面对国内工程机械市场的竞争环境，各主机生产厂家都纷纷采取各种促销办法，但同时它又是最有争议、最难操作的销售形式。一经分期付款售出的产品，往往不能按合同期收回分期部分所欠余款，造成长期拖欠，影响生产厂家的资金流通。究其原因，是生产厂家没有一种有效的办法控制 Faced with the competitive environment of the domestic construction machinery market, various host manufacturers have adopted various promotion methods, but at the same time it is the most controversial and difficult to operate sales forms. Once the products are sold on an installment basis, it is not always possible to recover the balance owed by the instalments according to the contract period, causing long-term defaults and affecting the circulation of funds by the manufacturers. The reason is that manufacturers do not have an effective way to control