1924
Founded
1938
Launch as Tohatsu Springs Co.,Ltd.
1952
Introduced manufacturing facilities for bed springs
1954
Released the standardized under-floor spring for martial art dojos
1958
Released the standardized stranded wire springs
1966
Released the S,M and L Tohatsu JIS standard springs (initial models)
1968
Established both the head office and factory in Tokyo Ota ward.
1974
Partcipated in JIS standardization of press die coil springs
1975
Introduced a large coiling machine from West Germany (currently Germany)
1976
Changed the standards for TF,TL,TM,TH,and TB Tohatsu JIS standard springs
JIS standard (JIS B 5012) established based on the Tohatsu JIS standard
1977
No.2 factory established in Tokyo Ota ward
1978
Released the standardized LR and MR round coil springs
1982
Released the standardized TR Tohatsu springs used with high deflection
1983
Factories and head office moved to current location
Released the standardized JA and JB J Springs
1986
Head office established in Tokyo Ota ward
1988
Materials warehouse established in Shizuoka prefecture
Released the standardized S·w·i·f·t (automobile suspension springs)
1990
Released the standardized TY Tohatsu springs used with high deflection
1993
Introduced automatic electro-deposition apparatus for springs
1998
Introduced a unit-type automatic warehousing system
Released the standardized S·w·i·f·t (automobile suspension springs)
2000
Released the SPORT MACH (automobile suspension springs)
2001
Acquired ISO9001
2005
Released the standardized ISO STANDARD (spring conforming to international standards)
2007
Released the standardized Tohatsu α springs
2008
Released the standardized RG resin guide
2009
Released the standardized TU Tohatsu springs used with high deflection
Establishd the Zhejiang Dongfa Springs Co.,Ltd (a manufacturing company) in Zhejiang Province, China
