remove Time_signature_engraver only partially

[Ole Schmidt]

Hi all,

In the following snippet I want to remove the Time_signature_engraver  
only in the second and the third bar (no timesign 6/4 and 4/4 again).
How can I achive that?

thanks for a hint

ole

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

\version "2.11.36"

staffClarinet = \new Staff
{   \time 4/4
        \key bes \major
        \clef  "G_8"
        \relative c' {  
 es4 g f d      
\time 6/4
es2 d1    \bar "||:"
\time 4/4
d4 c d2 \bar ":|"
                }
}
staffTrumpet = \new Staff  {
        \key bes \major
        \clef treble
        \relative c'' {         
 bes2 c4 d ~

d8 bes c4 d1 c2 d2

        }
}
\score {
        <<
        \staffTrumpet
        \staffClarinet
        >>
        \layout  {
%%%     \context { \Staff   \remove Time_signature_engraver  }
        }
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%