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Publication numberUS3676954 A
Publication typeGrant
Publication dateJul 18, 1972
Filing dateMay 13, 1971
Priority dateMay 13, 1971
Publication numberUS 3676954 A, US 3676954A, US-A-3676954, US3676954 A, US3676954A
InventorsFrymire Garold D, Rapport Jerry
Original AssigneeTravel Trim & Vent Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Escape hatch
US 3676954 A
A conventional worm-and-gear operated vent of a recreational vehicle is made operable as an emergency exit by attaching an emergency operating lever that may be rapidly actuated to rotate both the housing of the worm gear drive mechanism and the operating torque shaft that is driven by the mechanism. The housing is rotatably mounted, but normally latched to fix it in position. Operation of the emergency lever achieves both unlatching and rotation of the housing.
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Description  (OCR text may contain errors)

United States Patent Rapport et al.

[54] ESCAPE HATCH [72] Inventors: Jerry Rapport, Long Beach; Garold D.

Frymire, Buena Park, both of Calif.

[73] Assignee: Travel Trim & Vent C0., Compton, Calif.

[22] Filed: May 13, 1971 [21] Appl. No.: 143,002

[52] U.S. Cl ..49/l4l, 49/337 [51] Int. Cl ..E05c 15/02 [58] Field of Search ..49/141, 23, 95, 341, 342, 343,

[56] References Cited UNITED STATES PATENTS 1,050,073 1/l9l3 West ..49/95 [45] July 18, 1972 1,441,358 1/1923 Lampert ..49/343 2,173,475 9/1939 Forman ..49/141 2,311,967 2/1943 Sawyer ..49/l4l X 2,528,953 11/1958 Gzupkaytll ..49/23 Primary Examiner-Kenneth Downey Attorney-Gausewitz, Carr & Rothenberg 57 ABSTRACT 15 Claims, 8 Drawing Figures ESCAPE HATCH BACKGROUND OF THE INVENTION 1. Field ofthe Invention.

This invention relates to window, vent or other closure mechanisms and particularly concerns such arrangements that permit emergency override of normal operating mechanisms.

2. Description of Prior Art In the case of fire or sudden noxious conditions within the interior of a vehicle or building, an emergency exit is required. The usual exit door may not be available or accessible because of the conditions that necessitate escape. To accommodate such emergencies, recreational vehicles, vehicles of public transportation and habitable buildings of various types are often provided with escape exits in the form of special or additional openings formed in a wall or ceiling. These openings are provided with sealing closures that are commonly either ruptured or detached for quick escape. There are frequently employed detachable closure panels or readily fragmented glass closures fixed in place to seal an emergency exit.

The common openings of such buildings and vehicles are of at least three different types. Firstly, one or more doors provide common entrance and exit; secondly, a movable, usually adjustable, closure such as a window or vent provides light and ventilation; and, thirdly, an escape exit frequently provides no function other than emergency use.

Windows and vents are relatively slowly moveable through a variety of individually adjustable positions. They are not readily adapted for emergency exit because of the excessive time required to achieve full opening. Time and effort required to operate such window or vent, particularly those of the worm-and-gear drive type, may mean, literally, the difference between life and death.

The problem of emergency exit is ofincreasing significance, particularly because of the explosively growing use of recreation vehicles. Fire, toxic fumes or lack of oxygen create problems within the exceedingly confined space of the recreation vehicle that greatly minimize time available for evasive action. The usual recreation vehicle carries its own portable cooking and heating equipment and fuel supplies. In such vehicles, not only is the probability of occurrence of a catastrophe increased, but exit must be made even more quickly if escape is to be made at all. The larger the number of emergency exits available, the greater is the probability that one of these may be reached when need is great and time is short. The faster the operation of such emergency exit, the better is the opportunity for safe escape.

Since it is common to provide a number of windows and vents in walls and roofs of recreational vehicles, it would be a significant advantage if one or more of these could perform a second function, namely, that of providing a rapid exit in case of an emergency. However, such windows and vents that are presently known are not designed to afford this rapid emergency function, and, at best, would provide exit only upon slow and laborious destruction of the window or vent.

Accordingly, it is an object of the present invention to provide a closure member that is readily and conveniently adjustable to provide selected light and/or ventilation and which may be rapidly opened when required for emergency exit.

SUMMARY OF THE INVENTION In carrying out principles of the present invention in accordance with a preferred embodiment thereof, a closure member is operated between closed and open positions by a torque shaft and a drive mechanism therefor. The drive mechanism is normally latched to restrain rapid movement, and provision is made to unlatch the mechanism and to directly move both the mechanism and the torque shaft as a unit to achieve emergency opening. In a specific embodiment, a conventional worm-and-gear drive mechanism is carried in a housing that rotatably supports the torque shaft for rotation of a closure operator. The housing is also rotatably mounted but firmly latched in position. An emergency operator is rotatably mounted on the torque shaft and carries cam means that unlatches the housing together with its worm-and-gear drive mechanism and, further, achieves a positive rotation of the housing, its drive mechanism and the torque shaft for emergency operation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a pictorial illustration of a portion of the roof of a vehicle having the emergency closure of the present invention mounted thereon;

FIG. 2 is a plan view of the underside of the escape hatch of this invention;

FIG. 3 illustrates details of the closure operator and its connection with the closure;

FIG. 4 is an exploded view of most of the operating parts of the emergency actuating mechanism of the present invention;

FIGS. 5 and 6 are detailed views of the apparatus in two different positions; and

FIGS. 7 and 8 schematically depict the emergency operating lever and housing, showing their relations to the latching and drive pins in different operating positions.

DETAILED DESCRIPTION Although emergency closures or escape hatches may be mounted in any wall or other exterior structure of a building or vehicle, the arrangement shown for purposes of exposition includes a roof 10 of an emergency vehicle to which is mounted, as by hinges 12, a movable and adjustable vent 14. It should be noted that the term wall" as used herein denotes both normally vertical side or end walls and the usually horizontal roof or overhead wall of the vehicle or building. The location is chosen to meet the most likely needs. In the case of recreational vehicles, accidents or other emergency situations that require rapid egress often involve upset of the vehicle, which may come to rest lying on its side and thus block ordinarily used exits. In such a situation, a quick-opening emergency hatch carried in the roof of the vehicle will allow a prompt escape. For such reasons, it is preferred to locate the escape hatch in the roof of a vehicle.

Closure 14 is preferable transparent, or at least translucent, to provide light when it is closed. It is operated from the closed position illustrated in FIGS. 1 and 5 to an open position, and through and between an unlimited number of intermediate positions, by means of a conventional worm-and-gear mechanism 16 (FIG. 5) that is controlled by a manual knob 18.

As best illustrated in the exploded view of FIG. 4, the operating mechanism comprises a housing formed of half sections 20 and 22 in which are journaled the ends of a bushing 24. The bushing is formed with an hexagonal surface 26 that is irrotationally received in a gear 28. The latter has its teeth engaged with the threads of a worm 30 that is rotatably journaled in a bore 32 formed in the two housing half sections. Two housing mounting brackets 34, 36 are formed with slots 35, 37 that receive screws, bolts or other fastening means (not shown) that fixedly secure the housing together with the worm-and-gear mechanism contained therein to an upstanding peripheral supporting rim 38 (FIGS. 5 and 6) that circumscribes the opening upon which the closure 14 is mounted.

A torque shaft, comprising a first half section 40 extending from one side of the housing and a second half section (not shown in FIG. 4) extending from the other side of the housing, is journaled in an aperture 41 of bracket 34 and is rotatably received in an aperture 43 of housing section 20. The shaft section 40 extends into bushing 24 to which it is fixedly secured. The torque shaft section is a tight fit within bushing 24 and is fixed thereto by means of engagement of inwardly projecting bushing splines 45 with one or more slots 47 formed in the inner end of the torque shaft section. The other half section of the torque shaft extends from the other side of the housing and is formed and secured to the other side of bushing 24 in a like manner.

The two housing halves are secured together by a suitable fastening means (not shown) and thus securely mount the various operating parts in the described relation.

Each torque shaft half section extends outwardly toward the periphery of closure 14 and is fixed at its outer end to a respective one of a pair of bell cranks 44 (of which only one is shown in FIGS. 5, 6) that operate the closure 14. As best illustrated in FIG. 3, each side of closure 14 is formed with a track 48 in which rides a slide 49 that is pivotally carried by the-end of the associated bell crank or closure operator 44.

The structure illustrated and described up to this point operates as a conventional worm-and-gear driven closure-actuating mechanism, provided that the housing 20, 22 is fixed against movement with respect to the support formed by the roof of the vehicle. In this conventional mode of operation, rotation of knob 18 rotates worm 30 which, in turn, rotates gear 28, bushing 24 and both halves of the torque shaft about the axis of the torque shaft. The torque shaft rotates bell crank levers 44, connected to either side of the closure, which thus actuates closure 14 as the lever-carried slides 49 travel in the closure tracks 48. The conventional driving engagement .between worm and worm gear causes the closure to be retained in any position intermediate its full opened and its full closed position, whereby the closure may be used in conventional fashion to provide an adjustable degree of ventilation.

EMERGENCY OPERATING MECHANISM To enable the above-described mechanism to perform a second function, namely, that of rapid operation for emergency exit, the housing 20, 22, together with the worm-and-gear mechanism contained therein, is journaled upon the torque drive shaft and an emergency or panic actuating arm or lever assembly is provided. For normal operation, the housing must remain fixed to the support. Accordingly, the housing is normally latched to the support against rotation relative thereto about the axis of the torque drive shaft. This latching is accomplished by means ofa latching pin 50 (FIGS. 4-8) that extends through a pair of radially extending slots 52, 54 formed in brackets 34, 36, respectively. Housing sections 20 and 22 are formed with first peripheral latching notches 51, 53 in which the latching pin 50 is normally engaged. Thus, with pin 50 extending through the slots 52, 54in the fixed brackets and confined in the peripheral recesses or notches 51, 53 of the housing, no relative rotation of housing and brackets can occur. Pin 50 is normally retained in this latching relation by means of a pair of springs 55, 56 that are connected between the pin and the respective halves of the torque shaft. The springs urge the pin 50 radially toward the inner ends of slots 52, 54 and thus retain the pin in the peripheral recesses of the housing.

A panic arm or emergency operating lever assembly comprises a pair of arms 58, 60 each apertured as at 59, 61 to rotatably receive a respective half of the torque shaft. Suitable hand grips 62, 63 are fixed to the free ends of the respective panic arms 58,60.

The panic arms or levers 58,60 are formed with various surfaces of such configuration as to achieve several operations. Upon rotation of the arms in a clockwise direction, as seen in FIGS. and 6, the arms first unlatch the housing to free it for rotation about the axis of the torque shaft and thereafter, upon further rotation, actually accomplish rotation of the entire housing, its contained mechanism and the torque shafts, all about the axis of the latter. This allows the closure 14 to be rapidly opened without relative motion or operation of the worm-and-gear drive. Thus, a single rapid rotation of the panic or emergency levers unlatches the housing and accomplishes a direct and equal rotation of the closure.

The unlatching operation is performed by a lever cam surface 65 (FIGS. 4, 7) that is formed on an unlatching cam 71 and positioned to engage latching pin 50. As the levers 58, 60 are rotated in a clockwise direction, pin 50 engages cam surface 65 and is cammed radially outwardly in its guiding slots 52, 54 against the resilient resistance of springs 55, 56.

Levers 58, 60 are also formed with a housing drive shoulder 67 arranged for driving engagement with a housing drive pin 68 that is fixedly carried in apertures 69 (FIG. 4) of the respective housing half sections. Drive pin 68 protrudes outwardly from both sides of the housing a distance at least sufficient to assure a firm engagement with the housing drive shoulders of the panic levers 58, 60. Accordingly, after the levers have been rotated through an initial are sufficient to radially displace the latching pin 50 and thus free the housing for rotation about the axis of the torque shaft 40, the housing drive shoulder 67 on the panic arm engages the housing drive pin 68.

In the normal rest position of levers 58, 60, housing drive pin 68 abuts the lower end of a drive slot 81 formed in the panic arm. Driving shoulder 67 forms the upper end of this slot. This normal rest position is illustrated in FIG. 5 and in solid lines in FIG. 7.

After unlatching has been accomplished, continued clockwise rotation of panic levers 58, 60 with housing drive shoulder 67 bearing firmly against housing drive pin 68 causes rotation of the entire mechanism toward the position illustrated in FIG. 6 and in dotted lines in FIG. 7. The housing, the worm and gear mounted therein, both halves of the torque shaft and, of course, the bell cranks fixed to the respective ends of the torque shaft are all directly rotated by continued rotation of the panic levers. Accordingly, a simple upward push upon the panic hand grips 62, 63 (FIG. 2) will achieve a rapid and direct opening of the closure 14 through an angle in the order of 70 to the full open position illustrated in FIG. 6. The total amount of opening and the total degree of rotation achieved through operation of the emergency handles are but a matter of choice or design. The mechanism readily can be designed to allow motion of the closure to an open position of or beyond Presuming that operation of the panic levers 58, 60 is started when the worm and gear are in such a position that the closure 14 is in a full closed position, the emergency operation of the apparatus will continue through some 70 in the arrangement illustrated in the drawings, until the panic arms 58, 60 have moved to a position wherein the surface 70 (FIG. 7) of unlatching cam 71 has passed the floating latch pin 50. The latter is then allowed to be radially retracted along slots 52, 54 by the action of springs 55, 56. Until this point in the rotation, both the panic arms 58, 60 and the housing itself, together with the remainder of the mechanism, have been rotating about the axis of the torque shaft.

A second peripheral notch 72, 74 is formed in the respective half sections of the housing. This second notch is positioned to receive the floating latch pin 50 as it is drawn down past the end 70 of the unlatching cam 71. Now, the latching pin 50 is captured in the second peripheral notch 72, 74 and once again locks the housing to prevent relative rotation of housing and mounting brackets 34, 36. This open, latched position is illustrated in dotted lines in FIG. 8, which shows the rotation of housing 20 by the emergency operation. Accordingly, the apparatus is now latched in the position as illustrated in FIG. 6, with the closure substantially in full open position. When latched in the open position, the apparatus may be returned to normal closed position by counterclockwise rotation oflevers 58, 60. In such operation, surface 70 of unlatching cam 71 drives latching pin 50 from the second notch 72, 74, and surface 80 of drive slot 81 engages housing drive pin 68 to achieve counterclockwise rotation of the housing.

It will be readily understood that this latching of the closure in full open position (as in FIG. 6) is merely an added convenience and is normally not necessary in the functioning of the apparatus for emergency exit. For emergency use, it is merely necessary that the apparatus be capable of rapid opening and, if necessary, may be manually retained in such open position during a panic exit. If the worm-and-gear mechanism previously has been operated to at least partially open closure 14, the panic arms, in the emergency operation, will function exactly as described above except that the second peripheral notch 72, 74 of the housing may not come into play. Accordingly, the closure will not be relatched in its substantially fully opened position. Other than this lack of relatching in open position, the rapid action remains unchanged.

lf deemed necessary or desirable, the described apparatus may be provided with a screen 85 that includes a frame of which only the rear cross member 86 is shown in FIG. 5 The screen frame rests upon a peripheral inwardly extending flange 87 that is fixed to the supporting rim 38. The screen is not disturbed upon ordinary adjustment of the closure by the worm and gear. However, upon emergency operation, hand grips 62, 63, or a hand that grips these handles, will contact the screen to displace it from its normal position (which is illustrated in FIG. 5), causing the screen to move together with the closure. For clarity of illustration, the screen is not shown in FIG. 6. To permit such displacement, the screen may be merely resting upon the flange 87 with no attachment thereto, or with only a light, readily broken attachment. Preferably, if a screen is to be used, it is pivoted to the flange 87 by a hinge pin 88 that permits the screen and its frame to pivot upwardly from the position shown in FIG. 5. This pivotal motion is about an axis parallel to the hinge axis of closure 14.

There has been described an improved closure operating mechanism particularly adaptable for use as an escape hatch, which allows a substantially conventional closure mechanism to perform the dual function of its conventional and normal selectively adjustable operation of the closure and, in addition, the rapid acting emergency opening required in a panic situation. This dual function is achieved by a housing mechanism that is rotatably mounted but normally latched against such rotation. Emergency operation is achieved by causing the panic lever, first, to unlatch the housing and the conventional operating mechanism carried thereby and, second, to rotate the housing together with its conventional mechanism to thereby provide a direct and rapid emergency operation.

The foregoing detailed description is to be clearly understood as given by way of illustration and example only, the spirit and scope of this invention being limited solely by the appended claims.

What is claimed is:

1. Quick opening apparatus comprising:

a Support,

a closure member mounted to the support for motion between closed and open positions,

a housing journaled to said support,

a torque shaft connected in driving relation to the closure member so as to move said closure member between said open and closed positions upon rotation of the shaft,

shaft drive means mounted to the housing and having a driving connection to the shaft whereby operation of said shaft drive means will rotate said torque shaft to move said closure relative to said support,

latch means for selectively restraining motion of said housing relative to said support, and

emergency operating means for disengaging said latch means to free said housing for motion with respect to the support, said emergency operating means including means for rotating both said housing and said torque shaft relative to the support, whereby said closure member may be operated rapidly by said emergency operating means without operating said shaft drive means.

2. The apparatus of claim 1 wherein said shaft drive means comprises 1 a gear rotatably mounted in the housing and fixed to said torque shaft, and

a gear driving worm rotatably mounted in the housing and operatively engaged with said gear, whereby upon operation of said worm said closure may be operated to and between said opened end closed positions and to and between substantially any intermediate portion thereof, and said closure may be retained in any one of said positrons.

3. The apparatus of claim 2 wherein said journaled connection of said housing to said support comprises said torque shaft and means for rotatably mounting said torque shaft to said support and to said housing, whereby said torque shaft may rotate relative to both said support and housing upon operation of said worm when said latch means is engaged to restrain motion of said housing and may rotate together with said housing relative to said support when said latch means is disengaged.

4. The apparatus of claim 1 wherein said latch means comprises a notch formed in the periphery of said housing,

a guide in said support extending radially of said torque shaft and having at least a portion thereof in registry with said notch when said housing is in a first position thereof,

a latch pin mounted in said guide for radial motion relative to said torque shaft and extending into and captured within said notch when said housing is in said first position thereof, and

said means for urging said latch pin along said guide into said notch, said emergency operating means including cam means for driving said latch pin along said guide from said notch upon motion of said operating means, to thereby free said housing for pivotal motion with respect to said support about the axis of said torque shaft.

5. The apparatus of claim 4 including an emergency drive surface on said housing,

said emergency operating means including means for engaging said emergency drive surface to effect rotation of said housing about the axis of said torque shaft upon operation of said emergency operating means.

6. The apparatus of claim 5 wherein said emergency operating means comprises a lever journaled for rotation about the axis of said torque shaft,

and wherein said cam means comprises a cam shoulder on the lever for engagement with said latch pin to drive said latch pin from said notch upon rotation of said lever about the axis of said torque shaft.

7. The apparatus of claim 6 wherein said means for engaging said emergency drive surface includes a housing drive shoulder on said lever positioned adjacent to but spaced from said emergency drive surface when said lever cam shoulder is in contact with said latch pin, whereby upon rotation of said lever the latch pin will be driven from said notch by said cam shoulder before engagement of said housing drive shoulder with said emergency drive surface, and whereby upon further rotation of said lever engagement of said housing drive shoulder thereof with said emergency drive surface will rotate the housing together with the torque shaft relative to the support.

8. The apparatus of claim 7 wherein said housing is formed with a second notch in the periphery thereof for receiving said latch pin after said housing has been rotated by said emergency operating means to a second position wherein said torque shaft has actuated said closure member to an open position thereof, whereby when said housing is in said second position said latch pin is urged radially inwardly into said second notch of said housing to thereby latch said housing, said torque shaft and said closure member in such position. v

9. The apparatus of claim 8 wherein at least one of said lever and said housing includes a peripheral surface that engages said latch pin when the latter has been driven from said first notch and that retains said latch pin in said radially displaced position until said housing has been rotated through an angle sufficient to substantially open said closure member.

10. A quick opening closure assembly comprising a frame having an opening therethrough of a size sufficient to allow emergency egress,

a closure member pivoted to said frame for movement between a first position in which said opening is blocked and a second position in which said opening is unblocked by an amount at least sufficient to permit such emergency egress,

a pair of brackets fixed to the frame,

a torque shaft journaled in said brackets,

said torque shaft having a driving connection to said closure member whereby upon rotation of said torque shaft said closure member is pivoted between said positions thereof,

a housing journaled on said torque shaft between said brackets,

a drive mechanism carried by said housing and including a gear fixed to said torque shaft and a manually operable worm in driving engagement with said gear,

a latch mechanism interconnecting at least one of said brackets and said housing to restrain rotation of the housing about the axis of said torque shaft, and

an emergency operating lever journaled on said torque shaft for disengaging said latch mechanism and rotating both said housing and torque shaft about the axis of said shaft, whereby emergency opening of said closure member may be accomplished without operation of said worm-andgear drive mechanism and regardless of said worm-andgear drive mechanism by rotation of said emergency operating lever to rotate said housing, said torque shaft and said closure member.

11. The apparatus of claim 10 wherein said latch mechanism comprises a guide slot in said one bracket extending radially of said torque shaft,

a pin mounted for movement within said slot,

a spring connected to urge said pin radially inwardly of said torque shaft, and

an outwardly opening peripheral notch in said housing,

said notch being in registry with the radially inward end of said slot and receiving said pin when said housing is in a first position thereof with respect to said one bracket, whereby the spring tends to retain the pin within the peripheral notch of the housing to prevent relative rotation between the housing and said one bracket.

12. The apparatus of claim 11 wherein said emergency operating lever includes a cam shoulder formed on the periphery thereof for engagement with said pin to force said pin from said peripheral notch when said emergency operating lever is rotated,

13. the apparatus of claim 12 including a drive pin extending from said housing in a direction substantially parallel with the axis of said torque shaft,

and wherein said emergency operating lever includes a drive shoulder positioned to engage said drive pin after the emergency operating lever has been rotated through a relatively small distance sufficient to cause said cam shoulder to force said latch pin from said peripheral notch, whereby the housing will be rotated by means of engagement of said emergency operating lever drive shoulder with said drive pin after said housing has been unlatched.

14. The apparatus of claim 13 wherein said housing has a second radially outwardly opening peripheral notch to receive said latch pin after the latter has been driven from said first notch and after the housing has been rotated by means of said emergency operating lever through an angle sufficient to rotate said torque shaft and move said closure member to its second position.

15. The apparatus of claim 10 including a screen mounted in said opening for pivotal motion about an axis parallel to the pivot axis of said closure member, whereby rotation of said emergency operating lever to rotate said closure member will cause said lever or a hand gripping said lever to contact said screen and to rotate said screen together with said closure member.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1050073 *Jul 5, 1912Jan 7, 1913Ross R WestWindow-operating device.
US1441358 *Oct 5, 1921Jan 9, 1923Lampert Henry HCowl ventilator
US2173475 *Nov 30, 1935Sep 19, 1939Nat Pneumatic CoDoor-operating mechanism
US2311967 *Nov 21, 1938Feb 23, 1943Sawyer Emerson DHorizontal swinging gate-supported yieldable barrier
US2528953 *Mar 22, 1949Nov 7, 1950Matt GzupkaytiiWindow operator construction
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4021073 *Mar 18, 1976May 3, 1977Manning Donald LCombined vent and escape hatch
US4412404 *Apr 19, 1982Nov 1, 1983Transpec, Inc.Combined vent and escape hatch
US5956901 *Jun 24, 1997Sep 28, 1999Northrop Grumman CorporationGas driven hatch cover assembly
US8328137Oct 21, 2008Dec 11, 2012Airbus Operations GmbhEmergency exit hatch for exiting a cabin module in an emergency and entering the same
US8827349Oct 5, 2012Sep 9, 2014Chrysler Group LlcFlip-over window assembly for vehicle
DE2717063A1 *Apr 18, 1977Oct 19, 1978Donald Lee ManningCombined vent and escape hatch for vehicle roof - is hinged by two sets of toggle linkages and has one hinge bracket with two separable darts
EP0092411A2 *Apr 18, 1983Oct 26, 1983Transpec, Inc.Combined vent and escape hatch
U.S. Classification49/141, 49/337
International ClassificationE05B65/10
Cooperative ClassificationE05B65/1033
European ClassificationE05B65/10E