使用tikzpicture绘制时如何在节点上将线彼此相邻放置？

Question

我想分开我的箭头，以便既可见，也将箭头从B到C命名为D

我在乳胶中的代码

\documentclass[11pt,twoside]{report}
\usepackage[american]{circuitikz}
\usepackage{pgfgantt}

\begin{document}
\tikzstyle{block} = [draw, rectangle, minimum width = 0.75cm, minimum height = 0.75cm]
\tikzstyle{sum} = [draw, circle, minimum size=.5cm, node distance=1.75cm]
\tikzstyle{input} = [coordinate]
\tikzstyle{output} = [coordinate]

\begin{tikzpicture}[node distance=2cm,auto,>=latex']
  \node [input, name=inputA] {};
  \node [input, name=inputE] {};
  \node [sum, right of=inputA] (sum) {};
  \node [block, right of=sum] (B) {$B$};

  \node [block, below of=B] (C) {$C$};
  \coordinate (inputE) at (6,-2);

  \draw [draw,->] (inputA) -- node {$A$} node[pos=0.95] {{\tiny $+$}} (sum);
  \draw [->] (sum) -- (B);
  \draw [->] (C) -| node[pos=0.99, right] {{\tiny $-$}} (sum);
  \draw [->] (inputE) -- node[above] {$D$} node[pos=0.95] {} (C);
  \draw [->, blue] (B) -|([shift={(15mm,-3mm)}]C.south east)-- ([shift={(15mm,3mm)}]C.north east)|-(C);
\end{tikzpicture}
\end{document}

给我

我怎么得到这个？

Answer 1

\documentclass{article}

\usepackage{tikz}
\usetikzlibrary{arrows}

\begin{document}

\tikzstyle{block} = [draw, rectangle, minimum width = 0.75cm, minimum height = 0.75cm]
\tikzstyle{sum} = [draw, circle, minimum size=.5cm, node distance=1.75cm]
\tikzstyle{input} = [coordinate]
\tikzstyle{output} = [coordinate]

\begin{tikzpicture}[node distance=2cm,auto,>=latex']
  \node [input, name=inputA] {};
  \node [input, name=inputE] {};
  \node [sum, right of=inputA] (sum) {};
  \node [block, right of=sum] (B) {$B$};

  \node [block, below of=B] (C) {$C$};
  \coordinate (inputE) at (6,-2);

  \draw [draw,->] (inputA) -- node {$A$} node[pos=0.95] {{\tiny $+$}} (sum);
  \draw [->] (sum) -- (B);
  \draw [->] (C) -| node[pos=0.99, right] {{\tiny $-$}} (sum);
  \draw [->] ([shift={(20mm,-5.5mm)}]C.north east) -- node[above] {$D$} node[pos=0.95] {} ([shift={(0mm,-5.5mm)}]C.north east);
  \draw [->, blue] (B) -|([shift={(15mm,10mm)}]C.north east)|-([shift={(0mm,10mm)}]C);
\end{tikzpicture}

\end{document}