URDF, Attaching two joints to one link for a gripper

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HI everyone im trying to make my own gripper , but i had a problem , how can i can attach two joints to the same link? for example LINK "A" attach with link c(green color) and "A" attached with B , im used mimic tag but it dosnt work , its any one can help me please? here is my urdf code AND an image of my gripper I'm searched about "virtual links" and "dummy" but i cant find anything, well thanks for reading this post =) hope you can help me!

ROS VERSION : KINETIC

<?xml version="1.0"?>
<robot name="gripper">
    <link name="world"/>
                            <!-- BASE -->
    <link name="base_link">
        <visual>
            <geometry>
                <mesh filename="package://odam_arm/meshes/GRIPPER_DAE/base.dae" scale="1 1 1"/>
            </geometry>
        </visual>
        <material name="blue">
            <color rgba="${0/255} ${0/255} ${255/255} 1.0"/>
        </material>
        <origin rpy="0.0 0.0 0.0" xyz="0.0 0.0 0.0"/>
    </link>


    <joint name="fixed_joint" type="fixed">
        <parent link="world"/>
        <child link="base_link"/>
    </joint>

    <!-- LEFT PART BASE ACTUADOR  -->

    <link name="actBody_Link">
        <visual>
            <geometry>
                <mesh filename="package://odam_arm/meshes/GRIPPER_DAE/ActuadorBody.dae" scale="1 1 1"/>
            </geometry>
        </visual>
        <material name="blue">
            <color rgba="${0/255} ${0/255} ${255/255} 1.0"/>
        </material>
        <origin xyz=" 0 0 0.0" rpy="0.0 0.0 0.0"/>>
    </link>


    <joint name="actBody_Joint" type="revolute">
        <parent link="base_link"/>
        <child link="actBody_Link"/>
        <origin xyz=" 0.044661  -0.022722  0.016772   " rpy="0.0 0.0 0.0"/>
        <axis xyz="0 0 1 "/>
        <limit effort="200" lower="-0.02" upper="0.13" velocity="1.0"/>

    </joint>

    <!-- LEFT PART SHAFT ACTUADOR OR C PART -->
    <link name="actShaft_Link">
        <visual>
            <geometry>
                <mesh filename="package://odam_arm/meshes/GRIPPER_DAE/ActuadorShaft.dae" scale="1 1 1"/>
            </geometry>
        </visual>
        <material name="blue">
            <color rgba="${0/255} ${0/255} ${255/255} 1.0"/>
        </material>
        <origin xyz="0 0 0.0" rpy="0.0 0.0 0.0"/>>
    </link>


    <joint name="actShaft_Joint" type="fixed">
        <parent link="actBody_Link"/>
        <child link="actShaft_Link"/>
        <origin xyz="0.029065  -0.091559  0.004383   " rpy="0 0 0.3"/>
        <axis xyz="0 1 0 "/>
        <limit effort="200" lower="0.0" upper="0.05" velocity="1.0"/>
        <!-- <mimic joint="part1_Joint" multiplier="1" offset="0"/> -->
    </joint>
        <!-- PART5  OR A PART-->
    <link name="part5_Link">
        <visual>
            <geometry>
                <mesh filename="package://odam_arm/meshes/GRIPPER_DAE/parte5.dae" scale="1 1 1"/>
            </geometry>
        </visual>
        <material name="blue">
            <color rgba="${0/255} ${0/255} ${255/255} 1.0"/>
        </material>
        <origin xyz="0 0 0.0" rpy="0.0 0.0 0.0"/>>
    </link>


    <joint name="part5_Joint" type="revolute">
        <parent link="base_link"/>
        <child link="part5_Link"/>
        <origin xyz="0.043003 ...