CN103057309A - Chalk case - Google Patents

Abstract

The invention provides a chalk case. The chalk case comprises an outer casing, an inner casing and two crawler belts, a plurality of snapping teeth are arranged at the lower end of the inner side wall of the outer casing, limiting bars are disposed at the upper ends of the inner side walls of the outer casing, a chalk penetrates through the inner casing, through holes are arranged on two corresponding side walls of the inner casing respectively, bearings are fixedly arranged at positions of the through holes, retaining bars located above the through holes are arranged on the outer side of the inner casing, the retaining bars are located below the limiting bars, the inner casing penetrates through the outer casing, a spring is arranged between the inner casing and the outer casing, a plurality of driving teeth are disposed on the crawler belts, the driving teeth are matched with the snapping teeth, and the crawler belts penetrate through the bearings and the bottom end of the inner casing to be tightly attached to the chalk. The chalk case has the advantages that the structure is simple, the usage is convenient, hygienic and resource-saving effects are achieved, a good learning environment is created for students, and direct harm to skin is reduced.

Description

Chalk sleeve

Technical field

The present invention relates to a kind of realia, refer in particular to a kind of chalk sleeve.

Background technology

Along with popularizing of compulsory education, set up between urban and rural areas increasing school, the thing followed is the increase of the use amount of chalk, and the chalk that present most teacher uses on class all is directly to grab writing on hand, the injury of the upper skin of long-term in the past adversary is very large, and write last remaining segment chalk end and can not re-use, caused the waste of resource.

Summary of the invention

For overcoming the existing defective of prior art, but now provide the chalk sleeve of a kind of sandwiched chalk and a controlled powder process length.

Chalk sleeve of the present invention, it comprises:

One shell body, the madial wall lower end of described shell body is provided with plural latch, and its madial wall upper end is provided with a positive stop strip;

One inner housing, described chalk is arranged in described inner housing, the corresponding two side of described inner housing offers respectively a through hole, described lead to the hole site is installed with a bearing, the outside of described inner housing is provided with a screens bar in described through hole top, and described screens bar is positioned at the below of described positive stop strip, and described inner housing is arranged in the described shell body, and is provided with a spring between described inner housing and the described shell body;

Two crawler belts, described crawler belt is provided with plural driving gear, and described driving gear cooperates with described latch, and described crawler belt is arranged in the bottom of described bearing and described inner housing and is close to chalk.

Top one side of described inner housing forms the leader.

Driving gear on the described crawler belt is pawl.

In use, at first the top of chalk from inner housing penetrated, by two crawler belts chalk is clamped, can use the chalk-writing that exposes the shell body bottom, when the bottom chalk is about to be finished, handle can be pushed downwards, make shell body up mobile, latch slides against driving gear, thereby driving crawler belt inwardly rotates, chalk is also released downwards thereupon, then unclamps handle, by spring shell body is resetted downwards, because the driving gear on the crawler belt is pawl, therefore the shell body Shi Buhui that resets downwards drives the crawler belt rotation, and it is mobile that the effect that is subject to simultaneously positive stop strip and screens bar stops shell body, just finished the operation of release chalk.Chalk sleeve of the present invention is simple in structure, easy to use, has reached the effect of health, saving resource, has created good academic environment to the student, and has reduced the direct injury to skin.

Description of drawings

Fig. 1 is the shell body profile of chalk sleeve of the present invention;

Fig. 2 is the inner housing profile of chalk sleeve of the present invention;

Fig. 3 is the bearing portions enlarged drawing of chalk sleeve of the present invention;

Fig. 4 is the overall structure profile of chalk sleeve of the present invention;

Fig. 5 is the profile of chalk sleeve of the present invention when pushing downwards;

Fig. 6 is the generalized section after chalk sleeve of the present invention unclamps handle.

The specific embodiment

For the benefit of to the understanding of structure of the present invention, describe below in conjunction with drawings and Examples.

In conjunction with Fig. 1 and shown in Figure 2, chalk sleeve of the present invention, it comprises:

One shell body 1, the madial wall lower end of shell body 1 is provided with plural latch 11, and its madial wall upper end is provided with a positive stop strip 12;

One inner housing 2, chalk 3 is arranged in the inner housing 2, inner housing 2 corresponding two sides offer respectively a through hole 21, the position of through hole 21 is installed with a bearing 6, bearing 6 is ball bearing, as shown in Figure 3, the outside of inner housing 2 is provided with a screens bar 22 in through hole 21 tops, and screens bar 22 is positioned at the below of positive stop strip 12, prevent in use coming off of shell body 1, inner housing 2 is arranged in the shell body 1, and top one side of inner housing 2 forms leader 23, and be provided with a spring 4 between inner housing 2 and the shell body 1, in order to control resetting of shell body 1;

Two crawler belts 5, crawler belt 5 are provided with plural driving gear 51, and driving gear 51 is pawl and cooperates with latch 11, and crawler belt 5 is arranged in the bottom of bearing 6 and inner housing 2, and crawler belt 5 is located between the ball 61 of bearing 6 and with chalk 3 to be close to, in order to control the flexible of chalk 3.

Extremely shown in Figure 6 in conjunction with Fig. 4 again, when using chalk sleeve of the present invention, at first the top of chalk 3 from inner housing 2 penetrated, by two crawler belts 5 chalk 3 is clamped, can use the chalk 3 that exposes shell body 1 bottom to write, when bottom chalk 3 is about to be finished, the handle 23 on inner housing 2 tops can be pushed downwards, make shell body 1 up mobile, latch 11 slides against driving gear 51, thereby driving crawler belt 5 inwardly rotates, because crawler belt is located between the ball, so crawler belt can not slide easily, and chalk is also released downwards thereupon, then unclamp handle 23, by spring 4 shell body 1 is resetted downwards, because the driving gear 51 on the crawler belt 5 be pawl, so shell body 1 Shi Buhui that resets downwards drives crawler belt 5 and rotates, the effect that is subject to simultaneously positive stop strip 12 and screens bar 22 makes shell body 1 stop to move, and has just finished the operation of releasing chalk 3.When if chalk 3 is about to use, chalk 3 can be taken out, what more renew gets final product.

Chalk sleeve of the present invention is simple in structure, easy to use, has reached the effect of health, saving resource, has created good academic environment to the student, and has reduced the direct injury to skin.

Claims (3)

1. chalk sleeve is characterized in that comprising:

One shell body, the madial wall lower end of described shell body is provided with plural latch, and its madial wall upper end is provided with a positive stop strip;

One inner housing, described chalk is arranged in described inner housing, the corresponding two side of described inner housing offers respectively a through hole, described lead to the hole site is installed with a bearing, the outside of described inner housing is provided with a screens bar in described through hole top, and described screens bar is positioned at the below of described positive stop strip, and described inner housing is arranged in the described shell body, and is provided with a spring between described inner housing and the described shell body;

Two crawler belts, described crawler belt is provided with plural driving gear, and described driving gear cooperates with described latch, and described crawler belt is arranged in the bottom of described bearing and described inner housing and is close to chalk.

2. chalk sleeve according to claim 1 is characterized in that: the top one side formation leader of described inner housing.

3. chalk sleeve according to claim 1, it is characterized in that: the driving gear on the described crawler belt is pawl.

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