U.S. patent number 3,603,757 [Application Number 04/859,039] was granted by the patent office on 1971-09-07 for adjustable switch device.
This patent grant is currently assigned to Lucerne Products, Inc.. Invention is credited to Edward V. Sahrbacker.
United States Patent |
3,603,757 |
Sahrbacker |
September 7, 1971 |
ADJUSTABLE SWITCH DEVICE
Abstract
A trigger-operated electrical switch for a portable electric
motor-driven tool to control the application of electrical energy
from an energy source to the motor. The switch includes stationary
contaCt elements and a stationary resistance element connected into
an electrode circuit. The switch also includes a contact carrier
having a plurality of movable contact elements which coact with the
stationary contact elements and the resistance element to variably
control the application of the electrical energy to the motor. A
manually actuatable trigger handle is adjustably connected to the
contact carrier to enable selective manual actuation thereof. The
trigger handle is longitudinally adjustable on the contact carrier
to enable the operator to preselect the amount the movable contaCts
may be moved relative to the stationary contact elements and
resistance element and thus control the speed of the motor.
Inventors: |
Sahrbacker; Edward V.
(Brecksville, OH) |
Assignee: |
Lucerne Products, Inc. (Hudson,
OH)
|
Family
ID: |
25329845 |
Appl.
No.: |
04/859,039 |
Filed: |
September 18, 1969 |
Current U.S.
Class: |
200/522; 200/1V;
200/327 |
Current CPC
Class: |
H01H
9/061 (20130101) |
Current International
Class: |
H01H
9/02 (20060101); H01H 9/06 (20060101); H01h
009/06 () |
Field of
Search: |
;200/157 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Jones; H. O.
Assistant Examiner: Vanderhye; Robert A.
Claims
What is claimed is:
1. In a portable electric motor-driven tool having a
trigger-receiving housing aperture, wherein the tool is of the type
adapted to contain a control system capable of varying the speed of
the tool motor in response to a predetermined amount of trigger
movement, a trigger-actuated switch device for mounting in said
aperture, said switch device comprising, a switch casing, an
elongated contact carrier operatively connected to the control
system and mounted for reciprocation in said casing to vary the
motor speed with an outer portion of the contact carrier extending
outwardly of the casing, bias means carried by the casing and
engaged with the contact carrier for urging the same to an extended
position, stop means for preventing movement of the contact carrier
beyond such extended position, a separate and distinct trigger
handle adjustably mounted on the outer portion of the contact
carrier for selective longitudinal movement thereon, and manually
operable means for selectively moving said trigger handle
longitudinally on said contact carrier to predetermined positions
thereon, said trigger having an abutment engageable with the casing
to limit movement of the contact carrier into the casing and
thereby selectively control the motor speed.
2. The structure of claim 1 wherein said manually operable means
includes an adjustment screw rotatively disposed in said trigger
handle and extending into the contact carrier in threaded
engagement therewith, whereby preselected circumferential rotation
of the adjustment screw varies the distance between the trigger
handle and the contact carrier a predetermined amount thereby
selecting a desired motor speed.
3. The structure of claim 1 wherein said bias means includes a
compressed coiled spring disposed between the contact carrier and
the casing.
4. The structure of claim 1 wherein said contact carrier has an
elongated recess in its upper surface, and said casing has a
projection extending into said recess to form said stop means.
5. The structure of claim 1 and further including a reversing
switch mounted on said casing in coacting relation with said switch
device, said reversing switch having a handle extending in a
direction opposite and rearwardly of the trigger handle.
6. The structure of claim 1 wherein the trigger handle has a scale
formed thereon and which coacts with the part of the housing
defining the switch aperture to enable an operator to select a
predetermined motor speed with the switch in its off position.
Description
This invention relates generally to an electrical switch device and
more particularly to an electrical switch device for portable
electric motor-driven tools to control the application of
electrical energy from an energy source to the motor and wherein
the switch device is also manually adjustable to effect a
preselected magnitude of electrical energy to be applied to the
motor with the switch device in its full "on position."
There has long been a need for a simple, efficient,
trigger-actuated switch for variably controlling the motor speed in
portable electric tools and appliances such as, for example, an
electric drill, food mixer and/or similar devices.
The switch device of the invention is intended to be connected in
controlling relation with the appliance and the electrical energy
source to which it is connected, as for example in the handle of
the portable electric tool, so as to be conveniently actuated by
the operator thereof to variably control the application of such
energy to the motor of the tool.
It is therefore a primary object of the present invention to
provide an electrical switch device for controllably varying the
application of electrical energy from an energy source to a
connected load such as an electrical appliance and which switch
device is intended to be manually operable to controllably vary the
application of said energy to the appliance.
Another object of the present invention is to provide a new and
novel electrical switch device for controllably varying the
application of electrical energy from an energy source to a
connected load such as hand-held electric drill, food mixer or like
appliance, and which switch is also adjustable to provide a
predetermined magnitude of energy to be applied to the connected
load when the switch device is in its full "on" position.
A further object of the invention is to provide a trigger-operated
hand-drill switch having adjustable stop means for adjusting the
stroke of the trigger.
A further object of the invention is to provide a portable-tool
switch that is simple in construction, inexpensive to manufacture,
and highly effective in operation.
Additional objects and advantages of the switch device of the
present invention will be apparent to one skilled in the art to
which it pertains and upon reference to the following description
of a preferred embodiment thereof which is illustrated in the
accompanying drawings wherein:
FIG. 1 is a top plan view of an electrical switch device embodying
the present invention;
FIG. 2 is a vertical section of the switch device taken generally
along the line 2--2 as shown in FIG. 1;
FIG. 3 is a side elevational view of the trigger handle or actuator
element of the switch device shown in FIG. 2;
FIG. 4 is a side elevational view of the movable contact carrier or
slide bar shown in FIG. 2;
FIG. 5 is a side elevational view of the adjustable setscrew for
adjustably connecting the trigger element or handle and the contact
carrier;
FIG. 6 is a side view shown partially in cross section and taken
approximately on the line 6--6 of FIG. 1 and additionally showing
an energy-reversing switch module and finger actuator mounted on
top of the switch housing; and
FIG. 7 is a view similar to FIG. 6, but showing the trigger element
in a different adjusted position.
Although the switch of the invention is shown and described herein
with reference to its application in a portable electric drill it
will be understood that it may be used in any application to
variably control the application of electrical energy to an applied
load.
The terms and expressions which have been employed are used as
terms of description, and not of limitation, and there is no
intention, in the use of such terms and expressions, of excluding
any equivalents of the features shown and described or portions
thereof, but it is recognized that various modifications are
possible within the scope of the invention claimed.
Referring now to the drawings, and the with particular reference to
FIG. 2, the switch device of the present invention includes a
switch casing or body 10 which encases a switch mechanism or
control system that is disclosed and claimed in the assignee's
copending application Ser. No. 702,272 entitled Electric Switch and
filed on Feb. 1, 1968, such mechanism including a pair of
stationary contacts 11 and 12 corresponding to contacts 20 and 24
in said copending application. Certain portions of such switch
mechanism will be described herein for a better understanding of
the invention. The switch housing 10 includes an upper portion
identified at 13 and a lower portion identified at 14. The
switching components are disposed in the lower portion of the
housing 14 and are connectable into both sides of the electrical
energy source of a two-line system and which are capable of
simultaneously making and breaking the circuit in each of said
lines. For example, as shown in FIG. 2, there is a conductor line
L1 which is broken so as to permit the insertion of switch contacts
11 and 12 in circuit therewith and, in like manner, conductor L2 is
similarly broken so as to permit its being connected in similar
fashion to a second group of stationary contacts 11', 12' and 13'
corresponding to contacts 52, 52a and 52b in said copending
application and which are disposed on the 11', 12' of 13' housing
so as to coact with a bridging contact of the type that is shown at
15, later to be described.
Thus, the switching component includes basically spaced pairs of
stationary contacts that are disposed in spaced relation to each
other on either side of a centerline extending through to each
other on either side of a centerline extending through the switch
structure as is shown in FIG. 1, one pair of stationary contacts
being identified by the numerals 11 and 12 and the corresponding
opposed group of stationary contacts being identified by the
reference numeral 11', 12' and 13' (FIG. 1).
A bridging contact identified at 15 (and 15') coacts with the
spaced stationary contacts 11, 12 (and 11', 12', 13',
respectively), being movable within the housing in a manner as will
be hereinafter described to bridge across its associated stationary
contacts, thus providing electrical conductivity therebetween.
Thus, as herein shown, the switch device is intended to be
connected into both conductors of a two-line conductor electrical
energy source, one such conductor or line being identified as L1
and the second conductor being identified as L2. Conductor L1 is
seen to be broken and connected one end to each of the stationary
contacts 11 and 12 of the one pair and conductor L2 is similarly
broken and connected one end to each of the corresponding
stationary contacts 11' and 13'.
As is also more thoroughly described in the aforesaid copending
application Ser. No. 702,272, conductors L1 L2 shown in the right
end portion of the switch housing, as shown in FIG. 2, are
connected across the electrical load (motor) to which the switch is
to be operable, whereas the conductors L1 and L2 as shown in the
left portion of the housing are connected to the electrical energy
source, such lines being thus operable to connect the switch device
between the energy source and the connected load.
As shown in FIG. 2, the upper portion of the housing 13 defines a
cavity or upper chamber 20 which, as shown in the instant
embodiment, is somewhat rectangular in configuration and extends
longitudinally of the housing 10.
A slide actuator or contact carrier 25 as best seen in FIG. 4, is
reciprocably disposed within the upper chamber 20, said actuator
being somewhat L-shaped in configuration and having an elongated
base leg 26 integrally formed with an upstanding vertical extending
leg or outer portion 27. The base leg 26 is formed with a pair of
recesses 29, 29' into each of which is disposed one of the contact
carrier or bridging contacts 15, 15', respectively.
As shown in FIG. 4, each recess 29, 29' is somewhat of inverted
T-shaped configuration having an upstanding cavity portion 30, 30'
into which is disposed a suitable spring member 31 which engages
each bridging contact 15, 15' with sufficient force to urge said
bridging contact into pressure engagement with its associated
stationary contacts 11, 12 and 11', 12', 13', respectively, to
effect an electrical connection therebetween.
As heretofore mentioned, the contact carrier 25 is intended to be
disposed within the housing chamber 20 and is of such dimension
with respect thereto as to be freely slidable therein
longitudinally throughout the chamber.
As best shown in FIG. 2, the contact carrier 25 is disposed so as
to locate the bridging contact 15, with one end 35 thereof in
pressure engagement with its associated stationary contact 11. The
opposite contacting end 36 of the bridging contact 15, is shown to
be resting upon the upper portion of a cam 37 formed integrally in
the switch housing 10, such cam being operable to secure the
stationary contacts into their operative position, in that the cam
37 is seen to be extendable over the contacting surface of the
stationary contacts 11 and 12. The aforedescribed bridging
contact-cam structure also applied to the bridging contact 15'.
From this FIG. 2 position, which may also hereinafter be referred
to as the "off" position of the switch device, the slide actuator
or contact carrier 25 may be moved to the right, whereupon the
bridging contacts 15, 15' are carried to the right sufficiently to
have the forward contacting end thereof slide downwardly over the
cam 37 and into engagement with the upper surface of the stationary
contacts 12 and 12', and subsequently with stationary contact
13'.
Variable control of the motor speed is effected by a slide 45 (FIG.
6) which is secured to the contact carrier 25 and which slides over
the resistance strip 46 in operative contact therewith, as
explained in detail in the above copending application Ser. No
702,272.
Thus, reciprocation of the contact carrier 25 in and out of the
casing 10 selectively starts and stops the motor and controls the
speed thereof.
As shown in FIG. 2, the distance that the slide actuator is capable
of being moved into the chamber 20 is identified by the reference
A.
The slide actuator is normally biased outwardly or to the left, as
shown in FIG. 2, so as to be normally disposed in its "off"
position. For this purpose, a suitable resilient or bias means in
the form of a compressed coil spring 39 has its one end suitably
engaging the inner surface of the upper portion of the housing 13
and its opposite ends in like engagement with wall 40 of the
contact carrier 25, whereupon the latter is normally urged
outwardly or to the left of the housing chamber 20 to a normally
"off" position as shown in FIG. 2.
The upper wall of the housing 13 is provided with a downwardly
depending boss or projection 42, which is disposed in a suitable
elongated recess 43 (FIG. 4) which extends along the upper portion
of the leg 26 of the contact carrier 25 and which recess terminates
closely adjacent to the wall 40 of said contact carrier.
In its initial installation, the contact carrier 25 is inserted
within the housing chamber 20. The housing is sufficiently flexible
to permit the contact carrier to be forced therein until the
depending boss or stop means 42 snaps into the elongated recess 43
being thus effective to capture the contact carrier within the
housing chamber 20 and reciprocable therein. Thus, the stop means
42 prevents movement of the contact carrier 25 beyond (as to the
left of) its extended position as shown in FIG. 2.
The instant switch assembly also includes a trigger handle 50 which
is adjustably secured to the contact carrier 25 and is disposed so
as to be operable by the trigger finger of the operator to slide
the contact carrier into the housing chamber 20 and thus operate
the electrical switch components therein.
FOr this purpose, and as best seen in FIG. 2, the trigger handle is
somewhat rectangular in elevation, being formed with a cavity or
opening 55 in its one end, such cavity slidably accommodating the
vertical leg 27 of the contact carrier 25 and the adjoining
connected portion of the leg 26 thereof.
Approximately at the point of juncture between the vertical leg 27
and the horizontal leg 26 of the contact carrier 25, a downwardly
depending rib 57 is integrally formed therewith and is of such
dimension to require the leg 27 to be forced with slight pressure
into the trigger cavity 55 and to enable the rib 57 to enter into
slot 62 formed centrally within the bottom wall 63 of the trigger
element and which slot extends longitudinally therethrough. In this
manner, the contact carrier 25 is snapped into the trigger handle
50 and, by reason of the rib 57 being disposed within the slot 62,
is slidably captured therein so that the two elements are not
separable.
The bottom portion 66 (FIG. 3) of the front wall 60 of the trigger
50 has an aperture 67 intended to accommodate an adjusting setscrew
70, as will now be described.
As best seen in FIG. 5, the adjusting setscrew 70 is provided with
a smooth shank portion 71 formed adjacent its enlarged head portion
72, said shank 71 being formed on its opposite end with an enlarged
boss 73 having a tapered outer wall 74 which tapers downwardly from
the end adjacent the shank 71 to the threaded portion 75
thereof.
The adjustable setscrew 70 is intended to be operatively inserted
within the hole 67 formed in the front wall 66 of the trigger 50,
the trigger being formed of any suitable partially resilient
material, whereby suitable pressure as applied to the enlarged head
72 forces the tapered boss 73 into the hole 67 sufficiently to
temporarily deform the material defining said taper and said hole
to the position wherein the adjusting screw snaps into place and is
capture within the said front wall 66 whereupon the smooth shake
portion 71 is disposed within the hole 67 and is of such dimension
with respect thereto to be freely rotatable therein.
The setscrew threaded shake portion 75 is intended to be threadedly
disposed within an internally threaded hole 76 formed in the
adjacent portion of the base leg 26 of the contact carrier 25.
WIth this assembly, by rotating the engaged head 72 of the
adjusting setscrew 70 sufficiently to threadedly move the threaded
shake portion 75 thereof into and out of the internally threaded
hole 76, the trigger 50 is slidably moved toward and away from the
contact carrier 25. Thus, the setscrew 70 provides manually
operable means for selectively moving the trigger handle
longitudinally on the contact carrier 25.
The trigger 50 has an abutment 80 engageable with the casing 10 at
the point 81 to limit movement of the contact carrier 25 into the
casing and thereby selectively control the motor speed.
Specifically, the maximum adjustment distance between the trigger
handle 50 and the contact carrier 25 is represented by the letters
A' and A'" in FIGS. 2 and 6, and in such figures A" represents the
total distance the contact carrier can travel at such maximum
adjustment. In FIG. 7, A' and A'" represent the minimum adjustment
distance between the trigger handle 50 and the contact carrier 25,
and in such figure A" represents the distance the contact carrier
can travel at such minimum adjustment.
It is oftentimes desirable to preset the switch so that upon its
subsequent operation a preselected motor speed may be obtained.
For this purpose a scale identified at 83 is formed or scribed by
any suitable method on the outer surface of the trigger handle 50,
and is intended to cooperate with an edge E of the aperture formed
in the handle of the tool casing C into which the switch is
disposed.
As best seen in FIG. 3, the outer limits of the scale 83 are
identified at F and S, F signifying a fast motor speed and S for
slow motor speed.
As previously described, the trigger handle 50 may be adjustably
moved longitudinally along the contact carrier 25 by turning the
adjusting screw 70 in the appropriate direction. In this manner,
the handle 50 may be preset into an adjusted position on the
carrier 25 while the latter is in its off-switch position. In this
position, the scale 83 will likewise be positioned with respect to
said casing edge E to identify the expected motor speed to be
obtained when the trigger handle 50 is depressed into the tool
casing.
FIG. 6 shows a reversing switch 85 mounted on the casing 10 and
having a handle 86 extending in a direction opposite to or
rearwardly of the trigger handle 50. The operative details of such
switches are described in U.S. Pat. No. 3,467,801.
The trigger handle 50 includes a longitudinally extending arm 87
having a sidewardly projecting lug 88 on the end thereof which is
engaged by the outwardly biased pushbutton 89 to lock the trigger
handle-contact carrier combination in "on" position as described in
detail in the aforementioned application Ser. No. 702,272.
* * * * *