than lifting the reservoir off a stationary plug.

4.6 U.S. Patent No. 43,703 (US43703A) — "Improvement in measuring-nozzles for liquid-jars" — published August 2, 1864

• Description: The earliest document on the list and the least on-point: a liquid-jar measuring-nozzle patent, not a fire extinguisher. It is machine-listed presumably for structural similarity (stopper/nozzle/shaft arrangements) rather than for subject-matter proximity.
• Potential § 102 mapping: Not indicated against any claim of 142,340. Different field of endeavor and, on the record, no disclosure of an acid reservoir, soda solution, gas generation, or extinguisher combination. It could at most be a § 103-type structural analogue for a plug-releasing shaft — not an anticipatory reference for any claim.

4.7 Admitted prior art in the specification (non-patent disclosure)

• Description: Hughes expressly states: "I am aware that in the construction heretofore of chemical fire-extinguishers the plugs to the acid-reservoirs have been removed by screws and various devices…" This is a specification admission that plug-removal-by-screw (and similar mechanical plug-removal devices) in soda-acid extinguishers was known before June 1873.
• Potential § 102 mapping: As an admission, it supports treating the screw-type plug-removal extinguishers (typified by 4.1/4.4/4.5) as prior art against the generic acid-release concept in reconstructed claim 1, while simultaneously defining the gap Hughes claimed to fill — the fixed-stopper/weight-actuated-reservoir arrangement of claims 2–3 — which the admitted art did not show.

5. Documents on the record that are NOT § 102 prior art (published after 1873-06-19) — excluded

For completeness, the remaining "Similar Documents" items all post-date the filing and therefore cannot anticipate US 142,340: US150262A (1874), US147249A (1874), US148526A (1874), US149331A (1874), US186707A (1877), US230167A (1880), US264039A (1882), US373919A (1887), US612094A (1898), US628058A (1899), US668998A (1901), US675103A (1901), US695235A (1902), US769021A (1904), US854681A (1907), US1062463A (1913), US1138553A (1915), US1167791A (1916), US1452657A (1923). Several are interesting as later evidence of the field (e.g., US147249A and US148526A, both Feb–Mar 1874 "Improvement in fire-extinguishers," show the immediate follow-on art), but they are irrelevant to § 102 for this patent.

6. Bottom line

1. No formal cited prior art exists for US 142,340 — 1873-era patents carry no examiner citation lists, and the Google Patents record confirms the absence of a "Patent Citations" section.
2. The only date-qualifying § 102 candidates on the record are US114775A (1871), US105279A (1870), US111877A (1871), US123783A (1872), US127770A (1872), and US43703A (1864). Of these, US114775A (acid-bottles for fire-extinguishers, May 16, 1871) is the most relevant by subject matter, and US127770A / US123783A are the closest in time.
3. On the available (title/date/specification-admission-level) evidence, the strongest anticipation risk is against the broad, reconstructed claim 1; the narrow claim 3 (annular groove + retaining-trigger + spring) and the structural claim 2 (fixed stopper with weight-lifted reservoir) appear to be the elements that distinguish over this pre-1873 art — which is exactly the distinction Hughes himself drew in the specification.
4. Confidence caveat: full texts of US114775A, US105279A, US111877A, US123783A, US127770A, and US43703A were not retrievable within this session's search limits, so the per-claim anticipation conclusions above are provisional assessments from the record's metadata plus the patentee's own characterization of the prior art, not verified element-by-element comparisons. If an element-by-element § 102 opinion is required, each of those six specifications should be pulled from the USPTO image database and checked against the three claims.

Statutory note: For an 1873 patent the operative law was the Patent Act of 1870, not the 1952 codification; "§ 102 anticipation" is used here as the standard modern analytical frame per your instruction, and a strict anticipation holding would in any event require single-reference disclosure of every claim element.

I'll ground this § 103 analysis in the actual prior-art records. Let me first pull the disclosures of the key references identified on the patent's "Similar Documents"/prior-art list, plus a few period references.

Let me pull details on the remaining key references from the patent's prior-art list (US123,783; US127,770; US114,775) and related soda-acid extinguisher patents of the period.

Obviousness Analysis — US Patent 142,340 ("Improvement in Chemical Fire-Extinguishers," Hughes, issued Sept. 2, 1873)

0. Scope, evidentiary, and doctrinal caveats (read first)

Three caveats bound the reliability of what follows:

1. Claim text is only partially recoverable. Claim 3 is verbatim in the record. Claims 1 and 2 are reconstructions flagged in the earlier Patent Summary as inferences from the specification. My obviousness analysis of claims 1–2 is therefore contingent on that reconstructed language and should be treated as conditional.
2. Operative doctrine. The patent issued under the Patent Act of 1870, fourscore years before § 103 was enacted in 1952. The functional 1873 analogue was the judge-made "invention" requirement of Hotchkiss v. Greenwood, 52 U.S. 248 (1850), which § 103 codified. I apply the modern § 103/Graham/KSR framework because that is the task assigned, noting that the conclusion would be the same under the Hotchkiss standard: a mere "union of old elements . . . so obvious" as to lack invention.
3. Prior-art content verification. I verified full disclosures for only two references (US 105,279 Van Dyne; US 111,877 Sander). Three additional references from the patent page's "Similar Documents" list (US 114,775; US 123,783; US 127,770) are known only by bibliographic entry/title, and I do not attribute teachings to them that I could not verify. One contemporary commercial/patent system (Carlier & Vignon / Babcock) is known through a period encyclopedia account and an 1870s reported decision, which I cite as such.

1. The claimed invention, reduced to its operative differences

The specification's own novelty statement is the single most useful document for a § 103 analysis, because it concedes the state of the art and identifies the only asserted differences:

"I am aware that in the construction heretofore of chemical fire-extinguishers the plugs to the acid-reservoirs have been removed by screws and various devices; but I am not aware that any extinguisher has been constructed wherein the stopper to the acid-reservoir always maintains the same relative position to the main reservoir as in this my invention, while the acid-reservoir itself is removed from its plug by the weight of the machine upon the free end of its shaft B."

Hughes expressly disclaimed novelty in (a) the soda-bicarbonate/sulphuric-acid chemistry, (b) CO₂ evolution, and (c) pressurization/impregnation of the water. The residue of the invention is mechanical, and the only asserted distinctions are:

• D1 — Geometry: the stopper/plug d is fixed relative to the main reservoir (mounted on diaphragm D′ in cage D), and the acid vessel C — rather than the stopper — is moved off the plug.
• D2 — Actuation: release is effected by the weight of the entire machine, transmitted through the protruding head b of shaft B when the extinguisher is set down inverted, driving the shaft inward (through packing-box a′ in plate a) and lifting the glass reservoir C off its stopper.
• D3 — Latching detail (claim 3): an annular groove b′ on the shaft, a pivoting retaining-trigger c, and a spring E, cooperating to hold the shaft in its retracted (filling) position and to reseat the reservoir on the stopper.

2. The person of ordinary skill in the art (PHOSITA)

A PHOSITA in mid-1873 would be a mechanic or "fire-engine"/apparatus maker familiar with: portable soda-acid chemical extinguishers as an established product category (the Babcock/Carlier & Vignon machines were in commercial US use by 1869–1872); pressure vessels and their closures; stuffing/packing boxes; acid-resistant materials (glass, lead); spring-loaded detents and catches; and the well-known bicarbonate + sulphuric acid → CO₂ reaction. The crowded patent record (at least a dozen US extinguisher patents between 1870 and 1873, plus a reported 1870s infringement case listing twenty-six prior US patents in one extinguisher suit alone — Steiner Fire Extinguisher Co. v. City of Adrian, 52 F. 731 (C.C.E.D. Mich. 1891)) shows this was an actively worked, ordinary-skill mechanical field, not a pioneering one.

3. Prior-art inventory (the "Prior Art section" of the record)

A. References whose content I verified

US 105,279 — J. B. Van Dyne, "Improvement in Fire-Extinguishers" (July 12, 1870).
The closest structural reference. Discloses: reservoir A for water/chemicals; flanged collar B with downward cylindrical extension C and a perforated screw-cap D; a screw-plunger G (with packing g, hand-wheel e, head f) passing through the top; a removable cartridge E holding glass acid-bottles c in a case b; a stirrup-piece F carrying the stoppers c′ pressed onto the bottle necks by an elastic band/spring d. Operation: turning the wheel forces the stirrup down, withdrawing the stoppers from the bottles, liberating acid into the prepared water. Notably, Van Dyne states the apparatus "may rest on either end, as desired," and the cartridge is reloadable through the top. Van Dyne thus supplies: glass acid bottles in a perforated cage inside the main reservoir; a top-closure shaft with packing; spring-biased stoppers; relative motion between stopper-assembly and bottle mouths as the release principle; and an invertible, either-end-standing machine.

US 111,877 — E. Sander, "Improvement in Fire-Extinguishers" (Feb. 14, 1871).
Discloses: an acid-chamber D inside a generating tank A; a conical discharge opening F in the chamber bottom closed by a valve H; and an actuator running through stuffing-boxes K in the top closure — side rods J, J′, cross-heads, and operating screw M — explicitly designed so that "no part" of the operating device passes through the acid chamber. It also shows a locking-staple R to secure the operating handle "tightly in any position to prevent accidental displacement." Sander thus supplies: the concept of an actuator shaft passing through a packed top plate into the interior of a CO₂-generating extinguisher to open the acid discharge, plus a positive latch to hold the actuator in its set position.

B. The Carlier & Vignon / Babcock system (US patent of 1869, reissued 1872) — as documented in period sources

The American Cyclopaedia (1870s) account of the Babcock-built machine — corroborated by the structural description in Northwestern Fire Extinguisher Co. v. Philadelphia Fire Extinguisher Co., 18 F. Cas. 394 (C.C.E.D. Pa.) — describes a strong metallic cylinder containing a glass or leaden vessel for sulphuric acid, suspended by pivots below its center of gravity, and retained upright by a stopper held in the vessel's mouth by a rod passing through the hermetically adjusted cover. Removing the stopper lets the vessel invert by its own weight, precipitating acid into the bicarbonate solution. This is highly material: it shows the stopper fixed relative to the main reservoir (held by the cover-rod) while the acid vessel is freed by gravity — precisely the geometry Hughes claimed as novel (D1) — the residual difference being only the actuating trigger (manual stopper withdrawal there; automatic machine-weight-on-shaft here).

C. References known only by bibliographic entry (content unverified — flagged, not relied upon for specific teachings)

• US 114,775 (May 16, 1871), "Improvement in acid-bottles for fire-extinguishers" — the title alone shows dedicated acid-bottle/stopper design for extinguishers was already a recognized sub-art before Hughes.
• US 123,783 (Feb. 20, 1872) and US 127,770 (June 11, 1872), both "Improvement in fire-extinguishers" — same crowded-field corroboration.
• From Steiner v. Adrian, 52 F. 731 (1891): US 102,431 (Pinkham, Apr. 26, 1870, "fire annihilator"); US 131,414 (Stillson & Kley, Sept. 17, 1872, "chemical fire engines"); US 142,637 (Latte, application filed Jan. 6, 1873 — i.e., before Hughes' June 19, 1873 filing — issued Sept. 9, 1873). Under pre-AIA § 102(e)/§ 103 principles, Latte would be citable against Hughes for what it discloses, though I have not verified its content and do not rely on specific teachings from it.

D. Hughes' own admissions as prior-art evidence

The specification concedes that acid-reservoir plugs "have been removed by screws and various devices," and that the gas-generation chemistry "forms no part of this invention." Those concessions narrow the patentable residue to D1–D3 above and frame the obviousness inquiry.

4. Graham factor summary

5. Claim-by-claim obviousness analysis

Claim 1 (reconstructed — full combination)

Prima facie case. Take Van Dyne (US 105,279) as the primary reference. It supplies, in combination: main reservoir (A); a top plate/collar with a shaft passing through packing (plunger G through packing g); a perforated cage/basket (perforated screw-cap D, case b) enveloping glass acid bottles; stoppers seated in the bottle mouths; a spring/elastic band (d) biasing the stopper assembly toward the bottles; and an apparatus explicitly designed to "rest on either end." The only structural element of Hughes' combination not literally in Van Dyne is the specific mounting of the vessel to the shaft via cross-bar B′, supports C, and semicircular clamps C′ engaging a groove x on the vessel — a conventional groove-and-clamp attachment, and the substitution of Hughes' single reciprocating shaft for Van Dyne's screw-plunger.

Now add Carlier & Vignon/Babcock for D1 (stopper held fixed relative to the main vessel while the acid vessel is gravity-released) and Sander (US 111,877) for the packed actuator shaft running through the top closure to open the acid discharge. A PHOSITA combining these three would have every element of claim 1.

The residual difference (D2) is the crux. Hughes' only real advance is that the machine's own weight, when it is set down inverted on protruding head b, drives the shaft and lifts the vessel off the stopper. That difference would have been obvious for three independent reasons:

1. Gravity/weight actuation was the most banal of mechanical expedients in 1873 — dead-weight prime movers appear in clocks, trip mechanisms, and countless valves and catches. Using the weight of an apparatus to trip its own release mechanism is not a new function; it is a substitution of one actuating force (machine dead weight) for another (hand, screw, lever).
2. The art already pointed to gravity and inversion for exactly this release. Carlier & Vignon used gravity (vessel tipping under its own weight) to discharge acid; Van Dyne expressly taught that the apparatus "may rest on either end." Once the machine is invertible and the actuator is a protruding shaft through the top (Sander; Van Dyne), letting the machine's weight bear on the protruding head when set down is the most direct way to make the release self-acting — a recognized desideratum, since the Babcock machine was commercially marketed as a "self-acting" engine (Cyclopaedia account).
3. The result is fully predictable. Driving a shaft by dead weight to separate a vessel mouth from a plug produces exactly the acid release Hughes describes; the CO₂ chemistry was disclaimed and known. Nothing in Van Dyne, Sander, or Carlier & Vignon teaches away from automatic, gravity-trip actuation; to the contrary, Van Dyne's "either end" language invites it.

Conclusion on claim 1: obvious under § 103 as a combination of US 105,279 + Carlier & Vignon (US 1869/reissue 1872) + US 111,877, with ordinary design choices (groove-and-clamp mounting; glass as "any suitable material"; cage "of any desired design" per Hughes' own words). A PHOSITA had a reasonable expectation of success because the mechanism is a straightforward relocation of the actuating force already used in the field.

Claim 2 (reconstructed — shaft-and-reservoir mounting sub-combination)

If claim 2 is the sub-combination of plate a with packing-box a′, shaft B (head b, groove b′), cross-bar B′, supports C, clamps C′, cage D, diaphragm D′, fixed stopper d, and spring E — each element is individually accounted for: packed shaft through top closure (Sander; Van Dyne packing g); stoppers seated in glass-vessel mouths with spring bias (Van Dyne); fixed stopper supported from the closure/cage while the vessel is released (Carlier & Vignon's cover-rod stopper); perforated cage enveloping the vessel (Van Dyne's case b + perforated cap D). The sub-combination is no more than the claim-1 combination stripped of the main reservoir — an aggregation of known parts with known functions, arranged in the only way that performs the disclosed function. Conclusion: obvious over the same references.

Claim 3 (verbatim) — "groove b′ upon shaft B . . . retaining-trigger c, and spring E"

This is a detent latch: an annular groove engaged by a pivoted trigger holds the reciprocating shaft in its retracted (filling) position; the spring biases/returns the shaft to seat the reservoir on the stopper. The individual concepts are ancient and were present in the extinguisher art:

• Holding an actuator in position: Sander's locking-staple R secures the operating handle "tightly in any position to prevent accidental displacement" — the same function as Hughes' trigger-in-groove.
• Spring bias toward the seated/closed condition: Van Dyne's elastic band/spring d presses the stopper assembly onto the bottle necks.
• Spring-loaded pivoted detents engaging annular grooves on rods are conventional latch mechanics that no PHOSITA would need a patent reference to supply.

The combination does no more than yield the predictable result of each element (positively latch the shaft open during filling; spring-return to seat). Under KSR, substituting a spring-trigger detent for a staple-lock or screw-lock is a predictable variation made with ordinary creativity. Conclusion: claim 3 is the most defensible of the three claims — because the specific three-element latch, in its disclosed functional context, has the thinnest prior-art footprint — but it is still vulnerable: no element is novel, and the combination of a detent with a return spring on a reciprocating actuator is the kind of "obvious to try"/predictable-variation finding KSR places squarely within § 103.

6. Secondary considerations and counterarguments

• Secondary considerations: none in the record (no identified litigation, no commercialization evidence, no praise/licensing). The patent expired in 1890 with no identified enforcement history.
• Possible Hughes rejoinders and responses:
  • "No reference shows weight-of-the-machine actuation." Response: substitution of an actuating force, where the same release function was already gravity-operated (Carlier & Vignon) and the machine was already invertible (Van Dyne), is not an inventive step.
  • "My stopper stays fixed; prior stoppers moved." Response: mechanically, only relative motion between plug and vessel mouth matters; Carlier & Vignon shows the vessel moving relative to a cover-held stopper, and Van Dyne shows the converse. Choice of the moving member is a designer's choice producing the identical, known result.
  • "Rapid, tool-free, automatic operation was a long-felt need." Response: no evidence of long-felt need is in the record, and the commercial "self-acting" Babcock machine shows the market already understood automatic operation before Hughes.
• Evidence cutting in Hughes' favor: the contemporaneous, rapid issuance of many competing extinguisher patents with different release mechanisms (Steiner; Latte; Dillon; Stillson & Kley) is some evidence the specific configuration space was crowded — but crowding ordinarily strengthens an obviousness case by showing multiple artisans converged on the same problem and similar solutions, and it corroborates ordinary skill in the field.

7. Bottom line

A PHOSITA in mid-1873, facing the known design problem of releasing acid into the soda solution "immediately and without tools" in an invertible soda-acid extinguisher, would have had (i) every structural element in Van Dyne, (ii) the fixed-stopper/gravity-release geometry in Carlier & Vignon/Babcock, (iii) the packed top-closure actuator in Van Dyne and Sander, and (iv) routine latch mechanics for the claim-3 detent. Combining them yields Hughes' device with a predictable result. Under Graham and KSR, and a fortiori under the contemporary Hotchkiss "invention" doctrine, claims 1–3 would likely have been held obvious — or, in 1873 terms, to lack the requisite degree of invention over the prior art.

Candor note: this conclusion rests on (a) reconstructed claims 1–2, and (b) verified content for only US 105,279 and US 111,877 plus the period-documented Carlier & Vignon/Babcock system. If the true text of claims 1–2 materially differs from the reconstruction, or if US 114,775 / US 123,783 / US 127,770 / Latte (US 142,637) prove on inspection to disclose the weight-actuated, fixed-stopper release even more directly, the obviousness case would be stronger, not weaker.