Patent Publication Number: US-11654649-B2

Title: Paper tube making apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a paper tube making apparatus, which prevents environmental temperature and humidity from affecting extent of drying of glue that is applied to a paper tape. 
     2. The Related Arts 
     A paper tube making apparatus is operated by generally applying and coating glue on at least one paper tape that is subsequently wound to form a paper tube. The paper tube is then subject to cutting by a cutter in order to manufacture paper tubes of a predetermined length. The paper tube has various uses. For example, a paper tube may serve as a paper drinking straw. In addition, toilet tissue may be wound around a paper tube to provide a toilet paper roll. 
     The paper tape is coated glue in order to be bonded together. The glue is susceptible to environmental variations, such as temperature and humidity, and the extent of drying and thus bonding power of the glue are affected. This may lead to deterioration of quality of a paper tube so manufactured. In practical applications, the formulation of the glue must be modified according to the temperature and humidity, and this causes difficulty of manufacturing. Without properly modifying the glue formulation to the best according to the temperature and humidity, the quality of the paper tube would be affected. 
     To overcome the above-discussed issues of the prior art, the present invention provides a novel paper tube making apparatus, which enhances efficiency of paper tube generation and prevents variations of temperature and humidity from affecting the quality of the paper tube. 
     SUMMARY OF THE INVENTION 
     An objective of the present invention is to provide a paper tube making apparatus, which includes a hot airflow generation unit that generates and blows a hot airflow toward at least one paper tape, in order to stabilize the extent of drying of glue coated on the paper tape, and a paper tape winding mechanism that wraps and winds the paper tape around a fixed rod to form a paper tube, so that the quality of the paper tube so formed is enhanced. 
     An objective of the present invention is to provide a paper tube making apparatus, which includes a length measurement unit arranged an upstream of the paper tape winding mechanism and the fixed rod to measure a conveying speed of the paper tape. The hot airflow generation unit is operable to adjust a flow rate and a temperature of the hot airflow according to the conveying speed of the paper tape, in order to stabilize the extent of drying of glue coated on the paper tape. 
     An objective of the present invention is to provide a paper tube making apparatus, which controls the extent of drying of the glue coated on the paper tape using the hot airflow generated by the hot airflow generation unit so as to reduce the influence on the extent of drying of the glue by environment temperature or humidity and also to effectively enhance the fabrication quality of the paper tube. 
     To achieve the above objectives, the present invention provides a paper tube making apparatus, which comprises: a fixed rod; a paper tape winding mechanism, which is arranged adjacent to the fixed rod, wherein the fixed rod and the paper tape winding mechanism receive a paper tape, and the paper tape winding mechanism is operable to wind the paper tape around the fixed rod to form a paper tube; a glue applying device, which is arranged an upstream of the fixed rod and the paper tape winding mechanism and is operable to coat glue on the paper tape; a length measurement unit, which is arranged the upstream of the fixed rod and the paper tape winding mechanism and is operable to measure a conveying speed of the paper tape; and a hot airflow generation unit, which is arranged between the glue applying device and the paper tape winding mechanism to generate a hot airflow, wherein the hot airflow generation unit adjusts a flow rate and a temperature of the hot airflow according to the conveying speed of the paper tape. 
     The paper tube making apparatus comprises a cutter, which is arranged adjacent to the fixed rod and is operable to cut the paper tube formed on the fixed rod. 
     The paper tube making apparatus comprises a drive mechanism, which is connected to the cutter and is operable to drive the cutter to move along the fixed rod. 
     In the paper tube making apparatus, the paper tape winding mechanism comprises a supporting base, a driving roller, at least one pulley, and a belt, the driving roller and the pulley being mounted on the supporting base, the belt being wound around the driving roller, the pulley, and the fixed rod, wherein the paper tape is located between the belt and the fixed rod, such that the driving roller, when rotating, drives the belt to wind the paper tape around the fixed rod to form the paper tube. 
     The paper tube making apparatus comprises at least one transportation roller, which is arranged the upstream of the fixed rod and the paper tape winding mechanism to convey the paper tape to the fixed rod and the paper tape winding mechanism, the length inspection unit being connected to the transportation roller and being operable to count turns of rotation of the transportation roller in order to determine the conveying speed of the paper tape. 
     The paper tube making apparatus comprises a calculation unit that is in electrical connection with the length measurement unit and the hot airflow generation unit, and is operable to calculate the conveying speed of the paper tape according to a conveyed length of the paper tape measured by the length measurement unit, and is operable to control the flow rate and the temperature of the hot airflow generated by the hot airflow generation unit according to the conveying speed of the paper tape. 
     In the paper tube making apparatus, the length measurement unit is arranged the upstream of the glue applying device. 
     In the paper tube making apparatus, the glue applying device comprises a glue applying roller and a glue tank. The glue tank receives and holds glue. The glue applying roller is arranged in contact with the glue received and held in the glue tank and is operable to coat the glue on the paper tape in contact therewith. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic view showing a structure of a paper tube making apparatus according to an embodiment of the present invention; 
         FIG.  2    is a schematic view showing, in an enlarged form, a fixed rod and a paper tape winding mechanism of the paper tube making apparatus according to an embodiment of the present invention; 
         FIG.  3    is a schematic view showing a cutter of the paper tube making apparatus according to an embodiment of the present invention; and 
         FIG.  4    is a schematic view showing a glue applying device of the paper tube making apparatus according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to  FIGS.  1  and  2   , which are, respectively, a schematic view showing a structure of a paper tube making apparatus according to an embodiment of the present invention and a schematic view showing, in an enlarged form, a fixed rod and a paper tape winding mechanism. As shown in the drawings, the paper tube making apparatus  10  generally comprises a fixed rod  11 , a paper tape winding mechanism  13 , a hot airflow generation unit  14 , a length measurement unit  17 , a glue applying device  19 , and a cutter  151 . The paper tape winding mechanism  13  and the fixed rod  11  are arranged to receive a paper tape  121 , and the paper tape winding mechanism  13  is operable to wrap or wind the paper tape  121  around the fixed rod  11  to form or generate a paper tube  123 . 
     The fixed rod  11  is of a cylindrical form or an elongate bar. The paper tape winding mechanism  13  is arranged adjacent to the fixed rod  11 . For example, the fixed rod  11  is arranged as being fixed to a machine frame  110 , such that the fixed rod  11  is not rotatable or movable relative to the machine frame  110 . 
     In an embodiment of the present invention, the paper tape winding mechanism  13  comprises a supporting plate  131 , a driving roller  133 , at least one pulley  135 , and a rolling belt  137 . The supporting plate  131  can be in the form of an arm plate, and the driving roller  133  and the pulley  135  are mounted on the supporting plate  131  and are rotatable relative to the supporting plate  131 . The belt  137  is looped or wound around the driving roller  133  and the pulley  135 , such that the driving roller  133 , when driven by a motor to rotate, would drive the pulley  135  to rotate by means of the belt  137 . 
     The belt  137  of the paper tape winding mechanism  13  is wound around the fixed rod  11  in the way shown in  FIG.  2   . For example, the driving roller  133  and the pulley  135  of the paper tape winding mechanism  13  are respectively located below and above the fixed rod  11 , and a portion of the belt  137  that is located between the driving roller  133  and the pulley  135  is wound around the fixed rod  11 . When the driving roller  133  rotates, the belt  137  is caused to move relative to the fixed rod  11 . 
     In a practical application, at least one paper tape  121  is positioned such that a portion thereof is located in a gap between the fixed rod  11  and the belt  137 , and when the driving roller  133  rotates and thus drives the belt  137  to move relative to the fixed rod  11 , the belt  137  is caused to wrap or wind the portion of the paper tape  121  located between the fixed rod  11  and the belt  137  around the fixed rod  11  to form a paper tube  123 . The paper tube  123 , as being generated in this way, continuously extends or elongates along the fixed rod  11  in a direction toward the cutter  151 , until the driving roller  133  stops rotation. In the example shown in the drawings, the present invention is embodied by wrapping or winding one single paper tape  121  around the fixed rod  11  to form the paper tube  123 ; however, in other embodiments, multiple paper tapes  121  may be wound together around the fixed rod  11  to form the paper tube  123 . 
     In an embodiment of the present invention, the supporting plate  131  is mounted to the machine frame  110  in a manner of being swinging or rotating relative to the machine frame  110 . When the supporting plate  131  swings relative to the fixed rod  11 , an angle at which the belt  137  is wound around the fixed rod  11  is changed so as to vary or adjust a feed-in angle of the paper tape  121  fed onto the fixed rod  11 . The above-described specifics or details of the structure of the paper tape winding mechanism  13  are provided to illustrate one embodiment of the present invention and are not intended to impose undue constraint to the scope of protection that the present invention seeks for. 
     The paper tube making apparatus  10  may comprise a cutter  151 , and the cutter  151  is arranged adjacent to the fixed rod  11  and is operable to cut the paper tube  123  formed on the fixed rod  11  into fixed-length pieces of the paper tube  123 . In an embodiment of the present invention, as shown in  FIG.  3   , the cutter  151  comprises a base plate  1511 , a plurality of rolling cutters  1513 , and a plurality of swing arms  1515 . Each of the rolling cutters  1513  is connected by a corresponding one of the swing arms  1515  to the base plate  1511 . In an example, the number of the rolling cutters  1513  is three. 
     The base plate  1511  is formed with a through hole  1512 , so that the fixed rod  11  and/or the paper tube  123  are extended through the through hole  1512  of the base plate  1511 . The rolling cutters  1513  are arranged on a circumference around the through hole  1512 , so as to be set in a circumferentially distributed manner. The swing arms  1515  are operable to drive the rolling cutters  1513  to swing or rotate relative to the base plate  1511 , such that the rolling cutters  1513  are moved relative to the through hole  1512  of the base plate  1511  and the fixed rod  11  and/or the paper tube  123 . For example, a motor can be used to drive the swing arms  1515  to rotate or swing or oscillate. In cutting the paper tube  123 , the swing arms  1515  are operated to drive the rolling cutters  1513  to move toward the fixed rod  11  and the paper tube  123  in order to cut the paper tube  123  formed on the fixed rod  11 . The above-described specifics or details of the structure of the cutter  151  are provided to illustrate one embodiment of the present invention and are not intended to impose undue constraint to the scope of protection that the present invention seeks for. 
     The cutter  151  is connected to a drive mechanism  153 , and the drive mechanism  153  is operable to drive the cutter  151  to move along the fixed rod  11 . In an example, the drive mechanism  153  comprises a stepping motor. Specifically, the moving speed of the cutter  151  is set identical or close to a generation speed of the paper tube  123 , in order to prevent the paper tube  123  from pushing side surfaces of the cutter  152  during the paper tube  123  being cut off by the cutter  151 . 
     Further, before the paper tape  121  is wound by the paper tape winding mechanism  13  to form the paper tube  123 , glue must be applied and coated on the paper tape  121 , such that the glue bonds portions of the paper tape  121  in an overlapping zone to form the paper tube  123 . In an embodiment of the present invention, a glue applying device  19  is arranged an upstream of the fixed rod  11  and the paper tape winding mechanism  13 , and the glue applying device  19  is operable to apply and coat the glue on a portion or the entirety of a surface of the paper tape  121 . 
     In an embodiment of the present invention, as shown in  FIG.  4   , the glue applying device  19  comprises a glue applying roller  191  and a glue tank  193 . The glue tank  193  contains and holds the glue therein. The glue applying roller  191  is arranged to contact the glue held in the glue tank  193 , such that when the glue applying roller  191  rotates, the glue is attached to and spread on a surface of the glue applying roller  191 . During a process of conveyance or feeding, the paper tape  121  contacts the surface of the glue applying roller  191  so that the glue applying roller  191  applies and coats the glue on a surface of the paper tape  121 . 
     To allow the glue to coat on the paper tape  121  in a uniform manner, at least one doctor blade may be used to scrape off extra glue from the surface of the glue applying roller  19 . For example, the doctor blade is set in contact with the surface of the glue applying roller  191 , such that when the glue applying roller  191  is rotating relative to the doctor blade, the doctor blade scrapes the extra glue from the surface of the glue applying roller  191 , making the amount of glue on the surface of the glue applying roller  191  fixed and ensuring the glue applying roller  191  may continuously coat a fixed amount of glue on the paper tape  121 . 
     Although proper operation of the glue applying device  19  helps keep the amount of glue coated on the paper tape  121  constant or consistent, the drying speed or drying rate of the glue is affected by the environment temperature and humidity, and this in turn affects the quality of the paper tube  123  so manufactured. Specifically, before the paper tape  121  is would around the paper tube  123 , the glue coated on the paper tape  121  must be first dried to a certain extent, such as being partially dried, in order to adhesively bond the paper tape  121  in such a way as to enhance and stabilize the quality of the paper tube  123 . 
     In case that the glue coated on the paper tape  121  is in a condition of being excessively wet, during the process of bonding, the glue often overflows the paper tape  121  and remains on a surface of the paper tube  123  to subsequently attach on and adhere to other mechanisms. For example, when the cutter  151  is cutting off the paper tube  123 , the glue that remains on the paper tube  123  may adhere to the cutter  151 . Further, during the cutter  151  is cutting off the paper tube  123 , the glue, if not completely or properly dried, may cause the paper tube  123  to decompose and disintegrate, so as to affect the generated quality of the paper tube  123 . Oppositely, glue that is excessively dried on the paper tape  121  would incapable of bonding the paper tape  121  to form the paper tube  123 , and a similar condition of decomposition or disintegration may happen when the paper tube  123  is cut by the cutter  151 . 
     Specifically, when the environment temperature is relatively high while the humidity is relatively low, the rate at which the glue coated on the paper tape  121  is being dried is fast. Oppositely, when the environment temperature is relatively low while the humidity is relatively high, the rate at which the glue coated on the paper tape  121  is being dried is slow. Due to such a reason, the prior art commonly modifies the formulation of the glue according to the environment temperature and humidity. For example, when the environment temperature is relatively high while the humidity is relatively low, the ratio of water contained in the glue is increased, and when the environment temperature is relatively low while the humidity is relatively high, the ratio of water contained in the glue is decreased. 
     In practical applications, there is no way to establish a quantified relationship between the environment temperature and humidity and the formulation of glue, and it generally relies on the experience of an operator to adjust and modify the formula of the glue. Such an operation of adjusting and modifying the formula of the glue needs a certain period of time for testing and adjusting and this would inevitably affect the efficacy and quality of production of the paper tube  123 . 
     Further, the speed at which the paper tape  121  is conveyed or forwarded may also affect the extent of drying of the glue. For example, when the paper tape  121  is conveyed or forwarded at a fast speed, the glue would be in a relatively wet condition when the paper tape  121  reaches the paper tape winding mechanism  13 , and when the paper tape  121  is conveyed or forwarded at a slow speed, the glue would be in a relatively dry condition when the paper tape  121  reaches the paper tape winding mechanism  13 . Due to such a reason, the prior art makes adjustment on a distance between the glue applying device  19  and the paper tape winding mechanism  13  according to the conveying speed of the paper tape  121 , such that when the paper tape  121  reaches the paper tape winding mechanism  13 , the glue has achieved a desired extent of dry. This certainly adds difficulty to the use thereof and lowers down the production speed of the paper tube  123 . 
     To avoids the above-described problems, the present invention further includes the hot airflow generation unit  14  and the length measurement unit  17  that are arranged an upstream of the fixed rod  11  and the paper tape winding mechanism  13 . For example, the length measurement unit  17  is arranged the upstream of the glue applying device  19  to measure a conveyed length and/or a conveying speed of the paper tape  121 . The hot airflow generation unit  14  is arranged between the glue applying device  19  and the paper tape winding mechanism  13  to generate and supply a hot airflow. Preferably, the flow rate and temperature of the hot airflow generated by the hot airflow generation unit  14  is adjustable. 
     In an embodiment of the present invention, at least one transportation roller  171  is arranged the upstream of the fixed rod  11  and the paper tape winding mechanism  13  and the transportation roller  171  functions to convey and supply the paper tape  121  onto the fixed rod  11  and the paper tape winding mechanism  13 . The length measurement unit  17  is connected to one such transportation roller  171  to count the turns of rotation of the transportation roller  171  so as to calculate the conveyed length and/or the conveying speed of the paper tape  121 . 
     In an embodiment of the present invention, the hot airflow generation unit  14  is in electrical connection with the length measurement unit  17  to adjust the flow rate and/or temperature of the hot airflow generated by the hot airflow generation unit  14  according to the conveyed length and/or conveying speed of the paper tape  121  measured by the length measurement unit  17 . 
     By directing the hot airflow generated by the hot airflow generation unit  14  toward the glue coated on the paper tape  121 , the extent of drying of the glue can be controlled and the influence of the environment temperature or humidity on the extent of drying of the glue can be reduced, so that there is no need to do modification or change of the formulation of the glue according to the environment temperature and humidity. 
     Specifically, during fabrication of the paper tube  123  using the paper tube making apparatus  10  according to the present invention, one major factor that affects the extent of drying of the glue is the conveying speed of the paper tape  121 . When the conveying speed of the paper tape  121  is fast, the time period within which the glue coated on the paper tape  121  is being in contact with the hot airflow is short, so that the glue coated on the paper tape  121  that has passed the hot airflow generation unit  14  is relatively wet. Oppositely, when the conveying speed of the paper tape  121  is slow, the time period within which the glue coated on the paper tape  121  is being in contact with the hot airflow is increased, so that the glue coated on the paper tape  121  that has passed the hot airflow generation unit  14  becomes relatively dry. 
     For such a reason, the present invention further proposes adjusting the flow rate and temperature of the hot airflow generated by the hot airflow generation unit  14  according to the conveying speed and/or the conveyed length of the paper tape  121 , so that when the paper tape  121  is going to wind to form the paper tube  123 , the glue coated on the paper tape  121  may have consistent or fixed extent of drying to thereby prevent the glue coated on the paper tape  121  from becoming excessively dried or excessively wet and thus effectively enhance the quality of the paper tube  123  so fabricated. 
     Specifically, when the conveying speed of the paper tape  121  is fast, the temperature and flow rate of the hot airflow generated by the hot airflow generation unit  14  may be increased. Oppositely, when the conveying speed of the paper tape  121  is slow, the temperature and flow rate of the hot airflow generated by the hot airflow generation unit  14  may be reduced. By means of the above-described way of adjustment, the extent of drying of the glue coated on the paper tape  121  can be kept consistent at the time when the paper tape  121  is being wound to form the paper tube  123 . 
     In a further embodiment of the present invention, the adjustment of the temperature and flow rate of the hot airflow generated by the hot airflow generation unit  14  can be made according to factor including the material, width, and thickness of the paper tape  121 , the type and formula of the glue, and/or the thickness of coating. 
     In practical applications, the paper tube making apparatus  10  may comprise a calculation unit  18 . In an example, the calculation unit  18  is or comprises a computer. The calculation unit  18  is in electrical connection with the length measurement unit  17  and the hot airflow generation unit  14 , and receives data of the conveyed length of the paper tape  121  from the length measurement unit  17  in order to calculate the conveying speed of the paper tape  121 , and to control the flow rate and temperature of the hot airflow generated by the hot airflow generation unit  14  according to the conveying speed of the paper tape  121 . 
     The above description is made only to provide an illustration of a preferred embodiment of the present invention and is not intended to limit the scope of embodiment of the present invention. Equivalent variation and modification in respect of shape, structure, feature, and spirit that fall within the appended claims with which the present invention is solely defined are considered within the scope of the present invention as defined in the claims.