Syringe needle abstract
A method and apparatus are disclosed for destroying syringe needles.
The apparatus has an incinerator into which a syringe needle may
be inserted, crimped by a crimper 30 burned by passing an electric
current through the needle between the needle tip and a sealing
crimp formed by the crimper 30 and the burned needle severed by
a cutter 36.
Syringe needle claims
1. A syringe needle destruction apparatus comprising a housing
having an orifice through which a syringe needle may be inserted
into the housing, crimping means mounted within said housing adjacent
said orifice for crimping a syringe needle to substantially seal
the syringe, a needle tip contact element mounted for movement along
a needle path of travel within said housing in engagement with the
needle tip, and means for establishing a voltage across said crimping
means and said needle tip contact element sufficient to burn that
portion of the needle that extends between the needle crimp and
2. The syringe needle destruction apparatus of claim 1 wherein
said needle tip contact element is mounted for movement by mounting
means that comprises a track mounted within said housing extending
substantially parallel to the needle path of travel, and a carriage
movably mounted upon said track and spring biased towards said orifice
to which carriage said needle tip contact element is mounted.
3. The syringe needle destruction apparatus of claim 1 wherein
said crimping means comprises a pair of plates and motor means coupled
to at least one of said plates for imparting relative movement of
the crimping plates towards each other.
4. The syringe needle destruction apparatus of claim 1 further
comprising cutting means mounted within said housing adjacent said
crimping means for severing a burned portion of the needle from
a substantially unburned portion.
5. The syringe needle destruction apparatus of claim 4 wherein
said cutting means comprises a shearing plate mounted in sliding
contact with said crimper means.
6. The syringe needle destruction apparatus of claim 1 further
comprising a germicidal ultraviolet light generating means mounted
within said housing.
7. A method of destroying at least a portion of a needle needle
that extends outwardly from the barrel and hub of a syringe to a
needle tip, and with the method comprising the steps of:
(a) inserting the needle portion into an incinerator while leaving
the barrel outside of the incinerator;
(b) forming a sealing crimp in the hollow needle adjacent the syringe
(c) burning the needle by passing an electric current through the
needle between the needle crimp and tip.
8. The method of claim 7 further comprising the steps of:
(d) severing the burned portion of the needle adjacent the crimp.
9. The method of claim 8 wherein the crimping, burning and severing
steps are preformed in sequence.
10. The method of claim 8 wherein the needle is irradiated with
ultraviolet light within the incinerator housing.
11. A syringe needle destruction apparatus comprising;
means for receiving and containing an exposed needle portion of
means for forming a crimp in the needle distally from the needle
means for passing an electric current through said exposed needle
12. The syringe needle destruction apparatus of claim 11 further
comprising means for severing the exposed needle portion adjacent
13. The syringe needle destruction apparatus of claim 12 further
comprising control means for controlling said needle crimping means,
said electric current passage means and said needle severing means
in a sequence of operations.
14. A syringe needle destruction apparatus comprising a main housing
and an incinerator housing detachably mounted to said main housing,
said incinerator housing having an orifice, a track mounted in said
incinerator housing, a carriage movable mounted on said track and
spring biased toward said orifice, crimping means mounted within
said incinerator housing for forming a crimp in a syringe needle
inserted into said incinerator housing through said orifice, means
for establishing a voltage across at least a portion of a syringe
needle within said incinerator housing which includes an electrode
mounted on said carriage facing said orifice, and severing means
mounted in said incinerator housing for severing at least a portion
of a needle inserted into said incinerator housing between a crimp
formed in the needle by said crimping means and the needle tip.
Syringe needle descriptionTECHNICAL FIELD
This invention relates to methods and apparatuses for destroying
BACKGROUND OF THE INVENTION
Disposable hypodermic syringes are widely used in hospitals and
other medical facilities to draw body fluids from and to inject
medications into patients. These syringes are made disposable because
of the difficulties and inefficiencies involved in re-sterilizing
syringes for reuse. Because the syringes are intended to be disposed
of after use, a problem arises as to their safe post-use storage
and disposal and in preventing them from being recklessly reused
by others. By law syringes may not be disposed of as ordinary waste
since their sharp needle tips, as well as disease causing organisms
sometimes carried by them, may injure hospital and waste disposal
To dispose of syringes safely, devices have been devised that mechanically
sever the syringe needles from their barrels. These are exemplified
by those shown in U.S. Pat. Nos. 4255996 4445644 and 4969379.
Though these devices do prevent reuse of syringes, a sharp needle
stub remains intact and hazardous. Other types of syringe destruction
devices grind the syringes into small pieces as shown in U.S. Pat.
No. 4905916. These however do not provide for sanitary syringe
residue disposal. Furthermore, their shearing action tends to release
fluid contaminates to ambience.
Incinerators have also been used to destroy syringes is a sanitary
manner. Bulk incineration of accumulated syringes however poses
the threat of injury still occurring during accumulation and incineration
input. Thus, portable devices have been used which can incinerate
the needles by passing an electric current through them. This approach
is described in U.S. Pat. No. 4877934 and 4965426. These devices
however leave the barrel portion of the syringe with an opening
at one end through which contaminates may emerge to ambience. Furthermore,
some pathogens contained within the needle and expelled from the
syringe during insertion are not killed by the incineration process.
It thus is seen that a need remains for a method and apparatus
for destroying syringe needles in a more effective and efficient
manner. It is to the provision of such that the present invention
is primarily directed.
SUMMARY OF THE INVENTION
In a preferred form of the invention, a syringe needle destruction
apparatus comprises a housing having an orifice through which a
syringe needle may be inserted into the housing. Crimping means
are mounted within the housing adjacent the orifice for crimping
a syringe needle to substantially seal the syringe. A needle tip
contact element is mounted for movement along a needle path of travel
within the housing in engagement with the needle tip. The apparatus
also has means for establishing a voltage across the crimping means
and the needle tip contact element sufficient to burn that portion
of the needle that extends between the needle crimp and tip.
In another preferred form of the invention, a method provides for
destroying a portion of a hollow needle that extends outwardly from
the barrel and hub of a syringe to a needle tip. The method comprises
the steps of inserting the needle portion into an incinerator while
leaving the barrel outside of the incinerator, forming a sealing
crimp in the hollow needle, and burning the needle by passing an
electric current through the needle between the needle crimp and
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a perspective view of a syringe needle destruction apparatus
that embodies principles of the invention is a preferred form.
FIG. 2 is a perspective view of internal components of the apparatus
of FIG. shown with the housing and a portion of the electric wiring
removed for clarity.
FIG. 3 is a block diagram of the apparatus of FIG. 1.
FIG. 4 is a flow diagram of the operation of the apparatus of FIG.
1 and method of the invention.
FIGS. 5A-5F are a sequence of views, shown in crosssection, of
a portion of the apparatus of FIG. 1 showing a syringe needle being
inserted, crimped, incinerated and severed in accordance with a
method of the invention.
With reference next to the drawings, there is shown an apparatus
-0 having a housing 11 The housing 11 has an upper, self-contained
unit 12 for syringe needle destruction operations that is mounted
atop a lower, self-contained unit 13 in which residual syringe barrels
may be collected and stored. The upper unit is shown in FIG. 2 as
having a main power supply housing 15 to which an incinerator housing
16 is removably mounted. The incinerator housing 16 has a conically
shaped needle receiving orifice guide 17 mounted about a central
orifice. An annular activation switch, shown generally at 18 is
mounted about the orifice guide 17 to the front of the housing 16.
The activation switch 18 is coupled by means of conductors 21 with
a controller 22 mounted within the housing 15.
A track 19 is mounted within the housing above the orifice guide
17. A spring biased carriage 20 is movably supported for travel
upon the track 19. The carriage 20 bears an electrode 23 with a
concave face that faces and is aligned with the needle orifice.
The carriage 20 has four wheels 24 rollably positioned upon the
track 19 and a coil spring 25 having one end mounted to the track
so as to bias the carriage towards the needle orifice. A flexible
conductor 26 connects the carriage electrode 23 to a transformer
55 in all positions of the carriage along the track.
A needle crimping means 30 is mounted in housing 16 closely adjacent
to the needle orifice. The crimping means comprises an upper crimping
plate 31 pivotably mounted on a pivot pin 34 above the orifice and
a stationary lower crimping plate 32 rigidly mounted below the needle
orifice. The lower plate 32 also functions as an electrode. A conductor
33 couples the lower plate 32 with the transformer 55.
The apparatus also has means for severing needles that includes
a pivotable cutting blade or shearing plate 36 pivotable mounted
on a pivot pin 34 in sliding contact with the rear side of the upper
crimping plate 31. Both the upper crimping plate 31 and the blade
36 extend through aligned openings in two adjacent walls of the
housing units 15 and 16 so that one of their end portions is within
the confines of the main power supply housing 15. An electric motor
40 mounted in the main power supply housing 15 has its power output
drive shaft coupled with both a crimping cam 38 and a cutting cam
39. The motor is electrically coupled to the controller 22 by means
of control line 37 as shown in FIG. 3. An ultraviolet light 41
mounted in the incinerator housing 16 is also coupled with the
controller by a conductor 42. A system ready LED type indicator
lamp 48 a trouble/burn process LED type indicator lamp 49 and
a full status LED type indicator lamp 50 are all mounted to the
front of the incinerator housing 15. Each is connected to the controller
22 via a line or cable 51 of ganged conductors.
As shown best in FIG. 3 transformer 55 is coupled to the controller
22 by a conductor 56. A high temperature sensor is mounted on the
transformer 55 coupled with the controller by conductor 58. The
carriage electrode 23 and the lower crimping plate/electrode 32
are coupled with the transformer by means of conductors 26 and 33
A photoelectric burn done sensor is also mounted within the incinerator
unit 16. This sensor is mounted so that the carriage 20 interrupts
its beam when the carriage is at a position closely adjacent the
orifice. An unshown motor home sensor is mounted adjacent the motor
40 to indicate that the cams have completed a full cycle so as to
have returned to their initial, apparatus-ready positions prior
to apparatus activation.
Finally, the housing lower portion 13 has a door 65 that is provided
with a slot 66 located on its top edge. A removable bin 67 is located
within the housing lower portion 13 which has a contoured chute
68 sized to extend through the door slot 66 when the door is closed.
Operation of the apparatus may best by understood by reference
to FIGS. 5A-5F. In FIG. 5A a conventional syringe S having a barrel
B, a plastic needle hub H, and a metallic, needle N is guided by
an operator, such as a nurse, nurse's aid, or hospital attendant,
into the needle receiving orifice. The conical shape of the orifice
guide 17 serves to guide the needle tip into and through the orifice.
As the needle N is pushed into the incinerator housing 16 it passes
between the crimping plates 31 and 32 bringing its tip into contact
with the carriage electrode 23. As the needle is pushed further
into the unit it drives the carriage 20 away from orifice along
track 19 against the bias provided by spring 25 as shown in FIG.
5B, until either the syringe hub H abuts the conical orifice guide,
as shown in FIG. 5C, or until the carriage has traveled the maximum
distance allowed by the track 19 by engaging an unshown carriage
stop. Carriage movement is limited to insure that an operator does
not attempt to incinerate the entire length of an extraordinarily
long needle in a single operations and thereby exceed power capacity
limits. Such long needles are instead incinerated in a succession
of operations as such operations are herein described.
Once the syringe is fully inserted into the incinerator, as shown
in FIG. 5C, the operator depresses the activation switch 18 as with
his or her finger while holding the syringe barrel. In response
to this the controller 22 which is of conventional construction
that preferably employs a microprocessor chip, energizes the motor
40 and the trouble/burn process lamp 49 and deenergizes the system
ready lamp 48. The motor then commences to rotate the crimping cam
38 and the cutting cam 39. The crimping cam 38 engages and pivots
the upper crimping plate 31 about pivot pin 34 thereby crimping
needle N between the upper crimping plate 31 and the lower crimping
plate 32 as shown in FIG. 5C. The crimping of the needle serves
the dual function of sealing the syringe needle residual stub and
providing an electric contact with the needle at the crimp site
since the lower plate 32 also functions as an electrode.
With the needle crimp still held firmly by the plates 31 and 32
the controller next energizes the electrodes 23 and 32 by coupling
them with the transformer 55 and its 7 volt A.C. voltage. For the
electrical resistance provided by a 16 gauge stainless steel needle
portion of a length approximately three an one half inches between
the electrodes 23 and 32 approximately 40 amps is caused to flow
through it causing the needle portion to burn and char throughout
in less than a second. This general voltage level is preferred as
substantially higher voltage levels can cause sparking and welding
of the needle to the electrodes and substantially lower voltages
can lead to insufficient or too slow incineration.
During the brief period of incineration, the spring 25 continuously
urges the two electrodes towards one another. This serves to maintain
them in good contact with the needle and also to create a compaction
force on the needle char to lengthen the time that the charring
needle provides a conductive path between the electrodes. As incineration
progresses and the needle weakens, it becomes unable to hold the
electrodes apart. As a result, the carriage and electrode 23 then
advance towards the crimping means, as shown in FIG. 5D. This causes
the needle to fold and twist which usually forms it into a compact,
single extension needle residue char of a coil-like shape that usually
remains attached to the unburned portion of the needle at its crimp.
Upon return of the carriage to its initial position adjacent the
crimping means 30 the carriage interrupts the photoelectric burn
done sensor beam which indicates to the controller that the burn
process is complete. The controller then de-energizes the electrodes.
If the burn done sensor beam has not been interrupted after expiration
of a two second time period from burn initiation, the controller
de-energizing the electrodes anyway. It is at approximately this
time that the cutting cam 39 has rotated to a position forcing the
cutting blade 36 downward through the needle char closely adjacent
the crimp. The cutting blade severs the residue char whereupon it
free falls, as shown in FIG. 5E, to the bottom of the incinerator.
With the crimping plates once again separated, the needle crimp
is released enabling the operator to remove the syringe and its
short, sealed, needle stub from the incinerator unit and place it
in the lower storage unit. Once the cams have fully returned to
their initial positions a motor home or cycle complete sensor inputs
a signal to the controller 22 which de-energizes the motor 40 re-energizes
the system ready lamp 48 and de-energizes the trouble/burn process
49 to indicate that the apparatus is reset and ready to incinerate
Though most pathogens within the needle are killed by its incineration,
some heat resistent ones may not be. Also, some pathogens may be
expelled during insertion and operation of the needle into the apparatus.
For these reasons the incinerator is also provided with a germicidal
ultraviolet light 41 which is energized by the controller for a
short time following needle severance to kill such remaining pathogens.
Once the fill sensor lamp indicates that the incinerator housing
16 is filled to capacity, it may by removed for disposal. Alternatively,
the incinerator housing may have a disposable collecting bin removably
mounted within the incinerating housing 16.
From the foregoing, it is seen that a method and apparatus for
destroying syringe needles is now provided which overcomes problems
associated with those of the prior art. It should however be understood
that the just described embodiment merely illustrates principles
of the invention in a preferred form. Many modifications, additions
and deletions may, of course, be made thereto without departure
from the spirit and scope of the invention as set forth in the following