Field of the Invention
The present invention is related to a cutter knife, which can be surely prevented from being entered into other products as a foreign substance.
Description of the Related Art
For example, regarding products of mattress or stuffed toy animal, sometimes a cutter knife used during manufacturing process may remain in the products as a foreign substance. The cutter knife as the foreign substance is to be found by a metal detector and taken out.
For surely being found by a metal detector, the cutter knife may preferably include many metal components. Theoretically, even a common cutter knife, the body of which is made of plastics, could found by a metal detector, because the blade of which is made of metal. But actually, a cutter knife having less metal components could path by the metal detector, without being found.
In order to optimally be found by the metal detector, the whole of a cutter knife including its body would be all made with metal parts. The cutter knife made with only metal parts has been already put on the market by the applicant, and was also published in a Japanese magazine of Weekly MAINICHI-GRAPH of Oct. 7, 1979.
However, if the whole of a cutter knife is made with metal parts only, there may be a problem, that is, smoothness of sliding operation of the cutter knife blade could be degraded in time because of friction and the like, particularly in a type of a cutter knife wherein its blade is extended and retracted in a sliding manner. In order to prevent this, lubricating oil or friction resistant coating may be applied, but it could bring another problem, below.
That is, because of the lubricating oil, products of mattress or stuffed toy animal could get dirty, or otherwise, there may be a sanitary problem when the cutter knife is used in the field of foods. Further, applying the friction resistant coating could increase the manufacturing cost.
An object of the present invention is to provide a cutter knife, having a blade within its body slidably extended from or retracted into the body, in which even if the cutter knife is made with only the metal parts, smoothness of sliding operation of the cutter knife blade is not degraded in time, even without lubricating oil or friction resistant coating.
In order to achieve the objects of the present invention, there is provided a cutter knife comprising:
a cutter knife body,
a knife blade, which is slidably held in the cutter knife body, and
a slider, via which the knife blade is operated to extend from or retract into the cutter knife body,
wherein at least one of the knife blade and the slider is supported, at a position where the knife blade and/or the slider is made contact with the cutter knife body, by a rolling member which reduces frictional interference.
Note that, in the present invention, the word “rolling member” means anything, with which frictional interference can be lowered taking advantage of its rolling action, for example, a column, a cylinder, a sphere or the like.
With the cutter knife of the present invention, constructed as above, regarding the knife blade and the slider, which slide relatively to the cutter knife body, at least one of which (preferably both) is supported by a rolling member which reduces frictional interference, at a position where the knife blade and/or the slider is made contact with the cutter knife body.
Thus, even if the whole of the cutter knife is made with metal parts only, without lubricating oil nor friction resistant coating, the smooth sliding operation of the slider can be realized for long time in use.
In other words, by making the cutter knife with metal parts only, the cutter knife would be surely sensed by a metal detector. Furthermore, without lubricating oil nor friction resistant coating, the smooth sliding operation of the slider can be realized for long time in use.
Thus, thanks to the present invention, a cutter knife, of which the smooth operation is not degraded for long time in use, can be made with metal parts only, and thus, such the cutter knife can be surely sensed by a metal detector.
But note that, in the present invention, it is not necessary needed to make the cutter knife with 100% only metal parts, and partially other materials could be used in some portion of the cutter knife to some extent, as long as actually no problem is brought.
These and other objects and features of the present invention will become apparent from the following description taken in conjunction with the preferred embodiments thereof with reference to the accompanying drawings.
Before the description of the embodiments proceed, it is to be noted that like or corresponding parts are designed by like reference numerals throughout the accompanying drawings.
Referring to
A user operates the slider 30, which is mounted outside of the cutter knife body, to extend the blade 20 from the cutter knife body 11 and to retract the blade 20 into the body 11. The slider 30 is being urged in the direction of retracting the blade 20, by the spring 40 mounted inside the cutter knife body 11 (see
The cover member 45 is to be attached to the cutter knife body 11, such that the cover member 45 extends over the sliding member 31. Thanks to this cover member 45, the smooth sliding operation of the sliding member 31 is ensured, even when the cutter knife 10 is grasped in hand.
The sliding member 31 and the cutter knife body 11 are connected with each other by the spring 40. With the spring force of the spring 40, the slider 30 is urged in the direction of retracting the blade 20. That is, as shown in
As best shown in
The height of the protrusions 35, 36 is determined, such that their tips 35a, 36a do not touch with the inner surface 15a of the cutter knife body 11 in an assembled up condition of the cutter knife 10. Thanks to such the construction, when the slider 30 slides along with the cutter knife body 11, the protrusion tips 35, 36 are surely prevented from interfering with the inner surface 15a of the cutter knife body 11, and thus realizing the smooth sliding operation.
Note that although in the shown embodiment two protrusions 35, 36 are made engaged into the holes formed on the blade, the number of the protrusions can be conveniently selected.
In the shown embodiment, the slider 30 is a member having a cross sectional view of U-shape, which comprises the top wall 30a and opposed two side walls 30b, 30c, and in which the space of U-shape, a column (rolling member) 50 is carried so as to freely roll. In order prevent unwillingly fall off of the column 50 from the slider 30 while allowing the column 50 to freely roll, there are provided stop walls 30d, 30e at the both ends of the top wall 30a, and the receiving wall 30f at the lower end of the side wall 30b.
Generally speaking, when operating the slider 30 with a finger, gripping the cutter knife 10 in hand, the external force applied from the finger to the slider 30 will act in the direction of pushing the slider 30 onto the outer wall of the cutter knife body 11 (arrow “A”,
The heights of the protrusions 35, 36 which connect the slider 30 and the blade 20 are designed, such that their tips 35a, 36a do not reach the inner surface 15a of the cutter knife body 11. Thus, even if an external force is applied onto the slider 30 in the direction of the arrow “A” in
Further, since such the protrusions 35, 36 are engaged into the holes 25, 26 formed on the blade 20 to connect the slider 30 and the blade 20, the external force “A” (
Thanks to the above factors (I)-(III) together, in the present invention, even if the whole of the cutter knife is made with metal parts only, the smooth sliding operation of the slider 30 (that is, smooth extending out and retracted into) can be realized for long time in use. For that, lubricating oil or friction resistant coating is not needed.
Thus, thanks to the present invention, a cutter knife, of which the smooth operation is not degraded for long time in use, can be made with metal parts only, and thus, such the cutter knife can be surely sensed by a metal detector. Note that it is not necessary needed to make a cutter knife with 100% only metal parts, and partially other materials could be used.
In the shown embodiment, a column is employed as the rolling member 50 and its rolling action is taken advantage of. But, as long as the same effect is obtained, a cylindrical member, a spherical member and the like can be used. Depending on the specific configuration of the rolling member, the configuration of the slider 30 would be changed, such that the rolling member is carried so as to freely roll while unwilling fall off of the slider 30 is prevented.
in the shown embodiment, the wall 15, which is opposed to the wall on which the slider 30 is mounted, is raised outwardly, and due to such the raise the inner surface 15a of the cutter knife body 11 is depressed outwardly. The protrusion tips 35a, 36a terminate in the space 16 formed by the depression, and thanks to this, the protrusion tips 35a, 36a are prevented from interfering with (touching) the inner surface 1Sa of the cutter knife body 11. Simultaneously, thanks to the moderate raise of the wall 15, ease of grasping the cutter knife and of handling the same can be improved.
Note that the raise of the wall 15 is not necessary needed, and for example, the wall 15 could be made flat and the heights of the protrusions 35, 36 could be adjusted so as not to touch the inner surface of the wall 15.
In the first embodiment (
On the contrary, in the second embodiment, the rolling member 50′ is located at the tip of the protrusion 35, thereby preventing interference between the protrusion tip 35a and the inner surface 15a. Although the location of the rolling member 50′ is schematically shown in
In the second embodiment shown in
In the second embodiment, the force acting in the direction of the arrow “A” onto the slider 30 is received by the rolling member 50, and thus, the rolling member 50 carried by the slider 30 could be omitted. But, in such the case, there may be preferably provided a suitable gap, between the slider 30 and the outer surface of the cutter knife body 11.
On the upper wall, the slider 30 is slidably mounted, and the protrusions 35, 36 extend downwardly from the sliding member 31, which slide together with the slider 30. These protrusions 35, 36 are made engaged into the holes 25, 26 formed on the blade 20.
The above basic configuration in the third embodiment is the same as those in the first and second embodiments, which were already explained.
The third embodiment is different from the first and second embodiments in that rolling members 51 (blade-support rolling member) are provided between the lower surface of the blade 20 and the lower wall. The blade-support rolling members 51 are to support the blade surface far from the slider 30 with rolling contact on it, thereby securing the smooth sliding operation of the blade 20.
As is explained above, thanks to the construction of the first or the second embodiment, the blade 20 is prevented from being pressed onto the bottom wall of the cutter knife by the external force acting on the slider 30. But, there may be a possibility that some other unwilling external force via another route would act on the blade 20. Even in such the case, thanks to the existence of the blade-support rolling member 51, frictional interference between the blade 20 and the bottom wall of the cutter knife could be prevented, thereby securing the smooth sliding operation.
The construction shown in
As the blade-support rolling member 51, a column, a cylinder, a sphere or the like suitable could be employed, as long as with which the friction can be lowered taking advantage of rolling contact. Such the blade-support rolling member 51 would be mounted in a suitable manner and at a suitable location. Further, the blade-support rolling members 51 are preferably provided in plural along with the sliding direction of the blade 20, as shown in
Here, in between the sliding member 31 and the cover member 45, a plurality of rolling members 52 (sliding-member-support rolling member) are provided along with the longitudinal direction of the sliding member 31.
The sliding member 31 is supported by the plurality of sliding-member-support rolling members 52, which are provided along with the longitudinal direction of the sliding member 31. In other words, the sliding member is supported by rolling members at discrete several points along with the longitudinal direction of the sliding member 31. Therefore, even if an external force acting in the direction of the arrow “A” is applied onto the slider 30 which is located at the end of the sliding member 31, the sliding member 30 would scarcely be inclined to its sliding direction (if the inclination of the sliding member 31 occurs, the blade 20 existing below the sliding member 31 may be pressed onto the bottom wall of the cutter knife body, and thus not preferable).
In the embodiment shown in
As the sliding-member-support rolling member 52, a column, a cylinder, a sphere or the like suitable could be employed, as long as with which the friction can be lowered taking advantage of rolling contact. Such the sliding-member-support rolling member 52 would be mounted in a suitable manner and at a suitable location.
Although the present invention has been fully described in connection with the preferred embodiment thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications are apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims unless they depart therefrom.
Number | Date | Country | Kind |
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2015-173102 | Sep 2015 | JP | national |