WO2006012595A2

WO2006012595A2 - Spring actuated stapler

Info

Publication number: WO2006012595A2
Application number: PCT/US2005/026261
Authority: WO
Inventors: Michael P. Joyce; Brent Lucas
Original assignee: Joyce Michael P; Brent Lucas
Priority date: 2004-07-23
Filing date: 2005-07-22
Publication date: 2006-02-02
Also published as: JP4812761B2; BRPI0512426A; CA2574774A1; EP1778441A2; AU2005266928A1; EP1778441A4; JP2008507420A; MX2007000926A; AU2005266928B2; WO2006012595A3; CA2574774C

Abstract

The stapling apparatus comprises a striking plate (123) for individually dispensing the staples (126) upon actuation by a striker spring (120), and a triggering mechanism for triggering the actuation of the striker spring (120). In an embodiment, the triggering mechanism comprises an triggering lever (110) which engages with the striker spring (120) to lift the striking plate (123), and, when actuated by a release bar (132), disengages itself from the striking plate (123) to release the striking plate (123).

Description

SPRINGACTUATEDSTAPLER

Technical Field

The present invention relates to a stapling apparatus, and more particularly, to a spring actuated stapler with a simplified triggering mechanism.

Background Art

In a spring-actuated stapler, a striking plate is reciprocally movable between an initial position and a fire position. When the striking plate moves from the initial position to the fire position, a striker spring, which is engaged with an opening in the striking plate, is deformed and energized. When the striking plate reaches the fire position, the striker spring is released to resume its initial shape, in the process driving the striking plate to its initial position to dispense to a work piece a leading staple of a stable stick contained in a staple magazine. An actuation lever is provided to pull, either though a direct engagement with the striking plate or through an engagement with the striker spring (which may be a leaf spring), the striking plate from the initial position to the fire position when a force is applied on a cover plate of the stapler during a stapling operation. When the striking plate reaches the fire position, the actuation lever disengages itself from the striking plate or from the striker spring, so that the striking plate is driven back from the fire position to the initial position by the striker spring. There are numerous spring actuation mechanisms to carry out the above operations, however, efforts have never stopped in designing better ones with improvement in simplicity, preciseness and reliability.

Disclosure of Invention

The present invention is directed to a stapling apparatus with a novel spring actuated mechanism.

According to a first aspect of the present invention, a lever running most of the length of the entire stapler is used to load the spring, providing a relatively large loading force with a relatively low amount of user applied pressure, due to the leveraging.

In an exemplary embodiment, the stapling apparatus of the present invention comprises a base member and a magazine member for accommodating a set of staples or a staple stick therein, each member having a first end and a second end, the two members being pivotally connected to each other at the first ends, a striking plate for individually dispensing the staples upon actuation by a striker spring, and a triggering mechanism for triggering the actuation of the striker spring. More specifically, as taught by the present invention, the triggering mechanism comprises a triggering lever arranged between the base member and the magazine member such that the triggering lever triggers the actuation of the striker spring when the second ends of the two members are moved toward each other. With the triggering lever provided between the base member and the magazine member, the design of the stapler is simplified and utilizes a much smaller number of components.

Preferably, the triggering lever is made of a resilient material, and has a lower end secured to an upper surface of the base member and an upper end freely abutting against an under surface of the staple magazine, whereby normally biasing the second ends of the two members away from each other by a proper distance for accepting a work piece. Thus, the stapler of the present invention may not need an additional raiser element to keep the distance between the base member and the magazine member.

Preferably, the striking spring has a first end to engage with an opening formed on the striking plate for moving the striking plate between a first position and a second position, and the triggering lever engages with the striker spring to force the striker spring to deform during a stapling operation whereby the striker spring brings the striking plate from the first position to the second position. No direct engagement is needed between the triggering lever and the striking plate, thereby simplifying the design of the stapler. Preferably, a release mechanism is provided to release the engagement between the triggering lever and the striker spring when the striking plate reaches the second position, whereby the striker spring resumes its initial shape and thus powerfully drives the striking plate back to the first position for dispensing a leading one of the staples.

Alternatively, similar to the prior art, the triggering lever may directly engage with the striking plate but not with the striker spring. However, the cover plate in the prior art may be omitted with the teaching of the present invention.

According a second aspect of the present invention, a stapler with a novel leaf spring actuation mechanism is provided. According to the teaching of the present invention, the stapler comprises a striking plate for dispensing a staple from a staple magazine, a leaf spring engaged with the striking plate for driving said striking plate, and an actuation bar for lifting the leaf spring from a first position to a second position whereby lifting the striking plate from an initial position to a release position in which the leaf spring is released from the actuation bar to powerfully drive the striking plate towards the initial position.

In a preferred embodiment, the actuation bar comprises a laterally protruding lug which is adapted to push upward a tab provided on the leaf spring so as to lift the leaf spring when an external force is applied to the actuation bar. Preferably, the tab disengages itself from the lug when the leaf spring reaches the second position where the striking plate is lifted to the release position.

Preferably, the actuation bar has a front end movable along a guiding ramp when the external force is applied to the actuation bar, thus improving reliability and accuracy of the engagement between the lug of the actuation bar and the tab of the leaf spring.

Preferably, the engagement between the tab and the lug is such that the tab slides on an upper surface of the lug towards an edge of the lug when the front end of the actuation bar moves along the guiding ramp, and drops from the edge of the lug when the leaf spring reaches the second position, whereby releasing the leaf spring from the actuation bar.

Brief Description of Drawings

The above and other features and advantages of the present invention will be clearer by reading the detailed descriptions of the preferred embodiments of the present invention with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the stapler of a first embodiment according to the present invention;

Figure 2 is a longitudinal sectional view of the stapler shown in Figure 1 ;

Figures 3a and 3b illustrate, in a larger scale, the operational components shown in Figure 1 when the striking plate is at its initial position and fire position, respectively; Figure 4 illustrates the relative movements between the cover plate and the body;

Figure 5 illustrates a stapler of a second embodiment according to the present invention;

Figures 6a, 6b and 6c illustrate a stapler of a third embodiment according to the present invention;

Fig. 7 illustrates a stapler of a fourth embodiment according to the present invention; Figs 8a and 8b illustrate the operational components in Fig. 7 when the striking plate is at its initial position and fire position, respectively;

Fig. 9a schematically and partially illustrates a fifth embodiment of the stapler according to the present invention;

Fig. 9b schematically illustrates the paths of the returning movement of the lugs and tabs in Fig. 9a; and

Fig. 10a - 1Od are partial perspective views showing an embodiment of the actuation mechanism of the stapler at various operational stages according to the present invention. Best Mode of Carrying Out the Invention

As shown in Fig. 1, the stapler 100 of the first embodiment according to the present invention generally comprises a base 101, a body 102 having a front end 102b and a rear end 102a, and a cover plate 103 having a front end 103b and a rear end 103a. The body 102, which basically comprises a staple magazine 125 (most clearly in Figs. 3a and 3b) for accommodating a set of staples or a staple stick 126, is pivotally connected to a pair of upstanding bracket plates 104 fixedly secured on the upper surface 11 1 of the base 101 near a rear end 101a thereof. Similarly, the cover plate 103 is pivotally connected to the bracket plates 104 too. Proper mechanism (not shown) is also provided to prevent the cover plate 103 and the body 102 from undesirably swinging away from the base 101 without a proper force applied by a user. As shown in Fig. 2, a striking plate 123 is conventionally provided in front of the staple magazine 125 for individually dispensing the staples from the staple stick 126 contained in the staple magazine 125 during a stapling operation. Upon actuation of a striker spring 120 during each stapling operation, the striking plate 123 can reciprocally move vertically between an initial position as shown Fig. 3 a and a fire or release position as shown in Fig. 3b.

According to an exemplary embodiment of the present invention, a triggering lever 110 is provided between the base 101 and the body 102, and extends forwardly (i.e., in a direction toward the front ends 101b, 102b) from the upper surface 1 1 1 of the base 101 to an under surface 129 of the body 102. The lower end 10a is preferably fixed to the upper surface 111 of the base 101 , while the upper end 110b freely abuts against the under surface 129 of the body 102. Thus, the triggering lever 110 is inclined to slide forward toward the front ends 101b, 102b of the base 101 and the body along the under surface 129 when front ends 101b, 102b are forced to move closer to each other. Preferably, the triggering lever 1 10 is made of a resilient material, and thus also serves as a raiser element that normally biases the base 101 and the body 102 away from each other by a proper distance, as illustrated in Fig. 2, for accepting a work piece 140, such as a stack of papers, therebetween.

The striker spring 120 is mounted on a lateral shaft 141. An end 120a of the striker spring 120 is secured by a stop plate 124 fixed on the body 102, and another end 120c of the striker spring 120 engages with an opening formed on the striking plate 123 (more clearly shown in Figs. 3a and 3b). The middle or engagement portion 120b of the striker spring 120 engages with the upper end 1 10b of the triggering lever 110 when the body 102 and the base 101 are moved closer to each other, whereby the forward movement of the upper end 1 10a of the triggering lever 1 10 forces the striker spring 120 to deform and rotate clockwise, and the end 120c moves upward, bringing the striking plate 123 to move from the initial position to the fire position, as will be explained in more detail below.

As shown in Figure 3a, before a stapling operation, the striking plate 123 stays in its initial position and fills in the dispensing gap 128. The staple stick 126 is biased toward the striking plate 123 by a biasing spring 127, with a leading staple 126a being pressed against the striking plate 123. At this time, a release bar 132 extending from the cover plate 103 does not touch the triggering lever 110.

During a stapling operation, a pressure is applied on the cover plate 103 to move the body 102 toward the base 101. The upper end 1 10b of the triggering lever 110, which engages with the engagement portion 120b of the striker spring 120, slides forward along the under surface 129 and pushes the striker spring 120 to deform and rotate clockwise around the lateral shaft 141. The free end 120c is forced to move upward, thereby lifting the striking plate 123 to the fire position as shown in Fig. 3 b. At the same time, energy is stored in the deformed striker spring 120. Under biasing force of the spring 127, the staple stick 126 is pushed forward and the leading staple 126a enters the dispensing gap 128 left by the lifted striking plate 123.

When the striking plate 123 reaches the fire position as shown in Fig. 3b, the upper end 1 10b still engages with the engagement position 120b. However, at this point, the release bar 132 has reached the triggering lever 110, because a stop 131 has now slid down a slope 122, as explained later in more detail, permitting the release bar 132 to move downwardly. Thus, upon further pressing the cover plate 103, the release bar 132 will press the triggering lever 110 downwardly to leave and disengage from the engagement portion 120b of the striker spring 120, whereby the striker spring 120 is released to resume its initial shape. Thus, with the energy released from the striker spring 120, the striker spring 120 powerfully drives the striking plate 123 back to its initial position as shown in Fig. 3a, and the striking plate 123 in turn strikes the leading staple 126a in the dispensing gap 128 into the work piece 140. With the appropriately shaped stapling recesses I l ia provided on the upper surface 1 11, the leading staple 126a is bent and stapled to the work piece 140 in a conventional way. The striking plate 123 resumes its initial position and fills in the dispensing gap 128 as shown in Fig. 3a, ready for a next stapling operation. To facilitate returning of the triggering lever 1 10 after the striking spring 120 resumes its initial shape, the engagement portion 120b of the striker spring 120 preferably has a generally round forward portion so that the upper end 110b of the triggering lever 1 10 can easily slide over the engagement portion 120b back to its initial position. However, the backward portion is preferably flat or slightly concave for providing solid engagement with the upper end 110b of the triggering lever 1 10 before the striking plate reaches the fire position. Preferably, the release bar 132 has an inclined lower edge 132a so as to provide a better contact with the triggering lever 1 10.

As mentioned above, before the stapling operation, the release bar 132 does not touch the triggering lever 120, as shown in Fig. 3a. This is realized by a gap provided between the under surface 103d of the cover plate 103 and the upper surface 121 of the body 102. More specifically, a stop 131 is provided depending from the under surface 103d of the cover plate 103 near the front end 103b and rests on an edge portion 121a of the top surface 121 near the front end 102b. Preferably, the edge portion 121b is formed with a forwardly inclined slope 122. The edge portion 121b may be made of a different material from that of the upper surface 121 (as shown), or may simply be a portion of the upper surface.

During the stapling operation, the cover plate 103 moves relative to the body 102, and the stop 131 will leave the edge portion 121a, thus decreasing the gap between the under surface 103d of the cover plate 103 and the upper surface 121 of the body 102, whereby moving the release bar 132 downwardly relative to the body 102 so as to press on the triggering lever 110. The relative movement between the cover plate 103 and the body 102 will be explained with more detail below.

As shown in Figs. 2 and 4, the cover plate 103 is pivotally connected to the bracket plates 104 (which are fixed to the base 101) at a pivotal point 103 c, while the body 102 is pivotally connected to the bracket plate 104 at a pivotal point 102c. As shown in Fig. 5, when both the cover plate 103 and the body 102 are rotated around respective pivotal points 103c and 102c, the rotational radius Rl of the stop 131 is larger than the rotational radius R2 of the edge portion 121a. Thus, when the cover plate 103 and the body 102 rotate together, the stop 131 will gradually slide along the slope 122 and finally leave the edge portion 121a, which decreases the gap between the under surface 103 d of the cover plate 103 and the upper surface 121 of the body 102.

Figure 5 shows a second embodiment which is similar to that shown in Fig. 3a and 3b. In this embodiment, the cover plate 103 is spaced from the upper surface 121 by a compressed spring 133. Before the striking plate 123 reaches its fire position (such as shown in Fig. 3b) during a stapling operation, the compressed spring 133 is strong enough to prevent the cover plate 103 to move closer to the body 102. When the striking plate 123 reaches its fire position, the triggering lever 1 10 still engages with the engagement portion 120b of the striker spring 120, and the body 102 continues to move downward until it rests on the work piece 140. Then, further applying pressure on the cover plate 103 will overcome the force of the compressed spring 133 and move the cover plate 103 downwardly relative to the body 102, whereby the release bar 132 presses on the triggering lever 110 to release the triggering lever 1 10 from engagement with the engagement portion 120b of the striker spring 120. Conceivably, in this embodiment, the pivotal points 102c, 103c of the cover plate 103 and the body 102 (Fig. 2) can be the same or close to each other.

Figures 6a, 6b and 6c illustrate a third embodiment similar to Figs 1 - 5. In this embodiment, the triggering lever 1 10 is formed with a square opening 110c near the upper end 110b. Fig. 6a shows the status before a stapling operation. Fig. 6b shows that the striking plate 123 reaches the fire position during a stapling operation, in which the engagement portion 120b of the striker spring 120 reaches the edge of the opening 1 10c of the triggering lever 1 10. Upon further pressing the body 102 toward the base 101 , the engagement portion 120b of the striker spring 120 will snap back into the opening 1 10c of the triggering lever 1 10 as shown in Fig. 6c, thereby releasing the force that the triggering lever 110 has been applying on the striker spring 120. The striking spring 120 resumes its initial shape and actuates the striking plate 123 to dispense the staple 126b, with the engagement portion 120 staying inside the opening 110c. After the stapling operation, the user may lift the body 102 from the base 101 to help removing the engagement portion 120b of the striker spring 102 from the opening 110c, thus the triggering lever 110 can return to its initial position. In this embodiment, the cover plate 103 and the release bar 132 are not needed, and the force can be applied directly to the upper surface 121 of the body 102 for the stapling operation. Fig. 7 illustrates a fourth embodiment according to the present invention. Unlike the previous embodiments in which the triggering lever 110 moves the striking plate 123 through the striker spring 120, in this embodiment, the triggering lever 1 10 does not directly engage with the striker spring 120, but instead actuates the striking plate 123 by means of an L-shaped transmission element 150 rotatably mounted on a lateral shaft 151. The upper end 110b of the triggering lever 110 abuts against the lower end 150b of the transmission element 150, while the upper end 150a of the transmission element 150 engages with an opening in the striking plate 123. With a proper return spring mechanism (not shown), the transmission element 150 is biased to the position as shown in Fig. 7, where the striking plate 123 rests at its initial position and the upper end 150a engages with the opening in the striking plate 123. Similar to the previous embodiments, the striker spring 120 is mounted on a lateral shaft 141. One end 120a of the striker spring 120 is retained by a stop plate 124, while the other end 120c engages with an aperture formed on the striking plate 123.

Before the stapling operation, as shown in Fig. 8a, the striking plate 123 stays in the initial position and fills in the dispensing gap 128. The staple stick 126 in the staple magazine 125 is biased forward by the spring 127, with a leading staple 126a pressed against the striking plate 123. Similar to the previous embodiments, the triggering lever 1 10 is preferably made of a resilient material and servers as a raiser element to keep the body 102 and the base 101 away from each other by a proper distance for accepting a work piece 140. Before the stapling operation, the upper end 110b abuts the lower end 150b of the transmission element 150, while the upper end 150a of the transmission element 150 engages with the opening on the striking plate 123 under the biasing force of the return spring mechanism (not shown).

During a stapling operation, a pressure is applied on the cover or upper surface 121 of the body 102 so as to move the body 102 toward the base 101. The upper end 1 10b of the triggering lever 1 10 moves forward and forces the L-shaped transmission element 150 to rotate clockwise around the shaft 151 , whereby the upper end 150a moves upward against the force of the return spring mechanism as well as the force of the spring 120, and lifts the striking plate 123 to the fire position as shown in Fig. 8b. At the fire position shown in Fig. 8b, the striking plate 123 leaves the dispensing gap 128, and the leading staple 126a is forced by the spring 127 to enter the dispensing gap 128. The up-going striking plate 123 forces the end 120c of the striker spring 120 to move upward and deforms and energizes the striker spring 120. In the fire position shown in Fig. 8b, the upper end 150a of the transmission element 150 is ready to disengage from the opening of the striking plate 123. Thus, further pressing on the body 102 will further rotate the transmission element 150 to release the upper end 150a from the opening of the striking plate 123. Without the upward force applied by the transmission element 150 on the striking plate 123, the deformed striker spring 120 powerfully drives the striking plate 123 downward back to its initial position as shown in Fig. 8a to dispense the leading staple 126a in the dispending gap 128 to the work piece 140.

After the striking plate 123 resumes its initial position, the force applied on the cover or upper surface 121 of the body 102 may be removed. The resilient triggering lever 110 moves back to its initial position, releasing its engagement with the lower end 150b of the transmission element 150. The transmission element 150 returns to its initial position as shown in Fig. 8a under the biasing force of the return spring mechanism (not shown), and the upper end 150a re¬ engages with the opening of the striking plate. All the components are now ready for next stapling operation again. In a further embodiment of a conventional stapler, the stapler a mainly comprises a magazine 40 for accommodating a staple stick 41, a base 50 for placing a work piece 70 (such as a stack of paper) thereon, and a cover 60 for accepting a pressing force from a user for a stapling operation, as illustrated in Figs. 9a and 9b. During a stapling operation, the striking plate 10 is first lifted from an initial position to a fire or release position (as shown in dashed line), leaving a slot space below into which a single staple is pushed from the staple stick 41 under a biasing force from the compressed spring 42. When the striking plate 10 is driven from the release position back to its initial position, the single staple is driven into the work piece 70 on the base 50 to staple the work piece 70.

As schematically illustrated in Fig. 9a, the actuation mechanism of this embodiment of the present invention mainly comprises a leaf spring 20 for driving the striking plate 10 between the initial position and the release position, and an actuation bar 30 for lifting the leaf spring 20 from a lower position to an upper position (as shown in dashed lines) so as to lift the striking plate 10 from the initial position to the release position. As will be explained in more detail below, when the leaf spring 20 reaches the upper position and therefore the striking plate 10 is brought to the release position, the leaf spring 20 is released from the actuation bar 30, and powerfully drives the striking plate 10 from the release position back to the initial position when the leaf spring 10 returns from the upper position to the lower position. A front end 22 of the leaf spring 20 engages with the striking plate 10 (e.g., by an opening in the striking plate 10) so that the front end 22 of the leaf spring 20 moves together with the striking plate 10, whereby driving the striking plate 10 to move vertically between the initial position and the release position. A back end 23 of the leaf spring 20 is fixed to the magazine 40, for example, on an upper surface 43 of the housing body of the magazine 40. When there is no external force applied to the actuation bar 30, the actuation bar 30 is in an idle position, the leaf spring 20 remains in the lower position, and the striking plate 10 rests in the initial position, as shown by the solid lines. During the stapling operation, the leaf spring 20 is lifted from the lower position to the upper position and brings the striking plate 10 from the initial position to the release position. At the same time, the leaf spring 20 is loaded when it is lifted upwards. In the stapling operation, an external force ("F" in Fig. 9a) is applied to the actuation bar 30, e.g., by pressing on the cover 60. Under the external force, the actuation bar 30 comes into engagement with the leaf spring 20 and lifts the leaf spring 20 from the lower position to the upper position, whereby bringing the striking plate 10 from the initial position to the release position, as described above. In the preferred embodiment illustrated in Fig. 9a, the actuation bar 30 has a rounded L-shaped front end 32. In the idle position, the L-shaped front end 32 is slightly apart from a ramp 33 formed on the upper surface 43 of the magazine 40. When the external force is applied to the actuation bar 30, the front end 32 is pushed forward to abut against the ramp 33 and moves upward along the ramp 33. Alternatively, the front ends 32 of the actuation bar 30 may abut the ram 33 when the actuation bar 30 is in its initial position, as illustrated in Figs. 1Oa-IOd. A pair of lugs 31 are provided on the actuation bar 30 (as best shown in Figs. 1Oa-IOd), which protrude laterally from the length of the actuation bar 30. When the L-shaped front end 32 is pushed forward (i.e., in a direction toward the striking plate 10) by the external force applied to the actuation bar 30, the lugs 31 come into contact with a pair of tabs 21 (best shown in Figs. 1 Oa-I Od). When the L-shaped front end 32 is pushed, under the external force applied to the actuation bar 30, to moves upward along the ramp 33, the lugs 31 push the tabs 21 upward, whereby lifting the leaf spring 20 toward its upper position as shown in dashed lines, and at the same time loading the leaf spring 20. Consequently, the striking plate 10 is lifted by the front end 22 of the leaf spring 20 to the release position against a biasing force from the leaf spring 20, as shown in dashed lines.

Preferably, when the front end 32 moves upward along the ramp 33, the tabs 21 are able to slide backward along an upper surface of the lugs 31. Thus, the upper surface of the lugs 31 function as a ramp for the tabs 21. When the leaf spring 20 reaches the upper position and therefore the striking plate 10 reaches the release position, the tabs 21 reach back edges 31a of lugs 31 and drop from the lugs 31 to disengage themselves from the lugs 31. Under the biasing force loaded in the leaf spring 20, the tabs 21 return to their initial positions (i.e., the lower position shown in solid lines), and the load in the leaf spring 20 is released, which powerfully drives the striking plate 10 from the release position to the initial position where the striking plate 10 strikes a stapler into the work piece 70.

Preferably, a biasing mechanism is provided to the actuation bar 30 so that after the external force applied to the actuation bar 30 is released, the actuation bar 30 can automatically return to its initial position (as shown in solid lines) under a biasing force. In the embodiment shown in Fig. 9a, the biasing force is provided by a resilient lever 34 which connects the actuation bar 30 at a back end 35 to the upper surface 43 of the magazine 40. When the actuation bar 30 moves forward under the external force applied to it through the cover 60, the resilient lever 34 is brought to bend forward and the biasing force is loaded in the resilient lever 34. When the external force is removed, the load built in the resilient lever 34 is released, and the resilient lever 34 returns to its initial position and pulls the actuation bar 30 back to its initial position as well.

It is important that the lugs 31 of the actuation bar 30 are not obstructed by the tabs 21 (which have returned to their initial positions) on their way of returning to their initial positions after the external force is removed. As illustrated in Fig. 9b, after the external force is removed, the lugs 31 are pulled backward by the biasing force from the resilient lever 34 and move along path "B" which is not obstructed by the tabs 21 already returned to their initial positions from the lugs 31 along the path "A".

Preferably, the lugs 31 may assume an angle (e.g., 30 degree) from a man flat body of the actuation bar 30, as illustrated in Figs. 10a- 1Od, which show the actuation mechanism in various operational stages.

Fig. 10a shows the actuation mechanism in a position before or after a stapling operation, in which the actuation bar 30 rests in its initial idle position because there is no external force applied on it. The lugs 31 on the actuation bar 30 are not engaged with the tabs 21 of the leaf spring 20. The striking plate 10 rests in the initial position, and the leaf spring 20 is in the lower position.

During the loading stage of the stapling operation, when the front end 32 of the actuation bar 30 is pushed forward by an external force, the lugs 31 come into engagement with the tabs 31 and push the tabs 21 upward when the front end 32 moves upward along the ramp 33, until the leaf spring 20 reaches the upper position where the striking plate 10 is lifted to the release position, as shown in Figs. 1 Ob and 1 Oc in different angels of view. In this stage, the tabs 21 slide backward along the upper surface of the lugs 31 toward the back edges 31a of the lugs 31. After the leaf spring 20 reaches the upper position and the striking plate 10 reaches the release position as shown in Figs. 10b and 10c, when the L-shaped front end 32 further moves upwards along the ramp 33, the tabs 21 of the leaf spring 10 drops from the back edges 31a of the lugs 31 to disengage itself from the actuation bar 30. Under the biasing force built in the leaf spring 20 during the loading stage, the leaf spring 20 snaps back to the lower position, and at the same time powerfully drives the striking plate 10 back to the initial position for stapling the work piece 70, as shown in Fig. 1Od. After the stapling operation is finished, the external force is removed from the actuation bar 30. Under the biasing force from the resilient lever 34 (see Fig. 9a), the actuation bar 30 returns to its initial position, as shown in Fig. 10a, and ready for a next stapling operation. Although the above has described several preferred embodiments, it is appreciated that numerous adaptations, changes, variations and modifications are possible to a person skilled in the art without departing the spirit of the present invention. For example, For example, the striker spring 120 can be advantageously constructed with dual legs for higher strength.

Alternatively, the striker spring 120 can be a leaf spring. Moreover, the triggering lever 110 may be arranged inside the body 102, such as between the cover plate 103 and the body 102, and not connected to the base 101. The flat shaped tabs 21 may be implemented as a pair of laterally protruding rods mounted on the leaf spring 20. The resilient lever 34 can be replaced by any proper biasing mechanism for returning the actuation bar 30 toward its initial position. For example, the actuation bar 30 can also be a leaf spring with the back end 35 connected to the cover 60. Therefore, the scope of the present invention is solely intended to be defined by the accompanying claims.

Claims

We claim:

1. A stapling apparatus, comprising: a base member having a first end and a second end; a magazine member for accommodating a set of staples therein, said magazine member having a first end and a second end and is pivotally connected with said base member at said first ends of said two members; a striking plate for individually dispensing said staples upon actuation by a striker spring; and a triggering mechanism for triggering said actuation of said striker spring; wherein said triggering mechanism comprises a triggering lever arranged such that said triggering lever triggers said actuation of said striker spring when said seconds ends of said two members are moved towards each other.

2. The stapling apparatus of claim 1 , wherein said triggering lever has a lower end secured to an upper surface of said base member.

3. The stapling apparatus of claim 2, wherein said triggering lever has an upper end freely abutting against a bottom surface of said staple magazine.

4. The stapling apparatus of claim 3, wherein said triggering lever is made of a resilient material and normally biases said second ends of said base member and said magazine member away from each other by a distance for accepting a work piece.

5. The stapling apparatus of claim 4, wherein said striker spring has a first end portion engaged with an opening formed on said striking plate for moving said striking plate between a first position and a second position.

6. The stapling apparatus of claim 5, wherein said triggering lever is arranged such that, when said magazine member and said base member are moved toward each other, said upper end of said lever engages with said striker spring to force said striker spring to deform whereby said striker spring brings said striking plate from said first position to said second position. ,

7. The stapling apparatus of claim 6, further comprising a release mechanism for releasing said engagement between said trigger lever and said striker spring when said striking plate reaches said second position whereby said striker spring resumes its initial form and drives said striking plate back to said first position for dispensing a leading one of said staples.

8. The stapling apparatus of claim 7, wherein said release mechanism comprises a release bar for pushing push said trigger lever downwardly when said striking plate reaches said second position, so as to disengage said trigger lever from said striker spring.

9. The stapling apparatus of claim 8, wherein said release mechanism further comprises a cover member provided above said magazine member, and said release bar depends from an undersurface of said cover member.

10. The stapling apparatus of claim 9, wherein said cover member comprises a first end pivotally connected to said first end of said base member and a free second end.

11. The stapling apparatus of claim 10, wherein said cover member is spaced from an upper surface of said magazine member, whereby preventing said release bar from reaching said trigger lever before said striking plate reaches said second position.

12. The stapling apparatus of claim 11, wherein said cover member and said magazine member are spaced by means of a stop, which is formed on said undersurface of said cover member near said second end thereof, and rests on an edge portion formed on said upper surface of said magazine member at said first end thereof.

13. The stapling apparatus of claim 12, wherein said cover member and said magazine member are pivotally connected with said first end of said base member in a way that said stop moves beyond said edge portion when said cover member and said magazine members are moved together toward said base member during a stapling operation, whereby said space between said cover member and said magazine member is diminished, and said release bar presses on said trigger lever.

14. The stapling apparatus of claim 13, wherein said edge portion on said upper surface of said magazine member terminates with a slope inclined forwardly.

15. The stapling apparatus of claim 14, wherein said stop is adapted to slide along said slope so as to gradually diminish said space between said cover member and said magazine member when said cover member and said magazine members are moved together toward said base member during a stapling operation.

16. A stapling apparatus, comprising: a base and a staple magazine for accommodating a set of staples therein, said base and said magazine each having a first end and second end, and being pivotally connected to each other at first ends and normally biased away from each other by a distance at second ends; a striking plate for individually dispensing said staples upon actuation by a striker spring, said striking plate being reciprocally movable between a first position and a second position; and a triggering lever arranged such that when said second ends of said base and said magazine are forced to move toward to each other, said triggering lever forces said striking plate to move from said first position to said second position and forces said spring to deform, and when said striking plate reaches said second position, said triggering lever releases said striking plate to be driven by said striking plate back to said first position for dispensing a leading one of said staples.

17. The stapling apparatus of claim 16, wherein said triggering lever is made of a resilient material having a lower end secured on said base and a free upper end abutting against said magazine whereby normally keeping a distance between said base and said magazine.

18. The stapling apparatus of claim 17, wherein said triggering level extends from said base to said magazine in an direction toward said second ends, whereby said upper end is adapted to move in a direction toward said second end relative to an undersurface of said magazine when said magazine and said base are toward to each other during a stapling operation.

19. A stapling apparatus of claim 18, wherein said triggering lever cooperates with a transmission mechanism to force said striking pate to move from said first position to said second position.

20. The stapling apparatus of claim 19, wherein said transmission mechanism comprises an driving shaft for engaging with an opening provided on said striking plate.

21. A stapler comprising: a base portion; a body portion having a housing for accommodating a staple stick therein; a plunger, actuated by a striker spring, for dispensing a leading staple of said staple stick to a work piece placed between said base portion and said body portion; and a trigger for forcing said striker spring to deform when said base portion and said body portion are squeezed toward each other until a point where said striker spring is released to resume its initial form, thereby actuating said plunger to dispense said leading staple.

22. The stapler of claim 21 , wherein said trigger is a resilient lever having a first end secured to said base and a second end freely abutting against an undersurface of said body portion, whereby normally biasing said base portion and said body portion away from each other by a distance.

23. The stapler of claim 21, wherein said trigger engages with said striker spring and drives said plunger from an initial position to a release position through said striker spring.

24. The stapler of claim 21, wherein said trigger engages with said plunger and forces said striker spring to deform through driving said plunger to move from an initial position to a release position.

25. A stapler comprising: a striking plate for dispensing a staple from a staple magazine; a leaf spring engaged with said striking plate for driving said striking plate; and an actuator for lifting said leaf spring, in a plane, from a first position to a second position whereby said leaf spring lifts said striking plate from an initial position to a release position, wherein said leaf spring is adapted to slide, in said plane, on said actuator while being lifted by said actuator, until said leaf spring is lifted to said second position in which said leaf spring is released from said actuator to drive said striking plate from said release position towards said initial position.

26. The stapler of claim 25, wherein said actuator comprises a first end portion adapted to move upwards when a force is applied to said actuator, whereby lifting said leaf spring.

27. The stapler of claim 26, wherein said first end portion comprises a raising portion adapted to lift said leaf spring when said force is applied to said actuator.

28. The stapler of claim 27, wherein said first end portion further comprises a front portion adapted to move on a guiding ram when said force is applied to said actuator.

29. The stapler of claim 28, wherein said raising portion of said actuator is adapted to push up a tab provided on said leaf spring and therefore to lift said leaf spring when said force is applied to said actuator.

30. The stapler of claim 29, wherein said tab and said raising portion is configured such that when said leaf spring is lifted to said second position, said tab disengages itself from said raising portion so as to release said leaf spring from said actuator.

31. The stapler of claim 30, wherein said tab is adapted to slide on an upper surface of said raising portion when said front portion moves on said guiding ram.

32. The stapler of claim 31, wherein said tab and said raising portion are configured such that when said front portion moves on said guiding ram, said raising portion moves upwards and said tab slides backwards on said upper surface of said raising portion.

33. The stapler of claim 32, wherein said raising portion is a lug protruded laterally from said actuator, and said tab of said leaf spring is adapted to disengage itself from said lug after said tab slides to an edge of said lug.

34. The stapler of claim 26, wherein said actuator further comprises a biasing mechanism for returning said actuator to an initial position after said applied force is removed.

35. The stapler of claim 34, wherein said biasing mechanism is a resilient lever connecting a second end of said actuator to a body of said magazine.

36. The stapler of claim 35, wherein said actuator further comprises a second end portion, and said force is applied to said second end portion.

37. The stapler of claim 36, wherein said force is applied to said actuator by pressing on a cover of said stapler pivotally connected to said magazine.

38. The stapler of claim 37, further comprising a base plate pivotally connected to said magazine.

39. The stapler of claim 28 wherein said guiding ram is provided on said magazine.

40. A stapler comprising: a striking plate for individually dispensing staples from a staple magazine; a leaf spring adapted to drive said striking plate from an initial position to a release position when it said leaf spring is being lifted, in a plane, from a lower position to an upper position, and adapted to drive said striking plate from said release position back to said initial position when it said leaf spring returns from said upper position to said lower position; and an actuator adapted to lift said leaf spring from said lower position to said upper position; wherein said leaf spring is adapted to slide, in said plane, on said actuator while being lifted by said actuator until said leaf spring is lifted to said upper position in which said leaf spring is released from said actuator.

41. (currently amended) The stapler of claim 40, wherein said actuator comprises a lateral lug for engaging with a tab provided on said leaf spring so as to lift said leaf spring when a force is applied to said actuator.

42. The stapler of claim 41 , wherein said actuator further comprises a front end movable on a guiding ram when said force is applied.

43. The stapler of claim 42, wherein said tab and said lateral lug are configured such that said tab disengages itself from said lug when said leaf spring reaches said upper position.

44. The stapler of claim 43, wherein said tab is adapted to slide on an upper surface of said lateral lug when said front end moves on said guiding ram.

45. The stapler of claim 44, wherein said actuator is connected to said magazine through a resilient lever so as to return to its initial position when said applied force is removed.

46. An actuation mechanism for driving a striking plate in a spring actuated stapler, comprising: a leaf spring engaged with said striking plate so as to drive said striking plate between an initial position and a release position; and an actuator for lifting said leaf spring, in a plane, from a lower position against a biasing force from said leaf spring to an upper position so that said leaf spring drives said striking plate from said initial position to said release position, wherein said leaf spring is adapted to slide, in said plane, on said actuator while being lifted by said actuator, until said leaf spring is lifted to said upper position in which said leaf spring is released from said actuator so as to return to said lower position, whereby driving said striking plate from said release position to said initial position.

47. The actuation mechanism of claim 46, wherein said actuator comprises a laterally protruding lug adapted to push upwards a tab provided on said leaf spring so as to lift said leaf spring when an external force is applied to said actuator.

48. The actuation mechanism of claim 47, wherein said tab is adapted to disengage itself from said lug when said leaf spring reaches said upper position so as to release said leaf spring from said actuator.

49. The actuation mechanism of claim 48, wherein said actuator further comprises a front end portion adapted to move on a guiding ram when said external force is applied to said actuator.

50. The actuation mechanism of claim 49, wherein said tab of said leaf spring is adapted to slide on an upper surface of said lug when said front end portion moves on said guiding ram.

51. The actuation mechanism of claim 50, wherein said tab and lug are configured such that said tab disengages itself from said lug when said tab arrives an edge of said lug so as to release said leaf spring from said actuator.

52. The actuation mechanism of claim 51 , wherein said actuator is connected to a body of a staple magazine through a resilient lever so as to return to an initial position when said external force applied to said actuator is released.