CN113453485A

CN113453485A - Liquid cooling head device

Info

Publication number: CN113453485A
Application number: CN202011460418.2A
Authority: CN
Inventors: 陈建佑; 叶恬利; 林仁豪; 陈建安
Original assignee: Chunhong Electronic Technology Chongqing Co ltd
Current assignee: Chunhong Electronic Technology Chongqing Co ltd
Priority date: 2020-03-27
Filing date: 2020-12-11
Publication date: 2021-09-28
Also published as: TW202137863A; CN113518535A; CN213694682U; TWI738584B; CN213907271U; TWI765466B; TW202137864A

Abstract

A liquid cooling head device comprises a base, an upper cover, an inlet part, an outlet part and a water pump. The base comprises a flow guide channel, a first chamber and an opening, wherein the first chamber is communicated with the flow guide channel and the opening and is internally provided with a radiating fin module. The upper cover covers the base and forms a second chamber with the base. The inlet part is positioned on the base and communicated with the first chamber through the diversion channel. The outlet part is formed on the upper cover. The water pump includes a housing and a fan blade. The shell covers one surface of the upper cover, so that a third chamber is defined between the water pumping pump and the upper cover. The third chamber is communicated with the second chamber and the outlet part respectively. The fan blade is positioned in the third chamber, and the flow guide channel is positioned between the fan blade and the first chamber. Through the structure, the liquid cooling head device can achieve a good heat dissipation technical effect and is also beneficial to being applied to related computer equipment, a host or server equipment.

Description

Liquid cooling head device

Technical Field

The present disclosure relates to heat dissipation modules, and particularly to a liquid cooling head device.

Background

With the advancement and popularization of science and technology, various electronic devices or computer apparatuses have long become indispensable in daily life, such as notebook computers, desktop computers, network servers, and the like. Generally, the electronic components inside these products are heated during operation, and the high temperature is likely to cause damage to the components. Therefore, the heat dissipation mechanism is an important and necessary design for these electronic products. In addition to the general heat dissipation design using a fan to provide air flow for convection cooling or using a heat dissipation unit made of a special material for attachment to generate conduction cooling, a water cooling mechanism is also an effective and common heat dissipation design.

The principle of water-cooled heat dissipation is simply that a liquid (such as water or coolant) is generally used as a heat dissipation medium, and a water pump or a pump which operates continuously is used to form a continuous circulation in the applied system. The liquid flows in closed conduits that are distributed over the surface of various electronic components (e.g., central processing units) within the system. When a relatively low temperature fluid flows through these relatively high temperature electronic components, it absorbs its heat to slow the temperature rise. Then, the heat is released by the heat exchange between the pipeline and the outside or other heat dissipation mechanisms to reduce the temperature of the liquid, and the liquid returns to the system again for circulation and heat dissipation.

However, since the internal space of a general computer device, a host or a server device is limited, it can only be utilized by the space of the installed environment, and the water-cooled heat dissipation device needs to have the design of the inflow and outflow of the pipeline, so that the installation of the pipeline is relatively complicated. Therefore, how to design a water-cooling heat dissipation structure with good heat dissipation technical effect, and can give consideration to the whole pipeline configuration, reduce the occupied space so as to be convenient for setting in a narrow environment, and effectively complete the connection with other pipelines and avoid the occurrence of water leakage, is the main purpose of the development of the present disclosure.

Disclosure of Invention

An object of the present invention is to provide a liquid cooling head device, which solves the above mentioned difficulties of the prior art.

One embodiment of the present invention provides a liquid-cooled header apparatus. The liquid cooling head device comprises a base, a heat radiation fin module, an upper cover, an inlet part, an outlet part and a water pump. The base comprises a flow guide channel, a first chamber and at least one opening, wherein the first chamber is communicated with the flow guide channel and the opening respectively. The heat dissipation fin module is located in the first chamber. The upper cover covers one surface of the base, a second cavity is formed between the upper cover and the base, and the second cavity is communicated with the first cavity through the opening. The inlet part is positioned on the base and communicated with the first chamber through the diversion channel. The outlet part is formed on the upper cover. The water pump includes a housing and a fan blade. The shell covers one surface of the upper cover back to the base, so that a third chamber is defined between the shell and the upper cover. The third chamber is communicated with the second chamber and the outlet part respectively. The fan blade is positioned in the third chamber, and the flow guide channel is positioned between the fan blade and the first chamber. Thus, when a working fluid is sent into the first chamber from the inlet part and flows through the second chamber, the fan blades send the working fluid in the second chamber out of the outlet part through the third chamber.

According to one or more embodiments of the present invention, in the liquid cooling head apparatus, the base includes a heat conductive substrate, a lower cover and an elastic dome. The radiating fin module is positioned on one surface of the heat conducting substrate. The lower cover is combined to the heat-conducting substrate. The elastic dome is clamped between the heat conducting substrate and the lower cover. The elastic air guide sleeve comprises a first through opening and at least one second through opening. The first through opening is communicated with the flow guide channel and the first chamber, and the second through opening is communicated with the opening and the first chamber.

According to one or more embodiments of the present invention, in the liquid cooling head device, there are two openings and two second through holes, and the openings are aligned with and communicated with the second through holes respectively, and the first through hole is located between the second through holes and at a central position of the lower cover.

According to one or more embodiments of the present invention, in the liquid cooling head device, the housing has an electromechanical cavity and a lower groove. The lower groove is positioned on one surface of the shell, and the electromechanical cavity is positioned inside the shell. The upper cover is provided with an upper groove, the upper groove and the lower groove jointly form a third chamber, and the third chamber is hermetically isolated from the electromechanical cavity.

According to one or more embodiments of the present invention, in the liquid cooling head apparatus, the water pump further includes a stator, a rotor, a shaft, and a circuit board. The stator is located within the electromechanical cavity. The rotor is located in the third chamber and fixedly connected with the fan blades. The shaft rod penetrates through the rotor and the fan blades and is connected with the upper cover to drive the rotor to rotate so as to drive the fan blades to rotate.

According to one or more embodiments of the present invention, in the liquid cooling head apparatus, the rotor is a magnet, and the stator is one of a silicon steel sheet, a magnet and an electromagnet.

According to one or more embodiments of the present invention, in the liquid cooling head device, the heat dissipation fin module includes a plurality of fin portions, and a gap is formed between any two adjacent fin portions. The elastic air guide cover comprises a flexible cushion body and a plurality of positioning blocks, the positioning blocks are arranged on one surface of the flexible cushion body facing the heat conduction substrate at intervals, and each positioning block extends into one of the gaps and is used for fixing the elastic air guide cover on the heat conduction substrate.

According to one or more embodiments of the present invention, in the liquid cooling head device, a surface of the lower cover facing away from the elastic dome has a recessed portion, the opening is formed in the recessed portion, and a surface of the lower cover facing the heat conducting substrate has at least one annular recess surrounding the opening.

According to one or more embodiments of the present invention, in the liquid cooling head device, the elastic dome further includes at least one annular protrusion, and the annular protrusion is protruded from a surface of the flexible pad facing away from the heat conductive substrate and inserted into the annular recess.

According to one or more embodiments of the present invention, in the liquid cooling head device, the elastic flow guiding cover comprises a flexible material.

Thus, through the above-mentioned architecture of the embodiments, the present invention not only can achieve a good heat dissipation effect, but also is beneficial to be applied to related computer equipment, hosts or server equipment.

The foregoing is merely illustrative of the problems, solutions to problems, and technical effects that can be produced by the present invention, and the detailed description of the present invention will be described in detail in the following detailed description and the related drawings.

Drawings

In order to make the aforementioned and other objects, features, and advantages of the invention, as well as others which will become apparent, reference is made to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1A is a perspective view of a liquid cooling header assembly;

FIG. 1B is an exploded view of a liquid cold head apparatus;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1A;

fig. 3A and 3B are partial perspective views of the liquid-cooled header assembly, showing the process of the working fluid entering the guide channel of the lower cover from the outside;

FIGS. 4A and 4B are sectional and partial perspective views of the fluid-cooled header assembly, illustrating the process of the working fluid after flowing through the flexible pod from the lower cover, through the third chamber, and into the second chamber;

FIG. 4C is a perspective view of a thermally conductive substrate of the liquid-cooled head apparatus;

FIGS. 5A and 5B are sectional views and partial perspective views of the liquid-cooled header assembly, showing the process of working fluid entering the second chamber and then flowing into the first chamber; and

fig. 6A and 6B are a cross-sectional view and a partial perspective view of the liquid-cooled head device, showing how the working fluid is guided by the fan blade after entering the first chamber, and finally discharged out of the liquid-cooled head device.

Description of reference numerals:

2-2: section line

6: liquid cooling head device

61: water pump

611: shell body

6111: electromechanical cavity

6112: lower groove

612: stator

613: rotor

614: axle bar

615: fan blade

62: upper cover

62A: first side

62B: second side

621: shaft rod fixing frame

622: opening holes

623: upper groove

624: outlet section

625: opening of the container

63: lower cover

63A: first side

63B: second side

630: base seat

631: inlet section

632. 633: opening of the container

634: diversion channel

635: concave part

636: annular recess

64: elastic air guide sleeve

64A: first side

64B: second side

640: flexible cushion

641: the first through hole

642. 643: second through hole

645: locating block

646: annular convex part

65: heat-conducting substrate

65A: first side

65B: second side

651: radiating fin module

6511: fin part

6512: gap

652: boss structure

66A: third chamber

66B: second chamber

66C: the first chamber

D1-D7: direction of rotation

Detailed Description

In the following description, for purposes of explanation, numerous implementation details are set forth in order to provide a thorough understanding of the various embodiments of the invention. It should be understood, however, that these implementation details are not to be interpreted as limiting the invention. That is, these implementation details are not necessary in the embodiments of the present invention. In addition, some conventional structures and elements are shown in the drawings in a simple schematic manner for the sake of simplifying the drawings.

Referring to fig. 1A, fig. 1B and fig. 2, fig. 1A shows a perspective view of a liquid-cooled head device 6 according to an embodiment of the present invention, fig. 1B is an exploded view of fig. 1A, and fig. 2 is a cross-sectional view of fig. 1A along a section line 2-2.

In the present embodiment, the liquid-cooled head device 6 mainly includes a water pump 61, an upper cover 62 and a base 630, and the water pump 61, the upper cover 62 and the base 630 are assembled from top to bottom to stack the liquid-cooled head device 6. The base 630 includes a flow guide channel 634, a first chamber 66C and two

openings

632, 633. The first chamber 66C communicates with the guide channel 634 and the two

openings

632 and 633, respectively. A cooling fin module 651 is disposed within the first chamber 66C. The upper cover 62 includes a first side 62A and a second side 62B opposite to each other. The second side 62B of the cover 62 covers the top surface of the base 630 and forms a second chamber 66B with the base 630. The second chamber 66B communicates with the first chamber 66C through the

openings

632, 633. The base 630 is provided with an inlet 631. The inlet port 631 communicates with the first chamber 66C through the guide channel 634. An outlet portion 624 is disposed on the first side 62A of the cover 62. The water pump 61 covers the upper cover 62 to define a third chamber 66A therebetween.

More specifically, the base 630 includes a lower cover 63, an elastic dome 64 and a heat conductive substrate 65. The heat conductive substrate 65 includes a first side 65A and a second side 65B opposite to each other. The cooling fin module 651 is located on the first side 65A of the thermally conductive substrate 65. The lower cover 63 includes a first side 63A and a second side 63B opposite to each other, and the second side 63B of the lower cover 63 is combined to the heat conductive substrate 65. The inlet 631 and the

openings

632 and 633 respectively penetrate through the first side 63A and the second side 63B of the lower cover 63. The elastic dome 64 is sandwiched between the first side 63A of the heat conductive substrate 65 and the second side 63B of the lower cover 63.

The flexible dome 64 includes a flexible pad 640, a first opening 641, and two

second openings

642, 643. The flexible pad 640 includes a first side 64A and a second side 64B opposite to each other. The first opening 641 and the

second openings

642, 643 both penetrate the first side 64A and the second side 64B of the flexible pad 640. The first opening 641 connects the flow guide channel 634 with the first chamber 66C, the

second openings

642, 643 are aligned with and connect the

openings

632, 633 respectively, and the

second openings

642, 643 also connect the first chamber 66C together. In the present embodiment, but not limited thereto, the first through opening 641 is located between the second through

openings

642 and 643 and is located at about the center of the lower cover 63. In addition, the elastic dome 64 further includes a plurality of positioning blocks 645 and two annular protrusions 646. The positioning blocks 645 are disposed at intervals on the second side 64B of the flexible pad 640. Each annular protrusion 646 protrudes from a surface of the flexible pad 640 facing away from the heat conductive substrate 65 (i.e., the second side 64B of the flexible pad 640), and surrounds the

second opening

642 or 643.

The water pump 61 includes a housing 611, a stator 612, a circuit board (not shown), a rotor 613, a shaft 614 and a fan blade 615. The housing 611 covers a side of the upper cover 62 opposite the base 630 such that the housing 611 and the upper cover 62 define the third chamber 66A therebetween. The third chamber 66A communicates with the second chamber 66B and the outlet portion 624, respectively. The housing 611 forms an electromechanical cavity 6111, and the electromechanical cavity 6111 is a space isolated from the working fluid, and houses the circuit board and the stator 612 therein. The stator 612 is a magnetic element, such as a silicon steel sheet, a magnet or an electromagnet, and is electrically connected to the circuit board. Rotor 613 is coupled to fan blades 615 and is located within the active volume (outside of electromechanical chamber 6111) through which the working fluid flows. The rotor 613 employs a magnetic element such as a magnet. The fan blade 615 is located in the upper recess 623 of the upper cover 62, and the guide channel 634 is located between the fan blade 615 and the first chamber 66C. Under the combined action of the circuit board, the stator 612 and the rotor 613, the fan blade 615 can be driven to rotate, thereby guiding the movement of the working fluid. In addition, the shaft 614 passes through the rotor 613 and the fan blade 615 and is mounted on a shaft holder 621 of the upper cover 62 to prevent the rotor 613 and the fan blade 615 from swinging or deviating from the rotating shaft when rotating.

The upper cover 62 is assembled with the housing 611 of the water pump 61 to define the third chamber 66A, and the second side 62B of the upper cover 62 faces the lower cover 63 and is assembled with the first side 63A of the lower cover 63. In this embodiment, the assembling means is a screw fastening method, and two different components are assembled together through corresponding screw holes and screws. More specifically, one face of the housing 611 has a lower groove 6112. The upper cover 62 has an upper recess 623, and the lower recess 6112 and the upper recess 623 together form the third chamber 66A.

In addition, the upper cover 62 forms a shaft holder 621 on the first side 62A, and at least one opening 622 is formed below the bottom of the shaft holder 621. Furthermore, the upper cover 62 forms an upper groove 623 and an outlet portion 624 (such as a drain line) around the shaft bar holder 621, and the upper groove 623 is a portion of the third chamber 66A and corresponds to the bottom of the fan blade 615 in size, so as to accommodate the bottom of the fan blade 615 therein. The outlet portion 624 is connected to the upper recess 623, and is used for discharging the working fluid from the upper recess 623 to the outside of the liquid cooling head device 6.

The first side 63A of the lower cover 63 corresponds to the second side 62B of the upper cover 62, and the two are assembled together to define a second chamber 66B, and the second chamber 66B and the third chamber 66A are connected to each other through the opening 622. The second side 63B of the lower cover 63 faces the elastic pod 64 and the heat conductive substrate 65, and the second side 63B of the lower cover 63 is assembled with the first side 65A of the heat conductive substrate 65, while the elastic pod 64 is sandwiched between the lower cover 63 and the heat conductive substrate 65. In addition, the flexible dome 64 and the heat conductive substrate 65 together define a first chamber 66C. The elastic dome 64 can guide the flow of the working fluid, and can be made of a flexible and deformable rubber material, so that the elastic dome has the functions of a waterproof gasket and an O-ring (O-ring), and can fill up a gap between the lower cover 63 and the heat conductive substrate 65 and prevent liquid leakage.

One of the openings 632 of the lower cover 63 directly corresponds to one of the

second openings

642 or 643 of the elastic air guide sleeve 64 in the vertical direction, and the opening 633 of the lower cover 63 directly aligns with the opening 643 of the elastic air guide sleeve 64 in the vertical direction. The side of the lower cover 63 facing away from the elastic airflow guiding cover 64 (i.e. the first side 63A) has a recess 635, and the openings 632 are formed in the recess 635. The side of the lower cover 63 facing the heat conductive substrate 65 (i.e., the second side 63B) has a two-ring-shaped recess 636. Each annular recess 636 surrounds one of the openings 632. Each annular protrusion 646 is inserted into an annular recess 636. In addition, the aforementioned guiding groove 634 is formed on the second side 63B of the bottom cover 63 (please refer to fig. 3B), and the guiding groove 634 is responsible for communicating the inlet portion 631 of the bottom cover 63 with the first through hole 641 of the elastic guiding cover 64 after the bottom cover 63 and the elastic guiding cover 64 are assembled with the heat conducting substrate 65. Conversely, when the flexible pod 64 is removed away from the lower cover 63, the annular protrusions 646 are drawn away from the corresponding annular recesses 636.

The heat sink fin module 651 is formed on the first side 65A of the heat conductive substrate 65. The cooling fin module 651 includes a plurality of fin portions 6511. Each fin portion 6511 includes a plurality of fins arranged in parallel (not shown). A gap 6512 is provided between any two adjacent fin portions 6511. When the flexible pod 64 covers the first side 65A of the heat conductive substrate 65, each positioning block 645 of the flexible pod 64 extends into one of the gaps 6512 to fix the flexible pod 64 on the heat conductive substrate 65 and guide the working fluid into the fin portions 6511, so that the fins take away the heat energy absorbed by the working fluid. Conversely, when the flexible pod 64 is removed away from the heat conductive substrate 65, the positioning blocks 645 are respectively pulled out of the corresponding gaps 6512. It is understood that the third cavity 66A defined by the flexible pod 64 and the thermally conductive substrate 65 is mostly filled by the heat sink fin module 651 and the gap 6512.

The second side 65B of the heat conductive substrate 65 may form an outwardly protruding boss 652, and the boss 652 is in direct thermal contact with the heat source, or in indirect thermal contact with the heat source through a heat conductive paste or a heat conductive sheet. Next, the flow direction of the working fluid in the liquid-cooling head device of the present disclosure will be described, and the corresponding structure of each component of the liquid-cooling head device will be correspondingly displayed.

Fig. 3A and 3B are partial perspective views of the liquid cooling head device 6 (including only the water pump 61, the upper cover 62 and the lower cover 63), and show the process of the working fluid entering the guide channel 634 of the lower cover 63 from the outside. Referring first to fig. 3A, the working fluid enters the liquid-cooled head device 6 from the opening 625 of the upper cover 62 along the direction D1 and passes through the inlet portion 631 of the lower cover 63. Then, as shown in fig. 3B, the working fluid flows along the guide channel 634 with an arc shape along the direction D2 toward the central region of the second side 63B of the lower cover 63, i.e., above the first opening 641 of the elastic guide cover 64 (fig. 1B).

Fig. 4A and 4B are a sectional view and a partial perspective view (only including the water pump 61, the upper cover 62, the lower cover 63 and the elastic dome 64) of the liquid-cooled head device 6, respectively, and show the process of the working fluid after flowing through the elastic dome 64 from the lower cover 63, passing through the first chamber 66C and entering the second chamber 66B. Fig. 4C is a perspective view of the heat conductive substrate 65 of the liquid-cooled head device 6, wherein the positioning block 645 in the gap 6512 is shown by a dotted line. As shown in fig. 4A to 4C, after passing through the first opening 641 of the flexible pod 64, the working fluid enters the first chamber 66C downward along the direction D3, and then passes through the gap 6512 between the fin portions 6511 along the direction D4, and then converges toward the two

second openings

642, 643 of the flexible pod 64 and prepares to enter the second chamber 66B upward. (FIGS. 4A and 4B)

Fig. 5A and 5B are a sectional view and a partial perspective view (only including the water pump 61 and the upper cover 62) of the liquid-cooling head device 6, which correspondingly show the process of the working fluid entering the second chamber 66B and then flowing to the third chamber 66A in a concentrated manner. After passing through the two

second openings

642, 643 of the flexible pod 64, the working fluid passes through the

openings

632, 633 of the lower cover 63 and enters the second chamber 66B, where the working fluid is rearranged in the space and then collected along the direction D5 toward the opening 622 of the upper cover 62 to enter the third chamber 66A.

Fig. 6A and 6B are a cross-sectional view and a partial perspective view (only including the top cover 62 and a portion of the fan blade 615) of the liquid cooling head device 6, which correspondingly show how the working fluid is guided by the fan blade 615 after entering the third chamber 66A, and finally discharged out of the liquid cooling head device 6. After entering the third chamber 66A from below the opening 622 of the upper cover 62, the working fluid is sucked into the space between the blades of the fan blade 615 along the direction D6, and when the fan blade 615 rotates to the vicinity of the outlet portion 624, the working fluid can pass through the outlet portion 624 and be thrown out of the liquid cooling head device 6 along the direction D7, and further be transmitted to another cooling device, such as a water cooling drain, for cooling.

Finally, the above-described embodiments are not intended to limit the invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims

1. A liquid-cooled head apparatus, comprising:

a base, including a diversion channel, a first chamber and at least one opening, the first chamber connects the diversion channel and the opening separately;

a heat radiation fin module located in the first chamber;

the upper cover covers one surface of the base, a second cavity is formed between the upper cover and the base, and the second cavity is communicated with the first cavity through the opening;

the inlet part is positioned on the base and communicated with the first chamber through the flow guide channel;

an outlet part formed on the upper cover; and

a water pump, comprising:

a shell covering one side of the upper cover back to the base, so that a third chamber is defined between the shell and the upper cover, and the third chamber is respectively communicated with the second chamber and the outlet part; and

a fan blade located in the third chamber, and the flow guide channel is located between the fan blade and the first chamber,

when a working fluid is sent into the first chamber from the inlet part and flows through the second chamber, the fan blade sends the working fluid in the second chamber out of the outlet part through the third chamber.

2. The liquid cold head apparatus of claim 1, wherein the base comprises:

a heat conducting substrate, wherein the heat radiating fin module is positioned on one surface of the heat conducting substrate;

a lower cover assembled to the heat conductive substrate; and

an elastic air guide sleeve clamped between the heat conducting substrate and the lower cover,

the elastic flow guide cover comprises a first through opening and at least one second through opening, the first through opening is communicated with the flow guide channel and the first chamber, and the second through opening is communicated with the opening and the first chamber.

3. The liquid cooling head apparatus of claim 2, wherein there are two openings and two second through holes, and the openings are aligned with and connected to the second through holes, respectively, and the first through hole is located between the second through holes and at a central position of the lower cover.

4. The liquid cold head apparatus of claim 1, wherein said housing has an electromechanical chamber and a lower groove, said lower groove being located on a side of said housing, said electromechanical chamber being located inside said housing; and

the upper cover is provided with an upper groove, the upper groove and the lower groove jointly form the third chamber, and the third chamber is hermetically isolated from the electromechanical chamber.

5. The liquid cold head apparatus of claim 4, wherein said water pump further comprises:

a stator located in the electromechanical cavity;

a rotor, which is positioned in the third chamber and fixedly connected with the fan blade;

a shaft rod passing through the rotor and the fan blade and connected with the upper cover; and

a circuit board for driving the rotor to rotate so as to drive the fan blades to rotate.

6. The liquid cooling head apparatus of claim 5, wherein the rotor is a magnet, and the stator is one of a silicon steel plate, a magnet and an electromagnet.

7. The liquid cold head apparatus of claim 2, wherein said heat sink fin module comprises a plurality of fin portions, any two adjacent ones of said plurality of fin portions having a gap therebetween; and

the elastic air guide sleeve comprises a flexible cushion body and a plurality of positioning blocks, the positioning blocks are arranged on one surface of the flexible cushion body facing the heat conduction substrate at intervals, and each positioning block extends into one of the gaps to fix the elastic air guide sleeve on the heat conduction substrate.

8. The liquid cooling head apparatus of claim 7, wherein a surface of the lower cover facing away from the flexible dome has a recess, the opening is formed in the recess, and a surface of the lower cover facing the heat conductive substrate has at least one annular recess surrounding the opening.

9. The liquid cooling head device of claim 8, wherein the flexible dome further comprises at least one annular protrusion protruding from a surface of the flexible pad opposite to the heat conductive substrate and inserted into the annular recess.

10. The liquid cooling head apparatus of claim 2, wherein the flexible pod comprises a flexible material.