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E21D 23/0454

Trailing plates

Official title: {Trailing plates; Coal face or goaf side sprags (specially adapted for the placing of filling-up materials E21D23/0481)}

E21D23/0454 (Trailing plates) appears on 14 US grants and 2 published applications in this corpus.

Search patents in E21D

Granted patents: 14
Published applications: 2
Assignees: 14
Inventors: 33
Latest grant: 19 Feb 2019

Filings by year

E21D 23/0454: granted patents and published applications per publication year
Year	Granted patents	Published applications
1976	1	0
1977	0	0
1978	1	0
1979	0	0
1980	2	0
1981	0	0
1982	1	0
1983	2	0
1984	1	0
1985	3	0
1986	0	0
1987	0	0
1988	1	0
1989	0	0
1990	0	0
1991	0	0
1992	0	0
1993	0	0
1994	0	0
1995	0	0
1996	0	0
1997	0	0
1998	0	0
1999	0	0
2000	0	0
2001	0	0
2002	0	0
2003	0	0
2004	0	0
2005	0	0
2006	0	0
2007	0	0
2008	0	0
2009	0	0
2010	0	0
2011	0	0
2012	0	0
2013	0	1
2014	0	0
2015	1	0
2016	0	0
2017	0	1
2018	0	0
2019	1	0

By publication year. Applications have been published since 2001.

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