Apparatus for approximately generating conical pendulum motion

Abstract

To solve the problem in which it is common to insert a blade-like implement into a container and rotating it in order to stir a fluid, however, this approach has drawbacks such as the labor required for cleaning the implement, and is not generally applied to cooking food, although methods of using conical pendulum motion to stir without inserting anything into the container are known, apparatuses therefor have drawbacks such as large size and are thus also not generally used, and a stirrer available in the form of an IH cooker or the like is in demand.MEANS FOR SOLVING THE PROBLEM: By connecting a table 27 to three or more rotating devices 13 or the like using hinge pins 30 or the like and causing synchronized rotational motion, the table 27 moves analogously to a weight undergoing conical pendulum motion. As a result, a rotation is generated in a fluid placed in a circular container on the table 27. No overhead structure is required to suspend the table 27, and heating from below the table 27 is also possible. The apparatus allows stable rotation with adjustable flow rates, and can be also expected to be applied to aquatic organism cultivation.SELECTED DRAWING: Figure 19

Description

Technical Field

[0001] The present invention relates to an apparatus that can generate a motion approximated to a conical pendulum motion to give a flow velocity to a fluid for the purpose of using it for stirring the fluid or the like, without suspending a weight.

Background Art

[0002] To mechanically stir a fluid, a method of inserting a blade or the like into the fluid in a container and causing a rotational motion or the like is generally used. As another method, a method of applying an external force to a container containing a fluid to cause a conical pendulum motion and giving a flow velocity to the fluid in the container is known, and an apparatus using this method has been proposed in Japanese Patent Laid-Open No. 10-216498.

[0003] The original conical pendulum is a device system in which a weight 1 is suspended from a pendulum fulcrum 3 by a string 2 as shown in FIG. 1. If an initial velocity is given to the weight 1 and there is no frictional resistance in the air or at the pendulum fulcrum 3 portion, it will continue to rotate at a constant speed.

[0004] Incidentally, regarding the period of the constant-speed conical pendulum motion, a relational expression derived from the length 4 of the string and the angle 6 formed between the string 2 and the vertical line 5 is well known. However, in reality, there is frictional resistance, and if the weight 1 is a fluid, resistance due to inertial force is also added, and the conical pendulum motion decays.

[0005] Therefore, in the apparatus of Japanese Patent Laid-Open No. 10-216498, a swirling force is applied from the lower part of the apparatus system by a motor whose vertical direction coincides with the rotation axis. This method has the advantage that the fluid in a sealed container can be stirred without opening the lid of the container.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] It is believed that Japanese Patent Application Laid-Open No. 10-216498 mentioned in the Background Art has the following two drawbacks which hinder its practical use and therefore has not come into general use.

[0008] It is necessary to suspend weight 1 from pendulum support 3 of the conical pendulum motion with a string 2 or rod, which requires a structure at the top to fix pendulum support 3 in space.

[0009] A device is required to apply a rotational force to the bottom of the conical pendulum, which can be a spatial obstacle when heating at the same time. [Means for solving the problem]

[0010] In Figure 2, a large weight 7 suspended from a pendulum fulcrum 3 moves in a conical pendulum with a small angle 6 between the string 2 and the plumb line 5. All of the endpoints of the large weight 7, which is a regular polygon, are equidistant from the center 9 of the weight, so all of the endpoints move on a spherical surface 8 centered on the pendulum fulcrum.

[0011] Orbit 10 of the center of the weight is a circular orbit on a horizontal plane, but any endpoint describes a spherical circular orbit 11 on the sphere as shown in Figure 2. Furthermore, axis 12 of this spherical circular orbit 11 passes through pendulum support 3. The angle between spherical circular orbit 11 and axis 12 of the spherical circular orbit is equal to angle 6 between center of weight 9 and vertical line 5.

[0012] In the device system invented this time, multiple devices arranged around it share the motion on this spherical circular orbit 11 or an orbit similar to it. The entire device system makes weight 1 move in a manner similar to the actual conical pendulum motion, which is characterized by the effect of stirring the fluid. Effect of the Invention

[0013] This can eliminate the suspension device for the pendulum fulcrum 3 and the arrangement of the device for applying the rotational force to the lower part of the weight 1, which are the two drawbacks of the aforementioned Japanese Patent Application Laid-Open No. 10-216498. With a simpler and more compact device system than before, a motion approximating the conical pendulum motion is realized, and effects such as fluid agitation can be obtained.

Brief Description of the Drawings

[0014]

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Mode for Carrying Out the Invention

[0015] What this device system generates is not a conical pendulum motion at a constant speed, but a motion approximated to it. However, there are some concepts in the conical pendulum motion at a constant speed described in FIG. 1 etc. for the sake of explanation that are borrowed. In the conical pendulum motion at a constant speed, there are the pendulum fulcrum 3, the length of the string 4, the angle 6 formed between the string 2 and the vertical line 5, and the period. However, in the invented device system, the relational expression in the conical pendulum motion at a constant speed does not hold between the period and the angle 6 formed between the string 4 and the string.

[0016] In Example 1 and Example 2 described in the next stage, in order for the fluid in the container placed on the table 27 to obtain an efficient rotational motion, the planar shape of the container needs to be circular and its center needs to be aligned with the table center 29. Refer to FIG. 8.

Example

[0017] Example 1 is implemented by three or more rotating devices 13. The following explanation is for the case where there are three rotating devices 13 as an example.

[0018] Detailed views of one rotating device 13 are shown in FIGS. 3 to 5. The metal fitting I16 is for supporting the motor body 14 while adjusting the angle. A plate-shaped arm 17 orthogonal to the motor shaft 15 is attached to the motor shaft 15, and a hinge pipe 18 is obliquely attached to the arm 17 at a position away from the motor shaft 15.

[0019] FIG. 6 shows that the angle formed between the motor shaft 15 and the hinge pipe 18 is the angle 6 formed between the string 2 and the vertical line 5. All the rotating devices 13 to be arranged have the same structure.

[0020] The pedestal 19 is a horizontal plane for fixing the rotating device 13, and the pedestal center 20 is vertically below the pendulum fulcrum 3. One rotating device 13 is arranged at an equal distance from the pedestal center 20 on the pedestal bisector 22 drawn at an angle of 2π / (number of rotating devices) from the pedestal center 20. Also, each rotating device 13 is fixed by adjusting the angle with the fitting 16 so that the extension line 23 of the motor shaft passes through the pendulum fulcrum 3.

[0021] As shown in FIG. 7, the rotation angle origin 24 in the setting of the arm 17 for each rotating device 13 is the position where the tip of each arm 17 points to the pedestal center 20, and the angle measured clockwise is defined as the rotation angle 25.

[0022] The distance between the hinge vibration tips of adjacent rotating devices 13 is defined as the hinge interval 26. At the start of the device system, the rotation angles 25 of adjacent rotating devices 13 are advanced by 2π / (number of rotating devices) as shown in FIG. 7, and all the rotating devices 13 rotate in the same direction and at the same angular velocity. As a result, the hinge interval 26 is kept constant. 2π / (angular velocity) becomes the period of this device system.

[0023] The table 27 for installing the container is planar and is attached so as to cover the upper parts of all the rotating devices 13. The perspective view of FIG. 8 shows the mounting situation by cutting a part of it.

[0024] Holes for the hinge pins 30 are drilled at equal distances from the table center 29 on the table bisectors 28 drawn radially at intervals of an angle of 2π / (number of rotating devices) from the table center 29. The distance between adjacent hinge pins 30 is made equal to the distance of the hinge interval 26 of the rotating device 13. Finally, these holes and the hinge pipes 18 of the rotating device 13 are connected with the hinge pins 30 so that they can rotate smoothly.

Example

[0025] It is also necessary to install three or more sets of the same set of traction devices 31 in the device system of the second embodiment. The figure and the following description describe the case of three sets as an example.

[0026] One set of traction devices 31 is a combination of a partial spherical surface 32 and a linear motor 44. The details of combining one set of traction devices 31 with table legs 37 are shown in FIGS. 9 and 10.

[0027] A frame 41 is attached to the tip of the shaft 40 of the linear motor by a pin joint 42. Due to this pin joint 42, the frame 41 can change its angle only in the horizontal direction without changing the angle in the vertical direction with respect to the shaft 40 of the linear motor. The frame 41 moves along the partial spherical surface 32 and transmits the operation of the shaft 40 of the linear motor to the table leg 37.

[0028] The partial spherical surface 32 has the inner side of the spherical surface portion with a radius equal to the length of the string facing upward. FIG. 11 shows the situation where only the partial spherical surface 32 of one set of traction devices 31 is arranged on the pedestal 19.

[0029] The center of the partial spherical surface 32 is arranged on the pedestal bisector 22 drawn radially at an angle of 2π / (number of traction devices) from the pedestal center 20 of the horizontal pedestal 19. The positions are adjusted so that the ends of the line segments from the centers 33 of all the partial spherical surfaces to the centers of their respective spherical surfaces coincide at the pendulum fulcrum 3 and are fixed to the pedestal 19.

[0030] FIG. 12 shows the arrangement on the pedestal 19 of one set of traction devices 31 with the partial spherical surface 32 plus the linear motor 44 etc. added.

[0031] The projection line of the shaft 40 of the linear motor onto the pedestal 19 is fixed by a fitting 43 so as to coincide with the pedestal bisector 22. The distance from the pedestal center 20 is equidistant for all the linear motors 44, which will be described later.

[0032] The shaft 40 of the linear motor, together with the frame 41 attached to its tip, slides on the upper surface of the partial spherical surface 32 parallel to the tangent plane at the center 33 of the partial spherical surface.

[0033] Table 27 in this example is also planar. As shown in FIG. 13, the same number of table legs 37 as the number of traction devices are attached on the table bisector 28 drawn radially at an angle of 2π / (number of traction devices) from the center 36 of the back surface of the table. A free ball bearing 38 is attached to the tip of the table leg 37, and when the table (back surface) 35 is turned to the front, it can slide while freely rolling within the range on the same number of partial spherical surfaces 32 as shown in FIG. 14.

[0034] If no external force other than gravity is applied to the table 27, the table 27 will be horizontally balanced as shown in FIG. 14. For all the table legs 37, the free ball bearing 38 at their tips contacts at the center 33 of the partial spherical surface, and the axis 39 of the table leg coincides with the straight line towards the pendulum fulcrum 3. The table legs 37 are fixed to the table 27 as shown in FIG. 14 by determining their positions and angles so as to satisfy these conditions.

[0035] When making the water flow clockwise in this device system, the linear motors 44 of the individual traction devices arranged are operated in clockwise order. Also, if this is done counterclockwise, the water flow will be counterclockwise. The following explanation will be given for the clockwise case.

[0036] Regarding the operation of the device system, one set of traction devices 31 out of the multiple ones will be focused on for explanation. When all the linear motors 44 are in the non-operating state, the frame 41 attached to the tip of the axis 40 of the corresponding linear motor is at the position shown in FIG. 15, and the table leg 37 is also at the position of the center 33 of the partial spherical surface.

[0037] Next, when the corresponding linear motor 44 is operated, the frame 41 moves, and the table leg 37 is pulled up as shown in FIG. 16 by being pushed by the frame 41, and the table 27 makes the same movement. Then, when the operation is released, the frame 41 and the table leg 37 return to the non-operating state position shown in FIG. 15.

[0038] The position of the linear motor 44 from the pedestal center 20 described above is determined so that the frame 41 can move in the previous two steps.

[0039] There is the operation of FIG. 16, and after returning to the state of FIG. 15 and after a certain period of time, the traction device adjacent to the right of the corresponding traction device is operated. When the right traction device operates, the table 27 moves in that direction, so the table leg 37 corresponding to the corresponding traction device is also pulled to the right as shown in FIG. 17. However, since the frame 41 can rotate without resistance as shown in the figure, it does not prevent the movement of the table 27. After the operation of the right traction device ends, the frame 41 and the table leg 37 return to the positions in the non-operating state of FIG. 15.

[0040] After another certain period of time, this time the traction device adjacent to the left operates. When the left adjacent traction device operates, the table 27 moves in that direction, so the table leg 37 of the corresponding traction device is also pulled to the left as shown in FIG. 18. However, since the frame 41 can rotate without resistance as shown in the figure, it does not prevent the movement of the table 27. After the operation of the left adjacent traction device ends, the frame 41 and the table leg 37 return to the positions in the non-operating state.

[0041] The operations described from the previous 4 items to the previous item are one cycle of the device system, and an approximate conical pendulum motion is implemented by a series of movements of the table 27.

Industrial Applicability

[0042] This device is considered to be particularly convenient for use at a low speed of around 60 rpm. In the case of low-speed operation, containers such as cooking utensils can be placed on the table 27 and operated without restraint. Since heating can be performed from below, cooking can be performed while avoiding burning without manual stirring.

[0043] During heating, the heat of the container is easily transmitted to the entire fluid, so the heating time can be shortened.

[0044] Also, not only can the fluid be simply stirred, but it is also possible to rotate the fluid in a circular container with adjusted flow velocity. It is considered that this can also be used for breeding aquatic organisms.

Explanation of Signs

[0045] 1 weight 2 Strings 3 Oscillator Fulcrum 4 String Length 5 Vertical Line 6 Clamping Angle 7 Large Weight 8 Sphere Centered on the Oscillator Fulcrum 9 Weight Center 10 Orbit of the Weight Center 11 Spherical Circular Orbit 12 Axis of the Spherical Circular Orbit 13 Rotating Device 14 Motor Body 15 Motor Shaft 16 Metal Fitting I 17 Arm 18 Hinge Pipe 19 Pedestal 20 Pedestal Center 21 Angle of 2π / (Number of Rotating Devices) 22 Pedestal Bisector 23 Extension of the Motor Shaft 24 Rotation Angle Origin 25 Rotation Angle 26 Hinge Spacing 27 Table 28 Table Bisector 29 Table Center 30 Hinge Pin 31 Set of Traction Devices 32 Partial Sphere 33 Center of the Partial Sphere 34 Line Segment from the Center of the Partial Sphere to the Sphere Center 35 Table (Back Side) 36 Center of the Table Back Side 37 Table Leg 38 Ball Bearing 39 Axis of the Table Leg 40 Axis of the Linear Motor 41 Frame 42 Pin Joint 43 Metal Fitting II 44 Linear Motor

Claims

1. The device system for performing an approximate conical pendulum motion by a rotating device as described in Example 1.

2. The device system for performing an approximate conical pendulum motion by a traction device as described in Example 2.

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