Patent Application
20120286087
Various types of printers utilize a spindle to support the media being fed into the printer. The media used in these printers is rolled onto a cardboard core that is then slipped over the spindle to secure the media in place for use by the printer.
A predetermined amount of tension on the sheet of print media extending between the roll of media and the printer is desirable. However, the spindle may be mechanically attached to a braking system in the printer, and braking of the spindle may cause an undesirable advancement of the media. This may result in a corresponding loss of tension. Consequently, to prevent any undesirable effects in advancing the media through the printer, a pneumatic device may be used to prevent loss of roll traction by pressing various parts of the spindle firmly against the interior of the roll.
The diameter of media roll that a pneumatic spindle accommodates may be limited by the diameter of the spindle. This is because the pneumatic features of the spindle, when the spindle is pressurized, may only be pushed out from the spindle a limited distance. This distance may be insufficient to engage some larger diameters of media rolls available on the market. Therefore, a printer spindle may limit the types of media that may be used on that printer simply because of the incompatibility of the media roll and the spindle.
The accompanying drawings illustrate various embodiments of the principles described herein and are a part of the specification. The illustrated embodiments are merely examples and do not limit the scope of the claims.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.
As noted above, appropriate tension in the advancing print media, between the media supply roll and the printer, will prevent skewing and wrinkling of the media and thereby will produce a better quality product. To this end, a pneumatic spindle may be used to properly secure the roll of media to the spindle. A pneumatic spindle is a spindle having a number of portions that, when the interior of the spindle is pressurized, protrude out of the spindle and provide friction between the spindle and the cardboard interior of the media roll.
However, during operation, users of a printer may need to employ different types, thicknesses, and sizes of media in order to produce a desired product. Consequently, the media roll used in a printer will have to be changed when a different type of media is needed.
Each new media roll to be used is placed on the spindle. However, various types of media that may be purchased on the market may have cardboard cores of different diameters. If the diameter of a media roll to be used is larger than can be spanned by the pneumatic spindle when pressurized, the spindle cannot maintain the desired tension in the media web between the roll and the printer. For example, a three inch pneumatic printing spindle may not be able to properly handle a media roll having a 6 inch diameter core. In this case, the pneumatic feature of the spindle may not properly hold the roll of media and thereby may allow undesirable slack in the advancing media.
In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present systems and methods. It will be apparent, however, to one skilled in the art that the present apparatus, systems and methods may be practiced without these specific details. Reference in the specification to “an example” or similar language means that a particular feature, structure, or characteristic described in connection that example is included in at least that one example, but not necessarily in others.
As used in the present specification and the appended claims, the term “pneumatic spindle” or “spindle” is meant to be understood broadly as any spindle capable of being inflated by some gas so that various parts of the spindle extend out to, and make contact with, the interior surface of a media roll. Pressurization of the spindle may be accomplished by forcing a gas into an inner core of the spindle thereby causing some portions of the spindle to jut or protrude out. Those portions of the spindle may be biased to retract into the spindle when the pressurized gas is note applied.
Other examples of the present spindle may further include a hydraulic system instead of a pneumatic system. The hydraulic system may pressurize the interior of the spindle by forcing a liquid instead of a gas into the interior of the spindle thereby creating a similar effect to that of the pneumatically activated spindle. Still further, another example may comprise a gear system which, when engaged, causes a number of grips to protrude out of the spindle and thereby contact the interior surface of a media roll. However, for purposes of simplicity, the following examples will be described in terms of using a pneumatic spindle. But, it will be understood that a spindle using some other mechanism than pneumatics to extend portions that contact the interior surface of a media roll may be used in the following examples and in the principles described herein.
Turning to
As discussed earlier, the spindle (105) is a pneumatic spindle. The pneumatic spindle (105) allows for air to be introduced into the interior of the spindle (105) so that a number of grips (115) are forced outward radially from the spindle (105). Usually, these grips (115) are made out of rubber or some other resilient friction-generating material. These grips (115) are meant to come into contact with the interior of a media roll placed on the spindle (105). However, as discussed earlier, these grips (115) may not extend far enough out from the outer surface of the spindle (105) to contact the internal surface of any media roll having a significantly larger diameter than that of the spindle (105).
In one example, any number of grips (115) may be incorporated into the spindle (105). For the purposes of simplicity in illustration, in the present example, the pneumatic spindle (105) may include three grips (115) running the length of the spindle (105) which extend radially outward from the spindle (105). These grips (115) may be placed parallel to the longitudinal axis of the spindle (105), each grip (115) being placed at a fraction of the total radius of the spindle (105). Therefore, in the present example, the three grips (115) may be arranged to lie lengthwise along the spindle at 0° (or 360°), 120°, and 240° angles. In further examples, the spindle may have any number of grips (115) arranged lengthwise and radially along the spindle (105).
The spindle (105) may also include a transmission gear (120) on a first end of the spindle (105) that may be used to receive a rotational force from a motor located in the printer into which the spindle (105) is to be placed. The gear (120) may be used by the printer to, when necessary, either prevent the spindle (105) from turning or permitting the spindle (105) to advance the media in an appropriate manner. Specifically, the gear (120) may be used to produce the proper tension between the media roll and the printer, thereby preventing skewing or wrinkling of the media as it advances through the printer.
As mentioned, the system (100) further includes a number of adapters (110). Specific details of the adapters (110) will now be discussed in connection with
The core (125) may be made of extruded aluminum or any other rigid and durable material, including, but not limited to, metals, alloys, plastics, ceramics and composites. The core (125) includes a number of outer channels (170) located and running lengthwise along the exterior wall of the core (125). Each outer channel (170) is generally in a T-shaped configuration such that a rib (145) may fit without sliding out radially from the channel (170). Additionally, the core (125) includes a hole defined in the cylindrical core (125) through which the pneumatic spindle (
The cylindrical core (125) further includes a number of inner channels (175) located and running lengthwise along the interior wall of the core (125). Similar to the T-shaped channels (170) on the exterior surface of the cylindrical core (125), each inner channel (175) may be generally in a T-shaped configuration such that a pusher base (130) may fit therein without sliding out of the channel (175) radially and into the center of the core (125).
Additionally, the core (125) may have a number of pusher pin channels (180) through which corresponding pusher pins (135) may freely slide. In one example, the core (125) may include three pusher pin channels (180) running from each outer channel (170) to a corresponding and radially located inner channel (175).
Still further, the core (125) may include a number of cover screw holes (185) into which the cover screws (165) may be screwed so as to secure the cover plate (150) to the core (125). Again, any number of cover screw holes (185) may be formed along the outer edges of the core (125) so as to secure the cover plates (150) to the core (125) with a secure fit.
As briefly discussed above, a pusher base (130) may fit into each inner channel (175). Each pusher base (130) may be in radial communication with a number of pusher pins (135). In one example, the pusher pins may be coupled to the pusher base (130) by gluing, welding, or other ways of fastening the pins (135) to the pusher base (130). In yet another example, the pusher pins (135) may be allowed to move freely in the pusher pin channels (180) without being coupled to the pusher base (130).
The pusher pins (135) are also in radial communication with a rib (145). Again, in one example, the pusher pins may be coupled to the rib (145) by gluing, welding, or other ways of fastening the pins (135) to the rib (145). In yet another example, the pusher pins (135) may be allowed to move freely in the pusher pin channels (180) without being coupled to the rib (145).
As a result of this layout within the core, radial movement of the pusher base (130) will result in radial movement of the pusher pins (135) which will in turn result in radial and outward movement of the rib (145). Therefore, when the adapter (110) is coupled to the pneumatic spindle (
The adapter (110) may further include a number of springs (140) located with the outer channel (170). In one example, a number of springs (140) may be placed between the interior surface of the outer channel (170) and the rib (145). The springs (140) may be biased to either force the rib (145) outward radially from the core (125) or be biased to force the rib (145) inward radially towards the interior of the core (125).
In another example, a number of springs may be placed between the interior wall of the inner channel (175) and the pusher base (130). Again, these springs (140) may be biased to either force the pusher base (130) outward radially from the center of the core (125) or be biased to force the pusher base (130) inward radially towards the interior of the core (125).
The adapter (110) may also comprise a number of cover plates (150). Similar to the core (125), the cover plates (150) may also be made of extruded aluminum or any other rigid and durable material. The cover plates (150) prevent the pusher bases (130), pusher pins (135), and ribs (145) from falling out of their respective channels (170, 175, 180). The plates (150) may be secured to the core (125) by a number of cover screws (165). Once in place, the cover plates (150) may also add support or structure to the adapter (110).
Each cover plate (150) may further support a knurled head screw (160) and a fixing cover (155). The fixing cover (155) may also be attached to the cover plate (150) or the core (125) via a number of cover screws (165). In one example, the same cover screws (165) used to secure the cover plate (150) to the core (125) may also be used to secure the fixing cover to the cover plate (150) and core (125). Again, any number of cover screws (165) may be used to secure the fixing cover (155) to the core (125). A corresponding number of cover screw holes (185) are formed in the core to receive the cover screws (165). The fixing cover (155) further includes a retention tab (195) that retains a knurled-headed set screw (160) in position.
The cover plates (150) may have a setting tab (190) through which the knurled-headed set screw (160) may be passed. When the knurled-headed set screw (160) is in place, the fixing cover (155) may be coupled to the cover plate (150). Therefore, when the cover plate (150), knurled-headed set screw (160), and fixing cover (155) are secured in their places as described above, the top of the knurled head screw (160) may be accessed by a user through a hole defined in the retention tab (195). The user may then choose to secure the adaptor (110) to the spindle (105) by either screwing the knurled-headed set screw (160) down towards the spindle (105) using their fingers, or by screwing in the knurled-headed set screw with a screwdriver. In one example, the spindle (105) may include various dimples or holes defined in the surface into which the knurled-headed set screw (160) may be set. In a further example, the knurled-headed set screw (160) may be screwed down to the spindle (105) so that the bottom surface of the screw (160) abuts the spindle (105) thereby securing the adaptor (110) to the spindle (105).
Securing the adapter (110) to the spindle (105) assures that the adapter (110) will not rotate perpendicular to the longitudinal axis of the spindle (105). Additionally, securing the adapter (110) to the spindle (105) properly will prevent the adapter (110) from sliding parallel to the longitudinal axis of the spindle (105) when the spindle (105) is inserted into the media roll. Still further, securing the adapter (110) to the spindle (105) at the appropriate location assures that the individual grips (115) of the spindle (105) may come into contact with the pusher bases (130) of the adapter (110). Other fastening devices may be used to secure the adapter (110) to the spindle (105); these devices being either external or internal to the core (125).
In the example shown in
Still further any number of grips (115) may be included on the spindle (105) and, therefore, the adapter (110) may have a corresponding number of pusher bases (130), sets of pusher pins (135), and ribs (145). Various angular configurations of the pusher base (130), sets of pusher pins (135), and ribs (145) may be used depending on the configurations of the spindle (105) and its grips (115).
Once all of the adapters (
As briefly discussed earlier, various configurations of the present adapter (
Additionally, the number of adapters (
Still further the final diameters (d, D) of the adapters (
In conclusion, the specification and figures describe a spindle adapter (110). The adapter (110) allows a user to use a media roll on a spindle (105) with proper tensioning even though the internal diameter of the media roll is larger than the diameter of the spindle (105). This is accomplished by transferring the mechanical force from the grips (115) of the pneumatic spindle (105) to a pusher base (130) which in turn transfers that mechanical force to a number of pusher rods (135) which then transfers that mechanical force to a number of ribs (145). The ribs, then being further away from the spindle (105), may make contact with the interior surface of the media roll and prevent the media roll from slipping when in use with a printer. This spindle adapter may have a number of advantages, including: providing better traction between the spindle and media roll, less cost in replacement parts should a user require a larger diameter pneumatic spindle, and higher reliability due to the lack of any complex internal mechanisms that may break down.
The preceding description has been presented only to illustrate and describe embodiments and examples of the principles described. This description is not intended to be exhaustive or to limit these principles to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.
