| Writing instrument -> Monitor Keywords |
|
|
 
Writing instrumentRelated Patent Categories: Coating Implements With Material Supply, With Means To Attach Or Conform To Body Of UserWriting instrument description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070154253, Writing instrument. Brief Patent Description - Full Patent Description - Patent Application Claims
BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a writing instrument in which a sleeve made of an elastic soft material is attached at least at a gripping portion of a barrel for accommodating a writing body. [0003] 2. Description of the Related Art [0004] Conventionally, various writing instruments, in which a sleeve formed in a cylindrical shape by an elastic resin material is attached to a gripping portion of a barrel have been proposed and sold in the market. Some of the writing instrument, in which the sleeve made of an elastic resin material is merely attached on the outer circumferential surface of the barrel depends for its elasticity only on the elastic characteristic of the sleeve itself when being gripped. Therefore, a problem is that a sufficient gripping force absorbing effect or gripping feeling improvement effect can not be obtained. Also, when the elastic resin material is hardened after long time of use, the effects are further deteriorated. [0005] On the other hand, a writing instrument disclosed e.g. in the Japanese Utility Model Laid-Open No. 63-60375, has a plurality of projected ribs extending in the axial direction are formed on the inner circumferential surface of the sleeve and a projecting end of the projected rib is brought into contact with the outer circumferential surface of the barrel in order to improve gripping feeling. By this, a gap portion is formed between the inner circumferential surface of the sleeve and the outer circumferential surface of the barrel. Because of existence of this gap portion, the sleeve can be deformed to sink into the gap portion when the sleeve is gripped so that the gripping feeling is improved. [0006] However, with the writing instrument in this gazette, a connecting force of the sleeve to the barrel is weak, and a problem is that the sleeve is easily moved relative to the barrel when it is gripped. [0007] In response to the above-described problem, in the writing instrument disclosed in the Japanese Patent No. 3464791, a thickness of a peripheral wall of the sleeve is set to be large, a plurality of gap portions penetrating the peripheral wall in the axial direction are formed and the gap portions are arranged in the circumferential direction. [0008] According to the writing instrument described in the above-described gazette, when the sleeve is gripped, the outer circumferential surface of the sleeve is elastically deformed easily by the existence of the plural gap portions in the sleeve peripheral wall, and moreover, deformation is not generated on the inner circumferential surface of the sleeve and thus, slip between the inner circumferential surface of the sleeve and the barrel outer circumferential surface is not caused. [0009] However, even in the writing instrument in this gazette, the inner circumferential surface of the sleeve is merely in contact with the outer circumferential surface of the barrel, and the position is maintained merely by a frictional force of the sleeve, and therefore, a problem is that the slip of the sleeve with respect to the barrel can not be fully prevented. SUMMARY OF THE INVENTION [0010] In view of the foregoing and other drawbacks, disadvantages and problems of the conventional methods and structures, an object of the present invention is to provide a writing instrument which can improve gripping feeling of a sleeve without slip of the sleeve with respect to a barrel. [0011] In order to achieve the above-described object, a writing instrument according to the present invention comprises a barrel for accommodating a writing body and a sleeve attached to the outer circumferential surface of the barrel and made of an elastic soft material, in which a plurality of first engaging portions extending in the axial direction and projecting in the direction of the inner diameter are provided on the inner circumferential surface of the sleeve, second engaging portions to be engaged with the first engaging portion is formed on the outer circumferential surface of the barrel, and a gap portion is formed between the adjacent first engaging portions between the sleeve and the barrel. [0012] Mutual engagement between the first engaging portion formed on the sleeve and the second engaging portion formed on the barrel disables relative rotation of the sleeve with respect to the barrel. By this, slip of the sleeve in the rotating direction with respect to the barrel is prevented. [0013] When a user grasps a gripping portion of the writing instrument, the sleeve can sink into the gap portion and be deformed, and the gripping feeling can be improved. Also, slip of fingers can be prevented by this deformation. [0014] The outer profile shape of the cross section of the sleeve can be a non-circular polygonal shape including a triangle, and the above-described first engaging portion can be formed on the inner circumferential surface portion corresponding to an angle portion of the polygonal shape. The polygonal shape may be optional, but a triangular shape is advantageous since it corresponds to the number of commonly used gripping thumb and fingers. The above-described polygonal shape can be constituted by side portions and angle portions. The side portion has a small curvature but it does not have to be a straight line, while the angle portion has a large curvature but it does not have to be sharp. [0015] The outer profile shape of the cross section of the sleeve can be varied according to the position in the axial direction. By this, different gripping feelings according to the gripping position in the axial direction can be obtained, and a user can choose the gripping position in the axial direction so that a favorite gripping feeling can be obtained. [0016] The outer profile shape of the cross section of the sleeve can be varied so that the proportion shared by the side portion of the above-described polygonal shape is continuously increased from the front toward the rear. By this, different gripping feelings according to the position in the axial direction can be given to the user and moreover, design of the writing instrument can be improved. [0017] The barrel can include a front barrel to which the above-described sleeve is attached and a rear barrel which is located in the rear of the front barrel, and the outer profile shape of the cross section of the above-described rear barrel can conform to the outer profile shape of the rear end of the above-described sleeve forming the non-circular polygonal shape of triangle or a shape with more than three angles. By this, the sleeve conforms to the portion of the barrel to which the sleeve is not attached and the design of the writing instrument can be improved. [0018] A clip can be mounted to the rear barrel, and the clip can be mounted at the circumferential position aligning with one of the angle portions of the polygonal shape of the cross section of the sleeve and one of the angle portions of the polygonal shape of the cross section of the rear barrel. [0019] It is preferable that the second engaging portion of the barrel projects from the outer circumferential surface of the barrel toward the outer diameter, and by this, the shape of the first engaging portion of the sleeve can be maintained by the second engaging portion and the shape of the gap portion can be supported by the second engaging portion of the barrel, which can prevent crush of the gap portion due to aged deterioration. BRIEF DESCRIPTION OF THE DRAWINGS [0020] The foregoing and other purposes, aspects and advantages will be better understood from the following detailed description of preferred embodiments of the invention with reference to the drawings, in which: [0021] FIG. 1 is a side view showing an embodiment of a writing instrument according to the present invention; Continue reading about Writing instrument... Full patent description for Writing instrument Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Writing instrument patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Writing instrument or other areas of interest. ### Previous Patent Application: Member mounting arrangement Next Patent Application: Mounting apparatus using ball and socket joints with gripping features Industry Class: Coating implements with material supply ### FreshPatents.com Support Thank you for viewing the Writing instrument patent info. IP-related news and info Results in 0.64212 seconds Other interesting Feshpatents.com categories: Qualcomm , Schering-Plough , Schlumberger , Seagate , Siemens , Texas Instruments , 174 |
 * Protect your Inventions * US Patent Office filing 
PATENT INFO |
|
