1. Field of the Invention
The present invention relates to a punching device, especially to an adjustable punching device.
2. Description of Prior Art
The prior art punching device generally includes a base, two through holes defined on the base, two knife stages arranged on the base and corresponding to the through holes, and a pressing plate pivotally arranged on the base and corresponding to the knifes. When the pressing plate is pushed down to press on the top of the knife, the knife is also pushed downward on the through holes. Therefore, two holes can be made with predetermined separation on paper.
The above-mentioned punching device can punch two holes with predetermined separation on paper. However, when user wants to punch additional two or three holes, the third hole might have different separation with the other two holes. It is not suitable for practical use. The user is forced to buy a punching device for three holes. It is not convenient for user.
The present invention is intended to provide a punching device with new design, which allows user to punch holes with equal separation after the hole separation is set.
Accordingly, the present invention provides an adjustable punching device, which includes a base having a first through hole, a second through hole, a third through hole and a fourth through hole with predetermined separation, a first clamping section and a second clamping section adjacent to the third through hole and the fourth through hole. A fixed knife rack is arranged on each side of the base. The knife for each knife rack is corresponding to the first through hole and the second through hole. A lateral panel is arranged on outer side of the fixed knife rack. A pressing plate is pivotally connected between the lateral panels. A movable knife stage is arranged between two fixed knife racks. The movable knife stage is limited between the first clamping sections and on the second clamping sections. The movable knife rack is corresponding to the third through hole and the fourth through hole. After the hole separation has been adjusted, the pressing plate is pressed to punch holes with fixed separation.
The features of the invention believed to be novel are set forth with particularity in the appended claims. The invention itself however may be best understood by reference to the following detailed description of the invention, which describes certain exemplary embodiments of the invention, taken in conjunction with the accompanying drawings in which:
With reference to
The stage 1 includes a first through hole 11 and a second through hole 12 on both sides thereof. A third through hole 13 and a fourth through hole 14 with predetermined separation are provided between the first through hole 11 and the second through hole 12. First camping section 15, 15a and second camping sections 16, 16a are provided beside the third through hole 13 and the fourth through hole 14. The first camping section 15, 15a are blocks to limit the movement of the knife stage 2, and the second camping sections 16, 16a are projections to clamp the knife stage 2. Two fixed knife racks 17, 17a are arranged on both sides of the base 1 and each of the fixed knife racks 17, 17a is provided with a spring element 171, 171a. The spring elements 171, 171a are capped on the knifes 172, 172a corresponding to the first through hole 11 and the second through hole 12. Lateral panels 18, 18a are provided outside the fixed knife racks 17, 17a and include coupling holes 181, 181a for pivotally connecting to the pressing plate 3. A lower cover 19 is provided below the base 1 and includes an adjustable positioning rod 191.
The movable knife stage 2 is arranged between the fixed knife racks 17, 17a and is fixed to the base 1 by screwing a screw unit 21 with a nut 22 and a tab 23, where the screw unit 21 passes a pivotal hole 20. A knife 25 with a spring element 24 is provided in the movable knife stage 2. Clamping holes 26 corresponding to the second camping sections 16, 16a are defined on bottom of the movable knife stage 2. After the position of the movable knife stage 2 is adjusted, the clamping holes 26 can be posited corresponding to the second camping sections 16, 16a and the knife 25 is corresponding to the third through hole 13 or the fourth through hole 14.
The pressing plate 3 includes holes 31, 31a corresponding to the coupling holes 181, 181a of the lateral panels 18, 18a. A pivotal unit 32 passes the holes 31, 31a such that the pressing plate 3 is pivotally connected to the lateral panels 18, 18a. The pressing plate 3 includes a pressing section 33 for pressing against top of the knifes 172, 172a, 25, where the pressing section 33 has one convex face and a concave face.
With reference to
More particularly, the movable knife stage 2 according to the present invention can be applied to any punching device for punching more than two holes, whereby user can punch multiple holes with equal separation.
Although the present invention has been described with reference to the preferred embodiment thereof, it will be understood that the invention is not limited to the details thereof. Various substitutions and modifications have suggested in the foregoing description, and other will occur to those of ordinary skill in the art. Therefore, all such substitutions and modifications are intended to be embraced within the scope of the invention as defined in the appended claims.