PULP SUCTION MOLD FOR MOLDED PULP FORMING MACHINE

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Taiwanese Invention Patent Application No. 113103669, filed on Jan. 31, 2024, and incorporated by reference herein in its entirety.

FIELD

The present disclosure relates to a pulp suction mold, and more particularly to a pulp suction mold for a molded pulp forming machine.

BACKGROUND

A molded pulp manufacturing mold, as disclosed in Chinese Patent Publication No. CN219752850U, includes an upper mold and a lower mold cooperating with each other to define a bottle-shaped cavity for receiving pulp. The upper mold includes a plurality of first negative pressure holes communicating with the bottle-shaped cavity. The lower mold includes a plurality of second negative pressure holes communicating with the bottle-shaped cavity. The first and second negative pressure holes are used for air in the bottle-shaped cavity and liquid in the pulp to be sucked and discharged. The fibers in the pulp are adsorbed on walls of the upper and lower molds to form a wet paper bottle model.

Since the first and second negative pressure holes are directly connected to a vacuum pump, there may be a situation where suction force is small and unstable without a buffer space. Thus, the paper bottle model may have technical problems, such as uneven thickness or thickness that does not meet standard.

SUMMARY

Therefore, an object of the present disclosure is to provide a pulp suction mold for a molded pulp forming machine that can alleviate at least one of the drawbacks of the prior art.

According to this disclosure, the pulp suction mold for the molded pulp forming machine includes a lower mold and an upper mold. The molded pulp forming machine includes a pulp tank for containing pulp. The pulp suction mold is configured to slidably move in and out of the pulp tank.

The upper mold cooperates with the lower mold to define at least one mold cavity for receiving the pulp and at least one mold opening communicating the at least one mold cavity with the outside. The upper mold defines an upper air chamber located above the at least one mold cavity, and is formed with a plurality of upper passage holes communicating with the at least one mold cavity and the upper air chamber, and an upper connecting port communicating the upper air chamber with the outside and located adjacent to an end of the at least one mold cavity in an up-down direction.

The upper connecting port is configured for suction airflow to suck the pulp in the pulp tank into the at least one mold cavity through the at least one mold opening and to suck air in the at least one mold cavity and liquid in the pulp into the upper air chamber through the upper passage holes and then discharge out of the upper air chamber through the upper connecting port.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings. It is noted that various features may not be drawn to scale.

FIG. 1 is a fragmentary front view of a molded pulp forming machine incorporating a pulp suction mold according to an embodiment of the present disclosure.

FIG. 2 is a top view of the embodiment.

FIG. 3 is a sectional view taken along line III-III of FIG. 2.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 2.

FIG. 5 is an enlarged fragmentary sectional view of FIG. 4.

FIG. 6 is a view similar to FIG. 3, but with a lower wall of a lower mold having a V-shaped cross section and a lower wall of an upper mold having an inverted V-shaped cross section.

FIG. 7 is a view similar to FIG. 4, but with a lower wall of a lower mold having a V-shaped cross section and a lower wall of an upper mold having an inverted V-shaped cross section.

DETAILED DESCRIPTION

Referring to FIGS. 1 to 5, a pulp suction mold according to an embodiment of the present disclosure is suitable to be mounted on a molded pulp forming machine 1. The molded pulp forming machine 1 includes a machine frame unit 11, a pulp tank 12 mounted on the machine frame unit 11 for containing pulp, and a vacuum pump 13 mounted on the machine frame unit 11 for generating suction airflow. The pulp suction mold of this embodiment is mounted on and slidable along two parallel rods of the machine frame unit 11 in an up-down direction (Z) relative to the pulp tank 12, and includes a lower mold 2 and an upper mold 3.

The lower mold 2 includes an upper wall 22 having a lower mold surface 21 that faces the upper mold 3, and a lower wall 23 opposite to and cooperating with the upper wall 22 to define a lower air chamber 20. The lower mold 2 is formed with a plurality of lower passage holes 24 extending from the lower mold surface 21 toward and communicating with the lower air chamber 20, and a lower connecting port 25 located below the lower air chamber 20 and communicating the lower air chamber 20 with the outside. In this embodiment, each of the upper and lower walls 22, 23 is flat, and the lower connecting port 25 is configured to be connected to the vacuum pump 13.

The upper mold 3 includes an upper wall 32, a lower wall 33 opposite to the upper wall 32 and having an upper mold surface 31 that faces the lower mold surface 21 and that cooperates with the same to define a plurality of mold cavities 301 and a plurality of mold openings 302, and a peripheral wall 36 between the upper and lower walls 32, 33. The upper, lower and peripheral walls 32, 33, 36 cooperatively define an upper air chamber 303. The upper wall 32 is distal to the mold cavities 301. The upper mold 3 is formed with a plurality of upper passage holes 34 extending from the upper mold surface 31 toward and communicating with the upper air chamber 303, and an upper connecting port 35 formed in the peripheral wall 36 for communicating the upper air chamber 303 with the outside and extending in a horizontal direction (Y) transverse to the up-down direction (Z) (see FIG. 4). The mold cavities 301 are configured to receive the pulp, and communicate with the lower air chamber 20 through the lower passage holes 24 and with the upper air chamber 303 through the upper passage holes 34. Each mold cavity 301 communicates with the outside through a respective one of the mold openings 302. In this embodiment, each of the upper and lower walls 32, 33 is flat, and the upper connecting port 35 is also configured to be connected to the vacuum pump 13. Furthermore, the upper connecting port 35 is close to the lower wall 33 in the up-down direction (Z). That is, as shown in FIG. 5, the upper connecting port 35 is spaced apart from the upper wall 32 by a first distance (d1), and is spaced apart from the lower wall 33 by a second distance (d2) that is smaller than the first distance (d1). A ratio between the first distance (d1) and the second distance (d2) ranges from 9:1 to 6:4. In this embodiment, the ratio between the first distance (d1) and the second distance (d2) is 8:2.

When the vacuum pump 13 is activated to suck air in the mold cavities 301 through the upper and lower connecting ports 35, 25 and to form a suction airflow, the pulp inside the pulp tank 12 is sucked to enter the mold cavities 301 through the respective mold openings 302. At this time, the air in the mold cavities 301 and liquid in the pulp not only are sucked into the upper air chamber 303 through the upper passage holes 34 and then discharge out of the upper air chamber 303 through the upper connecting port 35, but also are sucked into the lower air chamber 20 through the lower passage holes 24 and then discharge out of the lower air chamber 20 through the lower connecting port 25. Simultaneously, the paper fibers in the pulp are adsorbed to the upper and lower mold surfaces 31, 21, and are shaped into a plurality of blanks 4 according to the shapes of the mold cavities 301.

It should be noted herein that through the suction airflow generated by the vacuum pump 13 for adsorbing the paper fibers in the pulp to the upper mold surface 31 of the upper mold 3 and the lower mold surface 21 of the lower mold 2 is a common technology and is not a technical feature of this disclosure, and those with ordinary skilled in the art can deduce the expanded details based on the above description, so that a further description thereof is omitted herein.

A characterizing feature of this disclosure resides in that the volume of each of the upper and lower air chambers 303, 20 can increase the flow rate and the suction force of the suction airflow. Furthermore, by forming the upper connecting port 35 adjacent to the mold cavities 301 instead of above the upper air chamber 303, the liquid in the pulp can be discharged immediately out of the upper air chamber 303 through the upper connecting port 35 after entering the upper air chamber 303. Apart from being able to discharge the liquid without waiting for it to fill the upper air chamber 303, this disclosure can also avoid a situation in which the suction force can be affected due to the filling of the upper air chamber 303 with the liquid.

In addition, because the ratio between the first distance (d1) and the second distance (d2) of this embodiment is 8:2, the liquid in the pulp can enter the upper air chamber 303 quickly and in large amounts without being limited by the volume of the upper air chamber 303, and when a height of the liquid in the up-down direction (Z) is accumulated to approximately equal to ¼ of the height of the upper air chamber 303 in the up-down direction (Z), the liquid can be drawn out of the upper air chamber 303 through the upper connecting port 35 which is connected to the vacuum pump 13.

It should be further noted that the ratio between the first distance (d1) and the second distance (d2) is not limited to 8:2. In other variations of this embodiment, the ratio between the first distance (d1) and the second distance (d2) may be 9:1, 7:3, or 6:4. Furthermore, the number of the mold cavities 301 is not limited to multiple. In other variations of this embodiment, the number of the mold cavity 301 may be one for forming one blank 4 or one row of multiple mold cavities 301 for forming a plurality of blanks 4 in one row. Moreover, the number of the upper connecting port 35 is not limited to only one, and may be two or more than two in other variations of this embodiment.

It is worth to note herein that the lower wall 23 of the lower mold 2 is not limited to being flat. In other variations of this embodiment, as shown in FIGS. 6 and 7, the lower wall 23 may have a generally V-shaped cross section. Through this, the liquid entering the lower air chamber 20 can flow more quickly and more concentratedly toward the lower connecting port 25 and out of the lower air chamber 20. Similarly, the lower wall 33 of the upper mold 3 is not limited to being flat. In other variations of this embodiment, as shown in FIGS. 6 and 7, the lower wall 33 may have a generally inverted V-shaped cross section. Through this, the liquid entering the upper air chamber 303 can flow more quickly and more concentratedly toward the upper connecting port 35 and out of the upper air chamber 303.

Through the above description, the advantages of this disclosure can be summarized as follows:

• • 1. This disclosure can increase the flow rate and the suction force of the suction airflow through the volumes of the upper and lower air chambers 303, 20, thereby enhancing the suction efficiency thereof.
  • 2. With the upper air chamber 303 and the lower air chamber 20 serving as buffer spaces for accommodating the air in the mold cavities 301 and the liquid in the pulp sucked by the suction airflow which is generated by the vacuum pump 13, and with the upper connecting port 35 being designed adjacent to the mold cavities 301, the liquid in the pulp can be quickly discharged out of the upper air chamber 303 through the upper connecting port 35 after entering the upper air chamber 303, so that not only the stability during suction can be improved, but also the suction efficiency can be enhanced.

In the description above, for the purposes of explanation, numerous

specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects; such does not mean that every one of these features needs to be practiced with the presence of all the other features. In other words, in any described embodiment, when implementation of one or more features or specific details does not affect implementation of another one or more features or specific details, said one or more features may be singled out and practiced alone without said another one or more features or specific details. It should be further noted that one or more features or specific details from one embodiment may be practiced together with one or more features or specific details from another embodiment, where appropriate, in the practice of the disclosure.

While the disclosure has been described in connection with what is considered the exemplary embodiment, it is understood that this disclosure is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.