1. business and industrial
2. energy
3. oil

Feb. 21, 1950
H. N. DlMlcK
2,498,256
INTERMITTENTLY OPERATED VACUUM HORN
Filed July 24, 1945
2 sheets-'sheet 1
\
Feb.. 21, 1950
2,498,256
H. N. DlMlcK
INTERMITTENTLY OPERATED VACUUM HORN
2 Sheets-Sheet 2
Filed July 24, 1945
:gli
E
57%
ß T T Ü R. N E y
2,498,256
Íjatentefl Feb. v21, 195.0
UNITED STATES PlßgTlEZNTj OFFICE
¿498,25€
INTERMITTENTLY OPERATED
VACUUM HORNl
HenryÀ N. D'îmiek‘, Portland," oreg'.; assig'nor to'
Hyster Company, Portlandg‘O'i‘egr, a corporation
of `Oregon A'
Application July 24, 1945», iSerialfNo. 606,785
5'Claims.
1_.
`This invention relates'to a novel Y`vaou1iin‘horn
for'producing an audible Warning signal.
The general 'object of 'the invention' is toïpro
vide-a vacuum horn for'vehicles, and the like,
whichl does not employ‘delicate «parts or mecha
nism's‘requiring 'frequent adjustment or replace->
ment,V which lis rugged and reliablev in'operation',
(C15116L22) '
2
frequent intervals adequately to Warn all"vvö`rlí--Í
men in the vicinity Withoì'ltcl‘eátihg'the a'i’iîioyi
ance of a constant, uninterruptedsound.> The
presentïhorn is also-'obvioù’sly applioabl'e to any
installation Where an automatic intermittent
Warning is desired» If such installation does 'not
have a source of vacuum available, a'n'iotor driven
and Which lWill produce a' loud warning'fsig‘nal.
vacuum pump., lor lthe like, may be included 'in or
A'-further object is'to'provide‘a horn of the type
described 'having' associated 'therewith a’ simple
Connected YWith- the device;
and ' inexpensive `mechanism vfor' automatically
producing periodic or intermittent operation’ of
the h'orn.
With these and other objects 'in View, the'in
vent-ion resides in‘ the' construction and arrange
ment 'of l'parts shov'v'n'in the accompanying draw;
I
The nom itse1f_.comprises,ím general, a'pair
of circular, mating housing parts II and`l2 s'e'
cnred together by marginal screws I3 which 'also
serve to clamp` a diaphragm lit> and"gasketv I5
between the parte. The housing parts II an'd‘fiZ
thereby. forni air chambers IG'a-nd I'I on opposite
sides of" the diaphragm. The 'iil’i'ëítïifllaei"'> IÈ "Con-4
ings' illustrating a preferred' embodiment ‘ of ' the
tains air under atmospheric pressure atïall' times
invention.
FigureA 1 is ato-p plan Viewv of a' vacuui'n‘hor'n'
embodying the Vprinciples 'of the present inven
but is protectívely covered by4 a removable inspec
tion plate I8 ~whichneed not make an air tight
connectionwith the housing 'part I I.' Coi’iirnu’nil
calling' With the veha??ber' IT iS a lVacuufn’lin'e"I9
tion,A
-
.Figure -2”'is a viewtakenA onv the' line 2i-2bf
Figure l, showing the horn' in rear elevation', and
‘y Figure -~3 is yan enlargedy longitudinal 'sectional
view;
Figuree‘is a ldiagram showing the connections
between the different components of the 'assem
bly.
The present horn’ isv a' Warning device of gen
eral 'application that ‘is" intended prii'narilyv for
use' onvehicles such as straddle trucks in lum
ber yards. These‘truck’s' constitute a particu#
larlyserious hazard to workmen' handling lumber
because the Adriver of the truck is'perch'ed high
conti‘ölledïby a valve plunger 2li in a Valve 2|.'
The ‘valve 2i' 'is in Vturn connected'with a fitting
272" establish-ing Communication With a branchï
pipe 2Í3v`ar`1d a li?'e 24 leading to an eri'gìne'íntakë
manifold >o'r other source` of vacuum. A' valve
25'in this ’line is mounted in the truck'cab for" the
use @fine driver.
~
`
V
The housing part' l2 carries a horn tube l`3Il^`in
axial alignrnent`~vvith an annular`re'cess 3l and
the margin ofthe opening 32 is a raised anni1la'rî_`
face 33 adapted'toseat'a reciprocatin'g'disc 34,'
The'di'sc'sliiis‘ fixed @nene end of 'a spindle 35‘
ings is obstructed by the’load carried under the
screwed into a diaphragm bushingk 36 mounted
on >the'diaphragm i4; andV a nut 31 'on the bu‘s'h‘-4
can thereby turn the valvev so that the horn'will
continue to operate while the truck is in use.
sure "on both‘sid‘es of the diaphragm, so' as'to
in the air Wherehis view of immediate'surround
ing clamps th'eldiaphragrh ti'gl'itlil between" a'
truck. For the safety' of the kother Workmen it
spacer‘SS 'anda' gasket ‘39 bearing 'against an' enr
has been found' necessary to' provide such trucks
lar'g'ed head Mlîon the'bushing; The disc 34 may"
with' a Warning device which operates automati
cally When the-truck' is in use. The present `horn 40 be adjusted' longitudinally with' respect tothe'
face'33'by means'of'a screwdriver slot 4I inthe
is operated entirely by a vacuum line connected
spindle' 35; such adjustment'being maintained by
with the intake Vmanifold of the engine of the
means of lock'nut 42.' The disc 34': is preferably’
truck and is provided with» anion` and off valve
adîusted'to' have a light contact'with the face
in the cab of the truck. The operator of the truck
Associated with the horn on a common mount
ing bracket is a vacuum motor connected with
the horn vacuum line andarranged to open and
close a' valve periodically'connecting the vacuum
line> With'` the horn. By means of this unitary
mechanism,` an intermittent signal is produced
in' which the sounding'iintervals ~may be varied
33 vwhen 'the system'is open to' atmosphericv presi
allow` for vibration in both directions from a mid
position.
When`~ atmospheric' pressure exists
n
_
the
chambers iß'and I'I, the parts 'assume vthe-posi"
tion‘shown 'in Figure 3. When the valves 2 I `'and
25'are opened', the pressure is reduced in chamber
I'I causingtl'ie diaphragm I4 and the disc'34 to
rn'ove'to the'ri'ght 'under the force of atmospheric
byfad'justing the'spe'ed of the' motor. Thus the
horn mayautomatically'be blown 'at sufñcientl‘y 55 pressure 'in 'chamber >I 6. Upon' a slight movement
‘2,498,256
4
of the disc 34 to the right, air will enter the
that the pneumatic motor 47 operates under at
chamber I1 through the opening 32 faster than
mospheric pressure, exhausting through the
it can leave by way of the pipes I3 and 24 and
pipes 23 and 24 into the engine intake manifold
the pressure in chamber I1 will rapidly build up,
in the manner of the ordinary windshield wiper
returning the diaphragm and the disc 34 to their 5 motor.
original positions shown in Figure 3. The rapid
Various changes in the construction and ar
repetition of this cycle produces a musical note
rangement of parts will occur to persons skilled
in the horn 3D.
in the art, and all such modifications are in
A bracket 45 is provided for mounting the horn
cluded in the invention, the same being limited
and the valve 2l. The bracket 45 also carries 10 only by the scope of the appended claims.
a post 45 for mounting a pneumatic motor 41
Having now described my invention and in
to produce intermittent operation of the horn.
what manner the same may be used, What I claim
In the present embodiment the pneumatic motor
as new and desire to protect by Letters Patent is:
4'! consists of a conventional windshield Wiper
vacuum motor secured to the post 46 by means
of a clamp 48 and a screw 49. This motor is con
nected with the vacuum line 24 by means of the
pipe 23 and is provided with the usual speed con
trol valve 50 and a shut-off valve 5l. For the
present purpose the shut-olf valve El is left per 20
manently on and the speed control valve 50 is ad
justed to produce the desired frequency of sound
ing intervals.
The numeral 52 indicates the oscillating shaft
l. In an intermittent vacuum horn, a mount
ing bracket, a vacuum line connection. mounted
on said bracket, a valve mounted on said bracket
in communication with said vacuum line connec-tion, a vacuum motor producing oscillatory mo
tion mounted on said bracket, a vacuum line from
said vacuum connection to said motor, a vacuum
line from said valve for connection with said
horn, and means operated by said motor to inter
mittently open and close said valve.
of the motor 41 to which the Windshield wiper
arm would ordinarily be attached. In the pres
2. In a vacuum horn, a mounting bracket, a
valve mounted on said bracket, a vacuum line
ent arrangement, the shaft 52 carries an arm 53
clamped thereon by means of a clamp screw 54
plunger- for opening andclosing said valve, an
from said valve for connection with said horn, a
oscillating shaft vacuum motor mounted on said
and carrying a cam roller 55 mounted on a pin
56 in a roller slot in the end of the arm. Mount 30 bracket, valve means for controlling said motor,
a cam driven by said motor, and a lever pivoted
ed in the path of the cam roller 55 and bearing
on
said valve and bearing upon said plunger in
upon the valve plunger 20 is a channel shaped
the
path of said cam to constitute a cam follower
cam follower 60 pivoted at 6l to the valve hous
for operating said valve in accordance with the
movements of the cam.
ous oscillation of the cam arm 53 through an arc 35
3. In an intermittent vacuum horn, a mount
of 180° or less to depress the valve plunger 2D
ing bracket, a valve mechanism mounted on said
and sound the horn on each stroke of the cam,
ing 2|. The motor 41 thereby produces continu
the duration of each sounding interval being de
termined in part by the speed of oscillation of
the motor and in part by the position at which
the arm 53 is clamped on the motor shaft. If de
sired, the motor may be shut off at the valve 5l
when the cam is in a position to hold the valve
plunger 28 depressed, to cause the horn to emit
a continuous instead of an intermittent sound.
The valve 5I also may be closed when the cam
is raised as in Figure 3 to prevent mischievous
operation of the horn by unauthorized persons.
' Figure 4 shows the connections between the
different components of the assembly. When
valve 25 is opened, the partial vacuum condition
in the engine manifold draws a partial vacuum in
the main pipe line 24 and also in the branch line
23. When the horn valve 2| is o-pened, atmos
pheric air is drawn through horn tube 3U and
pipe I9 to vibrate the horn diaphragm in the
manner described. When shut-on valve 5l is
opened, the partial vacuum condition in line 23
is communicated to the variable speed pneumatic
bracket for controlling said horn, a variable speed
oscillating shaft vacuum motor mounted on said
bracket, means operated by said motor for pc
a.
riodically opening and closing said valve, and
valve means to vary the speed of said motor to
control the sounding interval of said horn.
4. In an intermittent vacuum horn, a valve for
controlling the sounding of said horn, a vacuum
motor for operating said valve intermittently,
means to adjust the speed of said motor to vary
the frequency of sounding intervals, an oscillat
ing arm driven by said motor and arranged to
open said valve at `each stroke thereof, and means
to adjust the position of said arm with respect
to said motor and said valve to vary the dura
tion of the sounding intervals.
5. In an intermittent vacuum horn, a valve
for controlling the sounding of said horn, a vac
uum motor having an oscillating shaft, an arm
for actuating said valve intermittently, means
for securing said arm on said motor shaft in ad
justed position to control the duration of each
sounding interval, and means to adjust the speed
motor 4'! to oscillate the cam arm 53. The valve 60 of said motor vto vary the frequency of sounding
5l is preferably a quick opening and quick clos
ing slide valve, so that it may be operated to stop
the pneumatic motor 4'! instantly to leave the
cam arm 53 in a particular position,
intervals.
HENRY N. DIMICK.
Thus the
valve plunger 2D may be held depressed so that 65
the horn 30 Will sound with a steady tone instead .
of an intermittent tone whenever the valve 25
in the cab of the truck is opened.
Valve 58 ís preferably a slow acting needle valve
to serve as a throttle or speed control valve for
the pneumatic motor 41. Thus the valve 58 pro
vides for adjustment of the frequency of the
sounding interval, which adjustment is not dis
turbedby operating either of the manual shutoff valves 25 or 5l. It is understood, of course,
REFERENCES CITED
The following references are of record in the
ñle of this patent:
Number
UNITED STATES PATENTS
Name
Date
1,046,164
1,419,435
1,786,214
.1,888,684
1,943,671
2,038,847
Fanning __________ __ Dec. 3,
Woodring ________ __ June 13,
McCune et al ______ __ Dec. 23,
Middleton ________ __ Nov. 22,
Hewitt et al _______ __ Jan. 16,
1912
1922
1930
1932
1934
Morrow __________ __ Apr. 28, 1936