nil is getting saved for an image in carrierwave - ruby-on-rails

Question

A product can have multiple images. But each image should be uploaded one at a time.
Here is the schema for the product
create_table "products", force: :cascade do |t|
t.json "images"
end
Here is the carrierwave mounting
class Product < ActiveRecord::Base
mount_uploader :images, ProductUploader
end
Here is the carrierwave generator
class ProductUploader < CarrierWave::Uploader::Base
# Include RMagick or MiniMagick support:
# include CarrierWave::RMagick
# include CarrierWave::MiniMagick
# Choose what kind of storage to use for this uploader:
storage :file
# storage :fog
# Override the directory where uploaded files will be stored.
# This is a sensible default for uploaders that are meant to be mounted:
def store_dir
"uploads/#{model.class.to_s.underscore}/#{mounted_as}/#{model.id}"
end
# Provide a default URL as a default if there hasn't been a file uploaded:
# def default_url
# # For Rails 3.1+ asset pipeline compatibility:
# # ActionController::Base.helpers.asset_path("fallback/" + [version_name, "default.png"].compact.join('_'))
#
# "/images/fallback/" + [version_name, "default.png"].compact.join('_')
# end
# Process files as they are uploaded:
# process scale: [200, 300]
#
# def scale(width, height)
# # do something
# end
# Create different versions of your uploaded files:
# version :thumb do
# process resize_to_fit: [50, 50]
# end
# Add a white list of extensions which are allowed to be uploaded.
# For images you might use something like this:
# def extension_whitelist
# %w(jpg jpeg gif png)
# end
# Override the filename of the uploaded files:
# Avoid using model.id or version_name here, see uploader/store.rb for details.
# def filename
# "something.jpg" if original_filename
# end
end
Here is the view
<%= simple_form_for #product, method: :post, url: save_image_path do |f| %>
<%= f.file_field :avatar_1 %>
<%= f.submit :submit %>
<% end %>
Here is the controller
class UploadController < ApplicationController
def show
#product = Product.find(1)
end
def create
byebug
#product = Product.find(1)
#product.images = params[:product][:avatar_1]
#product.save
end
end
But the nil is getting updated in the images of product, instead of image. Can someone please help me with this.