Abstract:
A sprayer includes a tank having a pump for pressurizing the liquid contents of the pump. The sprayer has a hose extending from the tank for receiving liquid directly from the pump, a spray control valve and discharge nozzle for directing the spray. One or more parts from the pump inlet to the discharge nozzle are adapted to fail after a certain period of time with reuse of the sprayer.

Description:
BACKGROUND OF THE INVENTION 
     Garden and industrial sprayers are normally completely reusable and feature a pressure tank for the liquid solution to be dispensed having a sealable fill opening, an internally mounted piston/cylinder pump for pressurizing the tank interior, an outlet hose, a flow control valve associated with the hose, and an extension rod having a discharge nozzle. The tank is usually filled with the desired chemical in concentrated form and diluted by adding water to arrive at the desired solution for spraying. The chemical concentrate is purchased commercially from the desired source and may be contained in 1 gallon, 5 gallon or higher capacity bottles or containers. 
     SUMMARY OF THE INVENTION 
     A principal object of the present invention is to provide a limited time use sprayer that may be prefilled and is rendered non reusable and disposable after a certain limited period of use and/or time. 
     Another object is to provide a sprayer of the foregoing type which is sold and purchased as a complete package including a built in pump, outlet hose, spray control valve, rod extension and discharge nozzle. 
     A further object is to provide a sprayer of the foregoing type that is safe, cost effective and relatively easy to manufacture and which possesses a tank similar in appearance to the commercially available bottles or containers for chemical concentrates. 
     Still another object is to provide a sprayer of the foregoing type that requires only a single stroke of a piston cylinder pump assembly for supplying means for a spraying cycle. 
     A still further object is to provide a sprayer of the foregoing type that has the advantage of not requiring a tank capable of withstanding pressurization and consequently is intrinsically safe from overpressurization. 
     Other objects and advantages will become apparent from the following detailed description which is to be taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE FIGURES 
     FIG. 1 is a front elevational view of the sprayer of this invention as commercially sold. 
     FIG. 2 is a rear elevational view thereof. 
     FIG. 3 is a front elevational view of the sprayer ready for use. 
     FIG. 4 is an enlarged fragmentary sectional view showing the pump assembly. 
     FIG. 5 is a further enlarged longitudinal sectional view of the pump assembly. 
     FIG. 6 is a similar view showing the pump during its intake stroke. 
     FIG. 7 is a front elevational view showing another embodiment of the sprayer tank. 
    
    
     DETAILED DESCRIPTION 
     In the drawing, the sprayer package 10 as supplied to the consumer is illustrated in FIGS. 1 and 2. In this condition the tank 12 of a suitable plastic is not pressurized but contains the diluted chemical solution to be sprayed and is also suitably sealed so as to be a so called &#34;shipper&#34;. Towards this end, the pump handle 14 will be suitably releasably secured in place for example, by tape, shrink wrap or any suitable releasable clip or fastener. The pump assembly. 16 and, specifically, the top cap 18 on the pump cylinder will be suitably sealed and secured to the tank 12 across a fill opening but only after the tank 12 is filled. In this regard, the tank 12, may be formed by blow molding from a suitable resin. 
     The hose 30 and spray control valve 32 may be conveniently sealably secured to the pump handle 14 and all are placed as shown and perhaps secured in place by tape, shrink wrap or other suitable fastening means. The shrink wrap label 34 extending circumferentially around the tank 12 within the circumferential recess 35 conveniently secures the extension rod 36 and discharge nozzle 38 within the longitudinal cavity 40. Thus, the sprayer package 10 depicted in FIGS. 1 and 2 will be marketed and sold as shown with a contained chemical, preferably not under pressure, ready for spraying in the same fashion as and along with bottles of such solution or chemical concentrate. 
     Once the sprayer package 10 is purchased, the consumer prepares it for spraying by removing the fastening means holding the pump handle 14, hose 30 and control valve 32 and then freeing extension rod 36 and nozzle 38. The pump assembly 16 is then activated. 
     Referring now to pump assembly 16, it will be observed that pump cylinder 44 is suitably secured and sealed across opening 20 by the top cap 18. Cap 18 is, in turn, threadably secured and sealed across opening 20 defined by raised externally threaded neck 46 of the tank 12. Piston rod 50 having through bore 51 extends downwardly from the handle 14 and is slidable within bore 52 of the top cap 18. A preloaded spring 53 surrounds the rod 50 and is biased against the cap 18 and piston 54. The lower end of rod 50 mounts piston 54 having through bore 55 engaging the inner wall of the cylinder 44. The lower end of the cylinder 44 has secured thereto a plug 56 having openings 58 covered by the umbrella valve 60. Pulling the handle up retracts the piston against the bias of spring 53 opening valve 60 drawing liquid into the cylinder through the openings 58 from the interior of tank 12. The spring 53 will be compressed and when the handle 14 is released, valve 60 closes the opening 58, and the piston 54 is urged toward the plugged end of the cylinder to pressurize the liquid in the cylinder. Liquid will then be forced out through the bores 55 and 511 into hose 30. Since the spring 53 is preloaded, pressure is maintained until essentially all the liquid in the cylinder 44 is dispensed. 
     The valve 32 is advantageously selected for its simplicity of structure and operation. Thus, valve 32 can simply be an IV type of valve in which the hose 30 extends with the flexible arm adapted to pivot from an outer position at which the bore of the hose 30 is opened to several intermediate inner positions at which the hose is squeezed to restrict the bore opening and eventually to a fully closed position at which the bore is completely shut. 
     Accordingly, this valve 32 may include a handle 74 through which the hose 30 extends. The rod 36 may be conveniently attached to the distal end of the handle as shown. Flexible arm 76 may be depressed from a fully extended position at which the hose 30 is not pinched to a depressed position at which the hose 30 is squeezed to decrease the size of the hose bore to restrict liquid flow to a fully depressed position at which the bore is closed. Obviously other types of flow control valves may be deployed. 
     As previously explained the hose 30 also extends within and through the rod 36 and is coupled in any suitable manner with nozzle 38 selected to provide the desired discharge pattern. Where desired or necessary a cone 78 may be associated with discharge nozzle 38. 
     In order to assure the dispensing of the entire contents of the tank 12, an angled handle 80 is integrally formed on the tank 12 and is so disposed and oriented such that when the handle 80 is held, the tank 12 will tip forwardly to place the base of the cylinder 44 at the lowest most position relative to the remaining parts of the tank 12. In this regard, the angled handle 80 has a gripping part at an angle less than 90° relative to the vertical axis of the cylinder 44. 
     In order to keep the costs of the sprayer package 10 at a minimum, all parts are formed of a suitable resin. 
     The present invention also contemplates strengthening tank 12 to ensure its integrity as inexpensively as possible. In this connection, the base is formed with a reverse dome 82 to prevent ballooning and cross member 84 (see FIG. 7) is blow molded into the tank to prevent bowing of the tank sides. The bowing of the sides and ballooning of the base occur as a result of the weight of the liquid inside the tank 12. 
     It is contemplated that the sprayer of this invention has only limited use after the contents of the tank 12 has been emptied. In this regard, should the consumer attempt to remove the cap 18, the cap 18 will be destroyed, ruptured or rendered useless so that it cannot be recoupled to the threaded neck 46. The customer will then be required to purchase a refill container with the chemical solution to be sprayed which will have another cap 18. The pump cylinder will have to be removed in order to fill the tank 12 and replaced before applying the new cap 18. 
     In order to further insure only limited reuse of the sprayer 10, other options are contemplated by the present invention which can be incorporated individually or in combination. For example, spring 53 may have a limited life and will fail after a preset number of reciprocations. A filter (not shown) may be conveniently incorporated anywhere from the pump inlet to nozzle outlet which filter will become fouled with particulate matter in the chemical solution in the tank 12; or the filter material will be reactive with some element or ingredient of the solution. Another approach would be to have a plug (not shown) or any component between the pump inlet to the nozzle outlet that will dissolve over time upon contact with the chemical solution in the tank 12. A mechanical counting mechanism (not shown) can be associated with any of the components of the sprayer, that is exposed to repeated usage which will allow use and operation a specified number of times before lock-up. A piston seal or valve seal failure is also contemplated which will produce failure after some number of cycles; or the seal valve piston can erode or swell by being chemically sensitive to the chemical solution in the tank 12 so that after certain usage the part will swell, erode or fail to function. A further embodiment is to have threads fail or wear out after a number of uses such as the cap 18 or threaded neck 46. Of course, the cap 18 could fail after a certain number of uses. The spray control valve 32 could be designed to break, close or open, or otherwise fail after a certain number of activations. 
     Thus, the several aforenoted objects and advantages are most effectively obtained. Although a single somewhat preferred embodiment has been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims.