  Submillimetre and millimetre observations are important in probing the
properties of the molecular gas and dust around obscured active galactic nuclei
(AGNs) and their feedback. With very high-resolution (0."02x0."03 (2x3 pc))
ALMA 345 GHz observations of CO 3-2, HCO$^+$ 4-3, HCN 4-3 $\nu_2$=1$f$, and
continuum we have studied the molecular outflow and nucleus of the extremely
radio-quiet lenticular galaxy NGC1377. The outflow is resolved, revealing a 150
pc long, clumpy, high-velocity, collimated molecular jet. The molecular
emission is emerging from the spine of the jet with an average diameter of 3-7
pc. A narrow-angle, rotating molecular wind surrounds the jet and is enveloped
by a larger-scale, slower CO-emitting structure. The jet and narrow wind are
turbulent ($\sigma>$40 kms$^{-1}$) and have steep radial gas excitation
gradients. The jet shows velocity reversals that we propose are caused by
precession, or episodic directional changes. We suggest that an important
process powering the outflow is magneto-centrifugal driving. In contrast, the
large-scale CO-envelope may be a slow wind, or cocoon that stems from jet-wind
interactions. An asymmetric, nuclear r$\sim$2 pc and hot (>180 K) dust
structure with a high molecular column density, N(H$_2$)$\sim1.8 \times
10^{24}$ cm$^{-2}$, is detected in continuum and vibrationally excited HCN. Its
luminosity is likely powered by a buried AGN. The mass of the supermassive
black hole (SMBH) is estimated to $\sim9\times10^6$ M$_\odot$ and the SMBH of
NGC1377 appears to be at the end of an intense phase of accretion. The nuclear
growth may be fuelled by low-angular momentum gas inflowing from gas ejected in
the molecular jet and wind. Such a feedback-loop of cyclic accretion and
outflows would be an effective process in growing the nuclear SMBH. This result
invites new questions as to SMBH growth processes in obscured, dusty galaxies.
