CN201665075U - Chalk jacket - Google Patents

Abstract

The utility model discloses a chalk jacket which comprises a sleeve which wraps chalk; the end of the sleeve is provided with limiting pieces which are matched with the chalk in a sliding way; a base is screwed in the inner cavity of the sleeve; one end surface of the base is provided with a concave cavity which clamps the bottom of the chalk; and the other end of the base is provided with a groove. The limiting pieces are uniformly distributed on an elastic jaw on the end of the sleeve. The base is through hole for communicating the concave cavity and the groove. Pocks are uniformly distributed on the outer side surface of the sleeve. The chalk jacket can enhance the friction force on the outer surface of the sleeve, so that a teacher has better feeling when holding so as to prevent skidding. By adopting the structure, the chalk jacket has reasonable structure, is convenient to use, is applicable to various occasions on which the chalk is used, is particularly applicable to schools which use the chalk often or for a long time, not only is beneficial to protective the skin of a user but also is beneficial to improving the teaching quality.

Description

A kind of chalk sheath

Technical field

The utility model relates to a kind of chalk sheath.

Background technology

Chalk is the instrument that widely uses in the daily life, generally is used for book more and writes on the blackboard, so that the teacher in the school uses is more.The composition of chalk is calcium carbonate (lime stone) and calcium sulfate (gypsum), or contains a spot of calcium oxide, is white depositions, is not easy to be decomposed, and particle is bigger than dust, and the inspiration tracheae can be very uncomfortable, can cause nose, pharynx, larynx etc. to locate discomfort, may suffer from lung cancer.The teacher is in teaching process, generally all be directly to control chalk on blackboard, to write with hand, chalk has spread effect to skin membrane, if meet sweat and separate hot summer days, produce alkaline matter, just bigger to Mucocutaneous stimulation, because human body skin institute survival environment is a weak acid environment, under the effect of dust alkalescence, destroyed the basic living environment of skin like this, chalk dust makes skin become dry, coarse, and, make the human body discomfort with the sensation of scratching where it itches, severe patient can cause acne, folliculitis, pyoderma, chapped skin and a large amount of trichomadesis influence and have disturbed teacher's operate as normal and life.China Patent No. is that 200820062691.8 utility model patent discloses the special-purpose chalk holder of a kind of teacher, though can solving, the special-purpose chalk holder of this teacher directly controls the skin damage problem that chalk causes, but structural design must be complicated, cost is higher, also inconvenient during use, be unfavorable for improving the quality of teaching and popularization and application.

The utility model content

The technical problems to be solved in the utility model is to provide a kind of a kind of chalk sheath rational in infrastructure, easy to use at above-mentioned deficiency.

For solving the problems of the technologies described above, this chalk sheath comprises the sleeve pipe of suit chalk, and its design feature is: cannula tip is provided with the locating part that is slidingly matched with chalk, is bolted with base in the cannula cavity, base one end face is provided with the cavity that clamps the chalk bottom, and the base other end is provided with groove.

The chalk sheath of this structure comes implementation structure reasonable and easy to use by the suit helical structure.

The suit helical structure comprises sleeve pipe and base, sleeve pipe and base are the relations of being spirally connected, the base periphery is provided with external screw thread, internal surface of sleeve pipe is provided with the internal thread that matches with the base external screw thread, cannula tip is provided with locating part, and locating part can guarantee that chalk can both steadily skid off from cannula tip in chalk periphery when casing axis moves.The base end face is provided with groove, uses the screwdriver that matches with groove, can drive base and rotate in sleeve pipe, and like this, base just can move up at quill.The base end face is provided with cavity, cavity can be fastened with the chalk bottom, like this, the chalk outside is wrapped up by sleeve pipe, chalk top is spacing by locating part, and the chalk bottom is by base support, during use, only with hand is controlled sleeve pipe can play safe effect of controlling chalk, has avoided direct contact chalk and the skin injury that causes.When driving the base rotation, chalk will stretch out or indentation from cannula tip under the drive of base, has so just played the effect that the control chalk exposes casing length.Along with chalk writing on blackboard, chalk length constantly is consumed, and chalk exposes the length of sleeve pipe with shorter and shorter, like this, only needs rotating base can adjust the length that chalk exposes sleeve pipe, and is very easy to use.

As a kind of implementation, described locating part is the elastic card claw that is distributed on cannula tip.

It is coniform that the chalk of traditional structure generally all is, the chalk external diameter is up-small and down-big, uses elastic card claw as locating part, can guarantee that the top external diameter chalk different with following external diameter can both pass cannula tip smoothly, and can not produce and rock, guarantee teacher's stability in use.

As improvement, base is provided with the through hole that is communicated with cavity and groove.

Because the chalk sheath of this structure is installed on the chalk bottom in the base cavity, so, the chalk of cavity inside finally makes and can not be used, the through hole that is communicated with cavity and groove is set on base, can chalk be used the inner timesharing of only surplus cavity, utilize the diameter straight-bar littler that the chalk remainder is disclosed in cavity, new chalk so just can be installed reuse, help saving instruction cost than through hole.

As improvement, be evenly equipped with pit on the outside of sleeve face.

On the outside of sleeve face pit is set, can strengthens the frictional force of bushing outer surface, the teacher more has feel when controlling, prevent skidding.

In sum, adopt the chalk sheath of this structure, rational in infrastructure, easy to use; the occasion that is adapted at various use chalks is used; be particluarly suitable for using often or for a long time in the school of chalk and use, both helped protecting user's skin, help again improving the quality of teaching.

Description of drawings

In conjunction with the accompanying drawings the utility model is described in further details:

Fig. 1 is a structural representation of the present utility model.

Among the figure: 1 is chalk, and 2 is sleeve pipe, and 3 is base, and 4 is cavity, and 5 is groove, and 6 is claw, and 7 is through hole, and 8 is pit.

The specific embodiment

As shown in Figure 1, this chalk sheath comprises sleeve pipe 2, and sleeve pipe 2 is straight tube-like, the cross section of sleeve pipe 2 is an annular, and sleeve pipe 2 inwalls are provided with internal thread, are bolted with base 3 in the sleeve pipe 2, base 3 is cylindric, and the side of base 3 is provided with the external screw thread that matches with sleeve pipe 2 internal threads, and base 3 lower surfaces are provided with groove 5, in the present embodiment, groove 5 is a yi word pattern, in use, straight screwdriver is inserted in the groove 5, rotary screw cutter handle can drive base 3 and rotate along sleeve pipe 2 inwalls then.Base 3 upper surfaces are provided with the cavity 4 to lower recess, cavity 4 internal diameter sizes match with chalk 1 bottom external diameter, chalk 1 bottom can be clamped in the cavity 4, like this, when base 3 when sleeve pipe 2 rotates, chalk 1 will stretch out outside sleeve pipe 2 or indentation in sleeve pipe 2 under the drive of base 3, and it is very convenient to operate.Also be provided with the through hole 7 that is communicated with cavity 4 and groove 5 on the base 3, in through hole 7, insert straight-bar, the chalk 1 that is installed in the cavity 4 can be disclosed, also very convenient when changing chalk 1.

Sleeve pipe 2 upper ends also are provided with claw 6, claw 6 be distributed on sleeve pipe 2 ends and with chalk 1 outer peripheral face snap-fit, claw 6 has elasticity, when chalk 1 axial when protruding at the promotion lower edge of base 3 sleeve pipe 2, claw 6 can be expanded with the continuous expansion of chalk 1 external diameter, thereby guarantees that chalk 1 top and sleeve pipe 2 upper ends stably are pressed together, like this, when controlling sleeve pipe 2, just be equivalent to control chalk 1 itself.Sleeve pipe 2 outsides are evenly equipped with pit 8, and pit 8 can strengthen the frictional force when controlling, and have both strengthened and have controlled feel, have avoided again directly controlling chalk 1 and injury that human body skin is caused.

Claims (5)

1. chalk sheath, the sleeve pipe (2) that comprises suit chalk (1), it is characterized in that: sleeve pipe (2) end is provided with the locating part that is slidingly matched with chalk (1), be bolted with base (3) in sleeve pipe (2) inner chamber, base (3) one end faces are provided with the cavity (4) that clamps chalk (1) bottom, and base (3) other end is provided with groove (5).

2. chalk sheath as claimed in claim 1 is characterized in that: described locating part is for being distributed on the elastic card claw (6) of sleeve pipe (2) end.

3. chalk sheath as claimed in claim 1 or 2 is characterized in that: base (3) is provided with the through hole (7) that is communicated with cavity (4) and groove (5).

4. chalk sheath as claimed in claim 1 or 2 is characterized in that: be evenly equipped with pit (8) on sleeve pipe (2) lateral surface.

5. chalk sheath as claimed in claim 3 is characterized in that: be evenly equipped with pit (8) on sleeve pipe (2) lateral surface.