Patent US3791090A successfully refreshed from Google Patents.
US3791090A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Building block
Assignee: Individual
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Filing: 1971-12-30
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Granted: 1974-02-12
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Expires: 1991-12-30
Abstract
Abstract A building block having dovetail tongue and groove configuration for interlocking with adjacent blocks by sliding in a longitudinal direction. The dovetail tongue protrudes outwardly from one side of the block and has two widened longitudinal end portions have a cross-sectional shape defining an inverted triangular wedge which end portions are interconnected by an intermediate portion rectangular in cross section which intermediate portion extends one-third the length of the tongue. The opposite side surface of the block has a complementary shape inverse to that of the tongue forming a groove of constant depth. The end portions of the groove are of slotted dovetail configuration widening from the opposite side surface inwardly of the block. The ends of the recess have substantially the width of the intermediate portion of the tongue whereby the tongues may be longitudinally slid into the recess for interlocking engagement.
Inventors
- 👤 A Kniefel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:26
CPC Classifications
E; E04; E04B; E04B2/00; E04B2/02; E04B2/04; E04B2/06; E04B2/08; E04B2002/0202; E04B2002/0232; E04B2002/0234; E04B2002/0243; E04B2002/0252
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
247 words
An elongated generally rectangular building block for stacking with other like blocks, said building block having a longitudinally disposed tongue protruding outwardly a substantially constant amount from one side surface of said block, said tongue including two widened longitudinal end portions, each end portion having a cross-sectional shape substantially defining an inverted triangular wedge, said end portions being interconnected by a relatively narrow intermediate portion of substantially rectangular cross-sectional shape, each of said two end portions and said intermediate portion extending approximately one-third the length of said tongue, the opposite side surface of said building block incorporating a longitudinal groove having a shape complementary and inverse to that of said tongue, said groove having a substantially constant depth from said opposite side surface and including a central substantially rectangular recess and two end recesses disposed to either side of said central recess and merging therewith, each end recess of said groove being of slotted dovetail shape widening from said opposite side surface inwardly with the width of each end recess at said opposite surface being substantially equal to the width of said intermediate portion of said tongue, said central recess of said groove being such as to receive either end portion of the tongue of another like block, said block thereafter being adapted to be slid longitudinally of one another whereby the end portion of said another like block are received and accommodated in said end recesses of said groove such that said blocks are interlocked together.
Claim 2
Dependent Claim
247 words
An elongated generally rectangular building block for stacking with other like blocks, said building block having a longitudinally disposed tongue protruding outwardly a substantially constant amount from one side surface of said block, said tongue including two widened longitudinal end portions, each end portion having a cross-sectional shape substantially defining an inverted triangular wedge, said end portions being interconnected by a relatively narrow intermediate portion of substantially rectangular cross-sectional shape, each of said two end portions and said intermediate portion extending approximately one-third the length of said tongue, the opposite side surface of said building block incorporating a longitudinal groove having a shape complementary and inverse to that of said tongue, said groove having a substantially constant depth from said opposite side surface and including a central substantially rectangular recess and two end recesses disposed to either side of said central recess and merging therewith, each end recess of said groove being of slotted dovetail shape widening from said opposite side surface inwardly with the width of each end recess at said opposite surface being substantially equal to the width of said intermediate portion of said tongue, said central recess of said groove being such as to receive either end portion of the tongue of another like block, said block thereafter being adapted to be slid longitudinally of one another whereby the end portion of said another like block are received and accommodated in said end recesses of said groove such that said blocks are interlocked together.
Claim 3
Dependent Claim
42 words
A building block as defined in claim 1, further including a dovetail recess disposed in at least one end surface of said block adapted to receive a locking device of complementary shape whereby two blocks can be locked together end to end.
Claim 4
Dependent Claim
43 words
A building block as defined in claim 2, further including a dovetail recess disposed in one side surface of the block adapted to receive a locking device of complementary shape whereby two blocks can be locked together at right angles to one another.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |