Patent Description:
Draft shields are common in precision weight measurements. They serve to protect the weighing pan and weighing goods from external influences, such as, for instance, agitated air, which could in turn exert forces on the weighing pan and weighing good and thus detrimentally influence the measurement precision. It will be readily appreciated that agitated air influences the measurement, or weight determination, the stronger the lower the weight to be determined is.

Draft shields require doors to allow access to the interior of the draft shield when the draft shield is disposed on a balance. This interior is also referred to as the weighing chamber. The weighing pan and the weighing good are enclosed inside the weighing chamber and thus protected from external influences. Sliding door members are frequently used in connection with draft shields and yield several advantages which are not to be discussed within the framework of the present document.

From time to time, the door members of draft shields may need to be removed for cleaning and other purposes. In particular in connection with sliding door members also the sliding mechanism of the door may be found subject to soiling, which might, beside other potential detrimental effects, inhibit hitchless operation of the door member.

It might thus be desirable to provide a mechanism which, on the one hand, safely secures the sliding door member to the sliding mechanism during normal operation, while on the other hand allowing easy removal and re-insertion of the door member from and into the sliding mechanism.

<CIT> discloses a draft shield for a balance, comprising a rear wall, rails extending forward from top corners of the rear wall, the rails containing guide tracks for a top cover panel and two sidewalls. Locking elements are arranged at front ends of the rails. A top cover panel is slidably installed into corresponding guide tracks in the rails. The draft shield further comprises two sidewalls, each sidewall slidably installed into corresponding guide tracks in the rails. A seat is provided for receiving a portion of a front wall, wherein a bottom edge of the front wall is inserted into the seat. The front wall is secured in flush alignment against the top cover panel and the sidewalls by the locking elements. The sidewalls and/or the top cover panel are fully removable from the remainder of the assembly by pulling the same forward through the respective guide tracks and out the front ends of the rails when the locking elements for locking the front wall are released. According to the teaching of <CIT>, an electronic balance with a draft shield having a door member to be automatically smoothly opened and closed is disclosed. In the housing, an end portion at the side opposite the end portion at the side from which the contact portion protrudes is a grip portion to be gripped when inserting and pulling out the engagement member. Holes are formed so as to become orthogonal to the side wall portions of the housing, and inside the holes, a pair of left and right lock pins are disposed. Both of the lock pins are energized so as to protrude to the outer sides of the side wall portions by an elastic body such as a coil spring interposed between the lock pins. The lock pins are energized so as to protrude outside by the coil spring and engage with the locking recess portions and fix the engagement member at the position of the locking recess portions. In this state, the contact portion of the flat plate is not in engagement with the floor member and the draft shield is detachable from the balance main body. According to the teaching of <CIT>, a draft shield comprises side panels, a fastening lock, vertical columns in the rear part of the weighing chamber and a weighing chamber structure supported on columns. The weighing chamber is locked using a fastening lock located in the structure comprising the guides for the top and side panels. First a nut or a screw is unscrewed holding the angle bracket protecting the back edge of the top panel against sliding out. An embodiment with a nut in the top structure features a threaded mandrel for screwing a nut. After removing an angle bracket, a space is created under which a pad can pass while sliding. Sliding out the top panel unlocks the back panel and enables removing the back panel from the groove in the chamber basis without using force.

Further prior art is given by patent document <CIT>.

As is readily apparent from the description above, in the art it is a fairly complex task and requires an abundance of manual actions to remove doors from and to reinstall them in a draft shield. It is found desirable to facilitate removing and reinstalling door members from and in a draft shield.

It is one object of the present disclosure to suggest the subject matter initially mentioned. In a more specific aspect, a guideway for receiving and guiding a carriage shall be suggested which enables for instance a door member of a draft shield to be conveniently removed from and mounted to the draft shield, and on the other hand to safely lock the door member to the guideway, or the draft shield, respectively, during operation.

This is achieved by the subject matter described in claim <NUM>.

Further effects and advantages of the disclosed subject matter, whether explicitly mentioned or not, will become apparent in view of the disclosure provided below.

Accordingly, disclosed is a guideway configured for receiving and guiding a carriage. The guideway may in particular be a linear guideway. The guideway may also be called a rail containing a guide track. The carriage for which the guideway is configured may be a carriage comprising wheels, or a trolley, so as to roll on tracks of the guideway. In other embodiments, however, the guideway may be configured to receive a carriage without wheels, such that the carriage slides on tracks of the guideway. The guideway comprises a guideway body having a first longitudinal end and a second longitudinal end. The guideway body comprises a longitudinally extending clear channel which is bordered by a wall of the guideway body. The longitudinally extending clear channel opens at the first longitudinal end of the guideway body. Further, the guideway comprises a stop member terminating the guideway at the first longitudinal end of the guideway body. The stop member comprises a crossbar and two legs extending from the crossbar. The crossbar extends transverse to a longitudinal direction of the clear channel and the legs extend transverse to the longitudinal direction of the clear channel and transverse to the crossbar. In particular, the legs may extend at least essentially perpendicular to the crossbar. The legs have a clearance between them, in particular defining a clear width between the legs. The stop member hence forms a frame enclosing a window, wherein the stop member has an opening on an edge of the window transversely opposite the crossbar, thus defining an open side of the stop member. Said clearance may be dimensioned such that a carriage received inside the clear channel of the guideway body may pass through the clearance between the two legs. The window may be dimensioned such that a carriage received inside the clear channel of the guideway body may pass through the clearance between the two legs. The stop member is displaceable on the guideway body at least essentially perpendicular to the crossbar and transversely relative to the guideway body, or the longitudinal extent thereof, respectively, and between at least two transverse positions. In at least one of the at least two transverse positions the crossbar at least partially overlaps with the clear channel of the guideway body, or the cross section thereof, respectively. In at least a second of the at least two transverse positions the window of the stop member at least partially overlaps with the clear channel of the guideway body. The stop member, and the transverse displaceability thereof, are in aspects configured such that in at least one first transverse position the crossbar, due to partially overlapping the cross section of the channel of the guideway body, restricts a clear passage of the clear channel at the first longitudinal end of the guideway body, and thus may retain at least a portion of a carriage intended for being received within and guided by the guideway inside the guideway body. In at least one second transverse position, however, displacement of said carriage portion through the clear passage of the clear channel at the first longitudinal end of the guideway body is enabled. In particular embodiments, it may be provided that the crossbar of the stop member in the at least one second position has no overlap with the cross section of the guideway clear channel. More in particular, it may be provided that the legs are laterally offset from lateral edges of the clear channel in a view onto a cross-section thereof, or an longitudinal view on the guideway body, respectively. It may thus be provided that in at least one second transverse position of the stop member on the guideway body the cross section of the clear channel of the guideway body is completely open at the first longitudinal end of the guideway body, i.e., there is no overlap between the stop member and the cross section of the guideway body clear channel.

At a second longitudinal end of the guideway body the clear channel of the guideway body may be permanently closed.

It is noted that within the framework of the present disclosure the use of the indefinite article "a" or "an" does in no way stipulate a singularity nor does it exclude the presence of a multitude of the named member or feature. It is thus to be read in the sense of "at least one" or "one or a multitude of".

It is moreover noted that in the context of the present application the terms "neighbouring", "bordering" and "adjacent" as well as "neighbouring", "bordering" and "adjacent to" are considered as synonyms.

It may be provided that the guideway body has a longitudinally extending slot in at least one longitudinal surface of the guideway body. The guideway body thus is provided with at least one longitudinally extending slot. At least one of the longitudinally extending slots extends through the wall of the guideway body, whereby the clear channel of the guideway body opens at at least one of the at least one longitudinal surface of the guideway body. The longitudinally extending slot in particular extends in a longitudinal direction of the guideway body. The crossbar of the stop member is arranged transversely opposite a first longitudinally extending slot of the at least one longitudinally extending slot which extends through the wall of the guideway body. Consequently, said first longitudinally extending slot is disposed on the guideway on a side opposite the crossbar of the stop member. Said first longitudinally extending slot is open at a first longitudinal edge of the longitudinal surface on which it is disposed, and proximate the first longitudinal end of the guideway body, such that said longitudinally extending slot joins into the opening of the clear channel of the guideway body at the first longitudinal end of the guideway body on which the stop member is provided.

A cross-section of the guideway body may be polygon-shaped, wherein the first longitudinally extending slot of the guideway body which is disposed on the guideway on a side opposite the crossbar of the stop member is provided through the wall of the guideway body and is laterally edged by at least one ledge. The at least one ledge may be at least one residual wall segment of one surface of the guideway body. The at least one ledge, or an inward surface of each of the at least one ledge, may form at least one track for supporting a carriage. The cross section of the guideway body may be rectangular or quadratic, wherein corners of the cross-sectional shape of the guideway body may be rounded or chamfered.

The first longitudinal end of the guideway body is shaped such that a longitudinal terminal edge of the guideway body on the side on which the open edge of the window of the stop member is disposed is set back relative to the longitudinal terminal edge of the guideway body on the side on which the crossbar of the stop member is disposed.

In embodiments, the stop member and the guideway body comprise at least one pair of functionally interacting means through which the stop member is guided in the direction of the transverse displacement of the stop member relative to the guideway body when the stop member is mounted to the guideway body. (<NUM>) It may be provided that the displaceability of the stop member relative to the guideway body is purely in a transverse direction, whereby the stop member, respectively, is fixed in a longitudinal direction relative to the guideway body.

In further non-limiting embodiments, the stop member is transversally displaceable between a first transverse end position and a second transverse position, wherein, in the first transverse end position, the crossbar of the stop member has a larger overlap with the clear channel of the guideway body than in the second transverse position. As suggested above, it may more in particular be provided that the at least one second transverse position includes a transverse position in which the crossbar of the stop member has no overlap with the clear channel of the guideway body.

The attachment arrangement of the stop member to the guideway body may be adapted and configured such that a restoring force directed towards the first transverse end position acts on the stop member when it is displaced from the first transverse end position towards the second transverse position. Thus, the stop member may be forced the first transverse end position by the restoring force. (<NUM>) To this extent it may in a more specific aspect be provided that the guideway body and the stop member comprise at least one sloped surface section on one of the guideway body and the stop member. A counterpart support feature configured to contact a respective one of the at least one sloped surface section, when the stop member is mounted to the guideway body, is provided on the other one of the guideway body and the stop member. The at least one sloped surface section is sloped along, i.e., parallel to, the direction of the transverse displaceability of the stop member relative to the guideway body. The at least one sloped surface section and the counterpart support feature are jointly configured to elastically deform the stop member when the stop member is transversely displaced from the first transverse end position so as to generate the restoring force when the stop member is transversely displaced from the first transverse end position.

Further disclosed is a sliding door arrangement comprising a door member and a guideway of any kind outlined above. The door member is provided with a carriage at a first edge of the door member. The carriage is adapted and configured to be received inside the clear channel of the guideway body. The stop member is configured such that the stop member blocks the clear channel against at least a portion of the carriage passing through an open end of the clear channel at the first longitudinal end of the guideway body in at least one lock position of the stop member, thereby being configured to retain at least a portion of the carriage inside the clear channel of the guideway body, and to allow the entire carriage to pass through the open end of the clear channel at the first longitudinal end of the guideway body in at least one release position of the stop member. The lock position and the release position may in particular be transverse positions of the stop member relative to the guideway body. A sheet of the door member may extend from the carriage and through a longitudinally extending slot provided in a longitudinally extending surface of the guideway body. (<NUM>) The at least one lock position of the stop member may include the first transverse end position referred to above and the at least one release position of the stop member may include at least one of the at least one second transverse position of the stop member referred to above.

The carriage may comprise at least two wheels configured to be supported and roll on at least one ledge laterally edging a longitudinally extending slot provided in a longitudinally extending surface of the guideway body. In certain specific embodiments, the carriage may comprise exactly two wheels asymmetrically provided on one lateral side of the carriage. In other embodiments, at least two wheels may be are provided on a first lateral side of the carriage, while at least one wheel may be provided on an opposite lateral side of the carriage. In more specific embodiments, the carriage may comprise at least two pairs of at least essentially coaxially arranged wheels. In even more particular embodiments, the carriage may comprise exactly two pairs of at least essentially coaxially arranged wheels.

In yet another aspect, disclosed is a draft shield comprising a sliding door arrangement as outlined above, wherein the sliding door arrangement provides a sliding door member of the draft shield. (<NUM>) More in particular, the guideway may be arranged on a top side of the sliding door arrangement, whereby the sliding door member is suspended from the guideway and the carriage is supported by at least one of the at least one ledge laterally edging the first longitudinally extending slot provided in a longitudinally extending surface of the guideway body. The first longitudinally extending slot may in particular be provided on the side of the guideway opposite the crossbar of the stop member. A sheet of the door member and the first longitudinally extending slot of the guideway body may be jointly configured to allow the sheet of the door member to move in the first longitudinally extending slot of the guideway body. The sliding door arrangement may in particular comprise a door member with a carriage comprising wheels which are configured to be supported and roll on the at least one ledge. The skilled person will readily appreciate well-defined positions or directions like "top", "bottom" or "side" in connection with a draft shield, as a draft shield has a well-defined orientation in which it is used in connection with a balance, while a balance, as a matter of course, has clearly defined top and bottom orientations which are prescribed by the function of the balance.

The draft shield may further comprise a means for guiding a second edge of the door member opposite the first edge of the door member comprising the carriage. Said means for guiding a second edge of the door member may in particular be configured such as to restrict movement of the second edge of the door member across a longitudinal direction of the guideway and be provided to inhibit a pendular movement of the door member when it is suspended by the carriage received inside the guideway.

It is understood that the features and embodiments disclosed above may be combined with each other. It will further be appreciated that further embodiments are conceivable within the scope of the present disclosure and the claimed subject matter which are obvious and apparent to the skilled person by virtue of the present disclosure.

The subject matter of the present disclosure is now to be explained in more detail by means of selected exemplary embodiments shown in the accompanying drawings. The figures show.

It is understood that the drawings are highly schematic, and details not required for instruction purposes may have been omitted for the ease of understanding and depiction. It is further understood that the drawings show only selected, illustrative embodiments, and embodiments not shown may still be well within the scope of the herein disclosed and/or claimed subject matter.

<FIG> shows an exemplary embodiment of a weighing system <NUM> comprising a balance <NUM> and an exemplary embodiment of a draft shield <NUM>. Balance <NUM> comprises a housing <NUM> in which, for instance, a load cell and electronics are contained. Further, balance <NUM> comprises a display and operator control panel <NUM> on a front side thereof. The load cell is the transducer which transforms a mechanical input from a weighing good placed on a weighing pan into an electric signal. It is understood that draft shield <NUM> is a separate member and may be selectively attached to and detached and removed from balance <NUM>. A housing of draft shield <NUM>, in the shown exemplary embodiment, comprises front wall <NUM>, back wall <NUM>, top wall <NUM>, and side door members <NUM> and <NUM>, which are parts of a housing of draft shield <NUM>. Door member <NUM> is provided on a side of the housing of draft shield <NUM> which is not visible in the present depiction, but, as the skilled person will readily appreciate, is a mirrored version of door member <NUM> is provided in a side of the housing of draft shield <NUM> opposite door member <NUM>. Front wall <NUM>, back wall <NUM> and top wall <NUM> are supported and held in place by columns at corners of the housing of draft shield <NUM>, of which only column <NUM> is visible in the present depiction. Side doors comprising door members <NUM> and <NUM> are sliding doors, which open and close by a sliding movement guided by guideways, such as upper guideway <NUM> and lower guideway <NUM> of door member <NUM>, and upper guideway <NUM> of door member <NUM>, wherein the lower guideway of door member <NUM> is not visible in the present depiction. Side door member <NUM> is slidably guided in upper guideway <NUM> and lower guideway <NUM>. Side door member <NUM> is slidably guided in upper guideway <NUM> and a lower guideway of door member <NUM>. Door members <NUM> and <NUM> are provided to selectively close draft shield <NUM>, and thus encase a weighing chamber inside the housing of draft shield <NUM>, and open draft shield <NUM> to provide access into the weighing chamber. In the present depiction, door member <NUM> is in an open position, while door member <NUM> is in a closed position. Further, power supply and signal transmission terminals <NUM> are provided on the back of balance <NUM>. As outlined in more detail below, door member <NUM> is suspended inside upper guideway <NUM> by carriage <NUM> received inside guideway <NUM>. In the presently shown embodiment, when door member <NUM> is in its open position, carriage <NUM> may partly extend out of guideway <NUM> at a longitudinal end of guideway <NUM>. Guideway <NUM> comprises guideway body <NUM> and stop member <NUM> terminating guideway <NUM> at a first longitudinal end of guideway body <NUM>, which is outlined in more detail below. Likewise, guideway <NUM> comprises guideway body <NUM> and stop member <NUM> terminating guideway <NUM> at a first longitudinal end of guideway body <NUM>. While guideway <NUM> is not explicitly outlined, the skilled person will readily appreciate design of function of guideway <NUM> by virtue of the outline of design and function of guideway <NUM> below.

Reference is now made to <FIG> is a sectional view of a part of draft shield <NUM> taken along a plane and view direction as indicated by A-A in <FIG>. <FIG> depicts an interior of guideway <NUM> with a first portion <NUM> of carriage <NUM> received inside a clear channel of guideway body <NUM>. Guideway <NUM> is supported on columns <NUM> and <NUM> which are provided on corners of the housing of draft shield <NUM>. Door member <NUM> is in a most opened position. Stop member <NUM> is in a lock position, in which first portion <NUM> of carriage <NUM> is retained inside guideway body <NUM>. Stop member <NUM> comprises a lock plate <NUM>, which, when the stop member is in the lock position, at least partially overlaps with clear channel <NUM> of guideway body <NUM>, or a cross section of clear channel <NUM>, respectively. A shoulder of first portion <NUM> of carriage <NUM> adjacent second portion of <NUM> of carriage <NUM> abuts lock plate <NUM>, and thus lock plate <NUM> of stop member <NUM> prevents door member <NUM> from traveling further into the open direction, while retaining first portion <NUM> of carriage <NUM> inside guideway <NUM>. Carriage <NUM> is provided as a trolley comprising wheels <NUM> and <NUM>. Guideway body <NUM>, in the present embodiment, comprises guideway jacket <NUM> and guideway duct <NUM>. A cross-section of guide body <NUM> is shown in <FIG>. Guideway duct <NUM> is inserted into guideway jacket <NUM>. Guideway jacket <NUM>, in the illustrative embodiment is essentially U-shaped and comprises one open longitudinally extending surface of guideway jacket <NUM>. Guideway duct <NUM> forms a wall bordering clear channel <NUM> of guideway body <NUM>. One longitudinal surface of guideway duct <NUM>, on the side where guideway jacket <NUM> is open, constitutes a longitudinal surface of guideway body <NUM> and comprises a longitudinally extending slot <NUM>. Longitudinally extending slot <NUM> extends and is open at a first longitudinal end of said longitudinal surface of guideway duct <NUM> and thus is also open at a first longitudinal end of guideway body <NUM>, on which stop member <NUM> is disposed. Longitudinally extending slot <NUM> is laterally edged by ledge <NUM>. Ledge <NUM> is configured to support wheels <NUM> and <NUM> shown in <FIG> inside guideway duct <NUM> and essentially provide tracks of the guideway on their inward surfaces. Wheels <NUM> and <NUM> may be supported and configured to roll on ledge <NUM>. A sheet <NUM> of door member <NUM> extends through longitudinally extending slot <NUM> and is displaceable in the longitudinal direction of guideway <NUM> and guideway body <NUM>. It will be appreciated that door member <NUM> is non-symmetrically suspended by guideway <NUM>. Thus, when door member <NUM> is suspended by carriage <NUM>, with wheels <NUM> and <NUM> being supported on ledge <NUM>, sheet <NUM> of door member <NUM> tilts with a lower end of sheet <NUM> towards the side of door member <NUM> on which wheels <NUM> and <NUM> are supported by ledge <NUM>. Guideway <NUM> is mounted to the housing of draft shield <NUM> such that ledge <NUM> is arranged on an inner side with respect to the housing of draft shield <NUM>, while longitudinally extending slot <NUM> is offset towards an outer side with respect to the housing of draft shield <NUM>. Thus, sheet <NUM> the lower edge of sheet <NUM> of door member <NUM> is biased towards the center of the housing of draft shield <NUM>. This in turn is helpful in reducing residual gaps between sheet <NUM> of door member <NUM> and the stationary walls of the housing of draft shield <NUM> and thus further enhances the tightness of draft shield <NUM> when doors <NUM> and <NUM> are closed and hence the protection of the weighing chamber inside draft shield <NUM> from external influences. In other embodiments, guideway duct <NUM> may be provided a shown in <FIG>, longitudinally extending slot <NUM> micht be edged by two ledges <NUM> and <NUM>. A carriage <NUM> being asymmetrically equipped with two wheels <NUM> and <NUM> on one lateral side of carriage <NUM> only might advantageously be inserted into clear channel <NUM> of guideway body <NUM> with wheels <NUM> and <NUM> being supported on the ledge out of the two ledges <NUM> and <NUM> which is arranged on an inner side with respect to the housing of draft shield <NUM>, such that the above-mentioned beneficial enhancement of tightness is achieved. In other embodiments comprising a guideway body <NUM> as outlined in <FIG> at least one further wheel may be arranged on an opposite lateral side of carriage <NUM>. Wheels <NUM> and <NUM> may be configured to be supported and roll on a first one of ledges <NUM> and <NUM>, while the at least one wheel arranged on the opposite lateral side of carriage <NUM> may be configured to be supported and roll on the other one of ledges <NUM> and <NUM>. Door member <NUM> may thus be symmetrically suspended by wheels being supported on both ledges <NUM> and <NUM>.

As can be clearly seen in <FIG>, when stop member <NUM> is in the lock position, a second portion <NUM> of carriage <NUM> is enabled to travel out of guideway body <NUM>, and, of course, back into guideway body <NUM>, through a residual opening, i.e. clear passage, of clear channel <NUM> at the first longitudinal end of guideway body <NUM>. First portion <NUM> of carriage <NUM>, however, is retained inside guideway body <NUM>. Thus, door member <NUM> is securely retained by the guideway, such that, on the one hand, a maximum open position of door member <NUM> is defined, and, on the other hand, door member <NUM> cannot unintentionally be removed from the guideway, or, in embodiments, with reference to <FIG>, from draft shield <NUM> when opening door member <NUM>.

If, however, the door member needs to be removed for, for instance, cleaning purposes, the herein disclosed subject matter facilitates removal and re-installation of the door member, without tooling, and with easy manual operations. In another aspect, the herein disclosed subject matter guaranties secure locking of the door member when the carriage, at least a portion thereof, is received in the guideway and, in embodiments, when the door member is attached to the draft shield. This is achieved in that the stop member is displaceable on the guideway body perpendicular to the crossbar and transversely relative to the guideway body, between at least two transverse positions. For a complete appreciation, reference is now made to <FIG>. As seen in <FIG>, stop member <NUM> comprises a crossbar <NUM> and two legs <NUM> and <NUM> extending from crossbar <NUM>. Stop member <NUM> forms a frame enclosing a window. Stop member <NUM> has an opening on an edge of the window transversely opposite crossbar <NUM>, thus defining an open side of the stop member. Displaceability of stop member <NUM> relative to the guideway body is provided perpendicular to crossbar <NUM>. Lock plate <NUM> forms part of crossbar <NUM>. Stop member <NUM> is received on guideway body <NUM>, in the exemplary embodiment on guideway jacket <NUM>. <FIG> illustrates stop member <NUM> in its stop position, wherein crossbar <NUM>, comprising lock plate <NUM>, at least partially overlaps with clear channel <NUM>, or a projection thereof, respectively. In other word, crossbar <NUM> including lock plate <NUM> restricts a clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM>. Said overlap, in the lock position, is configured such that, with reference to <FIG>, a shoulder of first portion <NUM> of carriage <NUM> inside clear channel <NUM>, abuts crossbar <NUM>, or lock plate <NUM> thereof, respectively, and at least partially restricts a clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM>. Guideway jacket <NUM> of guideway body <NUM> comprises two sloped surface sections <NUM> and <NUM> which taper towards the side on which the open edge of stop member <NUM> is disposed. Stop member <NUM> comprises counterpart support features <NUM> and <NUM> configured to contact the respective sloped surface section <NUM> and <NUM> when stop member <NUM> is mounted to guideway body <NUM>, or, more specifically, guideway jacket <NUM>, in the present exemplary embodiment, respectively. As will become more readily apparent by virtue of the description below, when displacing stop member <NUM> in the direction towards crossbar <NUM>, the overlap of lock plate <NUM> with clear channel <NUM> decreases, or, in other words, the clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM> increases so as to eventually allow first portion <NUM> of carriage <NUM> to pass through the clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM>. Further, as will be readily appreciated, when stop member <NUM> is displaced transversely relative to guideway jacket <NUM> in a direction towards crossbar <NUM>, counterpart support features <NUM> and <NUM> will slide in the same direction along sloped surface sections <NUM> and <NUM>. Consequently, legs <NUM> and <NUM> will open and experience elastic deformation. Due to said elastic deformation, legs <NUM> and <NUM>, through counterpart support features <NUM> and <NUM> interacting with sloped surface sections <NUM> and <NUM>, will exert a restoring force when stop member <NUM> is released. Thus, stop member <NUM> will return to the first transverse end position as shown in <FIG>, with crossbar <NUM> abutting guideway body <NUM>, or guideway jacket member <NUM>, respectively.

Guideway jacket <NUM> further comprises end stop shoulders <NUM> and <NUM>, which limit the transverse displacement of stop member <NUM> relative to guideway body <NUM> in the direction towards crossbar <NUM> and defines a second transverse end position of stop member <NUM>.

<FIG> show the arrangements of <FIG> with stop member <NUM> in a release position. As is seen in <FIG>, first portion <NUM> of carriage <NUM> is able to pass besides lock plate <NUM> and through the clear passage of clear channel <NUM> at the longitudinal end of guideway body <NUM>. With reference to <FIG>, it is seen that in this release position lock plate <NUM> of crossbar <NUM> has no overlap with clear channel <NUM>, such that a clear passage of clear channel <NUM> at the longitudinal end of guideway body <NUM> is unrestricted. In the release position shown in <FIG>, counterpart support features <NUM> and <NUM> of stop member <NUM> abut end stop shoulders <NUM> and <NUM> of guideway jacket <NUM>. Thus, the shown transverse position of stop member <NUM> is a second transverse end position. It may be the case, in certain embodiments, that lock plate <NUM> in the second end position still has a certain overlap with clear channel <NUM>, as long as the residual clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM> is dimensioned to allow first portion <NUM> of carriage <NUM> to pass besides lock plate <NUM> and through the clear passage of clear channel <NUM> at the longitudinal end of guideway body <NUM>. <FIG> illustrates how second portion <NUM> of carriage <NUM> may travel through the clear passage of clear channel <NUM> at the first longitudinal end of guideway body <NUM>. It can be seen that one edge of the crossbar, or lock plate <NUM> thereof, respectively, is supported on an edge <NUM> of first portion <NUM> of carriage <NUM>. Thus, once an operator has displaced, starting at the situation shown in <FIG>, stop member <NUM> to a release position, and once the shoulder of first portion <NUM> of carriage <NUM> adjacent second portion <NUM> of carriage <NUM> has travelled out of clear channel <NUM>, stop member <NUM> is supported on edge <NUM> of the first portion <NUM> of carriage <NUM>. Thus, the operator has no longer to actively hold stop member <NUM> in the release position and has both hands free to handle door member <NUM>.

With reference to <FIG> it is illustrated how carriage <NUM> might be reinserted into guideway <NUM> and door member <NUM> may thus, in embodiments, be re-attached to the draft shield. Guideway duct <NUM> is shorter than guideway jacket <NUM>. Thus, guideway body <NUM> is shaped such that a longitudinal terminal edge of guideway body <NUM> on the side on which the open edge of stop member <NUM> is disposed is set back relative to the longitudinal terminal edge of guideway body <NUM> on the side on which the crossbar of stop member <NUM> is disposed. Consequently, guideway body <NUM> has a portion adjacent the first longitudinal end of guideway body <NUM> which is open along a portion of the longitudinal side of the guideway body opposite the crossbar. Hence, an operator may may insert carriage <NUM>, with the end on which wheel <NUM> is disposed, into said open portion on the longitudinal side of the guideway body opposite the crossbar adjacent the first longitudinal end of guideway body <NUM>. The operator may further insert sheet <NUM> of door member <NUM> into the longitudinally extending slot of guideway duct <NUM> opposite the crossbar of stop member <NUM>. Subsequently, the operator may prop up said end of carriage <NUM> on the tracks provided by the ledges of guideway duct <NUM> edging the longitudinally extending slot. This allows, by a tipping movement of door member <NUM>, to transversely displace stop member <NUM> into the open position, where it is maintained by edge <NUM> of carriage <NUM> until first portion <NUM> of carriage <NUM> is fully received within guideway body <NUM>. After first portion <NUM> of carriage <NUM> has been inserted into guideway body <NUM> to be fully received within guideway body <NUM>, stop member <NUM> will, due to the restoring force caused by the sloped surface sections outlined above, autonomously return to the lock position. Thus, door member <NUM> is again securely locked to the guideway, or, in embodiments, to the draft shield, respectively. During the entire process, the operator does not need to manipulate stop member <NUM> by hand and thus can conveniently handle door member <NUM> with both hands.

Claim 1:
A guideway (<NUM>) configured for receiving and guiding a carriage (<NUM>), the guideway comprising a guideway body (<NUM>), the guideway body having a first longitudinal end and a second longitudinal end,
the guideway body (<NUM>) comprising a longitudinally extending clear channel (<NUM>) which is bordered by a wall of the guideway body (<NUM>),
wherein the longitudinally extending clear channel (<NUM>) opens at the first longitudinal end of the guideway body (<NUM>),
the guideway (<NUM>) further comprising a stop member (<NUM>) terminating the guideway at the first longitudinal end of the guideway body (<NUM>), the stop member comprising a crossbar (<NUM>) and two legs (<NUM>, <NUM>) extending from the crossbar, the crossbar (<NUM>) extending transverse to a longitudinal direction of the clear channel (<NUM>) and the legs (<NUM>, <NUM>) extending transverse to the longitudinal direction of the clear channel and transverse to the crossbar and the legs having a clearance between the two legs, whereby the stop member (<NUM>) forms a frame enclosing a window, wherein further the stop member has an opening on an edge of the window transversely opposite the crossbar (<NUM>), thus defining an open side of the stop member,
wherein the stop member (<NUM>) is displaceable on the guideway body (<NUM>) perpendicular to the crossbar (<NUM>) and transversely relative to the guideway body (<NUM>), between at least two transverse positions, wherein in at least one of the at least two transverse positions the crossbar at least partially overlaps with the clear channel of the guideway body, and in at least a second of the at least two transverse positions the window of the stop member at least partially overlaps with the clear channel of the guideway body.