CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a U.S. National stage application of International Patent Application No. PCT/JP2017/028734, filed on Aug. 8, 2017, which claims priority under 35 U.S.C. § 119(a) to Japanese Patent Application No. 2016-169127, filed in Japan on Aug. 31, 2016. The entire disclosure of Japanese Patent Application No. 2016-169127 is hereby incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a sheet manufacturing apparatus.

BACKGROUND ART

There is known a sheet manufacturing apparatus that is configured to include a defibration unit that defibrates a substance to be defibrated in an atmosphere, a mixer that mixes defibrated substance and an additive containing a resin in an atmosphere, a humidity control unit that controls humidity of a mixture, and a heating unit that heats the humidity-controlled mixture (for example, see Japanese Unexamined Patent Application Publication No. 2015-137437). In Japanese Unexamined Patent Application Publication No. 2015-137437, the humidity control of the mixture induces an efficient hydrogen bond between fibers of a sheet when the heating unit performs heating.

Incidentally, in a type of sheet manufacturing apparatus, there is a concern that fragmented raw materials such as defibrated substances will be attached to portions due to an influence of charging and, thus, will remain or a concern that the raw materials will be attached to each other. In order to avoid the remaining and attachment, it is conceivable to employ a method in which a humidity control unit in the related art humidifies the fragmented raw materials. However, in this case, there is a concern that condensation will occur or it is not possible to sufficiently suppress remaining and attachment.

SUMMARY

In this respect, an object of the present invention is to appropriately humidify both a raw material that is caused to remain or be attached due to an influence of charging and a web obtained by accumulating defibrated substances.

In order to achieve the object, a sheet manufacturing apparatus of the present invention includes: a rough crushing unit that roughly crushes a raw material containing fibers; a defibration unit that defibrates the raw material roughly crushed by the rough crushing unit, in a gas atmosphere; a web former that accumulates defibrated substances obtained through a defibrating process performed by the defibration unit and forms a web; a sheet former that forms a sheet of the web; a vaporization-type humidifier that humidifies a space in which the raw material is roughly crushed by the rough crushing unit; and a mist-type humidifier that humidifies the web that is formed by the web former.

According to the present invention, it is possible to humidify a space through which fragmented raw materials pass, by the vaporization-type humidifier, while an occurrence of condensation is suppressed, and it is possible to suppress remaining of the raw material or attachment of the raw materials to each other due to an influence of charging. In addition, it is possible to humidify the web obtained by the accumulation of the defibrated substances, by the mist-type humidifier, without depending on a saturated steam amount of air. Hence, it is possible to appropriately humidify both the raw materials that are caused to remain or be attached to each other due to the influence of charging and the web obtained by the accumulation of the defibrated substances.

In addition, in the present invention, the vaporization-type humidifier humidifies a space in which the defibrated substances are accumulated.

According to the present invention, it is possible to suppress remaining of the fragmented raw materials in a space of accumulation or attachment of the raw materials to each other due to the influence of charging.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a separation unit that has a separation belt, on which the defibrated substances are accumulated, and separates matter to be removed, which is not used in the sheet, from the defibrated substances. The vaporization-type humidifier humidifies a space in which the defibrated substances drop to the separation belt so as to be accumulated. The mist-type humidifier humidifies accumulated substances accumulated on the separation belt.

According to the present invention, it is possible to suppress remaining or attachment of the raw materials to each other due to the influence of charging in the fragmented raw materials that configure the defibrated substances, and it is possible to perform humidification to the extent that the accumulated substances accumulated on the separation belt do not adhere to the separation belt.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a dust collecting unit that traps the matter to be removed, which has been separated by the separation unit. Air having passed through the defibration unit, the separation unit, and the dust collecting unit, in this order, is introduced as humidifying target air to the vaporization-type humidifier.

According to the present invention, since the air that has passed through the defibration unit, the separation unit, and the dust collecting unit, in this order, is humidified by the vaporization-type humidifier so as to be supplied to a space in which the raw material positioned upstream is roughly crushed, it is possible to use the air that has been used in manufacture of the sheet so as to humidify spaces of portions.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a division unit that divides the accumulated substances accumulated on the separation belt. The vaporization-type humidifier humidifies a space in which the division unit divides the accumulated substances.

According to the present invention, it is possible to suppress remaining of the accumulated substances or attachment of the accumulated substances to each other due to the influence of charging in the space in which the accumulated substances accumulated on the separation belt are divided.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a mixer that mixes a resin and defibrated substances that configure a subdivided body divided by the division unit. The web former accumulates mixtures mixed by the mixer and forms a web.

According to the present invention, since it is possible to suppress remaining or attachment of the defibrated substances, it is possible to appropriately perform mixing with the resin, and it is possible to appropriately form the web with the mixed mixture.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a cutter that cuts the sheet formed by the sheet former. The vaporization-type humidifier humidifies a space in which the web is conveyed from the web former and a space including the cutter.

According to the present invention, it is possible to suppress adhesion of the web, adhesion of the sheet to a cut piece, or the like.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a water tank that stores water. Water is supplied from the water tank to the vaporization-type humidifier and the mist-type humidifier.

According to the present invention, it is possible to combine the tanks that supply water to the vaporization-type humidifier and the mist-type humidifier, and thus it is advantageous in a reduction in the number of components and a reduction in size of the sheet manufacturing apparatus.

In addition, in the present invention, the sheet manufacturing apparatus further includes: a control unit that controls water supply to the vaporization-type humidifier and the mist-type humidifier. The control unit controls, as a water supply control, water supply to the water tank at a time of starting up and water supply to each humidifier from the water tank such that an amount of water equal to or larger than a predetermined amount is stored in the vaporization-type humidifier and the mist-type humidifier in a time from the starting up to an operation stop.

According to the present invention, control by the control unit enables water to be supplied to the water tank at the time of starting up and the humidifiers to continue humidification by using water supplied at the time of starting up.

In addition, in the present invention, the control unit controls, as a water discharge control at a time of an apparatus stop, water discharge to the water tank from the vaporization-type humidifier and the mist-type humidifier and water discharge from the water tank.

According to the present invention, the control by the control unit enables water to be discharged to the water tank from the humidifiers and water to be discharged from the water tank at the time of apparatus stop.

