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Publication numberUS3891381 A
Publication typeGrant
Publication dateJun 24, 1975
Filing dateMar 28, 1974
Priority dateMar 31, 1973
Also published asDE2415431A1
Publication numberUS 3891381 A, US 3891381A, US-A-3891381, US3891381 A, US3891381A
InventorsMoriya Nobuyoshi
Original AssigneeMansei Kogyo Kk
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Spark ignitable cigarette lighter
US 3891381 A
Abstract
A spark ignitable cigarette lighter having a burner disposed within a first chamber in gaseous communication with the exterior through a surrounding second chamber and wherein the communicating passages are offset to diffuse and direct an inward flow of combustion supporting air in such manner as to assure safe and stable ignition at the spark gap. The actuator of the lighter is arranged around the burner housing so as to be displaceable in the axial direction.
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United States Patent 1 1 Moriya June 24, 1975 1 SPARK IGNITABLE CIGARETTE LIGHTER [75] Inventor:

[73] Assignee: Mansei Kogyo Kabushiki Kaishya,

Kawaguchi shi, Japan [22] Filed: Mar. 28, 1974 [21] Appl. No.: 455,866

Nobuyoshi Moriya, Urawa, Japan [30] Foreign Application Priority Data Mar. 31, 1973 Japan 48-39329 3,425,783 2/1969 Gotu 431/255 3,486,075 12/1969 Steinke et a1. 431/255 X 3,826,952 7/1974 Iwasaki et a1. 431/255 X Primary ExaminerEdward G. Favors Attorney, Agent 0r FirmRobert E. Isner, Esq.

[57] ABSTRACT A spark ignitable cigarette lighter having a burner disposed within a first chamber in gaseous communication with the exterior through a surrounding second chamber and wherein the communicating passages are offset to diffuse and direct an inward flow of combustion supporting air in such manner as to assure safe and stable ignition at the spark gap. The actuator of the lighter is arranged around the burner housing so as [56] References Cited to be displaceable in the axial direction.

UNITED STATES PATENTS 2,986,027 5/1961 Lockwood 431/151 18 Claims, 7 Drawing Figures PATENTEDJIJM 24 I975 SHEET FIG. 3

' sum PATENTEDJUN 24 1975 FIG. 6

FIG. 7

FIG. 4

SPARK IGNITABLE CIGARETTE LIGHTER The present invention relates to liquefied gas fueled cigarette lighters having piezoelectrically energized electric spark ignition and particularly to an improved actuating and combustion air controlling construction for such type lighters.

Liquefied gas fueled cigarette lighters having piezoelectrically energized electric spark ignition generally have the burner nozzle or element or discharge electrodes located within the lighter casing or within a cap member to minimize if not prevent possible damage to the electrodes and/or the hazards of electric shock to the user of the lighter. Lighters of the general type noted are disclosed in US, Letters Pat. Nos. 3,399,949 and 3,408,153 and efficient operation thereof requires the proper feeding of combustion air to the locus of ig-, nition. In such type of lighter constructions, the conventional types of combustion air feeding means oper ate to often obstruct rather than to assure the desired ignition of the lighter upon depression of an actuator element inwardly of the lighter casing. For example, when actuator depression operates to cause some portion of the air within the lighter casing or within the actuator to be blown toward the locus of ignition. Such air flow, if not carefully regulated or controlled, often hinders the safe and stable ignition of fuel gas or even blows out an ignited flame. As the actuator is made larger for easy operation thereof, the more pronounced become the above noted diff culties. Moreover, in lighters of the type herein of concern, the actuator is generally located on a side of the lighter casing or in such a way that. the actuator is set off from the longitudinal or horizontal axis of the lighter. Such actuator location requires a selective positioning of the lighter by the user thereof preparatory to use, such as having a partidular side of the lighter facing the user and in partial loading on the lighter when actuated. 1

This invention may be briefly described as an improved combustion for liquefied gas fueled and piezoelectrically energized electrically ignitable lighter and which includes, in the broad aspects, a burner element, a perimetric housing for the burner having a flame opening formed in the top wall thereof and first air inlets in a peripheral wall thereof operatively associated with an internally disposed air flow control member having second air inlets positioned in the vertical sidewall thereof and disposed in offset relation with the first air inlets. The vertical sidewall of the air flow control member is adapted to deflect the air flowing through the first air inlets and provides for a diffused entry thereof into the locus of ignition to assure the conjoint result of providing an adequate feed of combustion air to the locus of ignition and to minimize, if not avoid, turbulent flow of such air in said area. Such arrangement also operates to protect the flame from being blown out by winds externally of the burner housing. In its more narrow aspects, the upper surface of the lighter is substantially constituted by the burner housing and the exposed surface of the actuator and the air inlets on the burner housing are disposed beneath the top wall of the actuator when the latter is biased in its extended or unactuated position. Under such arrangement, depression of the actuator effects a positive feeding of combustion supporting air to the locus of ignition through the air inlets on the burner housing and air flow control member. In further narrow aspects, the

subject invention includes a selective positioning of the air inlets on the burner housing to expose the same to the atmosphere when the actuator is in its depressed or actuated position so that the necessary combustion air may be supplied for the continuous burning of fuel; the mounting of the actuator in surrounding relation with the burner housing to faciliate the ready accessibility of the actuator and to equalize the operational loads on the lighter; and the provision ofmeans to prevent inadvertent operation of the actuator when the lighter is an upside down or reversed condition.

I A primary object of the present invention is the provision of an electrically ignitable lighter of above type that includes an improved combustion air feeding system to secure safe and stable fuel ignition.

Another object of the invention is to provide anelectrically ignitable lighter of the above type that includes an improved actuator assembly which effects both easy operation and a high degree of protection for the inner mechanisms thereof.

A further object of the invention is the provision of a lighter of the abovementioned type wherein the feed of combustion air is controlled by the actuator assembly. I

A futher object of the present invention is the provision of an easily operable electrically ignitable lighter, for pocket or table use of unique and neat appearance.

Other and further objects and advantages of the subject invention will be appreciated from the following portions of this specification and from the appended drawings which illustrate, in accord with the mandate of the patent statutes, a presently preferred construction for a lighter, that incorporates the principles of this invention.

Referring to the drawings:

FIG. 1 is an elevation, partly in section, showing inner mechanism of a lighter constructed according to the principles of this invention; I

FIG. 2 is a vertical section, partially broken away, of the lighter shown in FIG. 1; I

FIG. 3 is an exploded oblique view showing certain essential components of the lighter;

FIG. 4 is an oblique view of a burner assembly as incorporated in the lighter; I

FIG. 5 is an exploded oblique view of the components making up the burner assembly in FIG. 4; I

FIG. 6 is a top plan view of the lighter;

FIG. 7 is an oblique view showing the actuator stop assembly included in the lighter.

Referring initially to FIGS. 11 to 3, there is provided an external cylindrical open ended casing 1 having a frame 2 made of resinous material disposed therewithin. The frame 2 is selectively contoured to include a substantially rectangular recess adapted to contain a liquefied gas tank 3 and a second recess adapted to contain a chassis assembly mounting a piezoelectric high voltage generating device 5. As shown in FIG. 3,.

the chassis 4 assembly comprises a folded metal plate providing a pair of. opposed standing walls which are adapted to positional support the piezaelectric element 5, a hammer member control cam in the general shape of a crank 6, a strikeror hammer 7 for the piezoelectric element 5, and an operator element 8. As best shown in FIG. 1, the hammer member7 and operator element 8 are pivotally mounted on a common pin 9 supported by the standing walls of the chassis 4. The hammer 7 is biased into piezoelectric element striking position by a spring which is wound around the pin 9 with one end abutting a stop on the operating member 8 and the other end overlying the hammer 7. The hammer 7 includes a pair of projections or lugs 13 adapted to abut the upper surface of the first arm of a bifurcated hammer member control cam 6 which serves to hold the hammer 7 in the retracted position remote from the piezoelectric element unit 5. The hammer member control cam 6 is pivotally mounted around pin 1] supported by the standing walls of chassis 4 and is biased for limited movement in the clockwise direction (as seen in FIG. 1) by a cam return spring 12. The operator member 8 is provided with a transverse bar 14 which is displaced, when actuated, into engagement with the upper surface of the second arm of the cam 6 to rotate the latter in the opposite direction (i.e., counterclockwise as seen in FIG. I) so as to disengage the other arm of the cam 6 from the projections 13 on the hammer 7 and permit the energy stored in spring 10 to displace the hammer into engagement with piezoelectric element 5. As is apparent from the drawing, the bar 14 also serves to lift and rotatably displace the hammer 7 in the counterclockwise direction in the resetting cycle to return it in its initial or cocked position.

As best shown in FIG. 3, the chassis includes a pair of lateral areas 15 extending from the top of the standing walls to hold down and position the fuel tank 3 within its socket or recess within the frame 2. The chassis 4 is fixedly mounted within the central recess in the frame 2 by the transversely disposed pin 18 which extends between opposed walls of the frame 2 through the complemental apertures 15a at the ends of the arms 15 of the chassis and the apertures 15b in the walls of the frame. Mounted on the upper end of the fuel tank 3 is a spout or delivery valve 16 to control the release of combustible fuel gas therefrom, having a valve stem 17 extending upwardly therefrom and passing between the laterally extending arms 15 of the chassis 4. The extending valve stem 17 is disposed in operative engagement, as by an E-ring 57, with one end of a pivotally mounted angle iron or crank 19 whose other arm is disposed in operative sliding contact with the terminal end of the pivotally mounted operator member 8. The pivotal mounting of the crank 19 is readily provided by the disposition of the lateral extensions 21 thereon within the sockets or bosses disposed on the upper sides of the laterally extending arms 15 of the chassis 4. As will now be apparent, the plate 19 may be pivotally displaced around the bosses 20 to open and close the normally biased closed delivery valve 16 in response to the rotative movement of the operator member 8.

Mounted on the upper end of the frame 2 is a burner assembly. As best shown in FIGS. 4 and 5, such burner assembly generally comprises a selectively contoured support member 22, a burner nozzle assembly 23, an air flow control member 24 and a burner housing or cap member 25 all arranged for coaxial assembly. A pair of shank portions 36, made of electric insulating material, extend downwardly from the under side of the support member 22 and are sized to fit within a pair of vertical guide walls 58 within the central recess of the frame 2. The burner assembly 23 includes a tubular nozzle combined with a coiled wire 27 disposed therewithin and fixedly mounted into a central bore 28 on the support member 22 together with a metallic lug plate 29 which is electrically connected, through a suitable resistance element 30 to the piezoelectric element unit 5. As is now apparent. the coiled wire 27 on the nozzle end is electrically converted to the piezoelectric element 5 through said lug plate 29 and thus serves as one of the discharge electrodes. The dependent terminal end of the burner tube 23 is connected by means of an elastic end of the valve stem 17 in the delivery valve 16 for the fuel tank 3. Extending upwardly from the surface of the support member 22 are two pairs of dia metrically disposed peripheral pillars or wall segments 54 and which define for rectangularly shaped openings thereinbetween.

Mounted on the upper flat face of the support member 22 is an annular air flow control member, generally designated 24. The air flow control member 24 is of smaller diameter than the support member 22 and is sized so that the dependent vertical sidewall portion 60 thereof surrounds the burner assembly 23 with its nozzle 27 being located under the upper defining edge of the member 24 so that the latter may serve as a deflecting wall for air flow and to also partition the area within the housing 25 into two chambers. The dependent side walls of the air flow control member 24 includes two pairs of diametrically opposed notches 39 each one of which defines, in association with the upper flat face of the support member 22, an air flow opening. The notches 39 are located so as to admit air beneath the terminal end of the nozzle 27. The air flow control member 24 is suitably positioned on the surface of the member 22 by the reception of a protrusion 32 on the outer periphery of the member 24 within a complementally shaped recess 33 on the upper surface thereof.

The burner housing or cap member 25 is made of electrically conductive material and is sized to cover the upper portion of the support member 22 (including the air flow control member 24 supported therein) and to be supported by the four pillars 34 on the member 22. Included in the top wall of the burner housing 25 are four air slits 50 arranged on one circle concentric with a flame opening 56 therein (see FIG. 6). The upper marginal edge of the air flow control member 24 abuts on the top wall of the housing 25 adjacent the inner defining edges of the air slits 50 thereon. The burner housing flame opening 56 is selectively contoured to provide two pairs of diametrically opposed relatively sharp projections 35 so as to form four well defined spark gaps with the coiled" wire 27 on the burner 23.

The assemblage of above described elements comprising the burner assembly is adapted to be maintained in operative assembled relation with the chassis 4 by a U-shaped tensioned steel wire 37 whose terminal ends are engaged with a pair of bores 36 on a skirt portion of the housing 25 with the base thereof being disposed beneath the dependent lugs 26 of support member 22 and disengageable by a pair of hooks 59 on the opposed standing walls of the chassis 4 (see FIGS. 2 and 4). At the same time, the under edge of the housing 25 is pressed on the frame 2 by the tensioned wire 37. As will now be apparent, the burner assembly is thus fixedly mounted on the frame 2 so that the burner assembly 23 is located on the central longitudinal axis of the lighter. The tensioned steel wire 37 also serves to electrically connect the housing 25 to the casing for the piezoelectric element unit 5 which is grounded to chassis 4.

The peripheral wall of the housing 25 includes two pairs of diametrically opposed elliptically shaped apertures 38. The notches 39 on the member 24, the pillars 34 on the member 22 and the through bores 38 on the burner housing 25 are arranged in such a way that each notch 39 will readily face an adjacent pillar 34 with the through bores 38 disposed intermediate the pillars 34, i.e., as by an angle of 45 when the notches and pillars are spaced 90 apart. Accordingly, air flow through the bores 38 will be first directed against the solid vertical sidewall portions 60 of the air flow control member 24, and then will be deflected by said sidewall at essentially right angles to flow toward the notches and then change direction again to pass through the notches 39 with its flow velocity markedly reduced. At the same time, some portion of the entering air will escape upwardly through the air slits 50 on the top wall of the housing 25. By theaforesaid arrangement a substantially optimum condition of air flow for spark ignition will be provided around the burner nozzle 27.

Returning now to FIGS. 1, 2 and 4, a reversed cup like actuator member 40 having an axial bore 48 sized to slidably contain the burner assembly 25 and an outer dependent sleeve portion 41 sized to be contained within the casing l is provided. The actuator member is coaxially mounted around the burner assembly with the top of the burner housing 25 slightly protruding above the upper surface of the actuator 40 within the latter in its inoperative and extended position. The actuator member 40 is linearly displaceable along the burner assembly housing 25 and is normally biased in its extended position by a helical returnspring 47 disposed intermediate the frame 2 arid the underside of the actuator. A lateral rod extends between a pairof diametrically opposed points on the actuator member side wall 41. The lateral rod 42 extends through the frame 2, the chassis 4 and the operator member 8 and operatively connects the actuator member 40 to the operator member 8. The opposed sidewalls of the frame 2 and chassis 4 are formed with a pair of rectangular openings 43 and 44 to clear a path for operative travel of the rod 42 and to limit the upward movement of the rod 42 and actuator 40. The extent of downward displacement of the actuator 40 is limited by a peripheral step or shoulder 45 around the frame 2 adapted to abut the under edge of the actuator member 40. The frame 2 is desirably formed to provide liners 46 at the outer sides of the standing walls thereof to smoothly guide the actuator member 40 in its path of displacement. The defining sidewall of theaxial bore 48 of the actuator member 40 defining the central opening therein for the burner housing 25-is of such a limited length that it does not cover the through bores 38 in the burner housing member 25 in either the advanced or retracted positions thereof but rather passes thereover during the operative advancing stroke of the actuator 40 against the action of its biasing opening 47. Accordingly, upon depression of the actuator 40, air disposed within the inner recess 49 thereof is impelled to pass through the through bores 38 en route to the ignition area in the controlled flow mode as described above. As will be apparent to those skilled in this art, the actuator 40 may be arranged on the outside of the casing 1 provided that suitable openings are formed in the easing 1 to clear the rod 42. The actuator 40 also may be sized to be flush with the top burner housing 25 when the actuator is in its retracted or inoperative position.

In order to prevent undesired ignition when the lighter is in an upside down condition. as during refilling operations, means are provided to limit actuator displacement. As best shown in FIG. 7, a rotatably displaceable and greatly responsive eccentric 51 is mounted on the end of the rod 42 and disposed between the frame 2 and casing 1. The eccentric 51 is suitably formed from a plate of a substantially quartered circular disk having an extending arm 52 in the diametrical direction. The eccentric 51 is sized and rotatively mounted on the rod 42 in such a way that the same will be positioned as shown in FIG. 7, i.e., so that the end of the arm 52 rides on one of the paralleled sidewalls of the frame. 2., when the eccentric is under gravitational rotative force in the counterclockwise direction, as would normally be extant when the lighter is being used. On the bottom wall of the frame 2 there is provided an opening 53 to accommodate and clear the arm 52 when actuation of the lighter depresses the rod 42. When the lighteris reversed, as for example especially to charge the fuel tank 53 through a refill valve 54 on the bottom wall thereof, the eccentric 51 will be rotated in the clockwise direction by gravity to have the end of the arm 52 abut on the other sidewall of the frame- 2. Downward displacement of the eccentric 51 and the rod 42 is now effectively limited by the engagement of the arm 52 comer between the sidewall and the bottom wall of the frame 2. A boss 55 may be included in said corner to adjust the stop level of the actuator 40 under such condition.

In the normal operation of the described unit, when the user of the lighter pushes down on any top portion of the actuator member 40, the latter will be moved downwardly around the burner housing 25 to rotatably displace the operatormember 8 through the rod 42. Such rotative displacement of the operator 8 effects a rotative displacement of the crank 19 and an opening of the fluid delivery valve 16 to permit the combustible fuel gas to'flow via the valve stem 17 and tube 31 to the burner nozzle 27. Concurrently therewith, the rotative displacement of the operator 8 further compresses spring 10 to increase the available striking energy stored therein. The continued depression of the actua= tor 40 effects a rotation of the cam 6 by the bar l4on the operator member 8 to release the spring biased hammer 7 which strikes the piezoelectric element unit 5. The voltage generated therein is applied to the nozzle 27 and the sparks bridging to the discharge electrodes 35 on the burner housing 25 ignites the gaseous fuel flowingfrom the tank 3 through the valve' 16, connecting tube 31 and nozzle 27. Upon releasing the depressive force from the actuator 40, the latter is returned to its upper initial position by the new compressed return spring 47 whereupon the hammer 7 is positively raised to its initial position by the bar 14 on the operator member 8 which is returned by the 'rod 42 connected to the actuator 40. At the same time, the cam 14 is returned by the spring 12 to its initial position abutting the hammer 7 and the spout valve 16 is reclosed by its biasing spring.

Having thus described my invention, what I claim is:

l. A piezoelectrically energizable spark ignitable cigarette lighter comprising a casing, piezoelectric means for generating a high voltage, a striker operatively engageable with said piezoelectric means, an actuator member for effecting displacement of said striker, a pair of spaced electrodes defining a spark gap connectable to said piezoelectric voltage generating means, a fuel tank disposed within said casing, a burner assembly including a burner nozzle connected in fuel transfer relation with said fuel tank and a burner housing member disposed around said burner, said burner housing having a top wall with a flame opening therein and a peripheral wall having at least one aperture therein, and an air deflecting wall disposed in radial alignment with said aperture to shield said burner nozzle from direct flow of combustion supporting air passing through said aperture.

2. A lighter according to claim 1 wherein said deflecting wall is disposed intermediate said burner and said burner housing member and defines a first inner chamber and a second chamber disposed in surrounding relation therewith, said deflecting wall having at least one cutout portion therein, said first chamber communicating with said second chamber through said cutout portion, and through said aperture in the burner housing member externally thereof.

3. A lighter according to claim 2 wherein said burner assembly includes a support member defining a bottom wall for said two chambers and having a peripheral edge disposed in contact with the peripheral wall of said burner housing member beneath the aperture therein and wherein the upper end of said deflecting wall is disposed adjacent the inner side of the top wall of said burner housing and the lower end thereof rests an said support member.

4. A lighter according to claim 2 including at least one air slit disposed in the top wall of said burner housing member located between the peripheral wall of said housing and said deflecting wall.

5. A lighter according to claim 2, wherein said cutout portion on the deflecting wall is disposed in remote offset relation with the aperture in the peripheral wall of said burner housing member.

6. A lighter according to claim 5, wherein said cutout portion on the deflecting wall is positioned so as to face the burner portion under a nozzle thereof.

7. Alighter according to claim 6, wherein said deflecting wall is provided at the lower end thereof with a notch which is adapted to form said cut out portion together with said support member.

8. A lighter according to claim 1, wherein said burner assembly includes a burner housing member of electrically conductive material electrically connected to one pole of said piezoelectric voltage generating means, a nozzle on said burner electrically connected to the other pole in said piezoelectric voltage generating device, and at least one discharge electrode formed on a peripheral edge of said flame opening in the burner housing to form a spark gap with said nozzle.

9. A lighter according to claim 8, wherein said flame opening includes two pairs of diametrically opposed electrode portions each of which is adapted to form a spark gap with said burner nozzle.

10. A lighter according to claim 3, wherein said burner housing member, said deflecting wall and support member therein are fixedly intercoupled by a tensioned wire with a chassis member for the piezoelectric voltage generating means whereby said housing is electrically connected to said voltage generating device through said chassis member.

11. A piezoelectrically energizable spark ignitable' cigarette lighter comprising a perimetric casing, a piezoelectric high voltage generating device, a striker assembly operatively engageable with said device, a spark gap connected to said piezoelectric device, a burner assembly including a burner housing having a flame opening at a top wall thereof, a burner located in said housing, and an actuator member surrounding said burner housing and being in telescopic engagement with the casing of the lighter.

'12. A lighter according to claim 11, wherein said ac-' tuator member protrudes beyond an end of said casing and is adapted to be moved linearly along said burner housing.

13. A lighter according to claim 11, wherein said burner, burner housing, actuator and easing are coaxially disposed and wherein said burner is located on the longitudinal axis of the lighter.

14. A lighter according to claim 10, wherein a peripheral wall of said burner housing includes a through bore which is adapted to be covered by the actuator in the inoperative position thereof.

15. A lighter according to claim 1, wherein the aperture in the peripheral wall of said burner housing opens into the interior of said actuator when the latter is in its retracted position thereof and is disposed when said actuator is advanced.

16. A lighter according to claim 11, including a frame within said casing to support said chassis and said burner assembly, said actuator guided between said frame and said casing along liners on said frame, and a return spring interposed between said actuator and said frame.

17. A lighter according to claim 11, wherein said actuator is mechanically coupled to an eccentric which is adapted to be rotated by the gravity when the lighter is inverted.

18. A lighter according to claim 17, wherein said eccentric is movable in response to the movement of said actuator, a bottom wall of said frame provided with an opening to clear said eccentric, and a portion on said frame adapted to be engaged by said eccentric when the latter is rotated.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2986027 *Aug 26, 1958May 30, 1961Scripto IncWindguard structure for pyrophoric cigarette lighter
US3425783 *Nov 8, 1966Feb 4, 1969Mansei Kogyo KkElectric gas lighter having a piezoelectric stack
US3486075 *Feb 7, 1968Dec 23, 1969Bosch Gmbh RobertPiezoelectric igniter
US3826952 *Apr 27, 1973Jul 30, 1974Rion CoHigh voltage generating device
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3989445 *Jul 21, 1975Nov 2, 1976Kojima Precision Parts Co., Ltd.Pencil type gas lighter
US4273528 *Dec 5, 1978Jun 16, 1981Rowenta-Werke, GmbhGas lighter
US6015286 *Jun 30, 1997Jan 18, 2000Windmill Kabushiki KaishaInternal-combustion type of gas lighter
US6206689Aug 25, 1999Mar 27, 2001Bic CorporationChild resistant lighter
US6382960Oct 15, 1998May 7, 2002B I C CorporationChild resistant lighter
US6386860Aug 20, 1999May 14, 2002Bic CorporationChild resistant lighter
US6672861 *Jun 27, 2001Jan 6, 2004Ki-Chul LeePiezoelectric gas lighter having nozzle assembly
US6764299Aug 24, 2001Jul 20, 2004Bic CorporationChild resistant lighter
Classifications
U.S. Classification431/255, 431/88, 431/266
International ClassificationF23Q2/16, F23Q2/28, F23Q2/00, F23Q2/34
Cooperative ClassificationF23Q2/163, F23Q2/287
European ClassificationF23Q2/28C2, F23Q2/16C3