Patent Description:
Such machines are known e.g. from document <CIT> that discloses a similar packaging machine with an unwind station base configured to support the web of packaging material; a scoring blade configured to selectively score the web; a conveyor assembly including a first and second set of conveyors with different advancing speeds that cause the wrapper to break apart from the web at the break line; and an elevator configured to lift the package vertically into engagement with the wrapper.

Rolls of product, for example rolls of household tissue, toilet paper or paper towels, typically need to be packaged for distribution and commercial sale. While rolls of products are sometimes individually wrapped, multiple rolls can be organized into bundles and packaged together. These bundles can be arranged in boxes, crates, bags or other containers, or they can be wrapped in a packaging material, such as paper or plastic.

Packaging machines for rolls of product can be configured to form a wrapper for packaging individual rolls or bundles from a web (i.e., a large sheet) of packaging material, which is often stored in a web roll. To form the wrapper, the web is drawn from the roll at an unwinding station before being cut to size based on the desired wrapper dimensions. The wrapper can then be separated from the web and transported to a wrapping station where the rolls or bundle of rolls will be wrapped in the wrapper.

To form the wrapper, packaging machines can utilize a shearing conveyor system. After being unwound from the roll, the web of packaging material may be scored to form a break line before moving onto a conveyor assembly that advances the web towards the wrapping station. The conveyor system may be configured to create a shearing force that breaks the web at the break line to form the wrapper. The wrapper may continue along the conveyor system until it is wrapped around a package at a wrapping station.

Packaging machines such as these may be configured to form different size wrappers to package products of various dimensions by scoring the web at different intervals. The size of the wrapper may be increased by scoring the web less frequently, thereby leaving larger gaps between break lines to from longer wrappers. Shorter wrappers for smaller products may be produced by scoring the web more frequently to leave smaller gaps between subsequent break lines. Since the smaller wrappers are shorter, they will need to travel a greater longitudinal distance on the conveyor system after being separated from the web than the larger, longer wrappers need to travel. This increased transport distance may increase in the instances of errors (for example, misalignment, skewing, or other imperfections), resulting in packaging rejections.

The present disclosure relates to an adjustable packaging machine including a sliding conveyor assembly that moves relative to the wrapping station. The conveyor assembly may be moved towards or away from the wrapping station to adjust the travel distance for a wrapper from the shear point to the elevator on the wrapping assembly based on the size of the wrapper and/or the product to be wrapped. By doing so, the total travel distance of the wrapper may be kept to a minimum, regardless of the size of the wrapper.

Embodiments of a packaging machine may be configured to form a wrapper from a web of packaging material and secure the wrapper to a package. The packaging machine may include an unwind station base configured to support the web of packaging material, a wrapping station frame spaced apart from the unwind station base, a carriage slidably mounted on the unwind station base, and a scoring blade configured to selectively score the web to form a break line extending between opposite lateral sides of the web. A conveyor assembly may be secured to the carriage and can extend from the unwind station base to the wrapping station frame. The conveyor assembly may include a first set of conveyors configured to advance the web towards the wrapping station frame at a first speed and a second set of conveyors configured to advance the web towards the wrapping station frame at a second speed that is greater than the first speed, wherein the difference in conveyor speeds causes the wrapper to break apart from the web at the break line. The packaging machine may additionally include an elevator secured to the wrapping station frame and configured to lift the package vertically into engagement with the wrapper. The carriage may be configured to selectively slide in a longitudinal direction relative to the wrapping station frame to adjust a travel distance of the wrapper to the elevator.

Embodiments of an unwind station may be configured to form a wrapper from a web roll and supply the wrapper to a wrapping station. The unwind station may include a base configured to rotatably support the web roll, a carriage configured to selectively slide in a longitudinal direction on the base, the carriage including a feed roller configured to unwind the web from the web roll, and a rotating blade configured to periodically score the web to form a break line extending between opposite lateral sides of the web. The unwind station may further include a first conveyor arm and a second conveyor arm that may project longitudinally outward from the carriage, and the first conveyor arm and the second conveyor arm may each include a low-speed conveyor configured to transport the web to a high-speed conveyor. The high-speed conveyor may be configured to separate the wrapper from the web as the break line passes a shear point between the low-speed conveyors and the high-speed conveyors.

Various other features, objects, and advantages will be made apparent from the following description taken together with the drawings.

In the present description, certain terms have been used for brevity, clarity and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes only and are intended to be broadly construed. The different methods and assemblies described herein may be used alone.

Unless otherwise specified or limited, the phrases "at least one of A, B, and C," "one or more of A, B, and C," and the like, are meant to indicate A, or B, or C, or any combination of A, B, and/or C, including combinations with multiple instances of A, B, and/or C. Likewise, unless otherwise specified or limited, the terms "mounted," "connected," "linked," "supported," and "coupled" and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, unless otherwise specified or limited, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings.

As used herein, unless otherwise limited or defined, discussion of particular directions is provided by example only, with regard to particular embodiments or relevant illustrations. For example, discussion of "top," "front," "back," "left" or "right" features is generally intended as a description only of the orientation of such features relative to a reference frame of a particular example or illustration. Correspondingly, for example, a "top" feature may sometimes be disposed below a "bottom" feature (and so on), in some arrangements or embodiments. Additionally, use of the words "first," "second", "third," etc. is not intended to connote priority or importance, but merely to distinguish one of several similar elements or machines from another.

Referring now to the figures, <FIG> illustrate an embodiment of an adjustable packaging machine <NUM> configured to form wrappers <NUM> for packages <NUM> (such as a product roll or a bundle of product rolls) of various different sizes. The packaging machine <NUM> may include an unwind station <NUM> configured to form a wrapper <NUM> from a web roll <NUM> and a wrapping station <NUM> configured to apply the wrapper <NUM> to a package <NUM>. The unwind station <NUM> may include a base <NUM> configured to rotatably support the web roll <NUM> and a sliding carriage <NUM> mounted on the upper end of the base <NUM>. A conveyor assembly <NUM> including a set of high-speed conveyors and low-speed conveyors mounted on left and right conveyor arms <NUM>, <NUM> may be coupled to the carriage <NUM> and extend in a longitudinal direction to a frame <NUM> of the wrapping station <NUM>. The conveyor assembly <NUM> is configured to break a wrapper <NUM> away from the web <NUM> and transport the wrapper <NUM> into the wrapping station <NUM>. To control the size of the wrapper, a user may adjust the longitudinal positions of the carriage <NUM> and the conveyor assembly <NUM> relative to an elevator <NUM> secured to the wrapping station frame <NUM> by sliding the carriage <NUM> and the conveyor assembly <NUM> longitudinally on their respective supports.

The packaging machine <NUM> includes elevator <NUM> secured to the wrapping station frame <NUM> below the conveyor assembly <NUM>. The elevator <NUM> receives the package <NUM> prior to wrapping. Once the wrapper <NUM> is moved into a position above the elevator <NUM>, the elevator <NUM> can lift the package <NUM> upwardly, pressing it into the wrapper <NUM>. The elevator <NUM> may continue to push the package <NUM> and wrapper <NUM> upwardly as guides <NUM> on the wrapping station frame <NUM> press the wrapper <NUM> onto the sides of the package <NUM>. Additional packaging machinery (not shown) may then be used to fully enclose the package <NUM> in the wrapper.

Having generally described features of a packaging machine <NUM>, the details of its components and their structure and features will now be discussed. Referring to <FIG>, the base <NUM> of the unwind station <NUM> may include support rollers <NUM> configured to rotatably support the web roll <NUM> (see <FIG> and <FIG>). The support rollers <NUM> may be positioned proximate a lower end of the unwind station base <NUM> and can extend between opposite lateral sides thereof. The support rollers <NUM> may be linked by a drive belt and such that they may be simultaneously rotated by a motor <NUM>. This may be useful, for example, in order to unroll the web <NUM> of packaging material from the web roll <NUM> when it is received on the unwind station <NUM>. Some embodiments of an unwind station may include a differently configured web roll support arrangement. For example, a web roll may be mounted on a single roller or spool that extends through the center of the web roll. Additionally or alternatively, some embodiments may be configured with at least one unpowered support roller configured to rotate freely as the web is drawn from a web roll.

The carriage <NUM> may include lateral side panels <NUM> linked by transverse structural members and can be slidably received on rails <NUM> that extend longitudinally along opposite lateral side of the base <NUM> of the unwind station <NUM>. In some embodiments, sliding movement of the carriage <NUM> may be controlled by a ball screw actuator <NUM>. For example, threaded rods <NUM>, which extend along the lateral sides of the base <NUM> perpendicular to the rails <NUM>, are configured to be engaged by positioning members <NUM> extending from the side panels <NUM> of the carriage <NUM>. When the threaded rods <NUM> are rotated, threaded engagement between the threaded rods <NUM> and positioning members <NUM> causes the carriage <NUM> to slide along the rails <NUM>, moving longitudinally relative to the base <NUM>. In the illustrated embodiments, the threaded rods <NUM> may be operatively linked to each other by a shaft <NUM> that extends laterally across the carriage <NUM>. This may be useful, for example, so that both of the threaded rods <NUM> can be simultaneously driven by one motor <NUM>.

Some embodiments of a packaging machine may include a different actuation system for moving the carriage. For example, the base of an unwind station may include threaded rods that are operatively linked by a different linkage configuration, while another embodiment may include independently driven threaded rods. Additionally or alternatively, a different type of electro-mechanical, hydraulic, or pneumatic linear actuator may be configured to control longitudinal movement of the carriage.

To draw the web <NUM> of packaging material from the web roll <NUM> and towards the conveyor assemblies <NUM>, <NUM>, the carriage <NUM> may include feed rollers <NUM> that extend between the opposing lateral side panels <NUM> of the carriage <NUM>. In some embodiments, the feed rollers may be textured to grip the web <NUM>, while other embodiments may include feed rollers without any specialized texture. Additionally or alternatively, a packaging machine may include at least one feed roller that is position on the base of the unwind station, the conveyor assembly, and/or any other part of the packaging machine.

Additionally or alternatively, the carriage <NUM> may include a scoring blade <NUM> configured to score the web <NUM> as it moves across the carriage to the conveyor assemblies <NUM>, <NUM>. The illustrated scoring blade <NUM>, for example, extends between opposite lateral sides of the carriage <NUM> and is configured to be rotated by a motor <NUM>. As the scoring blade <NUM> rotates, an edge of the blade <NUM> engages the top surface of the web <NUM> and presses it against a cutting surface <NUM> positioned below the web <NUM> (See, e.g., <FIG>). As the web <NUM> is pressed against the cutting surface <NUM>, the scoring blade <NUM> may be configured to form a grove and/or a series of perforations across the web <NUM> without cutting it, thereby forming break line (i.e., a weak point) in the packaging material extending across the web <NUM>. In the illustrated embodiments, the scoring blade <NUM> is configured to form a break line that extends laterally across the web <NUM> such that the break line is perpendicular to the longitudinal direction of travel of the web <NUM>. Other embodiments, however, may be configured to form a break line that may be angled and/or curved. Additionally or alternatively, some embodiments of a packaging machine may be configured with a different mechanism for scoring the packaging material web.

Embodiments of a packaging machine may include a conveyor assembly that links the unwind station to the wrapping station. In the illustrated embodiments, for example, the conveyor assembly <NUM> may include a left conveyor arm <NUM> and a right conveyor arm <NUM> that are each configured to be connected to the carriage <NUM> and supported on the frame <NUM> of the wrapping station <NUM> by a sliding support <NUM> (see, e.g., <FIG>). Each of the conveyor arms <NUM>, <NUM> includes a generally planar arm body <NUM> that extends from a back end <NUM> to a front end <NUM>. As shown in <FIG>, a notch <NUM> formed in the back end <NUM> of the arm body <NUM> is configured to receive a positioning bar <NUM> that extends across the carriage <NUM>, and a retention plate <NUM> can be secured to the arm body <NUM> to retain the positioning bar <NUM> in the notch <NUM>, thereby fixing the longitudinal position of the conveyor arm <NUM>, <NUM> relative to the carriage <NUM>.

When the conveyor arms <NUM>, <NUM> are connected to the carriage <NUM>, an interior surface <NUM> of the arm bodies <NUM> faces laterally inward towards the opposing conveyor arm <NUM>, <NUM>, and an exterior surface <NUM> of the arm bodies <NUM> faces laterally outward. As illustrated in <FIG>, one of the low-speed conveyors <NUM> and one of the high-speed conveyors <NUM> may be positioned on the interior surface <NUM> of each of the conveyor arms <NUM>, <NUM>. The low-speed conveyors <NUM> may include a lower belt <NUM> and an upper belt <NUM> that are configured to make contact with each other in order to grip the lateral edge of the web <NUM> between the belts <NUM>, <NUM>. The lower and upper belts <NUM>, <NUM> are driven by geared drive pulleys <NUM> that are meshed with each other so that the lower and upper belts <NUM>, <NUM> run in the same longitudinal direction and at the same speed. Additionally or alternatively, some embodiments of a conveyor assembly may be configured so that the low-speed conveyors on the left and right conveyor arms are operatively linked so that they run at the same speed. As illustrated in <FIG>, for example, the left conveyor arm <NUM> and the right conveyor arm <NUM> are in lateral alignment so that shaft <NUM> can extend between two corresponding geared drive pulleys <NUM>, linking the low-speed conveyors <NUM>. This may be useful, for example, so that a single motor can be used to drive the low-speed conveyors on the left and right conveyor arms <NUM>, <NUM>. Some embodiments, however, may include low-speed conveyors that are linked by a different linkage assembly, and/or the low-speed conveyors may be separately driven so that their speeds are independently controllable.

The high-speed conveyor <NUM> on each conveyor arm <NUM>, <NUM> includes a lower belt <NUM> and an upper belt <NUM> configured to run in the same direction and grip the lateral edge of the web <NUM>. The belts <NUM>, <NUM> of the high-speed conveyors <NUM> are driven by drive pulleys <NUM> that are linked to each other by a drive belt <NUM> arranged on the exterior surface <NUM> of the arm bodies <NUM>. The drive belt <NUM> additionally connects the lower and upper belts <NUM>, <NUM> to corresponding motors <NUM> configured to independently power the each of the high-speed conveyors <NUM>. This may be useful, for example, in order in independently control the speed of each of the high-speed conveyors <NUM>. Some embodiments, however, may be configured with high-speed conveyors that are not independently controlled.

The conveyor sets <NUM>, <NUM> may be configured to make contact with and convey the web <NUM> along the full length of the conveyor arms <NUM>, <NUM>. The low-speed conveyors <NUM> begin proximate the back end <NUM> of each arm body <NUM> and are configured to convey the web <NUM> to an interchange between the low-speed conveyors <NUM> and the high-speed conveyors <NUM>. The high-speed conveyors <NUM> begin at the interchange and end proximate the front end <NUM> of the arm bodies <NUM>. At the interchange, the ends of the low-speed belts <NUM>, <NUM> and the ends of the high-speed belts <NUM>, <NUM> are offset from each other such that there is a gap between the upper low-speed belt <NUM> and the upper high-speed belt <NUM> and the lower low-speed belt <NUM> overlaps with the upper high-speed belt <NUM>. This interchange configuration may be useful, for example, to provide a smooth transition between the low-speed conveyors <NUM> and the high-speed conveyors <NUM>. Additionally, the interchange may provide a shear point <NUM> where the wrapper <NUM> may be torn away from the web <NUM> as the break line passes through the interchange.

As previously mentioned, the left and right conveyor arms may be slidably supported on the wrapping station frame. For example, as illustrated in <FIG> and <FIG>, the frame <NUM> of the wrapping station <NUM> may include sliding supports <NUM> that are configured to slidably receive rails <NUM> that extend along at least one of the interior surface <NUM> and the exterior surface <NUM> of the conveyor arms <NUM>, <NUM>. The sliding interface between the conveyor arms <NUM>, <NUM> and the sliding supports allows the conveyor arms <NUM>, <NUM> to move relative to the wrapping station <NUM> along a longitudinal direction with the carriage <NUM>.

In some embodiments, the sliding supports may additionally allow for lateral movement of the conveyor arms. For example, as illustrated in <FIG>, each of the sliding supports <NUM> is slidably received on rails <NUM> that extend laterally between opposite sides of the frame <NUM> of the wrapping station <NUM>. A linear actuator <NUM> may be operatively connected to each sliding supports <NUM> and can be configured to control lateral movement of the sliding supports <NUM> along the rails <NUM>. Because the connection between the conveyor arms <NUM>, <NUM> and the positioning bar <NUM> of the carriage <NUM> allows for lateral movement of the conveyor arms <NUM>, <NUM>, the linear actuators <NUM> may be used to adjust the lateral positions of the conveyor arms <NUM>, <NUM>. This may be useful, for example, in order to change the distance between the left conveyor arm <NUM> and the right conveyor arm <NUM> based on the width of the web <NUM>, or to align a centerline of the conveyor assembly <NUM> with a lateral midpoint of the elevator <NUM>.

Some embodiments of a packaging machine may include a conveyor assembly with additional conveyors. In the illustrated embodiments, for example, the conveyor assembly <NUM> may include a central conveyor arm <NUM> configured to be positioned between the left conveyor arm <NUM> and the right conveyor arm <NUM>. As illustrated in <FIG> and <FIG>, the central conveyor arm <NUM> may be slidably received on a support member <NUM> that extends from the frame <NUM> of the wrapping station <NUM> and is positioned in alignment with the elevator <NUM>. The body of the central conveyor arm <NUM> may include a notch <NUM> configured to receive the positioning bar <NUM> of the carriage <NUM>, and a retention plate <NUM> can be configured to retain the positioning bar <NUM> in the notch <NUM>, thereby linking longitudinal sliding movement of the central conveyor arm <NUM> to that of the carriage <NUM>. In the illustrated embodiments, and referring specifically to <FIG>, the central conveyor arm <NUM> may include a low-speed conveyor <NUM> with a single belt <NUM> configured to engage the lower surface of the web <NUM>. The low-speed conveyor belt <NUM> may by positioned so that it is substantially in alignment with the lower belts <NUM> of the low-speed conveyors <NUM> on the left and right conveyor arms <NUM>, <NUM>. A drive pully <NUM> configured to drive the low-speed conveyor belt <NUM> may be engaged by the shaft <NUM> so that the low-speed conveyor belt <NUM> moves at the same speed as the low-speed conveyors <NUM> on the left and right conveyor arms <NUM>, <NUM>. In some embodiments, however, the packaging machine may include an additional motor configured to independently drive the central conveyor.

Embodiments of the adjustable packaging machine <NUM> may be configured to continuously produce wrappers <NUM> to be secured to products. As the web <NUM> of packaging material is advanced through the carriage <NUM>, the scoring blade is continuously rotated by the motor <NUM> and a break line is formed across the web <NUM> each time the cutting edge of the scoring blade <NUM> engages the web <NUM>. The web <NUM> is then drawn into the conveyor assembly <NUM> as the low-speed conveyors <NUM> on the left conveyor arm <NUM> and the right conveyor arm <NUM> respectively grip the left and right edges of the web <NUM>, transporting the web <NUM> away from the unwind station <NUM> and towards the wrapping station <NUM>. The central conveyor <NUM> may support the material in the center of the web <NUM> and maintain its speed as the web <NUM> travels along the conveyor assembly <NUM>. Guides <NUM> positioned above and below the web <NUM> on the frame <NUM> of the wrapping station <NUM> may be configured to restrict vertical movement of the web <NUM> prior to activation of the elevator <NUM>.

As the web <NUM> is passed from the low-speed conveyors <NUM> and the high-speed conveyors <NUM>, the elevated speed of the high-speed conveyors <NUM> creates a shearing force localized proximate the shear point <NUM> that pulls the web <NUM> towards the front end <NUM> of the conveyor arms <NUM>, <NUM>. The strength of the shearing force, which may be based on at least one of the speed of the low-speed conveyors <NUM>, the speed of the high-speed conveyors <NUM>, the gripping force used to grip the web <NUM> with the conveyors <NUM>, <NUM>, and any other factors, can be selected so that unscored packaging material is not damaged by the shearing force as the web passes through the interchange. As the break line formed by the scoring blade <NUM> passes the shear point <NUM>, however, the shearing force breaks the packaging material at the break line, thereby separating a wrapper <NUM> from the web <NUM>. Subsequent wrappers are formed each time a break line in the web <NUM> passes through the shear point <NUM> at the interchange.

Embodiments of the packaging machine <NUM> may be adjusted to accommodate and produce wrappers <NUM> having different sizes by adjusting the longitudinal position of the conveyor assembly <NUM> relative to the elevator <NUM> and/or controlling the rate of rotation of the scoring blade <NUM>. <FIG> and <FIG> illustrate embodiments of the packaging machine <NUM> in a fully retracted configuration in which the carriage <NUM> is positioned at the maximum longitudinal distance from the frame <NUM> of the wrapping station <NUM>. When the packaging machine <NUM> is in the fully retracted configuration, the longitudinal distance "D" between the shear point <NUM> and the longitudinal midpoint <NUM> of the elevator <NUM> (both denoted by dashed lines in <FIG> and <FIG>) is maximized. This may be useful, for example, in order to produce wrappers having long lateral lengths, which is limited by the distance "D" between the shear point <NUM> and elevator <NUM>.

When packaging smaller products, however, it may be desirable to use a wrapper having a shorter longitudinal length. In such a scenario, the rotational speed of the scoring blade <NUM> may be increased in order to increase the frequency of blade-web contact, thereby creating break lines which are closer together. If the packaging machine is left in the fully retracted configuration, each of these smaller wrappers will need to travel a greater distance from the shear point to the elevator than the larger wrappers, which may increase the risk of wrapper misalignment and other errors. Some embodiments of a packaging machine may include optical sensors (not shown) that monitor a leading edge of a wrapper as it travels to the elevator. If skewing is detected, the rate of the high-speed conveyor <NUM> on one of the left or right conveyor arms <NUM>, <NUM> may be increased or decreased relative to the other high-speed conveyor <NUM> in order to realign the wrapper and correct the error.

In the disclosed embodiments, the risk of such errors occurring may be reduced by moving the carriage <NUM> and the conveyor assembly <NUM> in towards the wrapping station <NUM>. As the actuator <NUM> slides the carriage <NUM> and the conveyor assembly <NUM> towards the wrapping station <NUM> the distance between the shear point <NUM> and the elevator <NUM>, is reduced. For example, <FIG> an embodiment of the packaging machine <NUM> is a fully extended configuration in which the carriage <NUM> is positioned at the minimum longitudinal distance from the frame <NUM> of the wrapping station <NUM>. With the packaging machine in the fully extended configuration, the longitudinal distance "D" between the shear point <NUM> and the longitudinal midpoint <NUM> of the elevator <NUM> and therefore the travel distance of the wrappers <NUM>, is minimized. This may be useful, for example, in order to produce wrappers <NUM> having shorter longitudinal lengths without changing the footprint of the packaging machine <NUM>. Embodiments the packaging machine <NUM> can be adjusted to produce wrappers having longitudinal dimensions which are different than the illustrated wrappers by moving the carriage <NUM> and conveyor assembly <NUM> to longitudinal positions between their fully retracted and fully extended positions.

Claim 1:
A packaging machine configured to form a wrapper (<NUM>) from a web (<NUM>) of packaging material and secure the wrapper (<NUM>) to a package (<NUM>), the packaging machine (<NUM>) comprising:
an unwind station base (<NUM>) configured to support the web (<NUM>) of packaging material;
a wrapping station frame (<NUM>) spaced apart from the unwind station base (<NUM>);
a scoring blade (<NUM>) configured to selectively score the web (<NUM>) to form a break line extending between opposite lateral sides of the web (<NUM>);
a conveyor assembly (<NUM>) extending from the unwind station base (<NUM>) to the wrapping station frame (<NUM>), the conveyor assembly (<NUM>) including a first set of conveyors configured to advance the web (<NUM>) towards the wrapping station frame (<NUM>) at a first speed and a second set of conveyors configured to advance the web (<NUM>) towards the wrapping station frame (<NUM>) at a second speed that is greater than the first speed, wherein the difference in conveyor speeds causes the wrapper (<NUM>) to break apart from the web (<NUM>) at the break line;
an elevator (<NUM>) secured to the wrapping station frame (<NUM>) and configured to lift the package (<NUM>) vertically into engagement with the wrapper (<NUM>);
characterised in that it further comprises a carriage (<NUM>) slidably mounted on the unwind station base (<NUM>), and on which the conveyor assembly (<NUM>) is secured;
wherein the carriage (<NUM>) is configured to selectively slide in a longitudinal direction relative to the wrapping station frame (<NUM>) to adjust a travel distance of the wrapper (<NUM>) to the elevator (<NUM>).