(19)
(11)EP 1 962 145 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
12.04.2017 Bulletin 2017/15

(21)Application number: 08151608.0

(22)Date of filing:  19.02.2008
(51)Int. Cl.: 
G03G 15/00  (2006.01)

(54)

Acoustic dampening material for imaging drum

Akustisches Dämpfmaterial für Bildgebungstrommel

Matériau d'amortissement acoustique pour tambour d'imagerie


(84)Designated Contracting States:
DE FR GB

(30)Priority: 21.02.2007 US 708974

(43)Date of publication of application:
27.08.2008 Bulletin 2008/35

(73)Proprietor: Xerox Corporation
Rochester, New York 14644 (US)

(72)Inventors:
  • Hart, Steven C.
    Webster, NY 14580 (US)
  • Campbell, Pat C.
    Farmington, NY 14425 (US)

(74)Representative: Grünecker Patent- und Rechtsanwälte PartG mbB 
Leopoldstraße 4
80802 München
80802 München (DE)


(56)References cited: : 
DE-A1- 3 140 070
JP-A- 63 060 480
US-A1- 2006 099 010
JP-A- 8 146 637
JP-A- 2003 066 770
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    BACKGROUND



    [0001] Herein disclosed are embodiments generally relating to electrostatographic imaging members and assemblies comprising electrostatographic imaging members and acoustic dampening means. The acoustic dampening means provide excellent acoustic dampening of the resonance modes of imaging drums. More specifically, the embodiments disclose an acoustic dampening material employed in photoreceptor and/or dielectric receptor drums to substantially eliminate acoustic noise generated by drum image receivers in electrostatographic printing machines.

    [0002] The term electrostatographic is used to generally encompass the fields of electrophotography and / or ionography. Hereafter, the term "drum" and / or "electrostatographic drum" will refer to either type of imaging drum - i.e. both photoreceptor and ionographic imaging drums. Electrostatographic imaging members are well known in the art. The imaging members may be in the form of various configurations such as a flexible web type belt or cylindrical drum. The drums comprise a hollow cylindrical substrate and at least one electrostatographic coating. These drums are usually supported by a hub held in place at the end of each drum. The hub usually includes a flange extending into the interior of the drum. This flange is usually retained in place by an interference fit and/or an adhesive. An axle shaft through a hole in the center of each hub supports the hub and drum assembly. Electrostatographic imaging members may be electrophotographic members or electrographic (ionographic) members. It is well known that electrophotographic members comprise at least one photosensitive imaging layer and are imaged with the aid of activating radiation in image configuration. Similarly, electrographic imaging members comprise at least one dielectric layer upon which an electrostatic latent image is formed directly on the imaging surface by shaped electrodes, ion streams, styli and the like.

    [0003] A typical electrostatographic imaging process cycle involves forming an electrostatic latent image on the imaging surface, developing the electrostatic latent image to form a toner image, transferring the toner image to a receiving member and cleaning the imaging surface. Cleaning of the imaging surface of electrostatographic imaging members is often accomplished with a doctor type resilient cleaning blade that is rubbed against the imaging surface of the imaging members.

    [0004] When electrostatographic imaging members are cleaned by doctor type cleaning blades rubbing against the imaging surface to remove residual toner particles remaining on the imaging surface after toner image transfer to a receiving member, a high pitched ringing, squealing, squeaking, or howling sound can be created which is so intense that it is intolerable for machine operators. This is especially noted in drum type imaging members comprising a hollow cylindrical substrate. The sound apparently is caused by a "stick-slip" cycling phenomenon during which the cleaning blade initially "sticks" to the imaging surface and is carried in a downstream direction by the moving imaging surface to a point where resilience of the imaging blade forces the tucked blade to slip and slide back upstream where it again sticks to the photoreceptor and is carried downstream with the imaging surface until blade resilience again causes the blade to flip back to its original position. The upstream flipping motion kicks residual toner particles forward. The stick-slip phenomenon is somewhat analogous to the use of a push broom for cleaning floors where the push broom is most effective for cleaning when it is pushed a short distance and then tapped on the floor with the cycle being repeated again and again. This stick-slip phenomenon is important for effective removal of residual untransferred toner particles from an imaging surface and for prevention of undesirable toner film or toner comets from forming on the imaging surface during cleaning.

    [0005] An adhesive relationship between the cleaning blade and the imaging member surface appears to contribute to the creation of the howling sound. More specifically, the stick-slip effect occurs where there is a strong adhesive interaction between the cleaning blade and the imaging surface. The howling sound appears to be caused by resonant vibration of the drum induced by the stick-slip phenomenon. Other factors contributing to creation of the screaming or howling sound may include factors such as the construction of the imaging member, the blade contacting the imaging member, the type of blade holder construction, and the like. For example, a flimsy blade holder can contribute to the howling effect. Moreover, a thinner, shorter, stubbier cleaning blade tends to contribute the howling effect. Thin imaging member drums can also lead to the howling effect. The stick-slip phenomenon also depends on the lubricating effect of toner and/or carrier materials utilized. Moreover, ambient temperatures can contribute to the creation of howling. It appears that resonance is initiated at the point of contact between the cleaning blade and the imaging member. The creation of the screaming or howling sound might be analogous to rubbing a fingertip around the edge of a wine glass. The screaming or howling noise phenomenon is especially noticeable for cylindrical photoreceptors having a hollow metal or plastic drum shaped substrate. Generally, where the imaging member is the cause of a howling sound, it will emit a ringing sound when tapped.

    [0006] Some methods used to reduce the noise include adding lubricants to the toner to reduce the frictional excitation (chatter or slip stick motion), which in turn reduces the excitation energy driving the acoustic resonance, internal "silencers" of various materials and configurations inserted into the interior cavity of the photoreceptor drum to absorb the sound energy and reduce the resonance amplitude, and increasing the wall thickness of the photoreceptor drum, which in turn increases the stiffness of the drum to raise resonant frequency and reduce amplitude of vibration for any given level of excitation. For example, U.S. Patent Nos. 7,155,143, 6,438,338, 5,669,045 and 5,960,236, as well as Japanese patent JP81466371, disclose internal "silencers." One alternative method for reducing the noise in photoreceptor drums is disclosed in Japanese Patent N. 63060480. However, these known methods suffer from drawbacks, such as poor fit in the drum, poor sound absorption and relatively high cost.

    [0007] Thus, there is a continuing need for improved systems and apparatuses which substantially reduce acoustic resonance and thus substantially eliminate acoustic noise caused by drum photoreceptors in xerographic printing machines.

    SUMMARY



    [0008] The above defined object is fulfilled by this invention, the scope of which is defined by the appended claims.

    [0009] According to embodiments illustrated herein, there is provided an electrostatographic imaging member assembly that includes acoustic dampening means that provide excellent dampening of the resonance modes of electrostatographic drums, and thus, substantially eliminate acoustic noise caused by electrostatographic drums.

    [0010] In particular, an embodiment provides an electrostatographic drum comprising a hollow cylindrical substrate, at least one imaging layer disposed on the hollow cylindrical substrate, and an acoustic dampening material at least partially applied to an interior surface of the hollow cylindrical substrate such that intimate contact is made between the acoustic dampening material and the interior surface of the hollow cylindrical substrate.

    [0011] Embodiments also provide an electrostatographic imaging member assembly comprising an electrostatographic drum, wherein the electrostatographic drum further comprises a hollow cylindrical substrate, at least one imaging layer disposed on the hollow cylindrical substrate, and an acoustic dampening material at least partially applied to an interior surface of the hollow cylindrical substrate such that intimate contact is made between the acoustic dampening material and the interior surface of the hollow cylindrical substrate, and a cleaning blade assembly, wherein the cleaning blade assembly further comprises a cleaning blade, and a blade holder adapted to support the cleaning blade.

    [0012] In a further embodiment the acoustic dampening material is selected from the group consisting of room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk, and mixtures thereof.

    [0013] Further embodiments provide a method for dampening acoustic resonance in an electrostatographic drum, comprising applying an acoustic dampening material to an electrostatographic drum, wherein the electrostatographic drum comprises a hollow cylindrical substrate, and at least one imaging layer, and wherein the acoustic dampening material is at least partially applied to an interior surface of the hollow cylindrical substrate, and curing the acoustic dampening material so that intimate contact is made between the acoustic dampening material and the interior surface of the hollow cylindrical substrate.

    [0014] In a further embodiment the acoustic dampening material is selected from the group consisting of room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk, and mixtures thereof.

    [0015] In a further embodiment from about 5 grams to about 400 grams of the acoustic dampening material is used.

    [0016] In a further embodiment the acoustic dampening material is applied in the form of one or more beads.

    [0017] In a further embodiment multiple beads of the acoustic dampening material are applied to the interior surface of the hollow cylindrical substrate.

    [0018] In a further embodiment multiple beads of the acoustic dampening material is applied to the interior surface of the hollow cylindrical substrate with each bead being applied about 100 mm in from each end of the hollow cylindrical substrate.

    [0019] In a further embodiment the acoustic dampening material is selected from the group consisting of room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk, and mixtures thereof.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0020] For a better understanding of the present invention, reference may be had to the accompanying figure.

    [0021] The Figure is a perspective view of an electrostatographic drum according to a comparative example of the present disclosure.

    DETAILED DESCRIPTION



    [0022] In the following description, it is understood that other embodiments may be utilized and structural and operational changes may be made without departure from the scope of the present embodiments disclosed herein.

    [0023] The present embodiments relate to the use of an acoustic dampening compound partially applied to and cured on the interior of an electrostatographic drum. The applied material provides excellent acoustic dampening of the resonance modes, and thus, substantially eliminates the problematic sounds that are often emitted from the xerographic printing machines. The acoustic dampening compound can, in embodiments, be a latex caulk or room temperature vulcanizing silicon rubber (RTV), and can be applied as a bead of the acoustic dampening compound. When cured, the material is in intimate contact with the inside of the drum and remains flexible. Intimate is defined herein as conforming to microscopic variations in the interior surface and providing a contact area of at least 90% or greater of the total interface surface. This method is a simple yet effective way to provide excellent acoustic dampening of the resonance modes and silencing the xerographic printing machines.

    [0024] Xerographic printers employing rigid electrostatographic drums often exhibit acoustic noise. This noise occurs because of the excitation of an acoustic resonant mode of the electrostatographic drum by the slip-stick motion of the cleaning blade. The resultant sounds have been classified by a variety of names describing the sounds to which they have resemblance, for example, "mooing", "grunting", squealing", and the like. Common approaches have encountered drawbacks of their own, such as poor fit in the drum, poor sound absorption and relatively high cost.

    [0025] The present embodiments disclose a method of application of an acoustic dampening material to the inside of the electrostatographic drum. Specifically, a bead of an acoustic dampening compound, such as RTV type silicone or latex caulk, is applied partially to the inside of the drum and allowed to cure. In addition, any other flexible material similar to RTV type silicone or latex caulk can be used with the present embodiments. Once cured, the acoustic dampening material is in intimate contact with the inside of the drum and remains flexible, which provides excellent acoustic dampening of the various resonance modes or sounds. The intimate contact ensures that the acoustic dampening material fits well along the interior of the drum and thoroughly covers all areas that would emit the various resonance modes.

    [0026] In comparison, previous "silencers" or "silencer inserts," for example, plastic slugs with C-shaped cross-sections and about 4 inches long) employed for the same purpose did not work well since the "silencers" did not make good intimate contact with the electrostatographic drum and were fairly rigid (hence not acoustically "lossy"). Because sound propagates well through hard rigid materials such as aluminum as well as through non-viscous liquids such as water, the selected acoustic dampening material needs to be flexible or, if a liquid, needs to be viscous or "sticky." Materials such as peanut butter, JELL-O, mayonnaise, RTV type silicone, and latex caulk are examples of lossy materials. Furthermore, the "silencers" are significantly more expensive than a bead or thin layer of RTV type silicone or caulk. For example, some silencers cost on the order of $0.20 each, and two or more are needed for each electrostatographic drum. It is estimated that about 20 grams or less of the acoustic dampening compound, for example, RTV type silicone, would be needed to perform the desired dampening function. As such, the present embodiments, using the acoustic dampening compound, is estimated to cost about $0.10 per drum. Thus, the present embodiments have shown to be more effective in dampening resonance modes of the electrostatographic drum as well as more cost-effective than previous methods.

    [0027] The dampening material needs to make very intimate contact so as to allow the sound waves to propagate into the lossy material. Compounds such as RTV type silicone, latex caulk, or high temperature vulcanizing silicone rubber (used in fuser rolls) make excellent contact and even chemically bond to the electrostatographic drum interior surface. This property provides excellent acoustic coupling between the drum substrate and the dampening material. In addition, the compounds used in the present embodiments are compatible with the imaging member material coating so as to not outgas or degrade the imaging member performance.

    [0028] In embodiments, there is provided an electrostatographic drum that performs without causing the undesired noises often emitted by the xerographic printing machines. As shown in the Figure, an electrostatographic imaging member assembly 5 is illustrated as comprising a hollow electrostatographic imaging drum 10 and a cleaning 7 blade assembly 15. The imaging drum 10 further comprises a hollow cylindrical substrate 20 and at least one electrophotographic imaging layer 25. The cylindrical substrate 20 may comprise any suitable material such as aluminum, nickel, non magnetic stainless steel, copper, metallic alloys of these materials, and plastic materials both of the thermo set and thermoplastic type and both with and without reinforcement such as carbon fiber (graphite), fiberglass, glass bead, etc , mixtures thereof, and the like. In the Figure, the cleaning blade assembly 15 is in contact with the outer imaging surface of the electrophotograhic imaging layer 25. The cleaning blade assembly 15 comprises a resilient elastomeric cleaning blade 30 supported by a relatively rigid blade holder 40. The cleaning blade holder 40 may be supported in any suitable manner, such as for example, a machine housing (not shown) which also provides support for the imaging drum 10. Along the interior of the imaging drum 10, in intimate contact with the inner side of the hollow cylindrical substrate 20, is a bead of an acoustic dampening compound 35. This compound may be RTV type silicone, latex caulk, High Temperature Vulcanizing Silicone rubber, or any similar flexible material, or mixtures thereof.

    [0029] In a comparative examples, a layer of acoustic dampening compound 35 has a thickness of from about 0.1 mm to about 6.0 mm. In other examples, the thickness is from about 0.5 mm to about 3.0 mm. In examples, the layer may have a length of from about 10 mm to about the entire length of the interior surface of the hollow cylindrical substrate. In further examples, the length of the layer may be extended to within about 5 mm of the end of the drum 10 on either end. In embodiments, one or more beads, two or more beads, or multiple beads may be used to provide acoustic dampening. Where multiple beads of the acoustic dampening material are used, the beads are applied to the interior surface of the hollow cylindrical substrate. In a particular embodiment, the multiple beads are applied to the interior surface of the hollow cylindrical substrate with each bead being applied about 100 mm in from each end of the hollow cylindrical substrate and optionally with one bead being applied to approximately a center of the hollow cylindrical substrate.

    [0030] Cleaning blades are conventional and well known in the art. Any suitable cleaning blade and cleaning blade holder may be used with the electrostatographic imaging member assembly 5 of this invention. In operation, the electrostatographic imaging member 5 is rotated in the direction shown by the arrow so that the cleaning blade assembly 15 rubs across the outer imaging surface of layer 25 in a "doctor" or chiseling attitude. The stick-slip interaction between the cleaning blade 30 and the imaging surface of imaging layer 25 can cause howling sounds to occur when electrostatographic imaging drum 10 does not contain the layer or bead of acoustic dampening compound 35. An acoustic dampening layer 35 according to a comparative example, as illustrated in the Figure, generally is applied and cured over a portion of the interior of hollow cylindrical substrate 20. The acoustic dampening compound used for the dampening layer 35 is in intimate contact with the interior surface of the hollow cylindrical substrate 20 such that the intimate contact ensures reduction or elimination of the squealing or howling sounds that can occur when the cleaning blade 30 contacts the outer imaging surface 25 of the electrostatographic imaging drum 10, and prevents relative movement between the acoustic dampening layer 35 and the hollow cylindrical substrate 20.

    [0031] In further embodiments, there is provided a method for dampening acoustic resonance in electrostatographic drums that comprises applying an acoustic dampening material to an electrostatographic drum. The electrostatographic drum may comprise a hollow cylindrical substrate, and at least one imaging layer. The acoustic dampening material is at least partially applied to an interior surface of the hollow cylindrical substrate. After applying the acoustic dampening material, the material is cured so that intimate contact is made between the acoustic dampening material and the interior surface of the hollow cylindrical substrate. The acoustic dampening material is applied in the form of one or more beads, and generally, only 20 grams or less of the acoustic dampening material is sufficient for use. However, in alternative embodiments, from about 5 grams to about 400 grams of the acoustic dampening material may be used. The acoustic dampening material may be, in embodiments, room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk, or mixtures thereof.

    [0032] Because electrostatographic drums require machining prior to coating, the optimal time and/or location in the fabrication process to apply the dampening compound is after counter-boring the end hubs (if necessary) and potentially to diamond turning the surface. Internal dampeners have been show to be beneficial during the diamond turning step, as disclosed in U.S. Patent No. 6,907,657.

    [0033] The acoustic dampening compound can be easily applied after finishing the second (final) counter-bore while the drum blank is still in the lathe. At this point, a dispensing probe with a right angle tip can be inserted into the drum interior to dispense the acoustic dampening compound material. The probe may be mounted parallel to the lathe cylindrical axis, and not co-linear to it. In this configuration, the probe is capable of rotating on its long axis, and capable of traversing down the lathe bed long axis (Z axis). This mounting arrangement would allow the probe to be inserted with the dispensing tip rotated away from the interior surface, and with the tip rotated into dispensing position, the probe can dispense the acoustic dampening compound (much like flow coating a fuser roll). Thereafter, the tip is rotated into the retraction position, and finally retracted from the drum interior.

    [0034] Generally, the electrostatographic imaging member may comprise an electrophotographic imaging member. Electrophotographic imaging members and electrographic imaging members are well known in the art and may be of any suitable configuration such as, for example, a flexible belt or a hollow cylinder, which is addressed by the embodiments described herein. Electrostatographic imaging members usually comprise a supporting substrate having an electrically conductive surface. Electrophotographic imaging members also comprise at least one photoconductive layer. A blocking layer may optionally be positioned between the substrate and the photoconductive layer. If desired, an adhesive layer may optionally be utilized between the blocking layer and the photoconductive layer. For multilayered imaging members, a charge generation layer is usually applied onto the blocking layer and a charge transport layer is subsequently formed over the charge generation layer. For electrographic imaging members, an electrically insulating dielectric layer is applied directly onto the electrically conductive surface. Any suitable, conventional, electrically insulating dielectric polymer may be used in the dielectric layer of the electrographic imaging member. The specific details of the various layers of an imaging member have been described further in, for example, U.S. Patent Nos. 4,415,639 , 5,686,215 and 5,153,618.

    [0035] While the description above refers to particular embodiments, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of embodiments herein.

    [0036] The presently disclosed embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, the scope of embodiments being indicated by the appended claims rather than the foregoing description. All changes that come within the meaning of and range of equivalency of the claims are intended to be embraced therein.

    EXAMPLE



    [0037] The example set forth herein below and is illustrative of different compositions and conditions that can be used in practicing the present embodiments. All proportions are by weight unless otherwise indicated. It will be apparent, however, that the embodiments can be practiced with many types of compositions and can have many different uses in accordance with the disclosure above and as pointed out hereinafter.

    Comparative Example



    [0038] An electrostatographic imaging member assembly was provided with a hollow electrostatographic drum and a cleaning blade assembly. The electrostatographic drum was of the XEROX Workcentre 55 family, and had a diameter of 84 mm. A thin layer of about 1 mm thick applied over a band or region of about 25 to about 75 mm near the middle of the interior side of the drum was sufficient to dampen acoustic resonance of the drum. This amount equates to between about 7 and about 20 grams of RTV type silicone on the Xerox Workcentre Pro 55 family drum(s). It has been shown from the testing that the more acoustic dampening compound material that is applied to the electrostatographic drum, the better the dampening will be. While the layer may have a thickness of from about 0.1 mm to about 6.0 mm, the data suggests that the dampening ability is more effective at the higher thicknesses.

    Example



    [0039] An electrostatographic imaging member assembly was provided with a hollow electrostatographic drum and a cleaning blade assembly. Two beads of RTV type silicone rubber were applied to the interior of an unflanged drum at two locations, each about 100 mm in from each end and approximately 10 grams of material in each bead. The drum was then mounted in a suitable clamp designed so as not to damp the resonance. When properly mounted and tapped with a wood stick, an undamped drum sounds much like a like a chime. On the other hand, the drum with the beads of RTV type silicone rubbers produced a dull thunk. Audio recordings of the sound clearly show that the acoustic resonance is quickly damped in the inventive drum having the beads of acoustic dampening compound. Based on the preliminary testing, it appears that a well-damped drum will not exhibit any of the undesirable sounds when operated in a suitable machine environment.


    Claims

    1. An electrostatographic drum comprising
    a hollow cylindrical substrate;
    at least one imaging layer disposed on the hollow cylindrical substrate; and
    an acoustic dampening material at least partially applied to an interior surface of the hollow cylindrical substrate
    characterized in that
    the acoustic dampening material is provided on the interior surface of the hollow cylindrical substrate in the form of one or more beads so that intimate contact is made between the acoustic dampening material and the interior surface of the hollow cylindrical substrate, and
    the acoustic dampening material is selected from the group consisting of room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk and mixtures thereof.
     
    2. The electrostatographic drum of claim 1, wherein the amount of acoustic dampening material used is no more than 20 grams.
     
    3. The electrostatographic drum of one of claims 1 and 2, wherein multiple beads of the acoustic dampening material are applied to the interior surface of the hollow cylindrical substrate.
     
    4. The electrostatographic drum of claim 3, wherein the multiple beads are applied to the interior surface of the hollow cylindrical substrate with each bead being applied about 100 mm in from each end of the hollow cylindrical substrate and optionally with one bead being applied to approximately a center of the hollow cylindrical substrate.
     
    5. A method for dampening acoustic resonance in an electrostatographic drum, comprising: applying an acoustic dampening material to an electrostatographic drum, wherein the electrostatographic drum comprises
    a hollow cylindrical substrate, and
    at least one imaging layer,
    characterized in that
    the acoustic dampening material is at least partially applied to an interior surface of the hollow cylindrical substrate and cured on the interior surface of the hollow cylindrical substrate in the form of one or more beads, the acoustic dampening material is selected from the group consisting of room temperature vulcanizing silicon rubber, high temperature vulcanizing silicone rubber, latex caulk and mixtures thereof, and
    curing of the acoustic dampening material is carried out so that intimate contact is made between the cured acoustic dampening material and the interior surface of the hollow cylindrical substrate.
     
    6. An electrostatographic imaging member assembly comprising:

    an electrostatographic drum as claimed in one of claims 1 to 4, and

    a cleaning blade assembly, wherein the cleaning blade assembly further comprises a cleaning blade, and

    a blade holder adapted to support the cleaning blade.


     


    Ansprüche

    1. Elektrostatografische Trommel, die umfasst:

    ein hohles zylindrisches Substrat;

    wenigstens eine auf dem hohlen zylindrischen Substrat angeordnete Abbildungsschicht und

    ein schalldämpfendes Material, das wenigstens teilweise auf die innere Fläche des hohlen zylindrischen Substrats aufgebracht wird,

    dadurch gekennzeichnet, dass

    das schalldämpfende Material an der inneren Fläche des hohlen zylindrischen Substrats in der Form von einem oder mehr Kügelchen bereitgestellt wird, so dass ein enger Kontakt zwischen dem schalldämpfenden Material und der inneren Fläche des hohlen zylindrischen Substrats hergestellt wird, und

    das schalldämpfende Material aus einer Gruppe ausgewählt wird, die aus einem bei Raumtemperatur vulkanisierendem Silikongummi, bei hoher Temperatur vulkanisierendem Silikongummi, einer Latex-Dichtungsmasse und deren Gemischen besteht.


     
    2. Elektrostatografische Trommel nach Anspruch 1, wobei die Menge des verwendeten schalldämpfenden Materials nicht mehr als 20 Gramm beträgt.
     
    3. Elektrostatografische Trommel nach einem der Ansprüche 1 und 2, wobei vielfache Kügelchen des schalldämpfenden Materials auf die innere Fläche des hohlen zylindrischen Substrats aufgebracht werden.
     
    4. Elektrostatografische Trommel nach Anspruch 3, wobei die vielfachen Kügelchen auf die innere Oberfläche des hohlen zylindrischen Substrats aufgebracht werden, wobei jedes Kügelchen etwa 100 mm von jedem Ende des hohlen zylindrischen Substrats aufgebracht wird und wobei optional ein Kügelchen ungefähr in einer Mitte des hohlen zylindrischen Substrats aufgebracht wird.
     
    5. Verfahren zum Dämpfen einer akustischen Resonanz in einer elektrostatografischen Trommel, das umfasst:

    Aufbringen eines schalldämpfenden Materials auf eine elektrostatografische Trommel, wobei die elektrostatografische Trommel umfasst:

    ein hohles zylindrisches Substrat und

    wenigstens eine Abbildungsschicht,

    dadurch gekennzeichnet, dass

    das schalldämpfende Material wenigstens teilweise auf eine innere Oberfläche des hohlen zylindrischen Substrats aufgebracht wird und an der inneren Oberfläche des hohlen zylindrischen Substrats in der Form von einem oder mehr Kügelchen aushärtet, wobei das schalldämpfende Material aus der Gruppe ausgewählt wird, die aus einem bei Raumtemperatur vulkanisierendem Silikongummi, bei hoher Temperatur vulkanisierendem Silikongummi, einer Latex-Dichtungsmasse und deren Gemischen besteht,
    und

    das Aushärten des schalldämpfenden Materials so ausgeführt wird, dass ein enger Kontakt zwischen dem ausgehärteten schalldämpfenden Material und der inneren Oberfläche des hohlen zylindrischen Substrats hergestellt wird.


     
    6. Elektrostatografische Abbildungselement-Anordnung, die umfasst:

    eine elektrostatografische Trommel nach einem der Ansprüche 1 bis 4 und

    eine Reinigungsklingenanordnung, wobei die Reinigungsklingenanordnung des Weiteren

    eine Reinigungsklinge und

    einen Klingenhalter umfasst, der angepasst ist, um die Reinigungsklinge zu tragen.


     


    Revendications

    1. Tambour électrostatographique comprenant :

    un substrat cylindrique creux ;

    au moins une couche d'imagerie disposée sur le substrat cylindrique creux ; et

    un matériau d'amortissement acoustique au moins partiellement appliqué sur une surface intérieure du substrat cylindrique creux

    caractérisé en ce que

    le matériau d'amortissement acoustique est prévu sur la surface intérieure du substrat cylindrique creux sous la forme d'une ou de plusieurs billes de manière à créer un contact intime entre le matériau d'amortissement acoustique et la surface intérieure du substrat cylindrique creux, et

    le matériau d'amortissement acoustique est choisi dans le groupe constitué du caoutchouc siliconé à vulcanisation à température ambiante, du caoutchouc siliconé à vulcanisation à haute température, et du mastic de latex et des mélanges de ceux-ci.


     
    2. Tambour électrostatographique selon la revendication 1, dans lequel la quantité du matériau d'amortissement acoustique utilisé n'est pas supérieure à 20 grammes.
     
    3. Tambour électrostatographique selon l'une des revendications 1 et 2, dans lequel les multiples billes du matériau d'amortissement acoustique sont appliquées sur la surface intérieure du substrat cylindrique creux.
     
    4. Tambour électrostatographique selon la revendication 3, dans lequel les multiples billes sont appliquées sur la surface intérieure du substrat cylindrique creux, chaque bille étant appliquée à environ 100 mm de chaque extrémité du substrat cylindrique creux et éventuellement une bille étant appliquée sur environ un centre du substrat cylindrique creux.
     
    5. Procédé pour l'amortissement de la résonance acoustique dans un tambour électrostatographique, comprenant :

    l'application d'un matériau d'amortissement acoustique sur un tambour électrostatographique, dans lequel le tambour électrostatographique comprend :

    un substrat cylindrique creux, et

    au moins une couche d'imagerie,

    caractérisé en ce que

    le matériau d'amortissement acoustique est au moins partiellement appliqué sur une surface intérieure du substrat cylindrique creux et durci sur la surface intérieure du substrat cylindrique creux sous la forme d'une ou de plusieurs billes, le matériau d'amortissement acoustique est choisi dans le groupe constitué du caoutchouc siliconé à vulcanisation à température ambiante, du caoutchouc siliconé à vulcanisation à haute température, du mastic de latex et des mélanges de ceux-ci, et

    le durcissement du matériau d'amortissement acoustique est réalisé de manière à créer un contact intime entre le matériau d'amortissement acoustique durci et la surface intérieure du substrat cylindrique creux.


     
    6. Ensemble d'élément d'imagerie électrostatographique, comprenant :

    un tambour électrostatographique selon l'une des revendications 1 à 4, et

    un ensemble de lame de nettoyage, où l'ensemble de lame i de nettoyage comprend en outre une lame de nettoyage, et

    un support de lame adapté pour supporter la lame de nettoyage.


     




    Drawing






    REFERENCES CITED IN THE DESCRIPTION



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    Patent documents cited in the description