Slide stainer with controlled fluid flow

Abstract

An automated slide stainer with fluid flow control. The fluid flow control controls the flow rate of fluid, e.g., water, applied to at least one slide by the slide stainer. In an automated slide stainer that applies reagents to slides to stain biological specimens on the slides, the flow rate controlled fluid can be used to adequately rinse the slides without damaging the biological specimens contained on the slides.

What is claimed is  
     
         1 . A slide stainer with fluid flow control, said slide stainer for staining and rinsing at least one slide, said slide stainer comprising: 
 a plurality of cavities, a first one of said cavities for applying a first fluid to the at least one slide and a second one of said cavities for rinsing the at least one slide with a second fluid;    a transport for transporting the at least one slide between said first and second cavities; and    a flow control system for controlling the flow rate of said second fluid to said second cavity.    
     
     
         2 . The slide stainer of  claim 1 , wherein the flow control system maintains the flow rate at a set rate.  
     
     
         3 . The slide stainer of  claim 2 , wherein the set rate is set by an operator.  
     
     
         4 . The slide stainer of  claim 1 , wherein said flow control system is a closed-loop flow control system.  
     
     
         5 . The slide stainer of  claim 1 , wherein said flow control system comprises at least: 
 a controlled flow device having an input port for receiving said second fluid from a fluid supply line, an output port for passing said second fluid, and a control terminal for receiving a flow control signal, said controlled flow device controlling the flow rate of said second fluid based on the flow control signal received at the control terminal;    a sensor coupled to said controlled flow device for sensing the flow rate through said controlled flow device, said sensor having a flow rate terminal producing a flow rate signal indicative of the sensed flow rate; and    a controller having a sensor terminal coupled to the flow rate terminal of said sensor and a control terminal coupled to the control terminal of said controlled flow device, said controller producing the flow control signal for controlling said controlled flow device based on the flow rate signal to regulate the flow rate of said second fluid.    
     
     
         6 . The slide stainer of  claim 5 , further comprising: 
 a pressure regulator coupled between the fluid supply line and said controlled flow device, said pressure regulator having an input port coupled to the fluid supply line for receiving the second fluid and an output port coupled to the input port of said controlled flow device, said pressure regulator limiting pressure at the output port of said pressure regulator.    
     
     
         7 . The slide stainer of  claim 6 , further comprising: 
 a reservoir for receiving excess fluid from said second one of said cavities and supplying said excess fluid to the fluid supply line.    
     
     
         8 . A flow rate control system for use in a slide stainer, said slide stainer receiving fluid from a fluid supply line, said flow rate control system comprising: 
 a controlled flow device having an input port for receiving the fluid from the fluid supply line, an output port for passing the fluid, and a control terminal for receiving a flow control signal, said controlled flow device controlling the flow rate of the fluid based on the flow control signal received at the control terminal, said controlled flow rate fluid being applied to at least one slide;    a sensor coupled to said controlled flow device for sensing the flow rate through said controlled flow device, said sensor having a flow rate terminal producing a flow rate signal indicative of the sensed flow rate; and    a controller having a sensor terminal coupled to the flow rate terminal of said sensor and a control terminal coupled to the control terminal of said controlled flow device, said controller producing the flow control signal for controlling said controlled flow device based on the flow rate signal to regulate the flow rate.    
     
     
         9 . The system of  claim 8 , wherein the flow control system maintains the flow rate at a set rate.  
     
     
         10 . The system of  claim 8 , further comprising: 
 a pressure regulator coupled between the fluid supply line and said controlled flow device, said pressure regulator having an input port coupled to the fluid supply line for receiving the fluid and an output port coupled to the input port of said controlled flow device, said pressure regulator limiting fluid pressure at the output port of said pressure regulator.    
     
     
         11 . The system of  claim 10 , the fluid in the fluid supply line being supplied from a reservoir.  
     
     
         12 . The system of  claim 8 , wherein said controller is selected from a group consisting of state machines, processors, microprocessors, microcontrollers, logic gates, digital signal processors, and analog circuits.  
     
     
         13 . A method for applying fluid to at least one slide comprising the steps of: 
 applying a first fluid to the at least one slide; and    controlling the flow rate of said first fluid, wherein the flow rate is maintained at a set rate.    
     
     
         14 . The method of  claim 13 , further comprising the step of: 
 applying a second fluid to the at least one slide prior to applying said first fluid, wherein said step of applying said first fluid removes at least a portion of said first fluid.    
     
     
         15 . The method of  claim 13 , wherein said step of applying said first fluid comprises at least the steps of: 
 supplying said first fluid to a vessel at the controlled flow rate; and    dipping the at least one slide into said vessel.    
     
     
         16 . The method of  claim 15 , further comprising at least the step of: 
 agitating the at least one slide within said vessel.    
     
     
         17 . The method of  claim 13 , wherein said controlling step comprises at least the steps of: 
 sensing the flow rate of said first fluid; and    controlling the flow rate based on said sensed flow rate.    
     
     
         18 . The method of  claim 17 , wherein said controlling step further comprises at least the step of: 
 regulating the pressure of said first fluid.    
     
     
         19 . A method for rinsing at least one slide in a slide stainer comprising the steps of: 
 controlling the flow rate of a rinse fluid from a rinse fluid supply line; and    applying said rinse fluid to the at least one slide.    
     
     
         20 . The method of  claim 19 , wherein said controlling step comprises at least the step of: 
 maintaining the flow rate at a set rate.    
     
     
         21 . The method of  claim 19 , wherein said controlling step comprises at least the steps of: 
 sensing the flow rate of said rinse fluid; and    controlling the flow rate based on said sensed flow rate.    
     
     
         22 . The method of  claim 21 , wherein said controlling step further comprises at least the step of: 
 regulating the pressure of said rinse fluid from said rinse fluid supply line.    
     
     
         23 . A slide stainer for staining at least one slide comprising: 
 means for staining the at least one slide with at least one stain; and    means for applying a fluid to the at least one slide at a controlled flow rate to remove at least a portion of said at least one stain.    
     
     
         24 . The method of  claim 23 , wherein said applying means comprises at least: 
 means for maintaining said controlled flow rate at a set rate.    
     
     
         25 . The slide stainer of  claim 23 , wherein said applying means comprises at least: 
 means for receiving said fluid;    means for controlling said flow rate of said fluid; and    means for applying said fluid having said controlled rate to the at least one slide.    
     
     
         26 . The slide stainer of  claim 25 , said controlling means comprises at least: 
 means for sensing said flow rate of said fluid; and    means for controlling said flow rate based on said sensed flow rate.    
     
     
         27 . A method for supplying a fluid to at least one specimen comprising the steps of: 
 applying a fluid to at least one specimen; and    controlling the flow rate of the fluid.    
     
     
         28 . The method of  claim 27 , wherein said controlling step comprises at least the step of: 
 maintaining the flow rate at a set rate.