Abstract:
A manually operated sprayer for a container of liquid to be sprayed includes variable volume pump means having liquid inlet and outlet means for discharging the contents of the container. The sprayer further includes a control module having product and vent valves reciprocably disposed therein, the product and vent valves being simultaneously reciprocable by means of the manual actuator between valve open and valve closed positions. In the valve open position, the product and vent valves respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container, and in the vent closed position, the product and vent valves respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage.

Description:
BACKGROUND OF INVENTION  
       [0001]     a. Field of Invention  
         [0002]     The invention relates generally to manually actuated power sprayers for mounting to containers of liquids to be sprayed, and more particularly to a trigger operated power sprayer having improved container vent and product discharge controls during pump activation.  
         [0003]     b. Description of Related Art  
         [0004]     Manually actuated power sprayers, which are well known in the art, may include trigger sprayers adapted for manual operation in dispensing of product from a container attached thereto. During operation of the power sprayer, the container to which the manually actuated power sprayer is mounted must be vented to atmosphere to replenish the container interior with air as liquid product is dispensed. If the container is not properly and efficiently vented, the air volume or head space volume within the container which enlarges as the container is emptied of product eventually becomes sub-atmospheric thereby creating unwanted conditions of hydraulic lock and container collapse. Container venting may be carried out in a multitude of ways, utilizing both active and passive valving. While container vent control may be avoided when using, for example, a collapsible bag as the container of product is dispensed, there exist a multitude of containers and products on the market for which collapsible bags are unavailable or economically prohibitive.  
         [0005]     For improved operation of the power sprayer for which venting is required, the function of the vent as well as the product discharge controls must be coordinated such that the container is adequately vented while product is being discharged. Container vent and product discharge valving must also be controlled such that during periods of shipping and storage and other periods of non-use, the vent and product discharge ports remain sealed closed to avoid the possibility of leakage. At the same time, the vent and discharge valve controls must be efficient and economical in use during operation of a power sprayer, and must likewise be efficient and economical to fabricate and assemble into the power sprayer unit.  
         [0006]     Among conventional trigger sprayers having a container vent control is one with a flexible seal member for covering a vent hole to prevent leakage of product and to permit venting of the container during dispensing. Heretofore, conventional seal designs have been quite complex and have thus required relatively complicated manufacturing and assembly techniques. For example, conventional vent seals disclosed in U.S. Pat. No. 4,230,277, the disclosure of which is incorporated herein by reference, include non-geometric or complex geometric cross-sections, or protrusions or the like integrally molded therewith as in, for example, U.S. Pat. No. 5,603,434, the disclosure of which is also incorporated herein by reference. The fabrication and installation of such complex prior art designs can significantly increase the overall manufacturing and assembly costs of the trigger sprayer. Other effective container vent controls, as disclosed in U.S. Pat. No. 6,554,211, the disclosure of which is incorporated herein by reference, could also be improved upon in operation.  
         [0007]     There thus exists room for improvement in the number of parts, the overall costs associated with manufacturing and assembly, as well as the operation of existing manually activated sprayers, whether such sprayers are of the manual pumping type or of the battery activated type, so long as such sprayers require container vent and product discharge controls.  
         [0008]     It would therefore be of benefit to provide a manually actuated pump sprayer having in combination improved means for container venting and product discharge control operable in a repeatable and predictable manner over the life of the pump sprayer. There also remains a need for an improved means for container venting and product discharge control, which is robust in design, efficient to operate, simple to assemble and disassemble, and which is economically feasible to manufacture.  
       SUMMARY OF INVENTION  
       [0009]     The invention solves the problems and overcomes the drawbacks and deficiencies of prior art container vent and product discharge control designs for manually actuated or battery operated sprayers by providing in combination improved means for container venting and product discharge control for improved sprayer operation.  
         [0010]     The invention thus provides a manually operated sprayer for a container of liquid to be sprayed. The sprayer includes a variable volume pump means having liquid inlet means for connecting the pump means with liquid in the container, outlet means connecting the pump means with a discharge opening and a manual actuator for activating the pump means for pumping liquid from the container through the outlet means and the discharge opening. The sprayer further includes a control module having spring biased product and vent valves reciprocably disposed therein, the product and vent valves being simultaneously reciprocable by means of the manual actuator between valve open and valve closed positions. In the valve open position, the product and vent valves respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container. In the valve closed position, the product and vent valves respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage.  
         [0011]     For the sprayer described above, the product and vent valves may sealingly engage confronting internal walls in the control module to prevent flow of product and air. In a particular embodiment, the product and vent valves may each include a resilient conical section in the form of chevron seals for sealingly engaging confronting internal walls in the control module to prevent flow of product and air. The product and vent valves may be formed of a single unitary structure, or may instead be formed of a plurality of components fitted together. The product and vent valves may include a first elongated section and a second cap section fitted together. The first elongated section may include a first conical portion tapered outwardly to engage a confronting internal wall in the control module, a second elongated portion and a third elongated portion. The cap section may include a first conical portion tapered outwardly to engage another confronting internal wall in the control module, and a second elongated portion. The conical portions of the first elongated section and the second cap section may engage the confronting internal walls of the control module to prevent flow of product and air. The actuator may be depressable to first operate the pump means and thereafter activate the product and vent valves to enable flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include first and second protrusions for respectively operating a switch for engaging the motor means and thereafter operating the product and vent valves for enabling flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include a trigger lever which is normally returned to a relaxed position by a spring outwardly biasing the product and vent valves upon release of manual pressure applied to the lever. The sprayer may include electric motor means for operating the pump means, battery means for operating the motor means, and manually operable switch means for selectively operating the motor means.  
         [0012]     The invention yet further provides a manually operated sprayer for a container of liquid to be sprayed. The sprayer includes a variable volume pump means having liquid inlet means for connecting the pump means with liquid in the container, outlet means connecting the pump means with a discharge opening and a manual actuator for activating the pump means for pumping liquid from the container through the outlet means and the discharge opening. The sprayer includes a control module having spring biased product and vent flow control means disposed therein, the product and vent flow control means being operable by means of the manual actuator between valve open and closed positions. In the valve open position, the product and vent flow control means respectively prevent flow of product and air respectively into the liquid inlet means and into a vent passage in communication between atmosphere and an interior of the container. In the valve closed position, the product and vent flow control means respectively enable flow of product and air respectively into the liquid inlet means and into the vent passage.  
         [0013]     For the sprayer described above, the product and vent flow control means may sealingly engage confronting internal walls in the control module to prevent flow of product and air. In a particular embodiment, the product and vent flow control means may each include a resilient conical section sealingly engaging confronting internal walls in the control module to prevent flow of product and air. The product and vent flow control means may be formed of a single unitary structure, or may instead be formed of a plurality of components fitted together. The product and vent flow control means may include a first elongated section and a second cap section fitted together. The first elongated section may include a first conical portion tapered outwardly to engage a confronting internal wall in the control module, a second elongated portion and a third elongated portion. The cap section may include a first conical portion tapered outwardly to engage another confronting internal wall in the control module, and a second elongated portion. The conical portions of the first elongated section and the second cap section may engage the confronting internal walls of the control module to prevent flow of product and air. The actuator may be depressable to first operate the pump means and thereafter activate the product and vent flow control means to enable flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include first and second protrusions for respectively operating a switch for engaging the motor means and thereafter operating the product and vent flow control means for enabling flow of product and air into the liquid inlet means and the vent outlet passage, respectively. The manual actuator may include a trigger lever which is normally returned to a relaxed position by a spring outwardly biasing the product and vent flow control means upon release of manual pressure applied to the lever. The sprayer may include electric motor means for operating the pump means, battery means for operating the motor means, and manually operable switch means for selectively operating the motor means.  
         [0014]     Additional features, advantages, and embodiments of the invention may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Moreover, it is to be understood that both the foregoing summary of the invention and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the invention as claimed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate preferred embodiments of the invention and together with the detail description serve to explain the principles of the invention. In the drawings:  
         [0016]      FIG. 1  is a side elevation view of the power sprayer, partly broken away, according to the present invention;  
         [0017]      FIG. 2  is a cross-sectional view of the power sprayer of  FIG. 1 , taken substantially along line  2 - 2  in  FIG. 1 , illustrating the contact arrangement for operating the power sprayer;  
         [0018]      FIG. 3  is an exploded view of the discharge/vent control module of the power sprayer of  FIG. 1 ;  
         [0019]      FIG. 4  is an illustrative cross-sectional view of the discharge/vent control module of  FIG. 3 , taken substantially along line  4 , 5 - 4 , 5  in  FIG. 3 , illustrating a product valve and an identical vent valve in a closed position; and  
         [0020]      FIG. 5  is similar to  FIG. 4  showing the product valve and the identical vent valve in an open position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0021]     Referring now to the drawings wherein like reference numerals designate corresponding parts throughout the several views,  FIGS. 1-5  illustrate a battery operated power sprayer according to the present invention, generally designated power sprayer  10 .  
         [0022]     Before proceeding with the detailed description of power sprayer  10 , those skilled in the art will appreciate in view of this disclosure that the components and features of sprayer  10  discussed herein may be applicable for use with a manual pumping type sprayer (not shown) or for use with the battery activated type sprayer as shown in  FIG. 1 .  
         [0023]     Referring to  FIG. 1 , power sprayer  10  of the present invention is shown as having coupled thereto a container closure  12  for mounting the sprayer to a container  14  of liquid product to be sprayed. Power sprayer  10  may generally include housing  16  made of a suitable plastic material, for example, and having enclosed therein pump system  18 , container vent and product discharge control module  20  (hereinafter “control module  20 ”) and power unit  22 .  
         [0024]     As shown in  FIG. 1 , power sprayer  10  may have hingedly mounted thereto as at  24  an actuator which may comprise a trigger lever  26  for actuating sprayer  10 . Housing  16  may include a discharge nozzle cap  28  affixed thereon and including a discharge orifice (not shown) formed therein at the terminal end of discharge tube  30  of the sprayer. Discharge tube  30  may be operatively connected to pump  32  of pump system  18  for discharging product from container  14  under pressure as needed. Pump  32  may include a variable volume pump chamber (not shown) into which an inlet passage extends. Product outlet tube  34  may be operatively connected at one end thereof to the inlet passage of pump  32 , and to product side  36  of control module  20  at the other end thereof. A vent inlet tube  38  may include one end thereof operatively connected to vent side  40  of control module  20 , and the other end thereof connected to an opening  41  adjacent the discharge orifice of discharge nozzle cap  28  for venting container  14  during use. Pump  32  may be operated by an electric motor (not shown) disposed behind pump  32  via gearing and cams in a manner similar to that disclosed in U.S. Pat. No. 5,716,007, the disclosure of which is incorporated herein by reference. A pair of batteries (not shown) may be housed within suitable compartments of the sprayer in power unit  22 , and may be insertable from the rear end of sprayer  10 . A battery cover  42  may be used to cover the batteries and may be snap-fitted in place onto power sprayer  10 , as shown in the closed configuration of  FIG. 1 .  
         [0025]     Referring to  FIG. 2 , a metal spring leg  44  may be mounted to the sprayer such that when depressed by means of arms  46  of trigger lever  26 , a depressable on/off switch  48  energizes control mechanism  47  for allowing current to flow to the motor for pump system  18  for operating pump  32 . Upon the release of trigger lever  26 , outwardly biased spring leg  44  releases switch  48  to its off position so as to shut off the motor for pump system  18  and thereby prevent product from being discharged out through the orifice of discharge nozzle cap  28 . It would be apparent to those skilled in the art in view of this disclosure that instead of depressable on/off switch  48 , other arrangements, such as a metal contact spring leg  44  directly contacting a battery metal contact to close an electrical circuit upon being depressed by means of arms  46  of trigger lever  26 , could be utilized for allowing current to flow to the motor for pump system  18  for operating pump  32 .  
         [0026]     As shown in  FIGS. 1 and 2 , in addition to arms  46 , trigger lever  26  may include projections  50  in contact with product and vent valves  52 ,  54  for controlling the operation thereof. In the embodiment shown, arms  46  and projections  50  may be configured such that by manually depressing trigger lever  26 , arms  46  initially press spring leg  44  to engage switch  48 , and thereafter, projections  50  simultaneously engage product and vent valves  52 ,  54  to press valves  52 ,  54  to allow product and air to pass via valves  52 ,  54  after a slight delay.  
         [0027]     Referring to  FIGS. 1 and 3 - 5 , the configuration and operation of control module  20  will next be described in detail.  
         [0028]     Specifically, as shown in  FIG. 3 , product and vent valves  52 ,  54 , respectively, of control module  20  may be respectively housed in product and vent housings  56 ,  58 , and biased outwardly by means of springs  60 . Product and vent valves  52 ,  54  may be formed of a two-piece structure including caps  62  assembled onto elongated valve sections  64 ,  66  for ease of manufacture, but may be manufactured of a one piece structure as would be apparent to those skilled in the art.  
         [0029]     Referring next to  FIGS. 4 and 5 , which respectively illustrate cross-sectional views of the module of  FIG. 3 , taken along lines  4 - 4  and  5 - 5  in  FIG. 3 , product valve  52  is illustrated in closed and opened positions respectively. It is to be understood that the layout and operation of vent valve  54  and vent housing  58  are identical to that of product valve  52  and product housing  56 . Accordingly, the description hereinafter of product valve  52  and product housing  56  will likewise apply identically to vent valve  54  and vent housing  58 .  
         [0030]     Specifically, as shown in  FIGS. 3 and 4 , product and vent valves  52 ,  54 , may each include fixedly connected first and second sections designated as elongated valve section  64  and cap  62 . Elongated valve section  64  may include a first conical portion  68 , a second elongated portion  70 , and a third elongated portion  72  having a reduced diameter cross-section as compared to portion  70 . Elongated portions  70 ,  72  may be formed of a uniform cross-section along the central longitudinal axis of valve  52 . Elongated portion  72  may be dimensioned to fit within the cavity in cap  62 , as shown in  FIG. 4 . Cap  62  may include a conical portion  74  and an elongated portion  76  formed of a uniform cross-section along the central longitudinal axis of cap  62 . For assembly, elongated valve section  64  and cap  62  may be fitted together as shown in  FIG. 4  and retained in the configuration of  FIG. 4  by means of friction or other such means known in the art. Conical portions  68  and  74  of elongated valve section  64  and cap  62 , respectively, may include a tapered internal configuration to define resilient seal members  78 ,  80  as shown in  FIG. 4 . When fitted within product housing  56 , resilient seal members  78 ,  80  sealingly engage the confronting walls of housing  56  to form a seal. Likewise, when fitted within vent housing  58 , resilient seal members  78 ,  80  sealingly engage the confronting walls of housing  58  to form a seal.  
         [0031]     Referring to  FIG. 4 , product housing  56  may generally include outlet end  82  having product outlet tube  34  connected thereon and inlet end  84  having product inlet tube  86  connected thereon. Product inlet tube  86  may be connected to a dip tube  88  disposed in container  14  through container closure  12 . Likewise, vent housing  58  may generally include outlet end  85  having vent outlet tube  100  connected thereon and inlet end  98  having vent inlet tube  38  connected thereon. In the particular embodiment shown, housing  56  may include first through fourth cross sectional areas  90 ,  92 ,  94  and  96 , respectively. Areas  90  and  94  may include a generally uniform cross-section along the central longitudinal axis of housing  56 , whereas areas  92  and  96  may be tapered inwardly and outwardly, respectively, as shown in  FIGS. 4 and 5 . It would be apparent to those skilled in the art that the specific cross-sectional configurations shown for housings  56  and  58  are for illustrative purposes only, and are not intended to limit the scope of the present invention to the specific embodiment shown.  
         [0032]     Once fitted within housing  56 , as shown in  FIG. 4 , resilient members  78 ,  80  of product valve  52  may be respectively disposed in engagement with areas  94  and  90  of housing  56  for sealing product valve  52  in a closed, at-rest position. Likewise, once fitted within housing  58 , as shown in  FIG. 4 , resilient members  78 ,  80  of vent valve  54  may be respectively disposed in engagement with areas  94  and  90  of housing  58  for sealing vent valve  54  in a closed, at-rest position. When trigger lever  26  is pressed to operate pump system  18  by means of the engagement of spring leg  44  and switch  48 , as briefly discussed above and as shown in  FIG. 5 , protrusions  50  of trigger lever  26  simultaneously move product and vent valves  52 ,  54  inwards within housings  56 ,  58 , respectively. In the  FIG. 5  position of product valve  52 , the inlet to the pump is valved open such that product within container  14  may be suctioned in through inlet end  84  in the direction of arrow-P 1 , around the outer circumference of portions  68  and  70  of valve  52 , and out through outlet end  82  in the direction of arrow-P 2  to then be fed into product outlet tube  34 , and out through discharge tube  30  via pump  32 . Likewise, in the  FIG. 5  position of vent valve  54 , the air vent is opened such that air may be suctioned in through opening  41  ( FIG. 1 ) and then through inlet end  98  in the direction of arrow-A 1 , around the outer circumference of portions  68  and  70  of valve  54 , and out through outlet end  85  in the direction of arrow-A 2  to then be fed into vent outlet tube  100  into container  14 . Upon the release of trigger lever  26 , product and vent valves  52 ,  54  return to their rest position shown in  FIG. 4  under the bias of spring  60 .  
         [0033]     As discussed above, various modifications may be made to power sprayer  10  without departing from the scope of the present invention. For example, seal rings or other such means may be used instead of resilient members  78  and  80  on valves  52 ,  54  for sealing the respective inlet and outlet ends of the valves from air or product as needed. Moreover, instead of the axially reciprocable vent valves  52 ,  54  illustrated, flap valves may be provided within control module  20  and be operable by trigger lever  26  to control flow of air and product as needed.  
         [0034]     Although particular embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those particular embodiments, and that various changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined in the appended claims.