Patent Application
20140186142
Not Applicable
Not Applicable
Not Applicable
1. Field of the Invention
The present invention relates to a device for controlling the application of glue to the binding of a book or magazine during the book binding process. More specifically the device relates to a computer controlled servo-motor and cam that can precisely adjust the distance from a doctor blade to the glue wheel to precisely control the thickness, and the spatial application, of the glue applied during the book binding process.
2. Description of the Related Art
The process of book binding is well know and the subject of numerous patents. See, for example, U.S. Pat. No. 3,866,568 issued to Minami on Feb. 18, 1975, and U.S. Pat. No. 4,014,287 issued to Green on Mar. 29, 1977 for general information on the book binding process. One of the main steps in bookbinding involves the application of an adhesive to the backbone of the assembled pages of a book or magazine. As used herein, the term bookbinding applies to the binding of any print publication, including books, magazines and catalogues, and the term book is used to refer to the material being bound, whether a book, a magazine, or a catalogue. The adhesive is typically glue, and most commonly the glue is made from petroleum based products. In modern bookbinding it is common to use “hot glue” or glue that is heated and that solidifies when it cools. This form of glue solidifies much quicker than other types of glues. The glue is applied to the book back, often called the spine, of the book by running the spine over a glue wheel or series of glue wheels which are covered with glue that is applied to the spine.
The application of the glue to the backbone is accomplished by means of glue wheels, which typically obtain the glue from a glue pot. The glue pot is a vessel that holds the liquid glue. Generally a portion of the glue wheel sits in the reservoir of glue and as it rolls the outer surface of the glue wheel picks up glue from the pot and transfers the glue to the top of the wheel. The back of the book, which is often referred to as the spine or backbone, is run over the top of the glue wheel to apply the glue. Typically the spine is pressed against the first glue wheel as it rolls across, which forces the pages apart slightly and allows the glue to spread between the pages. It is important to apply the appropriate amount of glue to the book back. If too little glue is applied the pages may not be properly bonded and the book may fall apart, and if too much glue is applied the pages might stick at an inconvenient distance from the spine and prevent the pages from opening. Glue is often the most expensive component of the book binding process, and the use of excess glue leads to waste, which will increase the cost of the binding process. There is the need, therefore, for a system to precisely control the amount of glue on the glue wheel to ensure sufficient glue to properly bind the book, while minimizing the amount of glue used and minimizing waste.
Another commonly encountered problem is that glue may be applied to too much of the spine. In old systems the glue wheel was entirely covered with glue, and the book back would pick up glue from the leading edge to the trailing edge. In general it is not desirable to get glue on the ends of the book back. There are a couple of reasons for this. One reason is that this glue may seep up between the pages and make the pages stick. One other reason is that it is a waste of glue. This is particularly true in binding magazines, where the ends of the bound book are trimmed off. If there is glue on the ends of the book back and pages it will be trimmed off, and will be totally wasted.
A device, known in the art of bookbinding as the doctor blade, is used to control the amount of glue on the wheel and which thus can be imparted onto the spine of the book. An example of a prior art doctor blade can be seen in U.S. Pat. No. 6,565,658 issued to Fischer et al., on May 20, 2003. The earliest doctor blades were fixed and therefore only controlled the thickness of the glue on the glue wheel. Modern doctor blades can move, reciprocating into and away from the glue wheel, from an open position where glue is allowed on the glue wheel, to a closed position, which is close enough to the glue wheel to essentially scrape the glue off the glue wheel and prevent glue from contacting the book back. Prior art doctor blades were typically controlled by a cam drive linkage that was attached to the drive mechanism of the machinery that moved the books through the binder. This system is not precise, and can allow too much or too little glue on the wheel, and also cannot be precisely controlled to prevent glue from adhering to the ends of the spine. There is a need, therefore, for a system to precisely control the thickness of the glue on the glue wheel.
The invention consists of a doctor blade that is precisely controlled to limit or control the application of glue to the spine of the book. The doctor blade is precisely controlled by a linkage attached to a servo motor with a cam, and the servo motor is controlled by a computerized control system to precisely time and position the doctor blade. This allows the doctor blade to control the thickness of the glue placed on the spine, and also controls the doctor blade to control the spatial placement of the glue along the spine.
The invention is a precisely controlled doctor blade that precisely controls the application of glue on the spine by controlling the glue on the glue wheel by controlled movement of the doctor blade. The doctor blade is moved by a servo motor attached to the doctor blade by a linkage. The servo motor is controlled by a computer operating system that can move the doctor blade based on the length of the spine and the desired placement of glue on the spine. The operating system operates based on information inputted by an operator, and also works with an electric eye that provides information on movement of the books in the binder so that the doctor blade opens and closes as the desired time to place glue in the precise location on the spine. The electric eye also allows the system to deal with a missing book, and prevents the doctor blade from opening, and thus applying glue to the wheel, when a book is missing.
Detailed embodiments of the present invention are disclosed herein. It is to be understood that the disclosed embodiments are merely exemplary of the invention, and that there may be a variety of other alternate embodiments. The figures are not necessarily to scale, and some features may be exaggerated or minimized to show details of particular components. Therefore, specified structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for teaching one skilled in the art to employ the varying embodiments of the present invention.
There are two main components of the invention. The first main component is a set of two precisely controlled doctor blades that control the amount of glue on the glue wheels, and hence the amount of glue imparted onto the book back, or spine of the book. Each of the doctor blades are controlled by a separate servo motor which allows the precise application of glue spacing and thickness onto the back of the book. The doctor blades, servo motors and related elements are shown in
As shown in
At the beginning of the book binding process a group of sheets of paper are collected into the book clamp 130. The book clamp 130 is shown in
Each of the steps of the biding process occurs at a set point in the system, so precise spacing and timing are very important for the successful operation of the binding system. Because of that, the book clamps 130 are evenly and precisely spaced around the binder carriage 120. And because of the need for proper timing, the various steps of the operations, page gathering, spine trimming, gluing, cover application, and book release, occur at precisely located points within the binder frame 110.
The glue pot 10 is a container to hold the glue G. The glue pot 10 is made from a pot bottom 11, a front wall 12, a first side wall 13, a second side wall 14 and a back wall 15. The walls 12, 13, 14 & 15 attach to the bottom in the conventional manner to create a container to hold the glue G. There is also an interior wall 16, that runs from the first side wall 13 to the second side wall 14 parallel to the back wall 15. The interior wall 16 does not attach to the pot bottom 11, leaving a small gap which allows the glue G to flow under the interior wall 16. The glue G is hot. It is pre-melted and heated in an external tank and then pumped into the glue pot 10 through a tube. There are a set of heating elements in the bottom of the glue pot 10 to keep the glue G at the proper temperature, which is generally between 275° F. to 350° F. The external heating components, delivery tubing and internal heating elements are known in the art and are not show and are not part of the invention.
As seen in
There are two servo motors 50a and 50b attached to the side walls 13 & 14 near the back wall 15. The servo motors 50a & 50b are standard, reciprocating, servo motors, wherein the shaft does not rotate fully but turns a controlled number of degrees. Such servo motors are well known in the art. The servo motor 50 is attached to a mounting plate 55 and the mounting plate 55 is attached to the side wall 13 or 14 near the back wall, as shown in the detail in
The doctor blade 30 consists of an attachment arm 35, which is mounted on an attachment plate 34. There is a pin hole 36 in the attachment arm 35, and the pin 54 runs through the attachment hole 36 and attaches the doctor blade 30 to the linkage 60. The doctor blade 30 also has two outwardly extending flanges 33, and a blade edge 32. There are a pair of gibs 40 mounted on the back wall 15 and interior wall 16 near the side wall 13 or 14. The gibs 40 have a recessed channel 43, and the outwardly extending flanges 33 slide in the channels 43. When the doctor blades 30 are slidably mounted in the gibs 40, and with the linkage 60 attaching the doctor blade 30 to the servo motor 50 by means of the eccentric cam 52, the doctor blade 30 will move toward and away from the glue wheel 20.
The binder carriage 120 runs in a continuous loop, and because of this is described, and spaced, as a 360 degree loop. It is called a 360 degree loop even though physically the carriage 120 moves on an elongated racetrack with two parallel sides with two 180 degree turns on each end, as seen in
The position of the book clamp 130 in the binder carriage 120 is measured from a clamp pin 135, which is positioned in the same place on each book clamp 130. The operation of every step in the binding system is timed or spaced off of the position of the clamp pin 135. There is a “0” degree timing mark located on the binder frame 110, and each step of the operation is spaced at a known location, in degrees of movement of the 360 degree carriage loop, from the “0” degree timing mark. This allows the system to be controlled and operated so that each step in the process is done at the correct time. This is done by aligning the clamp pin 135 with the “0” degree timing mark. The binder system operates off of this position, and each step of the position is spaced and time to operate when the book clamp 130 reaches the predetermined position for that step. So the trimming step will occur at a set and known distance from the “0” degree timing mark, and the glue application will occur at a set and known distance from the “0” degree timing mark.
Movement of the binder carriage loop is measured in milliseconds of angular movement, where one full loop is 360 degrees. Each millisecond correlates to a fraction of an inch, with the specific length depending on the overall length of the binder loop and the number of binder clamps in the loop. The binder carriage 120 has 27 clamp 130 positions. In the preferred embodiment these clamp positions are on 18″ centers.
When the binder 100 is in operation, the carriage 120 moves continuously. The movement of one book clamp 130 across any step is known as a machine cycle M, which is shown in
The present invention includes a control system that accurately and precisely controls the thickness of the glue G applied to the spine S, and accurately and precisely controls the spatial application of the glue G along the spine S. The control system does this by accurately and precisely knowing the position of the book clamp 130 in the system, and the spine S within the book clamp 130. This allows the control system to precisely control the position of the doctor blades 30a & 30b that control the application and thickness of the glue G on the glue wheels 20a & 20b, and thus the glue G that is applied to the spine S of the book B. Operation of the doctor blades 30a & 30b and glue wheels 20a & 20b is described in detail below.
The control system consists of a computerized controller 80, an electric eye 81 that is in electronic communication with the controller 80, and an encoder 85 that is also in electronic communication with the controller 80. These elements are shown in a schematic view in
The electric eye 81 is mounted on the binder frame 110 at the “0” timing mark 115. The electric eye 81 is a standard electric eye and is mounted so that it is triggered by the movement of a book across its field of view. The electric eye 81 is electronically connected to the controller 80 by a standard connecting cable, and tells the controller 80 if there is a book in the book clamp 130. If there is no book in the book clamp 130, the controller 80 will not send a signal to open the servo motors 50a & 50b and the servo motor will not open the doctor blade 30 when that particular clamp 130 arrives at the glue wheels 20.
There is an encoder 85 that is connected to the binder frame 110 and is in electronic communication with the controller 80. The encoder 85 provides the controller 80 with an encoder signal that has information on the rate of movement of the books B through the binder. In the preferred embodiment the encoder 85 is a simple electromagnetic device that generates a pulse based on the movement of the binder carriage. This pulse is the encoder signal and it is timed to correspond to the movement of the clamps in the binder carriage. This allows the controller 80 to track the movement of the book clamps 130 regardless of the actual speed of the carriage 130. The encoder 85 also allows the controller 80 to divide the machine cycle into many very small parts, based on the timing of each electronic pulse. The encoder 85 pulses for each pre-set segment of the machine cycle M. So if, as in the preferred embodiment, the machine cycle is 18 inches, and the encoder 85 is pre-set in segments of 8000 pulses per machine cycle, this allows the controller 80 to break the 18 inch machine cycle into 8000 equal parts of 0.00225 inches. This means that each pulse of the encoder 85 signifies movement of the carriage 120 of 0.00225 inches. This allows the controller 80 to track and locate the book clamp 130 in 0.00225 inch segments, which allows very precise controlling of the doctor blades 30 and the glue position spatially along the length of the spine S.
The encoder signal allows the controller 80 to know precisely when the leading edge S1 of the book B will come into contract with the first glue wheel 20a. With the position information provided by the electric eye 81, and the movement information provided by the encoder 85, the computerized controller 80 can be programmed so that the first doctor blade 30a will open at the precisely controlled moment so as to begin the placement of glue G on the glue wheel 20 to allow the precise application of the glue G at the precisely desired point on the book back S. The length of the binder carriage loop is precisely known, the distance between the books B are known, and the encoder 85 and electric eye 81 communicate the position of the book back S to the controller 80, the controller 80 will know precisely when to activate the servo motors 50a & 50b to open the doctor blades 30a & 30b to allow the glue G on the glue wheels 20a & 20b to reach the spine S and the precise position.
If, for example, the glue wheel 20 has a 4 inch diameter it will have a circumference of 12.56637″. If the doctor blade 30 is set at the equator of the wheel 20, or at 270 degrees, it must open one quarter turn, or 3.14159″ before the glue will be at the top of the glue wheel 20. Typically, however, it is not desirable for the glue G to begin at the leading edge S1 of the spine S, or end precisely at the trailing edge S2, because this will cause glue G to seep over the back edges of the book when the cover is applied. It is preferred to start the glue G on the spine S some distance from the leading edge S1 and stop the glue some distance before the trailing edge S2. For most books B the distance that glue G begins from the leading edge S1 is 3/32 (0.09375″) of an inch, and application stops at 3/32 (0.09375″) of an inch from the trailing edge S2. This means that the doctor blade 30 will open 3/32 of an inch later than a quarter turn, or will open at 3.04784 inches before the leading edge S1 reaches the top 23 of the glue wheel 20. Because the spacing of the system is known, and programmed into the controller 80, the controller 80 will know when the leading edge S1 of the spine S of the book b will reach the top 23 of the glue wheel for glue application. If glue G is to be applied starting exactly at the leading edge S1, then the doctor blade 30 will open at the precise predetermined point before the hand.
The controller 80 is connected to the first servo motor 50a by means of a first communication cable 82 and connected to the second servo motor 50b by means of the second communication cable 83. Based on the information inputted into the controller 80 by the operator, the controller 80 will take the information from the electric eye 81 and the encoder 85, process it with the control software, and operate the servo motors 50a & 50b to precisely open the doctor blades 30a & 30b to precisely apply the glue to the book back S. The software which is internal to the controller is essentially running off information from the 360 degree loop of the carriage. This means that the software knows that a book will arrive at position 0.0, position 13.3, position 26.6, etc. The software knows the size of the machine cycle M and the spacing in milliseconds (which corresponds to 0.0025 inches). This will allow the software to activate the servo motors 50a & 50b at the appropriate times.
The operator can input the desired glue thickness, which can range from the closed position of 0.003 inches to the maximum open position of 0.035 inches. Typically the applied glue thickness ranges between 0.018 inches and 0.035 inches depending on the type of book being bound. The controller can also input the length of the book back S, as well as the desired distance from the leading edge S1 of the book B to begin glue application and desired distance from the trailing edge S2 to end glue G application. For most books B the distance that glue G begins from the leading edge S1 is 3/32 (0.09375″) of an inch, and application stops at 3/32 (0.09375″) of an inch from the trailing edge S2. The system is designed so that the servo motors 50a & 50b will open the doctor blades 30a & 30b on the glue wheels 20a & 20b at precisely the proper time so that as the glue wheel 20 rolls it will have glue G on the wheel for application onto the book back S at the desired point. The doctor blades 30a & 30b will then close at the desired time so that the glue will no longer be on the glue wheel 20 at the desired distance from the trailing edge S2 of the book B.
As the leading edge S1 of a book B approaches the glue wheel 20a, the controller 80 sends a position commands to the servo motor 50a to set the thickness of the glue G on the glue wheel 20a. The controller 80 can also vary the thickness of the glue G as the book B passes over the glue wheels 20a & 20b. For example, the glue thickness can be set to be different for each ⅓ of the spine S. The glue thickness can be varied linearly over the length of the spine S of the book B. For example it might have a starting thickness near the leading edge S1 of the book of 0.010 inch and an ending thickness near the trailing edge S2 of 0.020 inch. The glue thickness would decrease to 0.080 when one quarter of the book had passed the glue wheel 20, then decrease to 0.060 inch when one half of the book B had passed the glue wheel 20, and so on.
The present invention is well adapted to carry out the objectives and attain both the ends and the advantages mentioned, as well as other benefits inherent therein. While the present invention has been depicted, described, and is defined by reference to particular embodiments of the invention, such reference does not imply a limitation to the invention, and no such limitation is to be inferred. The depicted and described embodiments of the invention are exemplary only, and are not exhaustive of the scope of the invention. Consequently, the present invention is intended to be limited only be the spirit and scope of the claims, giving full cognizance to equivalents in all respects.
This application is a continuation in part of U.S. provisional application No. 61/580,910, filed on Dec. 28, 2011, and a continuation in part of U.S. application Ser. No. 13/727,716, filed on Dec. 27, 2012, both incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 13727716 | Dec 2012 | US |
| Child | 13904338 | US |
