Gas stove

Abstract

This invention provides a gas stove, belonging to the field of kitchen appliance technology. The gas stove includes a first burner and a second burner. The first burner includes a first mounting base and a first burner head, which is rotatably connected to the first mounting base. The second burner includes a second mounting base and a second burner head, which is fixedly connected to the second mounting base. A channel is provided on the side of the second burner head, communicating with the center of the second burner head. The first burner head can pass through the channel, and at least a portion of it is positioned at the center of the second burner head. This invention allows the first and second burner heads to be stacked by horizontal rotation of the first burner, facilitating diverse choices for users based on their cooking needs and improving the user experience.

Description

Technical Field

[0001] This invention relates to the field of kitchen appliance technology, and in particular to a gas stove. Background Technology

[0002] As living standards improve, people have increasingly higher demands for the adjustable range of gas stove power (firepower). They not only want even heat distribution, but also concentrated low heat and the ability to stir-fry over high heat. However, the power of existing gas stoves is fixed and cannot meet different cooking needs simultaneously. Summary of the Invention

[0003] The purpose of this invention is to provide a gas stove in which the first burner can be rotated horizontally to stack the first burner and the second burner, forming multiple firepower zones, allowing users to make diverse choices according to their cooking needs and improving the user experience.

[0004] To achieve the objectives of this invention, the following technical solution is adopted:

[0005] According to a first aspect of the present invention, a gas stove is provided. The gas stove includes:

[0006] The first burner includes a first mounting base and a first burner head, wherein the first burner head is rotatably connected to the first mounting base;

[0007] The second burner includes a second mounting base and a second burner head. The second burner head is fixedly connected to the second mounting base. A channel is provided on the side of the second burner head, and the channel communicates with the center of the second burner head. The first burner head can pass through the channel, and at least a portion of it is located at the center of the second burner head.

[0008] According to one embodiment of the present invention, the second burner head includes, from bottom to top, an ejector section, a first mixing section and a second mixing section, the first mixing section being "C" shaped, the second mixing section being annular and coaxially overlapping and connected with the first mixing section, and the bottom of the first mixing section being connected to the ejector section.

[0009] According to one embodiment of the present invention, the ejector portion includes an ejector cavity, the top of the ejector cavity is connected to a top plate, the bottom of the first gas mixing portion is fixedly connected to the top plate, the top plate is provided with a through hole, and the ejector cavity is connected to the first gas mixing portion through the through hole;

[0010] The top plate, the two ends of the first mixing section, and the bottom of the second mixing section together define the channel.

[0011] According to one embodiment of the present invention, the first burner head has two working positions, one of which is a first working position in which the first burner head and the second burner head do not overlap, and the other of which is a second working position in which the first burner head and the second burner head overlap.

[0012] According to one embodiment of the present invention, the first mounting base is provided with gas passages corresponding to each of the working positions, each gas passage is independent of each other, and each gas passage supplies gas to the first burner when it is in the corresponding position.

[0013] According to one embodiment of the present invention, an ejector tube is connected between the first mounting base and the first burner head, and the first burner further includes a rotating component for driving the first burner head to rotate, the rotating component comprising:

[0014] A rotating assembly is connected between the first mounting base and the ejector tube;

[0015] The drive component is connected at one end to the first mounting base and at the other end to the rotating component;

[0016] The drive assembly drives the ejector tube and the first burner head to perform circular motion through the rotating assembly, so that the first burner head can switch between multiple working positions.

[0017] According to one embodiment of the present invention, a third burner is further included, the third burner comprising a third mounting base and a third burner head, the third mounting base and the third burner head being fixedly connected.

[0018] According to one embodiment of the present invention, the centers of the cross-sections of the first burner head, the second burner head, and the third burner head are collinear.

[0019] According to one embodiment of the present invention, the center line connecting the cross-sections of the first burner head, the second burner head, and the third burner head forms a triangle.

[0020] According to one embodiment of the present invention, it further includes:

[0021] The cooker housing, the first mounting base, the second mounting base and the third mounting base are all fixedly connected to the cooker housing;

[0022] A panel is provided on the top of the stove housing, and the panel has mounting holes for installing the first burner, the second burner and the third burner;

[0023] The energy-concentrating plate includes an energy-concentrating plate housing located above the panel, and the energy-concentrating plate housing has a first circular hole corresponding to the first burner head, the third burner head, and each of the second burners head.

[0024] According to one embodiment of the present invention, the energy-concentrating disk further includes:

[0025] The first support leg is connected at the bottom to the top of the panel, and at the top of the energy-concentrating disk housing and located at the top of the first circular hole;

[0026] The second support leg is connected to the top of the two adjacent first circular holes.

[0027] One embodiment of the present invention has the following advantages or beneficial effects:

[0028] The present invention allows the first burner to rotate horizontally, enabling the first burner head and the second burner head to be stacked, facilitating diverse choices for users according to their cooking needs and improving the user experience.

[0029] By opening multiple independent gas passages in the first mounting base, the present invention can effectively achieve ignition of the first burner in different working positions, ensuring safety and reliability. Attached Figure Description

[0030] The above and other features and advantages of the present invention will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0031] Figure 1 This is a first schematic diagram of a gas stove according to an exemplary embodiment.

[0032] Figure 2 This is a second schematic diagram of a gas stove according to an exemplary embodiment.

[0033] Figure 3 This is a schematic diagram showing the connection of a first burner, a second burner, a third burner, and a cooktop housing according to an exemplary embodiment.

[0034] Figure 4 This is a schematic diagram of a second burner according to an exemplary embodiment.

[0035] Figure 5 This is a cross-sectional view of a second burner according to an exemplary embodiment.

[0036] Figure 6 This is a cross-sectional view of a rotary burner according to an exemplary embodiment.

[0037] Figure 7 This is an isometric view of a rotary burner according to an exemplary embodiment.

[0038] Figure 8 This is a schematic diagram of an energy-concentrating disk according to an exemplary embodiment.

[0039] The reference numerals in the attached figures are explained as follows:

[0040] 1. First burner; 11. First mounting base; 110. Gas passage; 111. Mounting bracket; 112. Mounting block; 113. Nozzle; 12. First furnace head; 13. Injector tube; 14. Rotating component; 141. Rotating assembly; 1411. Cylinder; 14111. Notch; 1412. Drive arm; 142. Drive assembly;

[0041] 2. Second burner; 21. Second mounting base; 22. Second furnace head; 220. Passage; 221. Injector section; 2210. Injector cavity; 2211. Top plate; 22111. Through hole; 222. First mixing section; 223. Second mixing section;

[0042] 3. Third burner; 31. Third mounting base; 32. Third furnace head;

[0043] 4. Stove casing;

[0044] 5. Panel;

[0045] 6. Energy-concentrating plate; 61. Energy-concentrating plate housing; 610. First circular hole; 62. First support foot; 63. Second support foot. Detailed Implementation

[0046] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that the invention will be thorough and complete, and the concept of the exemplary embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted.

[0047] The terms “a,” “one,” “the,” and “the” are used to indicate the existence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended meaning of inclusion and that other elements / components / etc. may exist in addition to the listed elements / components / etc.

[0048] An embodiment of the present invention provides a gas stove comprising a first burner 1 and a second burner 2. The first burner 1 includes a first mounting base 11 and a first burner head 12. The first burner head 12 is rotatably connected to the first mounting base 11 and rotates around the center of the first mounting base 11. When cleaning the gas stove, the first burner head 12 can be rotated to the side away from the panel for easy cleaning by the user. The second burner 2 includes a second mounting base 21 and a second burner head 22. The second burner head 22 is fixedly connected to the second mounting base 21. A channel 220 is provided on the side of the second burner head 22 for the passage of the first burner head 12. The channel 220 communicates with the center position of the second burner head 22. The first burner head 12 can pass through the channel 220, and at least a portion of it is positioned at the center position of the second burner head 22. The first burner head 12 can be freely combined with each second burner head 22 to form different heating sources. Preferably, the centers of the first burner head 12 and the second burner head 22 coincide, resulting in uniform gas output from the stacked first burner 1 and second burner 2.

[0049] There is one first burner 1 and one second burner 2. Figure 1-3 The diagram illustrates the relationship between the two working positions of the first burner 12 and the second burner 22, and is not intended to limit this application. In the first working position, the first burner 12 does not overlap with the second burner 22, meaning that the first burner 12 and the second burner 22 serve as two different heating sources. When the user requires higher heat, the first burner 12 enters the center position of the second burner 22 through the channel 220, achieving the superposition of the heat from the first burner 12 and the second burner 22 to form a new heating source with higher heat, resulting in faster heating and meeting the demand for high heat in cooking.

[0050] Figure 4 The second burner head 22 shown includes a furnace body 221 and a flame cover. The furnace body 221 includes an ejector section 221, a first gas mixing section 222 and a second gas mixing section 223 from bottom to top. The first gas mixing section 222 is C-shaped. The second gas mixing section 223 is annular and coaxially overlaps and connects with the first gas mixing section 222. The bottom of the first gas mixing section 222 is connected to the ejector section 221. The flame cover is placed on the top of the second gas mixing section 223.

[0051] According to one embodiment of the present invention, the ejector section 221 includes an ejector cavity 2210, the top of the ejector cavity 2210 is connected to a top plate 2211, the bottom of the first gas mixing section 222 is fixedly connected to the top plate 2211, the top plate 2211 has a through hole 22110, and the ejector cavity 2210 is connected to the first gas mixing section 222 through the through hole 22110; wherein, the top plate 2211, the two ends of the first gas mixing section 222 and the bottom of the second gas mixing section 223 together define a channel 220, through which the first burner head 12 can enter and exit the furnace body 221; in addition, the projection of the channel 220 on the axial section of the first burner head 12 can be rectangular or trapezoidal, preferably trapezoidal, and the top of the trapezoid is the short side, and the hypotenuse of the trapezoid can facilitate the rapid entry of the gas located in the first gas mixing section 222 into the second gas mixing section 223, ensuring a uniform gas output rate of the burner cap.

[0052] like Figure 1-3 The first burner head 12 shown has two working positions, namely a first working position and a second working position. When the first burner head 12 is in the first working position, the first burner head 12 and the second burner head 22 do not overlap (e.g., Figure 1 (As shown in the diagram). In the first working position, the first burner 12 and the second burner 22 each function as an independent heating source, with the first burner 12 operating at a low flame. In the second working position, the first burner 12 passes through the channel 220, and the center of the first burner 12 coincides with the center of the second burner 22. This overlap of the first burner 12 and the second burner 22 forms a new heat source whose heat output is equal to the sum of the two corresponding heat outputs, effectively increasing the heating rate and meeting the high heat requirements of cooking. Simultaneously, it ensures that the overlapping of the first burner 12 and the second burner 22 creates a stable and uniform flame, improving the user experience.

[0053] like Figure 3 , 5 As shown in Figure 6, the first mounting base 11 includes a mounting bracket 111, a mounting block 112, and a nozzle 113 connected to each gas passage 110. In order to supply gas to the first burner 12 in different working positions, this application optimizes the gas passage structure by opening a gas passage 110 corresponding to each working position in the mounting block 112. Each gas passage 110 is independent of each other, and each gas passage 110 supplies gas to the first burner 12 when it is in the corresponding position.

[0054] In a preferred embodiment of the present invention, the gas stove further includes a three-way valve, a solenoid valve, a position sensor for sensing the position of the first burner 12, and a controller. The main gas pipe can supply gas independently to each gas path 110 via the three-way valve. Preferably, a solenoid valve is installed between the three-way valve and each gas path 110. By controlling the opening and closing of the solenoid valves on different gas paths 110, the gas supply and closing of different gas paths 110 can be controlled. The controller controls the opening or closing of the corresponding control valve based on the signal from the position sensor. For example, when the position sensor detects that the first burner 12 has moved to the first working position, ... Figure 1 As shown, the controller opens the solenoid valve on the left, connecting the air passage 110 corresponding to the first working position with the air outlet on the left side of the multi-way valve, and then through the nozzle 113 on the corresponding air passage 110. Figure 1 and 4 The nozzle 113 on the left side can supply gas to the first burner head 12 located in the first working position. When the position sensor detects that the first burner head 12 has moved to the second working position... Figure 2-3 As shown, the controller opens the solenoid valve on the right, causing the valve located at... Figure 4 The gas passage 110 on the right side is connected to the gas outlet on the right side of the multi-way valve, and then gas is supplied to the first burner head 12 through the nozzle 113 on the right gas passage 110. This design can effectively realize the ignition of the burner in different working positions, which is safe and reliable. Moreover, through the position sensor, controller and each solenoid valve, it can be determined whether the first burner head 12 is in the first working position or the second working position, avoiding the problem of gas leakage. Because if the rotating mechanism 7 is misoperated or fails, the first burner head 12 will not be able to rotate to the specified working position. If either the first control valve and / or the second control valve is opened at this time, the gas cannot enter the injector tube 13 and the first burner head 12, and gas leakage will occur. Therefore, the gas leakage problem can be effectively avoided.

[0055] like Figure 5-6 An ejector tube 13 is connected between the first mounting base 11 and the first burner head 12. The first burner 1 also includes a rotating component 14 for driving the first burner head 12 to rotate. The rotating component 14 includes a rotating assembly 141 and a driving assembly 142. The rotating assembly 141 is connected to the first mounting base 11 and the ejector tube 13, and the driving assembly 142 is connected to the first mounting base 11 and the rotating assembly 141. The driving assembly 142 drives the ejector tube 13 and the first burner head 12 to perform circular motion through the rotating assembly 141, so that the first burner head 12 can switch between multiple working positions.

[0056] The rotating assembly 141 may include a cylinder 1411 and a drive arm 1412. The cylinder 1411 is rotatably connected to the support frame 31. The cylinder 1411 has a notch 14111 corresponding to the ejector tube 13. The drive arm 1412 connects the cylinder 1411 and the ejector tube 13, so that the ejector tube 13 and the notch 14111 correspond. The drive end of the drive assembly 142 is connected to the cylinder 1411 and is used to drive the cylinder 1411 to rotate. It should be noted that the drive assembly 142 can be a rotary motor or a rotary cylinder. The drive assembly 142 can directly drive the cylinder 1411 to rotate or can use other transmission components to drive the cylinder 1411 to rotate. For example, the drive assembly 142 and the cylinder 1411 are driven by two gears. The cylinder 1411 is sleeved on the outer periphery of the support frame 31 and can rotate around the support frame 31.

[0057] Preferably, the rotating mechanism 14 further includes a limiting component connected to the cylinder 1411 to limit the rotation range of the cylinder 1411. Taking the ability of the cylinder 1411 to switch between two working positions as an example, a first protrusion is provided on the inner circumference of the cylinder 1411, and corresponding second and third protrusions are provided on the outer circumference of the mounting block 32. When the first burner head 12 moves to the first working position, the first and second protrusions inside the cylinder 1411 abut against each other; when the first burner head 12 moves to the second working position, the second and third protrusions inside the cylinder 1411 abut against each other, thereby enabling the switching of the first burner head 12 between the two working positions via the cylinder 1411.

[0058] In a preferred embodiment of the invention, a third burner 3 is further included. The third burner 3 includes a third mounting base 31 and a third burner head 32, which are fixedly connected. The third burner 3 is a conventional burner used in the prior art for outputting stable heat. Figure 1-3 As shown, the gas stove can be equipped with three burners, from left to right: the third burner 3, the first burner 1, and the second burner 2. The first burner 1 can be stacked with the second burner 2 to form a new heat source. By combining the third burner 3, the first burner 1, and the second burner 2, the heat range is increased to meet different heating needs and broaden the applicability of the gas stove.

[0059] In a preferred embodiment of the present invention, the centers of the cross-sections of the first burner head 12, the second burner head 22, and the third burner head 32 are collinear. When the first burner head 12 is in the first working position, the projection centers of the first burner head 12, the second burner head 22, and the third burner head 32 projected onto the plane of the panel 5 are collinear, as shown in the figure. Figure 1-3The first burner 1 is located between the third burner 3 and the second burner 2. Alternatively, the second burner 2 can be positioned between the first burner 1 and the third burner 3, as long as the centers of the first burner head 12, the second burner head 22, and the third burner head 32 are collinear. This design facilitates the processing of the panel 5 and meets the usage needs of most apartment layouts, while also allowing for the sharing of a single pot support, resulting in an aesthetically pleasing overall appearance. When the first burner 1 is located between the third burner 3 and the second burner 2, the first mounting base 11 is installed on the side closer to the second burner 2 to prevent the first burner head 12 from colliding with the third burner 3 during rotation.

[0060] In a preferred embodiment of the present invention, the center lines connecting the cross-sections of the first burner 12, the second burner 22, and the third burner 32 form a triangle. For example, when cleaning the gas stove, the first burner 12 can be rotated to a side away from the second burner 22 and the third burner 32 for easier cleaning. Alternatively, in certain special apartment layouts or according to customer needs, the first working position of the first burner 12 can be set away from the longitudinal section of the second burner 22 and the third burner 32. This design occupies a small area and makes full use of space.

[0061] like Figure 1-3 The gas stove shown in Figure 7 also includes a stove housing 4, a panel 5, and an energy-concentrating plate 6. The panel 5 covers the top of the stove housing 4. The energy-concentrating plate 6 includes an energy-concentrating plate housing 61 located above the panel 5. The panel 5 has mounting holes for installing the first burner 1, the second burner 2, and the third burner 3. The energy-concentrating plate housing 61 has first round holes 610 corresponding to the first burner head 12, the third burner head 32, and each of the second burner heads 22. The bottoms of the first mounting base 11, the second mounting base 21, and the third mounting base 31 are all fixedly connected to the stove housing 4. The tops of the first burner 1, the second burner 2, and the third burner 3 pass through the mounting holes and the first round holes 610 in sequence. Figure 1-2 As shown in Figure 7, the first burner 1, the second burner 2, and the third burner 3 share a single energy-concentrating plate 6. Except for a portion of the first mounting base 11 not covered by the energy-concentrating plate 6, most areas of the first burner 1, the second burner 2, and the third burner 3 are covered by the pot support, resulting in a more aesthetically pleasing overall appearance of the stove. During manufacturing, only three first circular holes 610 need to be drilled in one energy-concentrating plate 6 to meet the needs of the first burner 1, the second burner 2, and the third burner 3, simplifying the process and achieving good heat concentration.

[0062] from Figure 1-2Figures 7 and 8 also show that the energy-concentrating plate 6 includes a first support leg 62 and a second support leg 63. The second support leg 63 is connected to the top of two adjacent first circular holes 610, the bottom of the first support leg 62 is connected to the top of the panel 5, and the top of the first support leg 62 passes through the energy-concentrating plate housing 61 and is located at the top of the first circular hole 610. Multiple first support legs 62 allow the energy-concentrating plate housing 61 to be positioned above the panel 5 and can cooperate with the first burner 12, the third burner 32, and each second burner 22 to improve the thermal efficiency of the first burner 1, the second burner 2, and the third burner 3. Both the first support leg 62 and the second support leg 63 can serve as support points for the cookware. Multiple support points are provided on the outer periphery of each first circular hole 610 to ensure even force distribution on the cookware.

[0063] In this embodiment of the invention, the term "multiple" refers to two or more, unless otherwise explicitly defined. The terms "install," "connect," and "fix" should be interpreted broadly. For example, "connect" can mean a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this embodiment of the invention based on the specific circumstances.

[0064] In the description of the embodiments of the present invention, it should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or unit referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of the present invention.

[0065] In the description of this specification, the terms "an embodiment," "a preferred embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0066] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. For those skilled in the art, various modifications and variations can be made to the embodiments of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the embodiments of the present invention should be included within the protection scope of the embodiments of the present invention.

Claims

1. A gas stove, characterized in that, include: The first burner (1) includes a first mounting base (11) and a first burner head (12), the first burner head (12) being rotatably connected to the first mounting base (11). The second burner (2) includes a second mounting base (21) and a second burner head (22). The second burner head (22) is fixedly connected to the second mounting base (21). A channel (220) is provided on the side of the second burner head (22). The channel (220) is connected to the center of the second burner head (22). The first burner head (12) can pass through the channel (220), and at least a part of it is located at the center of the second burner head (22). The second burner head (22) includes, from bottom to top, an ejector section (221), a first mixing section (222), and a second mixing section (223). The first mixing section (222) is C-shaped, and the second mixing section (223) is annular and coaxially overlapped and connected with the first mixing section (222). The bottom of the first mixing section (222) is connected to the ejector section (221). The ejector section (221) includes an ejector cavity (2210), the top of which is connected to a top plate (2211), the bottom of which is fixedly connected to the top plate (2211), the top plate (2211) has a through hole (22110), and the ejector cavity (2210) is connected to the first gas mixing section (222) through the through hole (22110). The top plate (2211), the two ends of the first mixing section (222), and the bottom of the second mixing section (223) together define the channel (220); the projection of the channel (220) onto the axial section of the first burner head (12) is trapezoidal, and the top of the trapezoid is the short side, and the hypotenuse of the trapezoid facilitates the rapid entry of the gas located in the first mixing section (222) into the second mixing section (223). The first burner head (12) has two working positions, one of which is a first working position in which the first burner head (12) and the second burner head (22) do not overlap, and the other working position is a second working position in which the first burner head (12) and the second burner head (22) overlap; In the first working position, the first burner (12) and the second burner (22) are each independently used as a heating source, wherein the first burner (12) is in a low flame; when the first burner (12) is in the second working position, the first burner (12) passes through the channel (220), and the center of the first burner (12) coincides with the center of the second burner (22); The first mounting base (11) has an air passage (110) corresponding to each working position. Each air passage (110) is independent of each other and each air passage (110) supplies gas to the first burner (12) when it is in the corresponding position. An ejector tube (13) is connected between the first mounting base (11) and the first burner head (12). The first burner (1) also includes a rotating component (14) for driving the first burner head (12) to rotate. The rotating component (14) includes: A rotating assembly (141) is connected between the first mounting base (11) and the ejector tube (13); The drive assembly (142) is connected at one end to the first mounting base (11) and at the other end to the rotating assembly (141). The drive assembly (142) drives the ejector tube (13) and the first burner head (12) to perform circular motion through the rotating assembly (141), so that the first burner head (12) can switch between multiple working positions.

2. The gas stove according to claim 1, characterized in that, It also includes a third burner (3), which includes a third mounting base (31) and a third burner head (32), which are fixedly connected.

3. The gas stove according to claim 2, characterized in that, The centers of the cross-sections of the first burner head (12), the second burner head (22), and the third burner head (32) are collinear.

4. The gas stove according to claim 2, characterized in that, The center line connecting the cross-sections of the first burner head (12), the second burner head (22), and the third burner head (32) forms a triangle.

5. The gas stove according to claim 3, characterized in that, Also includes: The stove housing (4) is fixedly connected to the first mounting base (11), the second mounting base (21) and the third mounting base (31); A panel (5) is provided on the top of the stove housing (4), and the panel (5) has mounting holes for installing the first burner (1), the second burner (2) and the third burner (3); The energy-concentrating plate (6) includes an energy-concentrating plate housing (61) located above the panel (5), and the energy-concentrating plate housing (61) has a first circular hole (610) corresponding to the first burner (12), the third burner (32) and the second burner (22).

6. The gas stove according to claim 5, characterized in that, The energy-concentrating disk (6) also includes: The first support foot (62) is connected at the bottom to the top of the panel (5) and at the top through the energy-concentrating disk housing (61) and located at the top of the first circular hole (610); The second support foot (63) is connected to the top of the two adjacent first circular holes (610).

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