Eccentric wheel mechanism for demonstration

Abstract

The invention relates to the technical field of mechanical structure principle demonstration, and discloses an eccentric wheel mechanism for demonstration, which comprises a rack, two diagonal positions on the rack are respectively provided with a first through hole and a second through hole, and one side of the rack is provided with a crank, a connecting rod and a first rocker / slider which are hinged in sequence; an eccentric wheel composed of a wheel frame and a disc rotatably arranged in the wheel frame is arranged on the other side of the machine frame, and the wheel frame is hinged to the second rocker / sliding block. The eccentric wheel mechanism for demonstration is simple in structure, low in cost, suitable for being used as a teaching aid and easy and convenient to assemble, and the motion relation between an eccentric wheel sliding block mechanism and a crank sliding block mechanism or the motion relation between an eccentric wheel four-bar mechanism and a hinge four-bar mechanism can be visually seen and easily understood; one set of teaching aid can be assembled to demonstrate the motion relation of two mechanical mechanisms, the operation is simple and convenient, the teaching aid is suitable for students to operate as an experimental device, and the teaching effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical structure principle demonstration, and in particular to an eccentric wheel mechanism for demonstration. Background Art

[0002] When students majoring in mechanics are studying the course of mechanical principles, when teachers explain the structure of the eccentric mechanism and its motion diagram, they usually give theoretical explanations, which are difficult for students to understand and the teaching effect is not ideal. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the above-mentioned defects and provide an eccentric wheel mechanism for demonstration, which can be assembled to demonstrate the motion relationship of the mechanical mechanism, and can intuitively see and easily understand the motion relationship between the eccentric wheel slider mechanism and the crank slider mechanism, or the motion relationship between the eccentric wheel four-bar mechanism and the hinge four-bar mechanism.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: An eccentric wheel mechanism for demonstration includes a frame, on which a first through hole and a second through hole are respectively arranged at two diagonal positions, wherein the first through hole is located at one corner position above the frame, and the second through hole is located at another corner position below the frame; A crank, a connecting rod and a first rocker arm are hinged in sequence on one side of the frame, the second end of the crank is hinged to the first end of the connecting rod; the second end of the connecting rod is hinged to the first end of the first rocker arm; the second end of the first rocker arm is hinged to the second through hole; An eccentric wheel consisting of a wheel frame and a disc rotatably arranged in the wheel frame and a second rocker with one end hinged to the wheel frame are arranged on the other side of the frame; a rotation center hole is arranged at a non-center position of the disc; The first end of the crank is coaxially hinged with the rotating center hole of the disc at the first through hole on the frame; the second end of the first rocker and the other end of the second rocker are coaxially hinged at the second through hole on the frame.

[0005] Furthermore, a crank is mounted on the disc to drive the disc to rotate around the rotating center hole; the crank is mounted at the rotating center hole or mounted on the disc through an independent mounting hole.

[0006] Furthermore, the distance between the hinge points at both ends of the crank is equal to the distance between the center of the rotating center hole and the center of the disk.

[0007] Furthermore, the first rocker arm and the second rocker arm have the same length and are universally interchangeable.

[0008] Furthermore, each hinge point is provided with a hinge hole having the same diameter as the rotation center hole, the first through hole and the second through hole, and each hinge hole is provided with a pair of universal male and female pins that can be interlocked; wherein the pin rod sleeve of the female pin can cooperate with the pin rod shaft of the male pin; Washers with different thicknesses are sleeved on each male pin; the inner hole diameters of each washer are the same.

[0009] Furthermore, a storage box with a cover is arranged on the bottom rod of the frame, which is used to store a plurality of male pins, female pins and washers to prevent the male pins, female pins and washers from being lost.

[0010] The present invention also provides another technical solution: An eccentric wheel mechanism for demonstration comprises a frame, a first through hole is arranged at a corner position above the frame; a linear guide groove is arranged horizontally above the frame to accommodate a sliding block to slide therein; A hinged crank, connecting rod and slider are arranged on one side of the frame; the second end of the crank is hinged to the first end of the connecting rod; the second end of the connecting rod is hinged to the slider; An eccentric wheel consisting of a wheel frame and a disc rotatably arranged in the wheel frame is arranged on the other side of the frame, and the wheel frame is hinged on the slider; a rotation center hole is arranged at a non-center position of the disc; The first end of the crank is coaxially hinged with the rotating center hole of the disc at the first through hole on the frame.

[0011] Furthermore, a crank is mounted on the disc to drive the disc to rotate around the rotating center hole; the crank is mounted at the rotating center hole or mounted on the disc through an independent mounting hole.

[0012] Furthermore, the distance between the hinge points at both ends of the crank is equal to the distance between the center of the rotating center hole and the center of the disk.

[0013] Furthermore, each hinge point is provided with a hinge hole having the same diameter as the rotation center hole and the first through hole, and each hinge hole is provided with a pair of universal male and female pins that can be interlocked; wherein the pin rod sleeve of the female pin can cooperate with the pin rod shaft of the male pin; Washers with different thicknesses are sleeved on each male pin; the inner hole diameters of each washer are the same.

[0014] Beneficial effects of the present invention: The present invention provides an eccentric wheel mechanism for demonstration, which has a simple structure and low cost, is suitable for use as a teaching aid, is easy to assemble, and can intuitively see and easily understand the motion relationship between an eccentric wheel slider mechanism and a crank slider mechanism, or the motion relationship between an eccentric wheel four-bar mechanism and a hinge four-bar mechanism; a set of teaching aids can be assembled to demonstrate the motion relationship between two mechanical mechanisms, is easy to operate, is convenient for learning and understanding the mechanism motion of the eccentric wheel mechanism and its motion diagram, is suitable for use as an experimental device for students to operate by themselves, and improves teaching effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are used to provide a preferred understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 Schematic diagram of a hinged four-bar mechanism of Embodiment 1; Figure 2 This is a schematic diagram of the eccentric wheel four-bar mechanism of the first embodiment (the storage box is not shown); Figure 3 A schematic diagram of a slider crank mechanism of Embodiment 2 (the storage box is not shown); Figure 4 This is a schematic diagram of the eccentric wheel slider mechanism of the second embodiment (the storage box is not shown); The accompanying drawings are marked as: frame 1, first through hole 11, second through hole 12, linear guide groove 13, hinge four-bar mechanism 20, crank 21, connecting rod 22, first rocker 23, eccentric wheel four-bar mechanism 30, wheel frame 31, disk 32, rotating center hole 321, center of circle 322, second rocker 33, rocker 34, crank slider mechanism 40, slider 41, third through hole 43, eccentric wheel slider mechanism 50, first hinge point 61, second hinge point 62, third hinge point 63, fourth hinge point 64, storage box 7, female pin 8. DETAILED DESCRIPTION

[0016] The specific implementation of the present invention will be described below with reference to the accompanying drawings. Embodiment 1

[0017] like Figure 1 and Figure 2 As shown, this embodiment discloses an eccentric wheel mechanism for demonstration, which is used to help students who study mechanical principles to better understand the mechanism motion diagram of the eccentric wheel mechanism. Figure 1 The same hinged four-bar mechanism is connected in parallel.

[0018] The eccentric wheel mechanism used for demonstration includes a frame 1, one side of which can be assembled into a hinged four-bar mechanism 20, and the other side can be assembled into an eccentric wheel four-bar mechanism 30. The hinged four-bar mechanism 20 includes a crank 21, a connecting rod 22 and a first rocker 23 that are hinged in sequence. The eccentric wheel four-bar mechanism 30 includes a second rocker 33 hinged on the eccentric wheel; the eccentric wheel is composed of a wheel frame 31 and a disk 32 rotatably arranged in the wheel frame 31. The first end of the second rocker 33 is hinged at a third hinge point 63 on the wheel frame 31. A rotation center hole 321 is provided on the disk 32 at a position close to the edge, and a rocker 34 is also installed on the disk 32. The rocker 34 can be installed in the rotation center hole 321 or installed on the disk through an independent mounting hole.

[0019] The frame 1 is provided with a first through hole 11 and a second through hole 12 at two diagonal positions, wherein the first through hole 11 is located at one corner position above the frame, and the second through hole 12 is located at another corner position below the frame.

[0020] The first end of the crank 21 is coaxially hinged with the rotation center hole 321 of the disk 32 at the first through hole 11 on the frame 1; the second end of the crank 21 and the first end of the connecting rod 22 are hinged at the first hinge point 61. The first hinge point 61 is always coaxial with the center 322 of the disk 32. The distance between the hinges at both ends of the crank is equal to the eccentricity of the eccentric wheel, which is the distance between the center of the rotation center hole 321 and the center 322 of the disk 32.

[0021] The second end of the connecting rod 22 and the first end of the first rocker 23 are hinged at the second hinge point 62. The first end of the second rocker 33 is hinged at the third hinge point 63 on the wheel frame 31. The hinge positions of the second hinge point 62 and the third hinge point 63 are coaxial. The first rocker 23 and the second rocker 33 have the same length, and the hinge positions of the two rockers and the frame are coaxial, that is, the second ends of the first rocker 23 and the second rocker 33 are both hinged at the second through hole 12 on the frame 1.

[0022] By driving the crank and the eccentric wheel to rotate synchronously and at the same speed through a rocker 34, it can be seen that the rocker movement in the hinged four-bar mechanism is exactly the same as the rocker movement in the eccentric wheel four-bar mechanism, and the first hinge point 61 where the second end of the crank 21 is hinged to the first end of the connecting rod 22 is always coaxial with the center 322 of the eccentric wheel disk 32, that is, the movement of the eccentric wheel four-bar mechanism and the hinged four-bar mechanism is equivalent, and it can be clearly and easily understood that the mechanism movement diagram of the eccentric wheel four-bar mechanism is the hinged four-bar mechanism, and the length of the crank is equal to the eccentric distance of the eccentric wheel. In the teaching process, through demonstration or letting students operate by themselves, students can more intuitively see that the eccentric wheel four-bar mechanism 30 and the hinged four-bar mechanism 20 on both sides of the frame are synchronously moving and equivalent in movement.

[0023] Supports are provided at both ends of the bottom of the frame 1 to increase the stability of the frame.

[0024] A storage box 7 with a cover is arranged on the bottom rod of the frame 1, and the storage box 7 does not affect the movement of each mechanism assembled on the frame 1. The storage box is used to store a plurality of male pins, female pins and washers.

[0025] The crank 21, the connecting rod 22, the first rocker 23, and the second rocker 33 are provided with hinge holes at the first hinge point 61, the second hinge point 62, and the third hinge point 63, which are the same diameter as the rotation center hole 321, the first through hole 11, and the second through hole 12. A pair of universal male and female pins 8 that can be interlocked are installed in each hinge hole, wherein the pin sleeve of the female pin can cooperate with the pin shaft of the male pin. A hinge point is formed at each hinge hole by each pair of male and female pins.

[0026] The frame 1 is also provided with an avoidance arc groove 13 , which is arranged on the movement track of the first hinge point 61 to accommodate the moving first hinge point 61 and avoid movement interference between the frame 1 and the moving first hinge point 61 .

[0027] Since the number of hinged parts at each hinge point is different, the total thickness of the parts assembled at each hinge point is different. In order to make the parts move on parallel planes after assembly and make the movement smooth, when the male and female pins at the hinge point are fitted together, male and female pins with suitable lengths of the pin shaft and pin sleeve can be selected according to the total thickness, and washers of different thicknesses can be set on the male pins as needed. The inner diameters of the washers are the same and have universality.

[0028] In order to ensure that the crank 21 and the disc 32 coaxially hinged at the first through hole 11 always remain synchronized during the rotation process, the female pin is non-rotatably assembled in the rotating center hole 321 of the disc 32, and the outer wall cross-section of the pin sleeve at the other end passing through the first through hole 11 is a circular segment wall. The first end of the crank 21 has a circular segment hole matching the circular segment wall, so that the crank 21 and the disc 32 can rotate synchronously around the first through hole 11. Embodiment 2

[0029] Based on the first embodiment, Figure 3 and Figure 4 As shown, in this embodiment, the first rocker 23 and the second rocker 33 can be replaced with a slider 41. A linear guide groove 13 is horizontally provided above the frame 1. The slider 41 can be stuck in the linear guide groove 13 and slide along the linear guide groove 13. A third through hole 43 is provided in the center of the slider 41.

[0030] After the rocker is replaced with the slider 41, the two mechanisms on both sides of the frame 1 are respectively changed into the crank slider mechanism 40 and the eccentric wheel slider mechanism 50.

[0031] The crank 21 , the connecting rod 22 and the slider 41 which are hinged in sequence form a crank slider mechanism 40 .

[0032] The first end of the crank 21 is coaxially hinged with the rotation center hole 321 of the disk 32 at the first through hole 11 on the frame 1; the second end of the crank 21 is hinged with the first end of the connecting rod 22 at the first hinge point 61. The second end of the connecting rod 22 is hinged at the third through hole 43 on the slider 41. The first hinge point 61 is always coaxial with the center 322 of the disk 32. The distance between the hinges at both ends of the crank is equal to the eccentricity of the eccentric wheel, which is the distance between the center of the rotation center hole 321 and the center 322 of the disk 32.

[0033] The slider 41 and the eccentric wheel form an eccentric wheel slider mechanism 50. The slider 41 is hinged on the eccentric wheel; the eccentric wheel is still composed of a wheel frame 31 and a disc 32 rotatably arranged in the wheel frame 31. The wheel frame 31 is hinged at the third through hole 43 on the slider 41 through a third hinge point 63.

[0034] The second end of the connecting rod 22 , the third hinge point 63 of the wheel frame 31 and the third through hole 43 are all coaxial, forming a fourth hinge point 64 .

[0035] The rest is the same as that of the first embodiment.

[0036] When the crank slider mechanism 40 and the eccentric wheel slider mechanism 50 are driven to rotate at the same time, the hinge center of the second end of the crank 21 will always be coaxial with the center 322 of the disk 32. Similarly, the eccentric wheel in the mechanism motion diagram is a crank with a long eccentric distance, and the connecting rod on the eccentric wheel is a connecting rod in the mechanism motion diagram. The mechanism motion diagram of the eccentric wheel slider mechanism is similar to the crank slider mechanism.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention is described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An eccentric wheel mechanism for demonstration, characterized in that: A frame is provided with a first through hole and a second through hole at two diagonal positions, wherein the first through hole is located at one corner position above the frame, and the second through hole is located at another corner position below the frame; A crank, a connecting rod and a first rocker arm are hinged in sequence on one side of the frame, the second end of the crank is hinged to the first end of the connecting rod; the second end of the connecting rod is hinged to the first end of the first rocker arm; the second end of the first rocker arm is hinged to the second through hole; An eccentric wheel consisting of a wheel frame and a disc rotatably arranged in the wheel frame and a second rocker with one end hinged to the wheel frame are arranged on the other side of the frame; a rotation center hole is arranged at a non-center position of the disc; The first end of the crank is coaxially hinged with the rotating center hole of the disc at the first through hole on the frame; the second end of the first rocker and the other end of the second rocker are coaxially hinged at the second through hole on the frame.

2. The eccentric wheel mechanism for demonstration according to claim 1, characterized in that: A crank for driving the disc to rotate around the rotating center hole is also installed on the disc; the crank is installed at the rotating center hole or installed on the disc through an independent installation hole.

3. The eccentric wheel mechanism for demonstration according to claim 2, characterized in that: The distance between the hinge points at both ends of the crank is equal to the distance between the center of the rotating center hole and the center of the disk.

4. The eccentric wheel mechanism for demonstration according to claim 1, characterized in that: The first rocker arm and the second rocker arm have the same length.

5. The eccentric wheel mechanism for demonstration according to claim 1, characterized in that: A hinge hole having the same diameter as the rotation center hole, the first through hole and the second through hole is provided at each hinge point, and a pair of universal male and female pins that can be interlocked are installed in each hinge hole; Washers with different thicknesses are sleeved on each male pin; the inner hole diameters of each washer are the same.

6. The eccentric wheel mechanism for demonstration according to claim 1, characterized in that: A storage box with a cover is arranged on the bottom rod of the frame.

7. An eccentric wheel mechanism for demonstration, characterized in that: It comprises a frame, a first through hole is arranged at a corner position above the frame; a linear guide groove is arranged horizontally above the frame to accommodate a slide block to slide therein; A hinged crank, connecting rod and slider are arranged on one side of the frame; the second end of the crank is hinged to the first end of the connecting rod; the second end of the connecting rod is hinged to the slider; An eccentric wheel consisting of a wheel frame and a disc rotatably arranged in the wheel frame is arranged on the other side of the frame, and the wheel frame is hinged on the slider; a rotation center hole is arranged at a non-center position of the disc; The first end of the crank is coaxially hinged with the rotating center hole of the disc at the first through hole on the frame.

8. The eccentric wheel mechanism for demonstration according to claim 7, characterized in that: A crank for driving the disc to rotate around the rotating center hole is also installed on the disc; the crank is installed at the rotating center hole or installed on the disc through an independent installation hole.

9. The eccentric wheel mechanism for demonstration according to claim 7, characterized in that: The distance between the hinge points at both ends of the crank is equal to the distance between the center of the rotating center hole and the center of the disk.

10. The eccentric wheel mechanism for demonstration according to claim 7, characterized in that: A hinge hole having the same diameter as the rotation center hole and the first through hole is provided at each hinge point, and a pair of universal male and female pins that can be interlocked are installed in each hinge hole; Washers with different thicknesses are sleeved on each male pin; the inner hole diameters of each washer are the same.

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