Vacuum apparatus

A vacuum apparatus for surgical aspirators comprises a motor and vacuum pump on a supporting base with an evacuated chamber surrounding them to reduce noise produced by the apparatus. The apparatus preferably comprises first and second hollow housings of one or more wall members defining an enclosure surrounding the motor and pump, the wall members of said housings spaced apart to define a vacuum chamber around the motor and vacuum pump. The enclosure has an opening to surrounding atmosphere through the supporting base or through a sealed opening through the housings. The pump outlet communicates with surrounding atmosphere. A passageway connects the vacuum chamber both to the vacuum pump inlet and the exterior of the apparatus. Operation of said motor and pump is effective to withdraw air from the chamber to produce a vacuum therein supplied for use through the passageway, the vacuum is the reservoir being sufficient for use over a period of time and providing sound insulation against noise produced by the apparatus. The apparatus has pressure responsive valves for (1) preventing flow of air into the vacuum chamber when the surgical cannula is removed, (2) closing off the vacuum chamber from the surgical cannula when the vacuum is insufficient and causing the vacuum pump to work directly on the surgical cannula, and (3) shutting down the motor when the vacuum reaches a selected level.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to new and useful improvements in vacuum apparatus 
for use in surgery and more particularly to vacuum apparatus having 
reduced output of noise and a reservoir sized to provide substantially 
instantaneous response when needed during surgery. 
2. Brief Description of the Prior Art 
Surgical aspirators presently available on the market were mostly adapted 
from vacuum extractors used by OB-GYN physicians for therapeutic 
abortions. These machines were slow to build up to maximum pressure, and 
generally had low volume flow rates at maximum vacuum. In order for vacuum 
to be available, the machines had to run continuously or be cut on and 
off, the surgeon having to wait several seconds for maximum vacuum to 
build up each time it is needed. Also, all of the early machines and most 
of the present-day machines are excessively noisy so that if the machine 
is being used for an hour or longer, the noise becomes an unpleasant 
factor. 
Modern surgeons who use aspirators have a demand that the vacuum be 
continuously available for the entire surgical procedure. They want the 
machine to be able to deliver maximum vacuum as quickly as possible. The 
surgeon's cyclic need for maximum vacuum many times during the surgical 
procedure means that if there is a wait 5-10 second wait each time for the 
machine to reach maximum vacuum, the sum of all of the 5-10 second waiting 
periods can add up to a significant amount of time the patient is exposed 
to anesthesia. 
Additionally, if the machine's flow rate at the maximum vacuum isn't high 
enough, the surgeon has to proceed with the surgery more slowly, again 
exposing the patient to longer periods of anesthesia. 
The surgeon's need for the instant availability of maximum vacuum means the 
nurse or surgeon must manually cut the machine off and on, or the machine 
must run continuously, giving rise to noise pollution. 
Most manufacturers of modern aspirators have tried to handle the surgeon's 
need for a high flow rate and rapid rise to maximum vacuum by placing two 
motors and two vacuum pumps into each machine and/or placing larger, more 
powerful motors and vacuum pumps in the aspirator. 
A number of patents have dealt with the problems of noise abatement and 
reservoir size and utilization. 
Guarniery U.S. Pat. No. 1,380,473 discloses a suction pump for player 
pianos having surrounding sound deadening material. 
Vose U.S. Pat. No. 2,290,259 discloses a hair dryer with sound deadening 
material surrounding the fan motor. 
Crago U.S. Pat. No. 4,264,282 discloses an air compressor pump having 
surrounding sound deadening material. 
Wang et al. U.S. Pat. No. 4,395,258 discloses surgical vacuum apparatus 
with an accumulator and various control features. 
Mayoral U.S. Pat. No. 4,676,779 discloses surgical vacuum apparatus with 
various control features. 
Kayser U.S. Pat. No. 4,3I5,506 discloses surgical vacuum apparatus for 
aspirating fluids from body cavities. 
The prior art in general, and the cited patents in particular, does not 
disclose an apparatus with the control features provided by this invention 
or the complete sound deadening provided by utilizing the vacuum chamber 
as a sound insulator. 
SUMMARY OF THE INVENTION 
One of the objects of this invention is to provide a new and improved 
surgical vacuum apparatus having a vacuum accumulator with controls for 
improving the application of vacuum to the surgical site. 
Another object of the invention is to provide a new and improved surgical 
vacuum apparatus having a vacuum accumulator with controls applying vacuum 
directly to the surgical site when the vacuum in the accumulator is 
insufficient. 
Another object of the invention is to provide a new and improved surgical 
vacuum apparatus having a vacuum accumulator with controls shutting off 
the vacuum pump when the vacuum in the accumulator reaches a selected 
level. 
Still another object of the invention is to provide a new and improved 
surgical vacuum apparatus having a vacuum accumulator with controls 
preventing air flow into the accumulator when the apparatus is shut down. 
Still another object of the invention is to provide a new and improved 
surgical vacuum apparatus having a vacuum accumulator which surrounds the 
motor and vacuum pump to provide sound insulation. 
Other objects of the invention will become apparent from time to time 
throughout the specification and claims as hereinafter related. 
The foregoing objects and other objects of the invention are accomplished 
by a vacuum apparatus for surgical aspirators which comprises a motor and 
vacuum pump on a supporting base with an evacuated chamber surrounding 
them to reduce noise produced by the apparatus. 
The apparatus preferably comprises first and second hollow housings of one 
or more wall members defining an enclosure surrounding the motor and pump, 
the wall members of said housings spaced apart to define a vacuum chamber 
around the motor and vacuum pump. 
The enclosure has an opening to surrounding atmosphere through the 
supporting base or through a sealed opening through the housings. The pump 
outlet communicates with surrounding atmosphere. A passageway connects the 
vacuum chamber both to the vacuum pump inlet and the exterior of the 
apparatus. 
Operation of said motor and pump is effective to withdraw air from the 
chamber to produce a vacuum therein supplied for use through the 
passageway, the vacuum in the reservoir being sufficient for use over a 
period of time and providing sound insulation against noise produced by 
the apparatus. 
The apparatus has pressure responsive valves for (1) preventing flow of air 
into the vacuum chamber when the surgical cannula is removed, (2) closing 
off the vacuum chamber from the surgical cannula when the vacuum is 
insufficient and causing the vacuum pump to work directly on the surgical 
cannula, and (3) shutting down the motor when the vacuum reaches a 
selected level.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to the drawings by numerals of reference, there is shown in FIG. 
1 a surgical vacuum apparatus 10 illustrating a preferred embodiment of 
the invention. 
Vacuum apparatus 10 has a supporting base 11 on which there are supported a 
vacuum pump 12 and motor 13 for driving the vacuum pump. Motor 13 is 
connected to electric leads 14 to a power source 15. A fan 16 is 
positioned to circulate air for cooling vacuum pump 12 and motor 13. 
A vacuum accumulator or reservoir 17 covers vacuum pump 12, motor 13 and 
fan 16 to provide sound insulation for the apparatus as described below. 
Reservoir 17 comprises an inner housing 18 and outer housing 19 of cubic 
construction. The space between housings 18 and 19 defines a reservoir 
chamber 20 closed and sealed by a bottom wall 21. Reservoir 17 is holloW, 
i.e. forms an enclosure, with a bottom opening 22 allowing it to be fitted 
over the base 11 enclosing the vacuum pump 12, motor and fan 16 on all 
sides. 
Reservoir 17 preferably has a plurality of spacer members 23 between the 
housings 18 and 19 to support the walls thereof against collapse when 
reservoir chamber 20 is evacuated. If the walls of housings 18 and 19 are 
sufficiently strong, spacer members 23 may be eliminated. 
The pump 12 has an inlet 24 connected to vacuum reservoir chamber and an 
outlet 25 open to the space or enclosure surrounding vacuum pump 12 and 
motor 13 and communicating with surrounding atmosphere. In the 
embodiments, viz., FIGS. 1-7, where the bottom of reservoir 17 is open, as 
at 22, air discharged by vacuum pump 12 leaks to atmosphere through the 
bottom opening. In embodiments, such as FIGS. 8 and 9, where the vacuum 
pump and motor are completely enclosed, the pump outlet in connected to a 
conduit (not shown) extending through and sealed in the walls of the inner 
and outer housings to discharge to atmosphere. 
Pump inlet 24 is connected by conduit 26 to one side of a check valve 27, 
the other side of which is connected by conduit 28 to the stem of a tee 
29. One side of tee 29 is connected to the outlet 30 from a solenoid valve 
31 which has its inlet connected by conduit 32 opening into vacuum 
reservoir chamber 20. 
Solenoid valve has its coil connected by electric leads to connections 33 
and 34 on a pressure regulating switch 35. Leads 36 and 37 connect switch 
35 in circuit with motor leads 14. An electric lead 38 bypasses switch 35 
and is connected to normally closed switch 39 which is opened by manual or 
pedal action. 
Pressure regulating switch 35 may be a double switch, or a group of 
switches, which is connected to respond to pressure in vacuum chamber 20 
and has contacts controlling motor 13 and solenoid valve 31. Pressure 
responsive means for operating the switch contacts may be of any 
conventional type, including bellows, diaphragm, Bourdon tube, etc., and 
is settable to operate at a selected pressure. The pressure responsive 
means may operate against a spring having an operator to vary the spring 
force and thus select the pressure of operation of the switch. One set of 
switch contacts are operated at a pressure selected by the operator to 
shut off motor 13 at a selected low pressure (high vacuum). Another set of 
switch contacts are operated at a pressure selected by the operator to 
close the normally open solenoid valve 31 at a selected higher pressure 
(low vacuum). 
The other side of tee 29 is connected by conduit to a sealed connection 41 
through vacuum chamber 20. Sealed connection 41 may be made through a hole 
in one of the spacer members 23 or a section of the conduit may be sealed 
in the walls of housings 18 and 19. Sealed connection 41 is connected by 
conduit 42 to one side of a solenoid valve 43, the other side of which is 
connected to a receptacle 44 for the conduit or tubing from a surgical 
cannula (not shown). Gauges 45 and 46 are positioned to register the 
pressure (vacuum) in vacuum chamber 20 and in line 42 to the surgical 
cannula, respectively. Solenoid valve 43 has electrical connections 47 and 
48 to one side of a pressure regulating switch 49, the other side of which 
is connected to the power source. Leads 50 and 51 are connected to a 
normally open, manual or pedal switch 52 which bypasses pressure 
regulating switch 49. 
Pressure regulating switch 49 may be a single switch, or a group of 
switches, which is connected to respond to pressure in vacuum line 42 
leading to the surgical cannula and has contacts controlling solenoid 
valve 43. Pressure responsive means for operating the switch contacts may 
be of any conventional type, including bellows, diaphragm, Bourdon tube, 
etc., and is settable to operate at a selected pressure. The pressure 
responsive means may operate against a spring having an operator to vary 
the spring force and thus select the pressure of operation of the switch. 
The switch contacts are operated at a pressure selected by the operator to 
close the open solenoid valve 43 in response to higher pressure 
(atmospheric pressure) encountered at the receptacle 44 for the surgical 
cannula when the cannula is removed at the end of surgery. 
Reservoir 17 may be of any suitable shape so long as it is hollow to fit 
over the base 11 enclosing the vacuum pump 12, motor and fan 16 on all 
sides. A variety of shapes are shown in the isometric views shown in FIGS. 
3-7. In these embodiments, there is essentially no change in the location 
of the pump 12 and motor 13 and the connections thereto, since the only 
change is in the shape of the housings providing the vacuum chamber 20 
surrounding the pump and motor. 
In FIG. 3, reservoir 17 is formed by a housing 18 of cubic shape within a 
housing 19 of cubic shape with end wall 21 closing the reservoir chamber 
20. In FIG. 4, reservoir 17a is formed by a housing 18a of cylindrical 
shape within a housing 19a of cylindrical shape with end wall 21a closing 
the reservoir chamber 20a. 
In FIG. 5, reservoir 17b is formed by a housing 18b shape with end wall 21b 
closing the reservoir chamber of frusto-conical shape within a housing 19b 
of frusto-conical 20b. In FIG. 6, reservoir 17c is formed by a housing 18c 
having the shape of a truncated pyramid within a housing 19c of like Shape 
with end wall 21c closing the reservoir chamber 20c. In FIG. 7, reservoir 
17d is formed by a housing 18d of hemispherical shape within a housing 19d 
of hemispherical shape with end wall 21d closing the reservoir chamber 
20d. 
Alternate embodiments of the vacuum reservoir for the apparatus are shown 
in FIGS. 8 and 9. The embodiment shown in FIG. 8 comprises a vacuum 
reservoir 117 formed by inner housing 118, which is a completely closed 
cube, positioned inside outer housing 119, which is a completely closed 
cube. The bottom wall of housing 118 is spaced from and supported on the 
bottom wall 121 of outer housing 119 by spacer members 123 so that the 
vacuum reservoir chamber 120 surrounds the motor and pump on all sides and 
top and bottom. In this embodiment, the bottom wall of inner housing 118 
performs the function of supporting base 11 in supporting the vacuum pump 
and motor. 
The embodiment shown in FIG. 9 comprises a vacuum reservoir 217 formed by 
inner, closed, spherical housing 218 positioned inside outer, closed, 
spherical housing 219. The wall of spherical housing 218 is spaced from 
and supported on the wall of outer spherical housing 219 by spacer members 
223 so that the vacuum reservoir chamber 220 surrounds the motor and pump 
on all sides and top and bottom. In this embodiment, the bottom wall 
portion of inner spherical housing 118 performs the function of supporting 
base 11 in supporting the vacuum pump and motor. 
In the embodiments of FIGS. 8 and 9, there are minor, obvious changes 
required in the location of the pump 12 and motor 13 and the connections 
thereto, since the housings providing the vacuum chamber 120 or 220 
surround the pump and motor on all sides, including top and bottom. 
Consequently, all connections which were made through the open bottom of 
vacuum reservoir 17 or through or along supporting base 11, must be made 
through sealed openings in the outer and inner housings which form the 
vacuum reservoir. 
0PERATI0N 
The operation of the apparatus should be fairly apparent from the 
structural description, above, but will be described below in more detail. 
As previously noted, the use of a vacuum reservoir chamber shaped to 
enclose the motor and vacuum pump provides a highly efficient sound 
insulation for the apparatus. The controls provide for a variety of 
manually controlled and automatically controlled features of operation. 
Thus, the reservoir is a vacuum accumulator which provides a source of 
vacuum sufficient for about one or two minutes, depending on size. 
In one prototype, reservoir 20 was a 2" thick chamber around the inner wall 
that covered the motors, pumps and ventilating fans, a space of about 1.25 
cu.ft. Since most aspirators will pump between 0.3 and 0.7 cu.ft. or air 
per minute at 27" of mercury vacuum, the apparatus provides over 60 
seconds head-start compared to other aspirators. Additionally, since the 
vacuum chamber is the 2" thick area on all sides of the motor chamber 
(except the bottom), and since no sound is transmitted through a vacuum, 
excellent sound-insulation is provided. 
On start-up of the apparatus, solenoid valve 31 is open connecting vacuum 
pump 12 to vacuum chamber 20. The vacuum reservoir is likely to be at 
atmospheric pressure unless there is some residual vacuum from a previous 
operation. Solenoid valve 43 is closed preventing application of vacuum at 
the surgical cannula receptor 44. When the vacuum pump 12 is started up, 
air is drawn from vacuum reservoir chamber 20 and the vacuum line up to 
solenoid valve 43. 
After an appreciable draw-down of pressure in reservoir chamber 20, the 
operator sets pressure regulating switch 35 to a selected high vacuum (low 
pressure) for the contacts controling pump motor 13, and a selected lower 
vacuum (higher pressure) for the contacts controling solenoid valve 31. 
After the vacuum is drawn down to the point where pressure regulator switch 
shuts down motor 13, the operator (surgeon or his assistant) connects the 
surgical cannula to receptor 44. Since solenoid valve 43 is closed, it is 
necessary to operate manual or pedal switch 52 to bypass pressure 
regulator switch 49. This opens valve 43 to allow vacuum to draw air from 
the surgical cannula to keep the surgical site clear. At this point, the 
vacuum in line 42 is exposed to pressure regulator switch to open solenoid 
valve 43 and hold it open during continued operation. 
As the pressure drops in vacuum chamber 20, pressure regulator switch first 
closes the contacts starting motor 13 and then closes the contacts 
controling solenoid valve 30 to close it and cause vacuum pump 12 to work 
directly on drawing air (creating vacuum) from lines 40 and 42 leading to 
the surgical cannula. 
When the operation is completed, the surgeon (or his assistant) removes the 
cannula from connector 44. Air, at atmospheric pressure, then enters line 
42. This pressure acts on pressure regulator switch 49 to close solenoid 
valve 43 to prevent air from entering the apparatus and destroying the 
vacuum. In this condition, check valve 27 prevents air from entering the 
vacuum chamber 20 through pump 12. 
The arrangement of valves and control switches used herein allows the pump 
to run less than 50% (and possibly less than 25%) of the time its is 
required to run if there is no vacuum reservoir or electronic controls, 
thus diminishing the amount of noise pollution. The vacuum in chamber 20 
surrounding the motor, pump and fan further reduces the amount of noise. 
While this invention has been described fully and completely, with special 
emphasis on the preferred embodiments, it should be understood that, 
within the scope of the appended claims, the invention may be practiced 
otherwise than as specifically described herein.