U.S. patent number 3,594,072 [Application Number 04/882,233] was granted by the patent office on 1971-07-20 for head-holding fixture for use with visual instruments.
This patent grant is currently assigned to Biometrics, Inc.. Invention is credited to Jens Duborg, James E. Feather.
United States Patent |
3,594,072 |
Feather , et al. |
July 20, 1971 |
HEAD-HOLDING FIXTURE FOR USE WITH VISUAL INSTRUMENTS
Abstract
A head-holding fixture for use with visual instruments including
a frame with a laterally extending bar for engaging the forehead
and a moveable chin support for pivoting the head about the
laterally extending bar and/or changing the head elevation with
respect to it so as to provide both height and tilt adjustment.
Inventors: |
Feather; James E. (Natick,
MA), Duborg; Jens (Pinehurst, MA) |
Assignee: |
Biometrics, Inc. (Cambridge,
MA)
|
Family
ID: |
25380171 |
Appl.
No.: |
04/882,233 |
Filed: |
December 4, 1969 |
Current U.S.
Class: |
351/245; 248/118;
297/392 |
Current CPC
Class: |
A61B
3/00 (20130101); A61B 3/0083 (20130101); A61B
3/113 (20130101) |
Current International
Class: |
A61B
3/00 (20060101); A61B 3/113 (20060101); A61b
003/00 () |
Field of
Search: |
;351/38 ;250/50
;297/391,392,397,404 ;248/118 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Schonberg; David
Assistant Examiner: Sacher; Paul A.
Claims
What we claim is:
1. A head-holding fixture comprising,
a tubular frame including a laterally extending bar for engaging
the forehead,
an adjustable chin rest, means for mounting and adjusting said chin
rest on the frame,
said adjusting means including means for providing a single
adjustment for both the head height and tilt with respect to the
frame,
and restraining means connected to the frame proximate the
laterally extending bar for resisting lateral movement of the head
in the frame.
2. A head-holding fixture in accordance with claim 1 further
characterized by said mounting means including a bracket that
carries the chin rest secured on each side of the frame,
said adjusting means including clamps, one on each side of the
frame for engaging the bracket,
said adjusting means also including a fastener on each clamp to
pivot, raise and lower the bracket on the frame.
3. A head-holding fixture in accordance with claim 1 further
characterized by said restraining means comprising a pair of
eccentrically mounted discs on each side of the frame for engaging
the sides of the head by their edges,
said discs being rotatable to move their edges toward and away from
each other.
4. A head-holding fixture in accordance with claim 2 further
characterized by said bar for engaging the forehead extending
laterally across the frame and establishes a tilt axis for the head
just above the eyes,
and said adjusting means enabling the chin rest to move up and
down, and back and forth with respect to the laterally extending
bar.
5. A head-holding fixture in accordance with claim 4 further
characterized by said frame comprising a pair of substantially
vertical side posts and a pair of forwardly extending arms attached
to the tops of the side posts and joined together by the laterally
extending bar,
said discs being mounted for rotation on the forwardly extending
arms,
said adjusting means being secured to the frame rearwardly of the
discs.
Description
This invention relates to head-holding fixtures and more
particularly comprises a simple, relatively inexpensive fixture for
supporting the head in a fixed position.
Most ophthalmic instruments such as slit lamps, keratometers,
visual field plotters, etc. utilize head-holding fixtures of one
sort or another. These fixtures have in the past had one or more of
the following disadvantages:
A. they required at least two types of adjustment to position the
head. Separate adjustments were provided to establish the chin
height and the degree of forehead tilt.
B. they incorporated an adjustment system which tilts the head
about a fixed chin rest. Because the chin remained relatively
stable during such an adjustment, the eyes then moved over a
considerable range in spite of the fact that when using instruments
which focus on the eyes should remain relatively stable during
adjustment.
C. they did not include suitable means for restricting lateral head
movement.
D. they were relatively complex and expensive, and required a
substantial number of machined parts.
One object of this invention is to provide a head-holding fixture
which provides a single adjustment for both head height and
tilt.
Another object of this invention is to provide a head-holding
fixture with a tilt adjustment which holds the eyes in a relatively
stable position.
Yet another object of this invention is to provide a head-holding
fixture which has simple means for restricting lateral head
movement.
Yet another object of this invention is to provide a head-holding
fixture which is composed of few parts, all of which are relatively
simple and inexpensive to fabricate.
To accomplish these and other objects, the head-holding fixture of
this invention includes a frame having a bar for engaging the
forehead. A chin rest is mounted on the frame and is moveable both
up and down, and back and forth, so as to pivot, raise, and lower
the head with respect to the bar at the forehead. Restraining means
are connected to the frame, which engage the sides of the head to
resist lateral movement.
In the drawings:
FIG. 1 is a perspective view of a head-holding fixture constructed
in accordance with this invention and showing the way it may be
associated with an eye movement monitor;
FIG. 2 is a side view of the head-holding fixture as it may be
mounted on a table; and
FIG. 3 is a front view of the fixture, both FIGS. 2 and 3 showing
the way the head is positioned by it.
In FIG. 1 the head-holding fixture 10 of this invention is shown
mounted on the end 12 of an eye movement monitor 14. The eye
movement monitor 14 is only exemplary of the type of visual
instrument with which the head-holding fixture of this invention
may be used, and it is to be understood that in no way limits the
scope of this invention. Such head-holding fixtures are often
required by scientists, ophthalmologists, optometrists, etc. in
either the utilization or examination of a subject's eyes and while
in FIG. 1, the fixture is shown secured to the monitor 14, it is to
be understood that it may be supported independently of other
instruments, and for example, be clamped to a table as shown in
FIG. 2. The head-holding fixture of this invention provides a
comfortable, simple, reliable, and easily operable device.
The fixture 10 has a base 16 which includes a cylinder 18 having an
extendable stem 20 depending from it, which in turn carries a foot
22. The stem 20 may be drawn downwardly from the cylinder 18 so as
effectively to raise the entire assembly. A height adjustment knob
24 carrying a pin (not shown) may selectively be positioned in
notches (not shown) provided in the stem so as to hold the stem in
any selected extended position. A friction arrangement may replace
the pin and notches and serve the same purpose. When the fixture 10
is rigidly secured to an instrument, as is the case in the
embodiment shown, it is apparent that when the stem 20 is extended
the entire assembly is effectively tilted about the legs 25 on end
26 of the machine and end 12 is elevated.
The cylinder 18 supports a generally triangular plate 28 at the
top, which in turn carries a tubular frame member 30. The tubular
frame member 30 includes a pair of legs 32 and 34 whose lower ends
are secured to the rear corners 36 and 38, respectively, of plate
28. The lower portion of the legs 32 and 34 diverge in an upwardly
direction so that the vertical sections 40 and 42 are far enough
apart so that the head of the subject may fit between them.
Generally horizontal forwardly extending arms 44 and 46 are secured
to the tops of the vertical sections 40 and 42 and they in turn are
joined by a laterally extending horizontal bar 48, which is
designed to engage the forehead of the subject about 11/2 inches
above the eyes. This is suggested clearly in FIGS. 2 and 3.
A pair of generally vertical plates 50 and 52 are welded or
otherwise secured to the bend in the frame member 30 where the
vertical sections 40 and 42 join the horizontal forwardly extending
arms 44 and 46. These plates serve as the base for clamps 54, which
pivotally carry U-shaped bracket 56 which bears the chin rest 58.
The clamps 54 are controlled by locking knobs 60; and when the
clamps are loosened, the U-shaped bracket 56 may be raised and
lowered on the plates 50 and 52, as well as be pivoted on those
plates about the axis of the locking knobs 60. To facilitate
adjustment of the bracket 56, a handle 62 is provided adjacent the
chin support 58, which may readily be grasped by an operator so as
to lift and/or pivot the bracket.
A pair of camlike discs 64 are eccentrically mounted on the
forwardly extending arms 44 and 46 of the frame member 30 forward
of the plates 50 and 52. The discs 64 rotate on the arms 44 and 46
and their peripheries move toward and away from one another
depending on their particular angular positions. Because they are
eccentrically mounted, it is apparent that rotation does effect the
distance between them. The discs are intended lightly to contact
the subject's temples to prevent lateral motion of the head when in
position within the frame 30.
The operation of the head-holding fixture is as follows: The
subject positions his head within the bracket 56 with his forehead
resting against the lateral bar 48 so that the center point of the
tubing rests about 11/2 inches above the eyes and is centered
between them and establishes a tilt axis for the head just above
the eyes. The subject is then asked to tilt his head until he is
comfortable, and the chin rest is tilted and/or moved up or down to
support his chin in that position. The locking knobs 60 are then
tightened and the discs 64 are rotated so that they lightly contact
the subject's temples and prevent lateral motion of the head. With
these easy adjustments the examination or test of the subject's
eyes may begin.
While the fixture shown in the drawing is intimately associated
with and connected to an eye movement monitor 14, it is to be
understood that the fixture is wholly independent of the monitor
and may be used with a variety of different devices. Moreover, the
cylinder 18 may independently be clamped to a table or other
support so that it is not in any way connected to the particular
device with which the subject is to be examined or tested.
* * * * *