Preparation delivery assembly and device having multiple needles

A preparation delivery device, comprising a preparation delivery assembly, and a storage portion for storing a preparation, the storage portion is in communication with the preparation delivery assembly to supply the preparation to the preparation delivery assembly,

• wherein the preparation delivery assembly comprises:
• a first substrate, a second substrate, and at least two needles of different lengths, each of the needles is a hollow needle having a hollow structure;
• wherein two side walls are provided between the first substrate and the second substrate to define a first chamber for containing a preparation by the first substrate, the second substrate, and the two side walls;
• at least one first channel that is in communication with the first chamber is provided in the second substrate in a direction substantially perpendicular to the second substrate;
• and
• the needles are arranged on a surface of the second substrate distal to the first substrate, and each of the needles is in communication with the first chamber through the at least one first channel to deliver the preparation,
• wherein a third channel is provided in the first substrate in a direction substantially perpendicular to the first substrate, and one end of the third channel is in communication with the first chamber so as to guide the preparation introduced from the other end of the third channel into the first chamber;
• wherein at least one of the first and second substrates is made of a flexible material;
• wherein at least one recess is provided on a surface of the first substrate proximal to the second substrate, and an elastic isolation membrane is provided between the recess and the first chamber to define a second chamber by the recess and the elastic isolation membrane;
• and
• a second channel is further provided in the first substrate in a direction substantially parallel to the first substrate, and one end of the second channel is in communication with the second chamber, and the other end of the second channel is in communication with outside so as to introduce air from the outside into the second chamber;
• wherein when external pressure is applied to the assembly, a valve at the other end of the second channel is opened to introduce air into the second chamber, and the air in the second chamber pushes up the elastic isolation membrane, so that the preparation flows towards the first channel.