CN208781458U - A kind of mathematical education probability demonstration teaching aid - Google Patents
A kind of mathematical education probability demonstration teaching aid Download PDFInfo
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- CN208781458U CN208781458U CN201820372025.8U CN201820372025U CN208781458U CN 208781458 U CN208781458 U CN 208781458U CN 201820372025 U CN201820372025 U CN 201820372025U CN 208781458 U CN208781458 U CN 208781458U
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Abstract
The utility model relates to a kind of mathematical education probability demonstration teaching aids, including round iron box, round iron bucket, several demonstration balls, clamping screw, locking pin, multiple magnet, round iron box includes box body and box cover, box cover includes round table-like lid and cover rim, clamping screw includes bolt head and screw rod, box body is internally provided with multiple partitions, the outer cover of screw rod is equipped with and the one-to-one axle sleeve of partition, the outside of box body is additionally provided with the nut matched with screw rod, locking pin includes square bar, round bar, rectangular baffle, the center of top of lid is provided with the rectangular holding tank matched with baffle, the slot bottom center of holding tank is provided with the second through-hole of circle for square bar and round bar disengaging, the rectangular blind hole matched with square bar is provided at the top of bolt head.The mathematical education is easy to operate with probability demonstration teaching aid, can demonstrate kinds of experiments as a result, helping to improve understanding and Grasping level of the student to probability, promote effect of giving lessons.
Description
Technical field
The utility model relates to a kind of mathematical education probability demonstration teaching aids, belong to teaching aid technical field.
Background technique
Probability is the concept for the rule definition that people occur according to chance event, and in mathematical education, teacher is to make
Student more intuitively learn to probability in terms of knowledge, often through some actual probability lecture experiments, wherein most often doing
It is to throw coin experiment, i.e., by repeatedly throwing coin, counts to obtain the positive and negative probability upwardly of coin and be approximately equal to half.With
Throw coin number it is more, count to obtain the positive and negative probability upwardly of coin also just closer to half.In order to obtain
The positive and negative probability upwardly of coin is equal to experimental result as half, needs to carry out many experiments.
Current throwing coin experiment is more single, can only demonstrate a kind of probability distribution of experimental result, this mode
So that student is not high to the understanding of probability and Grasping level, teacher is also very painstaking during explanation.Therefore, it is badly in need of one
The teaching aid that kind can demonstrate kinds of experiments result carries out cooperation teaching.
Utility model content
The utility model has in view of the deficienciess of the prior art, providing a kind of mathematical education probability demonstration teaching aid
Body technique scheme is as follows:
A kind of mathematical education probability demonstration teaching aid, including round iron box, round iron bucket, several demonstration balls, clamping screw, lock
Shotpin axis, multiple magnet, the round iron box include box body and box cover, and the box cover includes round table-like lid and cover rim, the lid
The side on edge and the top of box body are hinged, and bottom and the round iron bucket of the inside of round iron bucket and box body is arranged in the bottom of the box body
Screw top connection；The clamping screw includes bolt head and screw rod, and the cassette bottom center of the box body is provided with for screw rod tail
The first through hole being pierced by is held, the box body is internally provided with multiple partitions, and the outer cover of the screw rod is equipped with partition one by one
Corresponding axle sleeve, the side of the partition are fixedly connected with the lateral wall of axle sleeve, and the top of axle sleeve, institute is arranged in the bolt head
The outside for stating box body is additionally provided with the nut matched with screw rod, and the nut is connect with screw flight；The locking pin packet
Square bar, round bar, rectangular baffle are included, the tail end of the square bar and the head end of round bar are connected as one, and the round bar and baffle are mutual
Vertically, it is fixedly connected in the middle part of the tail end of the round bar and baffle, the center of top of the lid is provided with to be matched with baffle
Rectangular holding tank, the slot bottom center of the holding tank be provided with for square bar and round bar disengaging the second through-hole of circle, the spiral shell
The rectangular blind hole matched with square bar is provided at the top of bolt head.
As an improvement of the above technical solution, the cassette bottom of the box body is additionally provided with the scale mark for indicating angle, described
Scale indicates the inside that box body is arranged in.
As an improvement of the above technical solution, the bucket bottom of the round iron bucket is provided with the groove for accommodating locking pin, described
Groove is located at the inside of round iron bucket, and the inner wall of the groove is installed with spongy layer.
As an improvement of the above technical solution, handle is installed on the outside of the nut.
As an improvement of the above technical solution, rubber sleeve is additionally provided between the bolt head and axle sleeve.
It as an improvement of the above technical solution, is clearance fit between the axle sleeve and screw rod.
It as an improvement of the above technical solution, is clearance fit between the baffle and holding tank.
As an improvement of the above technical solution, the groove depth of the holding tank is greater than or equal to the thickness of baffle.
It as an improvement of the above technical solution, is clearance fit between the square bar and blind hole.
Mathematical education described in the utility model is easy to operate with probability demonstration teaching aid, can demonstrate kinds of experiments as a result, reality
Can obtain a large amount of statistical result after the completion of testing, and can be vivid be shown, facilitate teacher to probability distribution into
The explanation of row example, helps to improve understanding and Grasping level of the student to probability, so that significant effect promotion of giving lessons.
Detailed description of the invention
Fig. 1 is schematic diagram when mathematical education described in the utility model does not install locking pin with probability demonstration teaching aid；
Fig. 2 is schematic diagram when mathematical education described in the utility model is equipped with locking pin with probability demonstration teaching aid；
Fig. 3 is box body structure schematic diagram (overlooking state) described in the utility model；
Fig. 4 is that the scale in box body cassette bottom described in the utility model indicates schematic diagram；
Fig. 5 is schematic diagram when locking pin described in the utility model is placed on groove；
Fig. 6 is locking pin structural schematic diagram described in the utility model (side view state).
Specific embodiment
In order to make the purpose of the utility model, technical solutions and advantages more clearly understood, below in conjunction with attached drawing and implementation
Example, the present invention will be further described in detail.It should be appreciated that specific embodiment described herein is only used to explain
The utility model is not used to limit the utility model.
As shown in Fig. 1,2,3,6, mathematical education probability demonstration teaching aid, including round iron box, round iron bucket 3, several
Ball 4, clamping screw, locking pin 6, multiple magnet 7 are demonstrated, the round iron box includes box body 1 and box cover, and the box cover includes circle
Mesa-shaped lid 21 and circular cover rim 22, the lateral wall of the lid 21 be it is round table-like, the inner sidewall of the lid 21 is also round
Mesa-shaped, the side of the cover rim 22 and the top of box body 1 are hinged, sharp between the other side of the cover rim 22 and the top of box body 1
It is flexibly connected with hasp, the top opening of the round iron bucket 3, inside and the box body of round iron bucket 3 is arranged in the bottom of the box body 1
1 bottom is connect with the screw top of round iron bucket 3；The clamping screw includes bolt head 51 and screw rod 52, the screw rod 52
Head end is connected as one with bolt head 51, and the cassette bottom center of the box body 1 is provided with the first through hole being pierced by for 52 tail end of screw rod
11, the outside of box body 1 is arranged in the tail end of the screw rod 52, and the inside of box body 1, the box body 1 is arranged in the bolt head 51
Be internally provided with multiple partitions 8, the outer cover of the screw rod 52 is equipped with and the one-to-one axle sleeve 81 of partition 8, that is to say, that
Axle sleeve 81 is provided between the screw rod 52 and partition 8, the axle sleeve 81 is set in the outside of screw rod 52；The side of the partition 8
Side is fixedly connected with the lateral wall of axle sleeve 81, and the top of axle sleeve 81 is arranged in the bolt head 51, and the outside of the box body 1 is also set
It is equipped with the nut 9 matched with screw rod 52, the nut 9 is threadedly coupled with screw rod 52；The locking pin 6 include square bar 61,
The head end of round bar 62, rectangular baffle 63, the tail end and round bar 62 of the square bar 61 is connected as one, the round bar 62 and baffle 63
It is mutually perpendicular to, the central axis of the square bar 61 is conllinear with the central axis of round bar 62, the tail end and baffle 63 of the round bar 62
Middle part be fixedly connected, the center of top of the lid 21 is provided with the rectangular holding tank 211 matched with baffle 63, the appearance
Receive slot 211 slot bottom center be provided with for square bar 61 and round bar 62 disengaging the second through-hole of circle 212, the top of the bolt head 51
Portion is provided with the rectangular blind hole 511 matched with square bar 61.
In the present embodiment, the quantity of the partition 8 is 3, therefore the space of 1 lower part of box body is divided by 3 partitions 8
First subregion slot 1a, the second subregion slot 1b, third subregion slot 1c, as shown in Figure 3；Since axle sleeve 81 is set in the outer of screw rod 52
Portion, is clearance fit between the axle sleeve 81 and screw rod 52, this enables axle sleeve 81 to rotate around screw rod 52, therefore, every
Plate 8 can rotate under the action of axle sleeve 81 around screw rod 52, that is to say, that the spacing between adjacent partition 8 can be any
Adjustment, since length of 3 partitions 8 etc. is all identical, this makes the first subregion slot 1a, the second subregion slot 1b and third subregion
The area of bottom surface where the area of bottom surface, the second subregion slot 1b where volumetric ratio between slot 1c is also equal to the first subregion slot 1a
With the area ratio of bottom surface where third subregion slot 1c；For convenient for the area of bottom surface, second point where the first subregion slot of calculating 1a
Ratio between the area of bottom surface where area slot 1b and the area of the place third subregion slot 1c bottom surface, further, such as Fig. 4 institute
Show, the cassette bottom of the box body 1 is additionally provided with the scale mark 12 for indicating angle, and the scale mark 12 is arranged in box body 1
Portion；Wherein, the scale mark 12 may be designed as graduation mark, and the graduation mark is concentric coplanar setting；It is indicated in scale
With the help of 12, bottom surface where the area of bottom surface, the second subregion slot 1b where capable of intuitively, promptly obtaining the first subregion slot 1a
Area and third subregion slot 1c where bottom surface area between ratio, also just obtained the first subregion slot 1a, the second subregion
Volumetric ratio between slot 1b and third subregion slot 1c.
Volumetric ratio between first subregion slot 1a, the second subregion slot 1b and third subregion slot 1c is set as setting value, such as
Volumetric ratio between first subregion slot 1a, the second subregion slot 1b and third subregion slot 1c is set as 1:3:2.The magnet 7
Quantity is twice of partition 8, and in the present embodiment, the quantity of magnet 7 is 6 pieces.As the first subregion slot 1a, the second subregion slot 1b and
When volumetric ratio between third subregion slot 1c has been set at setting value, if partition 8 at this time is rotated further by, it will make
Setting value generates deviation, will affect final demonstration result.To prevent partition 8 to be rotated further by, it is three pairs that 6 blocks of magnet 7, which are divided, each
The two sides of partition 8 are located to magnet 7, and magnet 7 can be adsorbed on the cassette bottom of box body 1, so that every a pair of magnet 7 can incite somebody to action
Partition 8 also just temporarily avoids partition 8 from rotating again to clamping.Then matching for clamping screw, locking pin 6 and nut 9 is recycled
All axle sleeves 81 are fixed in conjunction, avoid axle sleeve 81 from rotating again around screw rod 52, thus also it is avoided that partition 8 turns again
It is dynamic.It is using the cooperation of clamping screw, locking pin 6 and nut 9 that all securing methods of axle sleeve 81 is as follows: by screw rod 52
Tail end pass through the outside that axle sleeve 81, first through hole 11 make the tail end of screw rod 52 be located at box body 1, at this point, by box cover and box body 1
Fasten, then by locking pin 6 square bar 61 and round bar 62 sequentially pass through the second through-hole 212, then by the head end of square bar 61
Be inserted into rectangular blind hole 511, then can fine rotation locking pin 6 rectangular baffle 63 is fallen into rectangular holding tank 211；
Since partition 8 is clamped by a pair of magnet 7, even if fine rotation locking pin 6, partition 8 will not be made to rotate again.Then will
9 sets of the nut tail ends in screw rod 52 enable nut 9 to be threadedly coupled with screw rod 52 so that bolt head 51 pressed against all axis
Set 81, so that axle sleeve 81 and partition 8 can not be rotated further by.Wherein, during rotating nut 9, if without lock pin
Axis 6, then nut 9, which rotates, easily drives clamping screw rotation, even if partition 8 is clamped by a pair of magnet 7 at this time, also it is easier that partition
8 rotate again, this will lead to setting value and generates deviation, to influence final demonstration result.And in the utility model, due to locking
Square bar 61 and rectangular blind hole 511 in pin shaft 6 cooperate and the cooperation of rectangular baffle 63 and rectangular holding tank 211, so that locking
Bolt can not rotate again, this also avoids partition 8 and rotates again, guarantee the first subregion slot 1a, the second subregion slot 1b and the
The setting value of volumetric ratio does not generate deviation between three subregion slot 1c, and enabling is finally that demonstration result reaches desired design.
After the completion of being fixed all axle sleeves 81 using the cooperation of clamping screw, locking pin 6 and nut 9, by lock pin
Axis 6 is extracted out, then again connect the bottom of box body 1 with the screw top of round iron bucket 3.Finally, opening the lid, all magnet are taken out
7.It wherein, further, is clearance fit between the baffle 63 and holding tank 211.Further, the square bar 61 and blind hole
It is clearance fit between 511.Locking pin 6 may make to be extracted as long as this for be inverted round iron box.It further, is side
Just it installs, the groove depth of the holding tank 211 is greater than or equal to the thickness of baffle 63.
Since the volumetric ratio between the first subregion slot 1a, the second subregion slot 1b and third subregion slot 1c is set as 1:3:2.Institute
Some demonstration balls 4 are the identical ball of diameter.The mathematical education with probability demonstration teaching aid carry out lecture experiment step and
Principle is as follows: being put into all demonstration balls 4 inside to box body 1, then covers box cover and fasten, then embraces box body 1 for round iron
Box is inverted, and the demonstration ball 4 inside box body 1 is all fallen at lid 21 at this time, and the inner cavity of lid 21 at this time is cone cell, demonstrates ball 4
It concentrates at the inner cavity of lid 21, is then just putting round iron box on the table, first can be randomly interspersed by demonstrating ball 4 at this time
Subregion slot 1a, the second subregion slot 1b, third subregion slot 1c；It opens the lid, observe and counts the first subregion slot 1a, the second subregion slot
The quantity of ball 4 is demonstrated in 1b, third subregion slot 1c.Above-mentioned experiment is constantly repeated, is calculated by way of seeking average
Average value, the third subregion slot of 4 quantity of ball are demonstrated in one subregion slot 1a in the average value, the second subregion slot 1b of demonstration 4 quantity of ball
The ratio demonstrated between the average value of 4 quantity of ball in 1c is x, and x is approximately equal to 1:3:2.Wherein, increasing with experiment number, system
It counts obtained x and is also just even equal to 1:3:2 closer to 1:3:2.It can also be by being calculated in single experiment in the first subregion slot 1a
It demonstrates the quantity of ball 4, the quantity that ball 4 is demonstrated in the second subregion slot 1b, demonstrate ratio between the quantity of ball 4 in third subregion slot 1c
Compared between value and setting value 1:3:2, enable student to " deviation " in mathematics, " absolute deviation ", " relative deviation ",
The mathematical concepts such as " standard deviation ", " average deviation " have one to get information about.Also first can be reset according to the actual situation
Volumetric ratio between subregion slot 1a, the second subregion slot 1b and third subregion slot 1c, repeats above-mentioned experiment, to demonstrate a variety of realities
Test as a result, facilitate teacher to probability distribution carry out example explanation, student is intuitively understood, student couple is helped to improve
The understanding of probability and Grasping level.Wherein, it is carried out in lecture experiment, can be locked by holding with probability demonstration teaching aid in mathematical education
Shotpin axis 6 is checked and is counted to the quantity for demonstrating ball 4 in the first subregion slot 1a, the second subregion slot 1b, third subregion slot 1c,
Facilitate inventory operation and to check effect good.Round table-like lid 21 enables it rapidly to concentrate all demonstration balls 4 when being inverted,
What this was conducive to that subsequent demonstration ball 4 can be random fall on the first subregion slot 1a, the second subregion slot 1b, in third subregion slot 1c,
Further increase experimental precision.
Further, the bucket bottom of the round iron bucket 3 is provided with the groove for accommodating locking pin 6, and the groove is located at round iron
The inside of bucket 3, the inner wall of the groove are installed with spongy layer 31.The mathematical education is with probability demonstration teaching aid in teaching demonstration knot
Shu Hou can put locking pin 6 in a groove, then magnet 7 can be all pressed in the top of locking pin 6, since round iron bucket 3 is
Irony, magnet 7 can be adsorbed on the bucket bottom of round iron bucket 3 to which locking pin 6 is fixed in a groove, as shown in Figure 5；And it is recessed
Spongy layer 31 in slot can be filled in the gap between groove inner wall and locking pin 6, can be avoided the shock of locking pin 6
The inner wall of groove.
Further, for convenience of rotating nuts 9, the outside of the nut 9 is installed with handle 91.Further, the spiral shell
The top surface of bolt head 51 is spherical surface, this to demonstrate the easy uniform force when falling on the top surface of bolt head 51 of ball 4, will also to drill
Show that ball 4 can be random striking the top surface of bolt head 51 falls on the first subregion slot 1a or the second subregion slot 1b or third
In subregion slot 1c, experimental error is advantageously reduced.
Further, rubber sleeve 53 is additionally provided between the bolt head 51 and axle sleeve 81.When bolt head 51 is in 9 He of nut
Bolt head 51 is enabled to press rubber sleeve 53 under the cooperation of screw rod 52,53 stress of rubber sleeve is so that all axle sleeve
81 are pressed fixation, and axle sleeve 81 is fixed stronger, so that axle sleeve 81 and partition 8 be avoided to rotate again.
The above is only the preferred embodiment of the utility model only, is not intended to limit the utility model, all at this
Made any modifications, equivalent replacements, and improvements etc., should be included in the utility model within the spirit and principle of utility model
Protection scope within.
Claims (9)
1. a kind of mathematical education probability demonstration teaching aid, it is characterised in that: including round iron box, round iron bucket (3), several demonstration balls
(4), clamping screw, locking pin (6), multiple magnet (7), the round iron box include box body (1) and box cover, and the box cover includes
Round table-like lid (21) and cover rim (22), the side of the cover rim (22) and the top of box body (1) are hinged, the box body (1)
Bottom setting is in the inside of round iron bucket (3) and the bottom of box body (1) is connect with the screw top of round iron bucket (3)；The locking screw
Bolt includes bolt head (51) and screw rod (52), and the cassette bottom center of the box body (1) is provided be pierced by for screw rod (52) tail end
One through-hole (11), the box body (1) are internally provided with multiple partitions (8), and the outer cover of the screw rod (52) is equipped with and partition
(8) one-to-one axle sleeve (81), the side of the partition (8) are fixedly connected with the lateral wall of axle sleeve (81), the bolt head
(51) it is arranged in the top of axle sleeve (81), the outside of the box body (1) is additionally provided with the nut (9) matched with screw rod (52),
The nut (9) is threadedly coupled with screw rod (52)；The locking pin (6) includes square bar (61), round bar (62), rectangular baffle
(63), the head end of the tail end and round bar (62) of the square bar (61) is connected as one, and the round bar (62) and baffle (63) are mutual
Vertically, it is fixedly connected in the middle part of the tail end of the round bar (62) and baffle (63), the center of top of the lid (21) is provided with
The rectangular holding tank (211) matched with baffle (63), the slot bottom center of the holding tank (211) be provided with for square bar (61) and
The second through-hole of circle (212) of round bar (62) disengaging is provided at the top of the bolt head (51) and matches with square bar (61)
Rectangular blind hole (511).
2. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the box body (1)
Cassette bottom is additionally provided with the scale mark (12) for indicating angle, inside of scale mark (12) setting in box body (1).
3. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the round iron bucket (3)
Bucket bottom be provided with the groove for accommodating locking pin (6), the groove is located at the inside of round iron bucket (3), the inner wall of the groove
It is installed with spongy layer (31).
4. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the nut (9)
Outside is installed with handle (91).
5. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the bolt head (51)
Rubber sleeve (53) are additionally provided between axle sleeve (81).
6. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the axle sleeve (81) with
It is clearance fit between screw rod (52).
7. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the baffle (63) with
It is clearance fit between holding tank (211).
8. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the holding tank
(211) groove depth is greater than or equal to the thickness of baffle (63).
9. a kind of mathematical education probability demonstration teaching aid according to claim 1, it is characterised in that: the square bar (61) with
It is clearance fit between blind hole (511).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820372025.8U CN208781458U (en) | 2018-03-19 | 2018-03-19 | A kind of mathematical education probability demonstration teaching aid |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820372025.8U CN208781458U (en) | 2018-03-19 | 2018-03-19 | A kind of mathematical education probability demonstration teaching aid |
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| Publication Number | Publication Date |
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| CN208781458U true CN208781458U (en) | 2019-04-23 |
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| CN201820372025.8U Active CN208781458U (en) | 2018-03-19 | 2018-03-19 | A kind of mathematical education probability demonstration teaching aid |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110070783A (en) * | 2019-04-30 | 2019-07-30 | 河南大学 | A kind of statistics normal distribution demonstration teaching aid |
-
2018
- 2018-03-19 CN CN201820372025.8U patent/CN208781458U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110070783A (en) * | 2019-04-30 | 2019-07-30 | 河南大学 | A kind of statistics normal distribution demonstration teaching aid |
| CN110070783B (en) * | 2019-04-30 | 2021-01-12 | 河南大学 | Statistics normal distribution demonstration teaching aid |
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