Hot-melt Adhesive Temperature Control Method, Applicator Therefor, and Bookbinding Apparatus

Abstract

Bookbinding apparatus adhesive applicator accurately, briefly controls adhesive temperature to a set value by selecting, in accordance with adhesive initial temperature, one of a plurality of temperature-controller heating modes defining different supply powers and supply durations for supplying power to an adhesive-container heater to control its heating temperature. A sensor detects the temperature of the adhesive in the container at applicator start-up, or on restarting a post-standby applicator. In accordance with the detected temperature, one of the heating modes is selected to heat the adhesive. The applicator warm-up time is thus set in response to the state of the adhesive: If solidified, the adhesive is heated and melted in a maximum supply-power, supply-duration mode; if low-temperature liquefied at, it is heated and melted in a second-magnitude supply-power, supply-duration mode; and if the adhesive temperature is high, it is heated and melted in a minimal supply-power, supply-duration mode.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is explanatory drawings showing a configuration of an adhesive container that holds solid adhesive, wherein FIG. 1A is a perspective view of an external shape, FIG. 1B is a sectional view in the X-X direction, and FIG. 1C is a sectional view in the Y-Y direction;

FIG. 2 is a block diagram of a configuration of a temperature control means that heats and melts solid adhesive;

FIG. 3 is a flowchart of actions of the temperature control means;

FIG. 4 is charts diagramming temperature fluctuations when in a heating mode in a temperature control of heating means, wherein FIG. 4A shows temperature fluctuations in a first heating mode, FIG. 4B shows temperature fluctuations in a second heating mode, and FIG. 4C shows temperature fluctuations in a third heating mode;

FIG. 5 is a view of an image forming system with the adhesive applicator of FIG. 1 built in; and

FIG. 6 is a view of the essential portion of the bookbinding apparatus of FIG. 5.

Claims

1. An adhesive applicator comprising: a container for storing hot-melt adhesive;heating means disposed on the container, for melting to a predetermined temperature solid adhesive filled in the container;sensor means for detecting the temperature of the adhesive in the container;temperature control means for controlling the heating temperature of the heating means in response to the temperature detected by the sensor means; andapplication means for applying the adhesive in the container to a body of documents; wherein the temperature control means is configured to have a plurality of heating modes with different supply levels and supply durations for supplying power to the heating means; andpower is supplied to the heating means in a single heating mode selected in response to the temperature of the adhesive detected by the sensor means.

2. The adhesive applicator according to claim 1, wherein: power whose level is varied stepwise per unit time is supplied until the adhesive in the container reaches a preestablished temperature; andthe plurality of heating modes is constituted by a plurality of modes in which the stepwise-varied power levels differ.

3. The adhesive applicator according to claim 1, wherein: the sensor means is configured with a liquid temperature sensor for directly detecting the temperature of the adhesive within the container, and a heating unit temperature sensor for detecting the temperature of a heating unit disposed in the heating means;the temperature control means selects one of the plurality of heating modes based on the temperature detected by liquid temperature sensor or the heating unit temperature sensor when the applicator is tuned on; andthe selected heating mode varies the current level supplied to the heating means stepwise, based on the temperature detected by the heating unit temperature sensor, until the adhesive reaches a preestablished temperature.

4. The adhesive applicator according to claim 2, wherein: the sensor means is configured with a liquid temperature sensor for directly detecting the temperature of the adhesive within the container, and a heating unit temperature sensor for detecting the temperature of a heating unit disposed in the heating means;the temperature control means selects one of the plurality of heating modes based on the temperature detected by liquid temperature sensor or the heating unit temperature sensor when the applicator is tuned on; andthe selected heating mode varies the current level supplied to the heating means stepwise, based on the temperature detected by the heating unit temperature sensor, until the adhesive reaches the preestablished temperature.

5. The adhesive applicator according to claim 1, wherein: a stirring rotor is provided within the container for stirring adhesive inside it; andthe stirring rotor is provided with a drive means for rotationally driving the stirring rotor when the sensor means reaches a preestablished, predetermined temperature.

6. The adhesive applicator according to claim 2, wherein: a stirring rotor is provided within the container for stirring adhesive inside it; andthe stirring rotor is provided with a drive means for rotatively driving the stirring rotor when the sensor means reaches a preestablished, predetermined temperature.

7. The adhesive applicator according to claim 3, wherein: a stirring rotor is provided within the container for stirring adhesive inside it; andthe stirring rotor is provided with a drive means for rotatively driving the stirring rotor when the sensor means reaches a preestablished, predetermined temperature.

8. The adhesive applicator according to claim 5, wherein: the stirring rotor is constituted by an applicator roller provided in the container;the drive means is constituted by a reversible drive motor for forward-/reverse-rotating the applicator roller; andthe drive motor is controlled to rotationally start when a heating unit temperature sensor for detecting the temperature of the container heating means reaches a predetermined temperature, and to rotate in the opposite direction after a predetermined amount of time has elapsed after the rotational start.

9. The adhesive applicator according to claim 6, wherein: the applicator roller constituting the stirring rotor rotationally starts after a preestablished delay time has elapsed after the sensor means has reached a predetermined temperature, the delay time being set to times that respectively differ depending on the heating mode; andthe preestablished time delays the timing of the rotational start to an extent that the temperature detected by the sensor means is a low temperature when the applicator is turned on.

10. The adhesive applicator according to claim 7, wherein: the applicator roller constituting the stirring rotor rotationally starts after a preestablished delay time has elapsed after the heating unit temperature sensor has reached a predetermined temperature, the delay time being set to times that respectively differ depending on the heating mode; andthe preestablished time delays the timing of the rotational start to an extent that the temperature detected by the sensor means is a low temperature when the applicator is turned on.

11. A bookbinding apparatus comprising: stacking means for aligning into a bundle sheets fed out sequentially;sheet-bundle transport means for transporting a sheet bundle from the stacking means into a predetermined binding position;an adhesive applicator according to claim 1, for applying adhesive to an edge of a sheet bundle in the binding position; andsheet bundle convey-out means for conveying out sheet bundles adhesive-processed by the adhesive applicator.

12. A bookbinding apparatus comprising: stacking means for aligning into a bundle sheets fed out sequentially;sheet-bundle transport means for transporting a sheet bundle from the stacking means into a predetermined binding position;an adhesive applicator according to claim 2, for applying adhesive to an edge of a sheet bundle in the binding position; andsheet bundle convey-out means for conveying out sheet bundles adhesive-proceessed by the adhesive applicator.

13. A bookbinding apparatus comprising: stacking means for aligning into a bundle sheets fed out sequentially;sheet-bundle transport means for transporting a sheet bundle from the stacking means into a predetermined binding position;an adhesive applicator according to claim 3, for applying adhesive to an edge of a sheet bundle in the binding position; andsheet bundle convey-out means for conveying out sheet bundles adhesive-proceessed by the adhesive applicator.

14. A bookbinding apparatus comprising: stacking means for aligning into a bundle sheets fed out sequentially;sheet-bundle transport means for transporting a sheet bundle from the stacking means into a predetermined binding position;an adhesive applicator according to claim 4, for applying adhesive to an edge of a sheet bundle in the binding position; andsheet bundle convey-out means for conveying out sheet bundles adhesive-proceessed by the adhesive applicator.

15. A bookbinding apparatus comprising: stacking means for aligning into a bundle sheets fed out sequentially;sheet-bundle transport means for transporting a sheet bundle from the stacking means into a predetermined binding position;an adhesive applicator according to claim 5, for applying adhesive to an edge of a sheet bundle in the binding position; andsheet bundle convey-out means for conveying out sheet bundles adhesive-proceessed by the adhesive applicator.

16. The bookbinding apparatus according to claim 11, wherein: the adhesive applicator includes a container for storing hot-melt adhesive and an applicator roller means provided within the container; andthe container is supported on a frame of the bookbinding apparatus, free to move paralleling an edge of a sheet bundle in the binding position, and is provided with shifting means for reciprocatingly shifting the container.

17. An adhesive temperature control method in an adhesive applicator, for controlling to a predetermined temperature hot-melt adhesive, loaded into a container, with a heating means with which the container is equipped, the method comprising: an initial-temperature gauging step of gauging temperature of the adhesive when the applicator is turned on;a heating-mode defining step of selecting one of a plurality of heating modes in accordance with the adhesive temperature gauged in the initial-temperature gauging step; anda heating step of executing the heating mode selected in the heating-mode defining step; whereinthe heating modes are each constituted by a primary heating step of applying to the heating means predetermined electrical power corresponding to a first target temperature, to heat the container to a set temperature, anda secondary heating step of applying to the heating means predetermined electrical power corresponding to a second target temperature differing from the first target temperature, after a predetermined set period has elapsed after the container temperature has been gauged to have reached a predetermined temperature; andthe plurality of heating modes are defined by values whereby their respective first and second target temperatures and the set periods differ.

18. The adhesive temperature control method according to claim 17, wherein in the secondary heating step, after the container temperature has been gauged to have reached the predetermined temperature, the adhesive within the container is stirred with a stirring means with which the container is equipped.