U.S. patent number 3,635,512 [Application Number 05/048,068] was granted by the patent office on 1972-01-18 for lock for knobs and the like.
Invention is credited to Wray Carl Hansen.
United States Patent |
3,635,512 |
Hansen |
January 18, 1972 |
LOCK FOR KNOBS AND THE LIKE
Abstract
A lock for releasably securing a pushbutton, knob or the like to
an actuator, such as a rod or shaft, comprising a member
constructed of resilient metallic sheet material having prongs or
barbs embedded into the knob for preventing its removal from same
and including a resilient cantilevered locking lever having an
aperture therein through which the rod extends which jams and
frictionally engages the rod but which may be manually flexed to a
release position. The increasing embedment or indentation of the
knob by the prongs, with time and wear, is ineffective to change
the resilient urge of the lever from its initial position of
assembly, thereby maintaining the locking effect unchanged.
Inventors: |
Hansen; Wray Carl (Arvada,
CO) |
Family
ID: |
21952567 |
Appl.
No.: |
05/048,068 |
Filed: |
June 22, 1970 |
Current U.S.
Class: |
292/353; 403/365;
403/377 |
Current CPC
Class: |
G05G
1/12 (20130101); Y10T 403/7077 (20150115); Y10T
403/7047 (20150115); Y10T 292/869 (20150401) |
Current International
Class: |
G05G
1/12 (20060101); G05G 1/00 (20060101); E05b
003/04 () |
Field of
Search: |
;292/353,348,349,359
;287/53H ;74/548,553 ;16/11R,114R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Mautz; George F.
Assistant Examiner: McCarthy; Edward J.
Claims
What is claimed is:
1. A knob lock for securing a knob having an open-ended
longitudinally extending noncircular aperture of substantially
uniform cross section, to an end of a rod having a corresponding
cross section, by relative axial movement between the knob and rod,
said aperture being disposed between a pair of longitudinally
extending channels in the knob, one on each side of said aperture
and communicating therewith, one wall of said channels and one wall
of said aperture being disposed in substantially the same plane,
forming a common wall, said channels each having another wall
disposed in spaced relation to said common wall, forming locking
walls, said knob lock comprising:
a. an integral member formed from resilient metallic sheet material
by blanking, shearing and bending operations;
b. said member comprising a flat base portion having one face
adapted to abut said common wall, the central portion of its other
face adapted to be disposed adjacent and parallel to a flat portion
on the rod;
c. at least one prong adjacent each lateral edge of the base
portion, sheared and bent at an acute angle away from the plane of
the base portion, its free end being pointed in a direction toward
the open end of the knob aperture and having a right angular corner
adapted to resiliently engage the corresponding locking wall
adjacent thereto for preventing separation of the member from the
knob and for urging said one face into engagement with said common
wall; and
d. a terminal leg extending from one end of said base member having
an aperture therein corresponding to the cross section of the rod
and through which the rod is adapted to extend, for releasably
securing the terminal leg to the rod.
2. A knob lock in accordance with claim 1 wherein the aperture in
the terminal leg is rectangular.
3. A knob lock in accordance with claim 1 wherein the aperture in
the terminal leg is isoceles triangular.
4. A knob lock is accordance with claim 1 wherein the aperture in
the terminal leg is circular with a chordal flat portion.
5. A knob lock in accordance with claim 1 in combination with said
knob and rod.
6. The combination of claim 5 wherein the aperture in the terminal
leg and in the knob are rectangular.
7. The combination of claim 5 wherein the aperture in the terminal
leg and in the knob are isoceles triangular.
8. The combination of claim 5 wherein the aperture in the terminal
leg and in the knob are circular with a chordal flat portion.
9. A knob lock in accordance with claim 1 including at least two
like prongs spaced along each lateral edge of the base portion.
10. A knob lock in accordance with claim 1 including a tab at the
inner end of the base portion, bent away from its plane to
substantially a right angle, its free end terminating at a position
within said aperture and in nonlocking engagement therewith,
forming an abutment for inserting the lock into the knob, said
prongs forming the sole lock therewith.
Description
BACKGROUND OF THE INVENTION
In the art of fastening manual control members, such as
pushbuttons, knobs, dials, handles, and the like, to shafts or
rods, it has been the practice to employ resilient fasteners which
interlock the parts in various manners to secure them together.
Usually, they may also be released to permit removal of the manual
member from the rod or shaft to facilitate assembly or disassembly
of other parts with which the member is associated. Push button
radios, other electrical devices, and household appliances are
exemplary of but a few of the myriad applications of such devices.
The manual members are often formed from nonmetallic materials,
such as plastics, and the like, which may be moulded in dies with
the attendant minimization of cost of manufacture. Since such
materials are relatively soft, compared with metals, difficulties
have been experienced in constructing satisfactory fasteners or
locks, particularly where they employed locking prongs or barbs
which embedded into the softer material. In one prior construction,
for example, and over which the present invention constitutes an
improvement, the prongs continued to deepen their embedment into
the soft manual member and during this contained deepening of
embedment the lock with the rod or shaft became less effective.
SUMMARY OF THE INVENTION
A lock for releasably securing a pushbutton, knob or the like to
its actuating shaft or rod characterized by a member formed from
flat metallic spring material having resilient prongs slidable into
slots or recesses in the knob which engage and indent the knob to
prevent removal of same, further characterized by a cantilevered
and apertured arm which engages the rod and frictionally engages
and jams same to prevent undesired removal but permits removal by
manually moving the cantilevered arm to a release position. The
orientation of the prongs relative to the knob is such that upon
continued indentation or embedment of the knob by the prongs the
arm maintains substantially the same locking force on the rod.
It is thus a principal object of the present invention to provide a
locking device, particularly for use with relatively soft knobs and
the like, which retains its optimum locking action to the rod
regardless of changes of orientation of its parts resulting from
progressive and increasing embedment of its locking prongs or
barbs.
Further objects, advantages, and salient features will become more
apparent from the detailed description to follow, the appended
claims, and the accompanying drawing to now be briefly
described.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan of a spring lock for securing a knob to a
shaft;
FIG. 2 is a side elevation and partial section taken on line 2--2,
FIG. 1;
FIG. 3 is an end elevation as viewed in the direction of arrow 3,
FIGS. 1 and 2;
FIG. 4 is an end elevation of a knob as viewed in the direction of
arrow 4, FIG. 5;
FIG. 5 is a section taken on line 5--5, FIG. 4;
FIG. 6 is a side elevation and section, like FIG. 2, illustrating a
shaft and lock in locked relationship;
FIG. 7 is a side elevation and section, like FIG. 6, after assembly
into the knob, also illustrating a tool for removing the knob;
and
FIGS. 8 and 9 are sections of alternative forms of actuator
rods.
DESCRIPTION OF PREFERRED EMBODIMENTS
Referring now to the drawings, the subject of the invention
comprises, briefly, a spring lock L for securing a knob K to a
shaft or rod R which may be of various cross sections, the assembly
of the three parts being illustrated in FIG. 7 wherein rod R is
rectangular.
As best illustrated in FIG. 4, the knob is provided with an
inverted T-slot 10 having a rectangular portion 12 and a pair of
rectangular wing portions 14,14 joining same and projecting
outwardly therefrom. A recess 16, somewhat larger than the I-slot,
is provided at the open end of the knob which receives a portion of
lock L to be subsequently described in detail. A notch 18 in the
wall of the knob provides access to the lock for removing the knob
from the shaft, the manner of which will also be subsequently
described.
Referring now to FIGS. 1 to 3, the lock comprises a spring metal
member, such as spring steel, spring bronze, or the like, which is
formed from flat stock by conventional blanking, punching and
bending operations. It comprises a flat base portion 19 having an
upturned tab or abutment 20 at one end and a pair of upturned barbs
or prongs 22,22 adjacent opposite lateral edges of same. Near the
other end, the base portion is joined to a downwardly extending
U-shaped neck portion 23, serving as a spring, the outer free leg
24 of which is disposed angularly to the base member and provided
with a rectangular aperture 26, having dimensions to permit rod R
to slide through the aperture, preferably with small clearance,
particularly with respect to the thickness or narrow dimension of
the rectangular rod.
Referring now to FIG. 6, which illustrates rod R locked to lock L,
the lower surface of the rod is in facial engagement with base 19
and leg 24 has been rotated slightly in a counterclockwise
direction from its relaxed position so that the clockwise moment on
leg 24 jams the upper and lower edges of aperture 26 into locking
engagement with the rod. This results since in the relaxed position
of lock L the lower edge of aperture 26 is displaced slightly to
one side of the plane of base portion 19. Due to the angularity of
leg 24 to base portion 19, the tendency for leg 24 to rotate
clockwise reduces, in effect, the vertical distance between the
lower and upper edges of aperture 24. Conversely, when arm 24 is
manually rotated in a counterclockwise direction, the vertical
distance is increased, unlocking the edges of aperture 26 from
engagement with the rod. A locking action may be attained by
displacing the lower edge of aperture 24, relative to the plane of
the top surface of base portion 19, in a direction below or above
same. Displacement in a direction above the plane, however, is
preferred since this has been found to produce the more desirable
locking and unlocking action. FIG. 7 illustrates the same
relationship of parts as FIG. 6 but with lock L locked to knob K.
The dotted position of arm 24 illustrates the manual
counterclockwise movement to unlocked position, referred to.
The height of upturned prongs 22 is such that when they enter slots
14,14 they are sprung slightly so that their free ends resiliently
engage surfaces 30,30 of slots 14,14, resisting removal. If the
knob is constructed of relatively soft material, such as plastic,
the prongs form slight indentations in these surfaces forming a
permanent lock of the spring lock to the knob.
The importance of disposing barbs 22 in the position disclosed can
be better understood by reference again to FIG. 7. In the position
shown, U-shaped portion 23 is under a counterclockwise moment, due
to flexure of spring 23 from its previous position, as shown in
FIG. 6. This rotates the lower face of base 19 into tight facial
engagement with the surface 32 which it abuts. Since there are no
prongs or barbs extending from the lower face there cannot be any
embedment which would permit it to change position, hence leg 24
also is permanently retained in its initial position. In contrast,
if the prongs projected from the lower face, they would continue to
embed into the soft knob, permitting the base 19 to rotate
counterclockwise, which as will be apparent, would change the
initial angle of assembly between the base 19 and leg 24 thus
reducing the moment and reducing the locking action between the leg
and actuating rod.
The knob and its attached spring lock may be removed from the rod,
when desired, by straining leg 24 in the direction opposite to the
direction in which it tends to move. Thus, by inserting a hook
shaped tool T into notch 18 and engaging the free end of leg 24 it
may be moved to the dotted position of FIG. 7, releasing its
engagement with the rod. As soon as it is released, continuation of
the pull on leg 24 slides the knob and spring assembly along the
rod to a disconnected position.
As so far described, rod R is rectangular in cross section, this
being a common expedient when it can be readily punched from flat
stock. The cross section may be otherwise; however, FIG. 8
illustrating a rod R.sub.1 which is constructed from round stock
with a flat on same and FIG. 9 illustrating a rod R.sub.2 of
triangular shape. As will be apparent, aperture 26 will then be
punched to a corresponding shape and recess 12 similarly formed to
receive the rod and spring lock.
* * * * *