Ruby on Rails

i have such model:

    class ToType < ActiveRecord::Base

      attr_accessible :Name, :TYP_CCM, :TYP_CCM_TAX, :TYP_CDS_ID, :TYP_CTM, :TYP_CYLINDERS, :TYP_DOORS, :TYP_HP_FROM, :TYP_HP_UPTO, :TYP_ID, :TYP_KV_ABS_DES_ID, :TYP_KV_ASR_DES_ID, :TYP_KV_AXLE_DES_ID, :TYP_KV_BODY_DES_ID, :TYP_KV_BRAKE_SYST_DES_ID, :TYP_KV_BRAKE_TYPE_DES_ID, :TYP_KV_CATALYST_DES_ID, :TYP_KV_DRIVE_DES_ID, :TYP_KV_ENGINE_DES_ID, :TYP_KV_FUEL_DES_ID, :TYP_KV_FUEL_SUPPLY_DES_ID, :TYP_KV_MODEL_DES_ID, :TYP_KV_STEERING_DES_ID, :TYP_KV_STEERING_SIDE_DES_ID, :TYP_KV_TRANS_DES_ID, :TYP_KV_VOLTAGE_DES_ID, :TYP_KW_FROM, :TYP_KW_UPTO, :TYP_LA_CTM, :TYP_LITRES, :TYP_MAX_WEIGHT, :TYP_MMT_CDS_ID, :TYP_MOD_ID, :TYP_PCON_END, :TYP_PCON_START, :TYP_RT_EXISTS, :TYP_SORT, :TYP_TANK, :TYP_VALVES, :is_in_to

      set_primary_key :TYP_ID

      belongs_to :to_model

      has_many :to_articles, :foreign_key => "to_type_id", :dependent => :destroy

    end

    

    class ToArticle < ActiveRecord::Base

      attr_accessible :details, :manufacturer, :name, :oem_number, :only_with_vin, :quantity, :to_type_id

      belongs_to :to_type, :foreign_key => "TYP_ID"

      belongs_to :to_engine

    end

(some db is converted from big catalog, so rails conventions are a little bit missed)

my show view of to_type is:

part of it:

 

    %td

                = link_to "Подробнее", admin_catalog_to_to_article_path(c), :class=>'btn btn-primary'

                = link_to "Редактирование", edit_admin_catalog_to_to_type_path(c), :class=>'btn btn-warning'

                = link_to "Удалить", admin_catalog_to_to_type_path(c), :confirm => "!!!Тип #{c.Name} будет удалён!!!! Вы уверены?", :method => :delete, :class => "btn btn-danger"

my show action work normally, also controller:

    class Admin::Catalog::To::ToTypesController < ApplicationController

      respond_to :html

    

      before_filter :auth_user

    

      def auth_user

        redirect_to new_admin_session_path unless admin_signed_in?

      end

    

      def show

        @mod_id = params[:id]

        @man = ToType.find(:all, conditions: {:TYP_MOD_ID => @mod_id}, order: "Name ASC")

        render :layout => 'admin'

      end

    

      def edit

        @man = ToType.find(params[:id])

        render :layout => 'admin'

      end

    

      def update

        @man = ToType.find(params[:id])

        if @man.update_attributes(params[:to_type])

          redirect_to admin_catalog_to_to_type_path(@man.TYP_MOD_ID)

        else

          render :layout => 'admin'

        end

      end

    

      def new

        @man = ToType.new

        @mod_id = params[:mod_id]

        render :layout => 'admin'

      end

    

      def create

        @man = ToType.new(params[:to_type])

        @mod_id = params[:mod_id]

        @man.TYP_MOD_ID = @mod_id

        if @man.save

          redirect_to admin_catalog_to_to_type_path(@mod_id)

        else

          render :layout => 'admin'

        end

      end

    

      def destroy

        @man = ToType.find(params[:id])

        if @man.destroy

          redirect_to admin_catalog_to_to_type_path(@man.TYP_MOD_ID)

        else

          render :layout => 'admin'

        end

      end

    end

    and route:

    

    namespace :admin do

      namespace :catalog do

          namespace :to do

            resources :to_manufacturers, 

                      :to_models, 

                      :to_types, 

                      :to_articles

          end

        end

    

      end

form partial:

    = form_for [:admin, :catalog, :to, @typ] do |f|

      = f.label :id

    ...

when i try edit or create i get:

    undefined method `model_name' for NilClass:Class

i think that something is bad with connection with model: with update and create. In log i see that object is founded in db for edit for example, and in log i can see that @man is not empty, but i still get undefined method `model_name' for NilClass:Class . Why?