Switch for pedestal sump pump

Information

  • Patent Grant
  • 6461114
  • Patent Number
    6,461,114
  • Date Filed
    Tuesday, August 8, 2000
    24 years ago
  • Date Issued
    Tuesday, October 8, 2002
    22 years ago
Abstract
A pedestal sump pump includes a motor with a housing and a water-level-response system attached to the motor. The water-level-response system includes a connecting rod with upper and lower limit stops, a float, and a switch assembly mounted partially within the motor housing. The assembly includes a switch housing and a lever pivotably mounted to the switch housing such that the lever can be toggled between on and off positions. The lever includes an aperture in the first end of the lever and a cam surface on the second end of the lever. The assembly also includes a retainer clip removably attached to the housing to retaining the lever in place, the clip including a spring tab to force the lever into one of the on and off positions, and a microswitch removably mounted in the switch housing.
Description




FIELD OF THE INVENTION




The invention relates to pedestal sump pumps and to switches for controlling the operation of such pumps.




BACKGROUND OF THE INVENTION




Pedestal sump pumps require a switch that can cause the pump to be switched on and off based on the functioning of a float mechanism reacting to the water level in a sump. Because of the special functionality necessary in these switches, the switches in prior art pumps are typically complicated. In most cases, these switches need to mounted adjacent or on top of the motor housing due to their size. Prior art sump pump switches are also typically bulky and expensive to build and maintain. Mounting such a switch outside of the motor housing exposes the switch to potential damage.




SUMMARY OF THE INVENTION




The invention provides an improved switch assembly that solves these problems through a simple design and a small size that allow the switch assembly to be mounted within a motor housing. The switch assembly is snapped together without fasteners, and is mounted within the motor housing with only one fastener. The switch assembly can employ a variety of widely-available and inexpensive microswitches. Except for the microswitch, the assembly is preferably made of three injection-molded parts and is therefore inexpensive to manufacture. The actuating lever of the switch assembly is constructed to be able to tolerate the abuse of shipping and handling.




More specifically, the invention provides a sump pump including a motor and a water-level-response system attached to the motor. The water-level-response system includes a float rod or connecting rod having thereon a float. The switch assembly is mounted inside the motor housing and includes a switch housing, a lever and a retainer, all of which are preferably injection-molded out of plastic. The switch housing is mounted inside the motor housing with a single fastener, preferably a screw. The assembly also includes a microswitch. The microswitch snaps into the switch housing from below, the lever is pivotably mounted on top of the switch housing, and the retainer snaps onto the switch housing over the lever to hold the lever on the housing. The lever engages the microswitch and can be toggled between on and off positions corresponding to the on and off or closed and open states of the microswitch. The lever extends from the motor housing and is operably connected to the float rod so that movement of the float rod opens and closes the microswitch. The retainer has a spring tab engaging a cam surface on the end of the lever so as to cause the lever to snap into the on and off positions.




Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1

is an elevation view, partially in section, of a pedestal sump pump embodying the invention.





FIG. 2

is an exploded perspective view of the switch assembly of the sump pump.





FIG. 3

is an enlarged portion of

FIG. 1

partially cut away.





FIG. 4

is a cross-section view taken along line


4





4


in FIG.


3


.





FIG. 5

is a view taken along line


5





5


in FIG.


3


.





FIG. 6

is an exploded perspective view of an alternative switch assembly.




Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including” and “comprising” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




A pedestal sump pump


10


embodying the invention is illustrated in

FIG. 1

for exemplary purposes. While an important aspect of the invention is the provision of an improved pedestal sump pump, the invention is intended to encompass the use of the switch assembly described herein in other applications.




As illustrated in

FIG. 1

, the sump pump


10


is used within a sump


14


located in a floor


18


. The sump


14


collects water


22


from a foundation


26


. The water


22


within the sump


14


has a variable level


30


. The pump


10


includes a base


34


, and a support post


42


extends upwardly from the base


34


. An electric motor


46


is mounted on top of the post


42


. The motor


46


includes a main housing


48


. The sump pump


10


as thus far described is conventional and need not be described in greater detail.




The pump


10


also includes a water-level-response system


58


. The system


58


includes a float rod or connecting rod


62


. The connecting rod


62


is generally vertically oriented and has thereon spaced upper and lower limit stops


74


,


78


. The system


58


also includes a float


82


mounted on the lower end of the rod


62


. The float


82


is buoyed by the water


22


and moves upward and downward with fluctuations in the water level


30


. Likewise, the connecting rod


62


moves upward and downward with the float


82


. Such a float and connecting rod arrangement is known in the art.




As best illustrated in

FIGS. 2 and 3

, the water-level-response system


58


also includes a switch assembly


86


mounted within the motor housing


48


. The assembly


86


includes a switch housing


90


having a main body portion


94


and left and right (as seen in

FIG. 3

) or front and rear ends


102


,


106


. The switch housing


90


is generally symmetrical about a vertical center plane identified by reference numeral


110


in FIG.


4


. As best shown in

FIG. 2

, a pair of arms


118


extend upwardly from the main body portion


94


on opposite sides of the plane adjacent the left end


102


. Each arm


118


has therein a generally C-shaped recess


126


that opens rearwardly (toward the right end


106


) and slightly upwardly.




The switch housing


90


also includes a pair of arms


130


that extend upwardly from the main body portion


94


on opposite sides of the plane intermediate the right and left end


102


,


106


. Each arm


130


is generally H-shaped and includes a vertically-oriented, inwardly-opening recess


132


such that the recesses


132


face each other. Each arm also has therein a horizontally-oriented, generally rectangular slot or recess


134


. Each arm


130


also has a forward surface


138


facing the right end


102


.




The main body portion


94


has therein a downwardly-opening microswitch recess


142


. A microswitch


146


, which is further described below, is housed in the recess


142


. Extending downward from the main body portion


94


on opposite sides of the recess


142


are a pair of flexible arms


150


. On the lower end of each arm


150


is an inwardly-projecting, beveled lip


154


. When the microswitch


146


is inserted into the recess


142


, engagement of the beveled lips


154


by the microswitch


146


biases the arms


150


outward until the microswitch


146


is fully inserted, at which point the arms


150


snap back into their original positions and the lips


154


extend below the microswitch


146


, as best shown in

FIG. 4

, to retain the microswitch


146


in the recess


142


.




The switch housing


90


also includes a mounting portion


158


extending from the front end of the main body portion


94


. The mounting portion


158


has therein a downwardly-opening, generally U-shaped recess


162


sized to accommodate a mounting screw


166


such that the switch housing


90


can be mounted within the motor housing


48


with a single screw


166


extending through the recess


162


. In alternative embodiments, the mounting portion


158


may be located elsewhere on the switch housing


90


. In other alternative embodiments, the recess can be replaced with an aperture, other types of fasteners can be used, or any other suitable attachment method can be employed, such as having a projection on the switch housing


90


snap into an opening in the motor housing


48


. The housing


90


could also be attached to a part of the motor


46


other than the housing


48


. The mounting portion


158


also includes a pair of wings or projections


167


each having a rearwardly facing surface


168


(only one is shown in

FIG. 2

) that abuts the outside of the motor housing


48


when the switch assembly


86


is installed in the housing as described below.




The switch assembly


86


also includes a lever


170


with right and left or front and rear ends


174


,


178


. The lever


170


is pivotably mounted on the switch housing


90


in a manner described below such that the lever


170


can be toggled between an on position (partially shown in phantom in

FIG. 3

) and an off position (shown in solid lines in FIG.


3


). The front end


174


of the lever


170


is enlarged and has therein an aperture


182


that slidably receives the connecting rod


62


, but that is smaller than the limit stops


74


,


78


so that the limit stops


74


,


78


cannot pass through the aperture


182


, and thus can pivot the lever


170


. The lever


170


has thereon a pair of oppositely-extending, generally cylindrical pivots


186


each pivotably mounted within a respective recess


126


of a respective arm


118


. The lever


170


pivots relative to the housing about the pivots


186


.




The lever


170


also includes a pair of oppositely-extending retaining


10


projections or “pivots”


190


rearward of the pivots


186


. Each projection


190


is located slightly forward of a respective forward edge


138


of a respective arm


130


(shown in

FIG. 3

) to resist twisting of the lever


170


and rearward movement of the lever (thereby resisting removal of the pivots


186


from the recesses


126


). The rearward end


106


of the lever


170


forms a generally semicylindrical cam surface


194


, the reason for which is explained below.




The switch assembly


86


also includes a retainer clip


198


removably attached to the housing


90


. The clip


198


includes a horizontal cross member


200


and a pair of flexible feet


202


extending downward from opposite ends of the cross member


200


. Each foot


202


slides downward into a respective vertical recess


132


in a respective arm


130


and has thereon an outwardly-projecting, beveled projection


206


that snaps into the slot


134


in the respective arm


130


to secure the clip


198


to the housing


90


. When the clip


198


is secured to the housing in this manner, the feet


202


extend on opposite sides of the lever


170


, and the cross member


200


extends above the lever


170


to limit the pivoting motion of the lever


170


. The clip


198


also includes a flexible spring tab


214


extending downward from the cross member


210


between the feet


202


. The lower end of the spring tab


214


forms a generally semicylindrical cam surface


216


in slidable contact with the cam surface


194


on the end of the lever


170


. The spring tab


214


forces the lever


170


to snap into one of the on and off positions.




The housing


90


, the lever


170


and the retainer clip


198


are preferably injection-molded out of a suitable plastic. In the preferred embodiment of the invention, the housing


90


and the lever


170


are made of Polycarbonate, KOTEC K-30FR, and the retainer clip


198


is made of POM, DUPONT 500P, both of which are known to those skilled in the art. This enables these parts to be made easily and inexpensively.




The microswitch


146


, which is removably mounted in the recess


142


as mentioned above, includes a main body


222


and an operating button


226


projecting from the top of the body


222


such that the lever


170


depresses the button


226


when the lever


170


is in the on position. The microswitch


146


also includes a pair of electrical contacts


230


connected to the motor


46


via wiring. While many suitable microswitches can be used, the microswitch


146


is preferably manufactured by Zippy USA, Inc., Model V3-10L63G1-1.




To assemble the water-level-sensing system


58


, the microswitch


146


is snapped into the recess


142


in the switch housing


90


and the lever


170


is mounted on the switch housing


90


as described above. The retainer clip


198


is then snapped into place over the lever


170


. The switch assembly


86


is inserted into the motor housing


48


through a window


232


in the housing


48


, so that the mounting portion


158


abuts the outside of the housing


48


and the remainder of the switch housing


90


is inside the motor housing


48


. The assembly


86


is then secured to the housing


48


with the screw


166


. Electrical connections are made between the motor


46


and the switch assembly


86


and then the motor housing


48


is closed. The connecting rod


62


is located in the lever aperture


182


with the limit stops


74


,


78


above and below the lever


170


. The limit stops


74


,


78


can be adjusted for the desired high and low water levels


30


in the sump


14


.




When the water level


30


in the sump


14


rises above a predetermined level, the lower limit stop


78


moves the first end


174


of the lever


170


upward, thereby moving the lever


170


from the off position to the on position. The spring tab


214


causes the lever


170


to snap to the on position once the cam surface


194


moves past the center of the cam surface


216


. This movement of the lever


170


causes the lever to engage and depress the microswitch button


226


, thereby closing the circuit and turning the motor


46


on.




As the water level


30


in the sump


14


falls, the float


82


and thus the connecting rod


62


move downward until the upper limit stop


74


contacts and moves the first end


174


of the lever


170


downward, thereby moving the lever


170


from the on position to the off position. The spring tab


214


causes the lever


170


to snap to the off position once the cam surface


194


moves past the center of the cam surface


216


. This movement of the lever


170


causes the lever to disengage the microswitch button


226


, thereby opening the circuit and turning the motor


46


off.




An alternative switch assembly


386


is illustrated in FIG.


6


. Except as explained below, the assembly


386


is substantially identical to the assembly


86


, and common elements have been given the same reference numerals. Instead of the retainer clip


198


, the assembly


386


includes a spring clip


390


to hold the lever


170


in place. The arms


130


are modified to accept the clip


390


. Instead of the recess


162


, the spring housing


90


has therein an aperture


394


through which the screw


166


extends.




Various features of the invention are set forth in the following claims.



Claims
  • 1. A pedestal sump pump comprising:a base; a support post extending upward from the base; a motor mounted on the support post, the motor including a motor housing; and a water-level-response system including a float rod, a switch having a main body and being mounted within the motor housing, and an actuating member operably connected to the switch, the member extending from the motor housing and being operably connected to the float rod, such that a variation in water level moves the float rod and the actuating member and toggles the switch.
  • 2. The pump of claim 1 and further comprising a switch housing removably supporting the main body of the switch.
  • 3. The pump of claim 2, wherein the actuating member is a lever pivotably mounted to the switch housing such that the lever toggles between on and off positions.
  • 4. The pump of claim 3, and further comprising a retaining clip removably mounted on the switch housing for retaining the lever in position.
  • 5. The pump of claim 4, where the retaining clip engages the lever so as to cause the lever to snap into the on and off positions.
  • 6. The pump of claim 4, wherein the switch housing, the lever and the retaining clip are made of injection-molded plastic.
  • 7. The pump of claim 6 wherein the switch housing has therein a recess into which the switch snaps, and wherein the retaining clip snaps onto the switch housing.
  • 8. The pump of claim 1, wherein the switch further includes an operating button, and wherein the actuating member operably connects to the operating button such a variation in water level moves the float rod and the actuating member and toggles the operating button.
  • 9. The pump of claim 2, wherein the switch housing is secured to the motor housing with a single fastener.
  • 10. The pump of claim 9, wherein the switch housing has therein a recess, and wherein the fastener is a screw that extend through the recess and into the motor housing.
  • 11. The pump of claim 10, wherein the motor housing has an outside, and wherein the switch housing includes a mounting portion having therein the recess and abutting the outside of the motor housing.
  • 12. A pedestal sump pump comprising:a base; a support post extending upward from the base; a motor mounted on the support post, the motor including a motor housing; and a water-level-response system including a float rod, a switch mounted within the motor housing, and an actuating member operably connected to the switch, the member extending from the motor housing and being operably connected to the float rod, such that a variation in water level moves the float rod and the actuating member and toggles the switch, wherein the actuating member is a lever pivotably mounted to the switch housing such that the lever toggles between on and off positions; and a retaining clip removably mounted on the switch housing for retaining the lever in position, wherein the retaining clip includes a cross member extending over the lever, and a pair of feet that extend from the cross member and that snap onto the switch housing.
  • 13. A pedestal sump pump comprising:a base; a support post extending upward from the base; a motor mounted on the support post, the motor including a motor housing; and a water-level-response system including a float rod, a switch mounted within the motor housing, and an actuating member operably connected to the switch, the member extending from the motor housing and being operably connected to the float rod, such that a variation in water level moves the float rod and the actuating member and toggles the switch, wherein the actuating member is a lever pivotably mounted to the switch housing such that the lever toggles between on and off positions; a retaining clip removably mounted on the switch housing for retaining the lever in position, wherein the retaining clip engages the lever so as to cause the lever to snap into the on and off positions; and wherein the lever has thereon a lever cam surface, and wherein the retaining clip has thereon a spring tab with a cam surface engaging the lever cam surface so as to cause the lever to snap into the on and off positions.
  • 14. A switch assembly comprising:a switch housing having therein a microswitch recess; a microswitch removably mounted in the microswitch recess; an actuating lever pivotably mounted on the switch housing such that the lever toggles between on and off positions, the lever being operably connected to the switch; a retaining clip removably attached to the switch housing to limit movement of the lever, the clip including a flexible portion contacting the lever to snap the lever into the on and off positions; and wherein the lever has thereon a lever cam surface, and wherein the retaining clip has thereon a spring tab with a cam surface engaging the lever cam surface so as to cause the lever to snap into the on and off positions.
  • 15. The assembly of claim 14 the switch housing including a mounting portion including a screw recess receiving a screw for mounting the switch housing on a structure.
  • 16. The assembly of claim 14, the switch housing including flexible tabs adjacent the microswitch recess to retain the microswitch within the microswitch recess.
  • 17. The assembly of claim 14, wherein the retaining clip includes a cross member extending over the lever, and a pair of feet that extend from the cross member and that snap onto the switch housing.
  • 18. The assembly of claim 14, wherein the switch housing, the lever and the retaining clip are made of injection-molded plastic.
  • 19. The assembly of claim 18 wherein the microswitch snaps into the switch recess, and wherein the retaining clip snaps onto the switch housing.
  • 20. A pedestal sump pump comprising:a base; a support post extending upward from the base; a motor mounted on the support post, the motor including a motor housing having an outside and having therein a window; and a water-level-response system attached to the motor and including a connecting rod with upper and lower ends and including upper and lower limit stops in a spaced-apart relation on the rod, a float mounted on the lower end of the rod, and a switch assembly mounted in the window of the motor housing, the assembly including a switch housing including a first pair of recesses, a second pair of recesses, a microswitch recess, flexible tabs adjacent the microswitch recess, and a mounting portion including a recess, the mounting portion abutting the outside of the motor housing such that the remainder of the switch housing is inside the motor housing, a lever with first and second ends, the lever being pivotably mounted to the switch housing such that the lever toggles between on and off positions, the lever including an aperture in the first end of the lever sized to slidably receive the connecting rod, a pair of pivots each pivotably mounted within a respective on of the first pair of recesses of the switch housing, a pair of projections in slidable contact with the housing to retain the pivots in the first pair of recesses, and a cam surface formed on the second end of the lever, a retainer clip removably attached to the housing and retaining the lever in place, the clip including two feet, each having a projection that snaps into a respective one of the second pair of recesses to removably secure the retainer clip in place, a cross member connecting the two feet, and a spring tab connected to the cross member and including a cam surface slidably contacting the cam surface on the lever, the spring tab causing the lever to snap into the on and off positions as the cam surface on the lever moves past the cam surface on the spring tab, a microswitch removably mounted in the microswitch recess and retained by the flexible tabs, the microswitch including a body, a button contacting the lever, and a pair of electrical contacts connecting the microswitch with the motor, and a single mounting screw extending through the mounting portion recess and into the motor housing for connecting the switch housing to the motor housing.
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Number Name Date Kind
2792467 Hollinshead May 1957 A
3153709 Kraemer Oct 1964 A
3979569 Bilgrei Sep 1976 A
4001533 Conery et al. Jan 1977 A
4295017 Kashima et al. Oct 1981 A
4394553 Feil Jul 1983 A
4404441 MacLaren Sep 1983 A
5076762 Lykes et al. Dec 1991 A