diff --git a/gdata-characteristic.js b/gdata-characteristic.js
index 1a80861..dc0f9d6 100644
--- a/gdata-characteristic.js
+++ b/gdata-characteristic.js
@@ -1,8 +1,8 @@
 const bleno = require('bleno')
 const config = require('./config.json')
 const escpos = require('escpos')
-const device = escpos.Serial(config.printer.serial)
-const printer = escpos.Printer(device)
+const device = new escpos.Serial(config.printer.serial)
+const printer = new escpos.Printer(device)
 let isOpen = false
 
 device.open(()=>{
@@ -59,4 +59,8 @@ function printString(str){
   printer.cut(true, 8)
 }
 
+process.on('SIGINT', ()=>{
+	device.close()
+})
+
 module.exports = DataCharacteristic