US3727021A

US3727021A - Rotary switch housing

Info

Publication number: US3727021A
Application number: US00265268A
Authority: US
Inventors: F Preis
Original assignee: LASKO METAL PROD Inc
Current assignee: LASKO METAL PROD Inc
Priority date: 1972-06-22
Filing date: 1972-06-22
Publication date: 1973-04-10
Anticipated expiration: 1990-04-10

Abstract

A housing for a rotary switch having a rotary shaft in which the housing walls are integrally formed of an insulated plastic material, a boss is integrally formed on the top wall of the housing for tightly receiving the rotary shaft, and a knob is fixed to the top of a spindle having a radial skirt terminating in an annular rim at a level below the top of the boss. The switch housing may be further characterized by having a pair of opposed integrally formed upstanding latching ears adapted to engage a pair of mating latch holes in a horizontal mounting plate or wall to hold the switch housing in place against the bottom surface of the wall.

Description

United States Patent 1 1 Preis 1 Apr. 10, 1973 [5 ROTARY SWITCH HOUSING 3,469,051 9 1969 Yamada et al ..200/l68 c [76] Inventor: Fritz Preis, c/o Lasko Metal Products, IllC., PO. Box 130, 3 Franklin, Tenn 3.7064 Attorney-Harnngton A. ackey [22] Filed: June 22, 1972 [57] ABSTRACT [21] Appl. No.: 265,268 A housing for a rotary switch having a rotary shaft in which the housing walls are integrally formed of an in- 2 sulated plastic material, a boss is integrally formed on 1 U S Cl 200/168 200/168 C the top wall of the housing for tightly receiving the ro- [51] Int. Cl. ..H0lh 9/04 t haft d kn f d t th t f d] [58] FieldofSearch ..200/l68 o, 168C t e 6 having a radial skirt terminating in an annular mm at a 5 6] References Cited level below the top of the boss.

The switch housing may be further characterized by UNITED STATES PATENTS having a pair of opposed integrally formed upstanding 3,456,227 7 1969 Paine et a1. ..200/l68 G x latching ears adapted to engage a P Of mating latch 3,277,739 10/1966 Morse 1 ..200/l68 G x holes n a horizontal m unting plate or wall to hold 3,395,260 7/1968 Hamlin ..200/168 G the switch housing in place against the bottom surface 3,406,367 10/1968 Maguire ..200/168 G X of the wall, 3,360,627 12/1967 Wessel .f. ..200/l68 G 3,337,708 8/1967 Cerveny et a] ..200/ 168 C 2 Claims, 4 Drawing Figures ROTARY SWITCH HOUSING BACKGROUND OF THE INVENTION This invention relates to a rotary switch housing, and more particularly to an insulated plastic rotary switch housing.

Rotary switch housings are numerous in the art. Switch housings made of insulated plastic material are also known.

However, by the very nature of switch housings,

there must be an opening therethrough for rotatably receiving the rotary shaft for actuating the rotary switch. Thus, even where the housing is made of a minimum number of wall sections, and where care is takenin sealing the joints between the wall sections, nevertheless it is difficult to seal the rotary shaft opening through the housing and still permit the shaft to rotate.

SUMMARY OF THE INVENTION a hole therethrough for tightly and rotatably receiving the shaft. Mounted on top of the rotary shaft is an enlarged knob having a solid top surface and an annular skirt declining radially outward to form an annular rim spaced radially outward a substantial distance from the boss, with the level of the annular rim being below the top of the boss.

The switch housing made in accordance with this invention preferably is provided with a pair of upward projecting slightly resilient latch ears the bottom ends of which are integrally formed with the sides or bottom wall of the switch housing. The upper ends of the latch ears have upward inwardly cammed top surfaces and lower outwardly directed catch ledges. Thus, the switch housing is adapted to fit flush against the bottom surface of a horizontal mounting wall or plate having an opening in the center for receiving the upper projecting boss and having a pair of laterally opposed latch openings through which the latch ears may be cammed and held in latched position.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a side elevation of the switch housing made in accordance with this invention;

FIG. 2 is a section taken along the line 2--2 of FIG.

FIG. 3 is a fragmentary top plan view of a horizontal mounting wall to the bottom of which is secured in latched position, the switch housing disclosed in FIG. I; and

FIG. 4 is a section taken along the line 4-4 of FIG. 3, with the switch housing disclosed in full side elevation and the knob disclosed in phantom.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings in more detail, the switch housing 10 made in accordance with this invention basically comprises a switch capsule 11, a shaft boss 12, a knob 13, and preferably a pair of latch ears l4 and 15.

The capsule 11 includes a top wall 17 and a continuous side wall 18 which are integrally formed, such as by molding, from an insulated, self-extinguishing plastic material, such as Lexan 2014-1 16.The shaft boss 12 is also integrally molded with the top wall 17 and forms a cylindrical shaft hole 20 extending entirely through the boss 12 to communicate with the cavity 21 within the capsule 1 1.

The capsule 11 also includes a bottom wall 22 which is molded separately, but is provided with holes of different sizes for fitting over corresponding locater

plastic pins

23 and 24 integrally formed with the side wall 18. After the bottom wall 22 is fitted over the

locator pins

23 and 24, the pins are flattenedby fusing to completely seal the locator pin holes and completely seal the bottom wall 22 in position to encapsulate rotary switch element 25 and the stationary switch contacts 26.

Conductor openings 27 are provided in the wall 18 to permit the insertion of electrical conductors 28 therethrough for connection with stationary contacts 26. After the conductors 28 are inserted through the conductor holes 27, the holes 27 are appropriately sealed by any type of plastic insulating fusible material.

The rotary switch element 25 is fixed to the bottom of the rotary shaft 30. The rotary shaft 30 is tightly and rotatably received within the shaft hole 20 of the boss 12 and is also adapted to project above the top surface 31 of the boss 12. Fixed to the top end portion of the shaft 30 is a depending socket 32 formed in the bottom surface of the knob 13.

The knob 13 has a solid top surface 33 and forms an annular skirt 34 which declines radially outward to terminate in an annular rim 35. It is an important feature of this invention that the rim 35 is not only spaced radially outward a substantial distance from the boss 12, but that the level of the bottom of the rim 35 is below the top surface 31 of the boss 12. It will also be noticed, particularly in FIGS. 1 and 2, that the rim 35 projects radially outward beyond the periphery of the side wall 18 of the capsule 11. Thus, the solid top surface 33 of the knob 13 as well as the outward declining skirt 34 protects, not only the boss 12, but the entire switch capsule 11 from the elements of the weather, and particularly rain, even when the rain is directed downward at angles of as much as 45, or more. Thus, the protective covering provided by the knob 13 reduces the concern about sealing the joints between the shaft hole 20 and shaft 30 against the penetration of rain, snow, or moisture in vapor form.

With reference to FIGS. 3 and 4, the switch housing 10 is disclosed mounted upon a horizontal mounting wall or plate 37. The plate 37 includes a boss hole 38 large enough to receive the upward projecting boss 12 when the capsule 11 is fitted flush up against the bottom surface of the mounting plate 37. The boss hole 38 may converge as disclosed in FIG. 3 to receive an upward projecting locater pin 39 integrally formed on the top wall 17, if desired.

Also formed through the mounting plate 37 on opposite ends of the boss hole 38 are a pair of

latch openings

40 and 41 in substantial vertical alignment with the

respective latch ears

14 and 15, when the boss 12 is inserted through the boss hole 38. Each latch ear l4 and has a bottom end portion 42 integrally formed with the outer surface of the capsule 11, such as being fused to or molded with the bottom wall 22, a disclosed in FIGS. 1 and 4. The

ears

14 and 15 project upward spaced from the edge of the capsule l1 and above the top wall 17. The upper end or head of each

latch car

14 and 15 has an upward and inward inclined surface 44 adapted to cam upward against the edge of each

slot

40 and 41 to force the respective latch ears l4 and 15 inward. The head of each

latch ear

14 and 15 is substantially hook-shaped and provided with a horizontal bottom catch ledge 45 directed outward to engage over the top surface of the mounting wall 37 as each cam head clears the

respective catch holes

40 and 41.

The spacing between the top surface of the top wall 17 and each catch ledge 45 is substantially equal to the thickness of the mounting plate 37, to provide a secure fit of the top wall 17 against the bottom surface of the mounting plate 37 when the switch housing 10 is in latched position.

If desired, the outer edge of the latch slot 40 may be provided with an outward directed recess 47 which extends beyond the outer edge of the cam surface 44 of the latch ear 14, as best disclosed in FIG. 3. Thus, a screwdriver may be inserted down through the opening 47 to urge the cam head 44 of the latch ear l4 inward to facilitate removal of the latch ear 14 from the latch hole 40 to permit unlatching and removing the switch housing 10 from the plate 37, if desired.

As disclosed in FIG. 4, the knob 13 extends radially outward a distance sufficient to actually protect the

holes

38, 40 and 41 to a limited degree from rain, snow, and even dust.

Mounting wall or plate 37 could be the top wall in a housing for a fan electrically connected to the switch housing 10 for control by the rotary switch element and knob 13. The wall 37 could be the top wall of the housing for any type of electrical appliance controlled by the rotary switch element 25 in the switch housing 10.

What is claimed is:

1. A housing for a rotary switch having a rotary shaft,

comprising:

a. a top wall, a bottom wall and a circumferential side wall, integrally formed of an insulated plastic material and encasing said switch,

b. openings in at least one of said walls for receiving electrical leads for connection to said switch,

c. a boss having a top surface integrally formed on,

and projecting upward from, said top wall,

d. said boss having an elongated cylindrical shaft hole therethrough normal to said top wall and adapted to tightly receive said shaft for rotary movement, said shaft projecting above the top of said boss,

. a knob having a solid top surface and an annular skirt extending radially outward to define an annular rim, f. means securing the bottom of said knob concentrically to the top of said shaft so that the level of said rim is below, and spaced radially outwardly of, the top surface of said boss.

2. The invention according to claim 1 in which said top wall is flat so that said switch housing is adapted to fit flush against the bottom surface of a relatively thin, horizontal, mounting wall having a hole therethrough to permit said boss to project upward therethrough, and having a pair of cam slots spaced apart a distance slightly greater than the transverse dimension of the switch housing and on opposite sides of the boss hole, said housing further comprising a pair of upstanding latch ears having bottom end portions integrally formed with said bottom wall, said latch ears projecting upward and terminating in latch hooks spaced above said top wall, each latch hook having a laterally outward projecting bottom ledge and upper converging cam surfaces, the material of said latch ears being sufficiently resilient to permit inward flexing of said latch ears so that said upper cam surfaces will cam upward and inward through said latch openings and said bottom ledges will catch over the edges of said latch openings to lock said switch housing against the bottom of said mounting wall.

Claims

1. A housing for a rotary switch having a rotary shaft, comprising: a. a top wall, a bottom wall and a circumferential side wall, integrally formed of an insulated plastic material and encasing said switch, b. openings in at least one of said walls for receiving electrical leads for connection to said switch, c. a boss having a top surface integrally formed on, and projecting upward from, said top wall, d. said boss having an elongated cylindrical shaft hole therethrough normal to said top wall and adapted to tightly receive said shaft for rotary movement, said shaft projecting above the top of said boss, e. a knob having a solid top surface and an annular skirt extending radially outward to define an annular rim, f. means securing the bottom of said knob concentrically to the top of said shaft so that the level of said rim is below, and spaced radially outwardly of, the top surface of said boss.