Hand-held staple gun having a safety device

[0001] 1. Field of the Invention

[0002] The present invention relates to staple guns having a safety device and, more particularly, to a hand-held staple gun having a safe actuation mechanism.

[0003] 2. Description of Related Art

[0004] Staple guns are powerful hand-held machine used to drive metal staples into, for instance, solid wood. Aside from the staple guns driven by electricity or compressed air, the staple guns of hand-powered (muscle power) models always have a spring means for storing mechanical energy and delivering it as a sharp powerful blow. As such, providing auxiliary devices attached to the staple guns for better accomplishing work, and particularly for safety, becomes important and necessary. Among others, examples may be given to U.S. Pat. No. 6,729,525, issued to Chou, for a staple gun having an improved structure for a two-dimensional positioning purpose; and U.S. Pat. No. 6,082,604, issued to Dennis, for a staple gun having an alignment device that prevents the staple gun from firing unless it is properly aligned with respect to an object to be fastened.

[0005] It is therefore an object of the present invention to provide a hand-held staple gun having a safety device, so that unintentional firing of the staple gun may be prevented and a safe use of the staple gun maintained.

[0006] It is a further object of the present invention to provide a hand-held staple gun having a safety device, wherein the safety device relates to a safe actuation mechanism including, among others, an actuation control rod which allows a driver of the staple gun to fire staples only when a user attempts to use the staple gun and thus presses on the actuation control rod intentionally.

[0007] According to the present invention, the hand-held staple gun comprises a housing, a driver, a spring means, a handle, and a safe actuation mechanism. The safe actuation mechanism includes a swing means, a link, and an actuation control rod. The swing means is pivotally secured to the housing and the link is pivotally connected with the swing means. When the staple gun is not in use, the link cannot engage the driver even if the handle is pressed downward, and when the staple gun is in use, the actuation control rod is pressed upward into the housing, so that the actuation control rod pushes the swing means, making the link engage the driver, where the driver, being biased by the spring means, is moved upward when the handle is pressed down, and when the handle is pressed down continuously, the link releases abruptly from the driver, making the driver rushes downward so as to drive the staples out of the staple gun, through the help of the elasticity force of the spring means.

[0008] Other objects, advantages, and novel features of the present invention will become more apparent from the following detailed descriptions when taken in conjunction with the accompanying drawings.

[0034] As shown in FIGS. 1, 2 and 3, the hand-held staple gun according to the first embodiment of the present invention comprises a housing 10, a driver 20, a spring means 30, a handle 40, and a safe actuation mechanism A.

[0035] The housing 10 includes a left side 101, a right side 102, and a front side 103. The housing 10 defines an internal space 11, where the internal space 11 includes an accommodation chamber 111. The spring means 30, being a compression spring, is positioned, in a compressed state, in the accommodation chamber 111, whereas the driver 20 and the safe actuation mechanism A are received in the internal space 11.

[0036] The driver 20 is formed with an opening 21 and a support 24 on which the spring means 30 is seated, and an impact portion 23 formed at the lower part of the driver 20. The spring means 30 provides the driver 20 a driving force so as to fire staples (not shown) at the impact portion 23. To reduce the shock and noise produced when firing of the staples, a plate 112, to which a buffer pad 113 is adhered, is firmly secured to the housing 10 in the accommodation chamber 111. The handle 40 is, at its front end, pivotally secured to the housing 10 with a pin 403.

[0037] The safe actuation mechanism A includes a swing means 42, a link 70, and an actuation control rod 50. The swing means 42 is pivotally secured to the housing 10 via a pin 423, and the link 70 is pivotally connected with a second end 422 of the swing means 42 with a pin 73, with a torsion spring 74 provided around the pin 73 where one end of the torsion spring 74 biases against the link 70 and another end of the torsion spring 74 against the swing means 42. The link 70 has a first end 71 positioning besides the opening 21 of the driver 20, and has a second end 72 mounted with a roller 721 so as to facilitate interaction of the handle 40 and the link 70 when the underside of the handle 40 presses against the second end 72 of the link 70. The actuation control rod 50 stretches, at a first end 51, out of the bottom of the housing 10, whereas a second end 52 of the actuation control rod 50 touches a first end 421 of the swing means 42 such that the actuation control rod 50 is biased by the elastic force of the torsion spring 74. The driver 20 is arranged such that it is spaced apart and paralleled with the actuation control rod 50.

[0038] When the staple gun according to the first embodiment of the present invention is in use, the first end 71 of the link 70 cannot engage the driver 20 at the opening 21 even if the handle 40 is pressed down. As shown in FIG 4, when the user intends to operate the staple gun, the first end 51 of the actuation control rod 50 is pressed and moves upward into the housing 10, so that the second end 52 of the actuation control rod 50 pushes the first end 421 of the swing means 42, making the first end 71 of the link 70 overcome the torsion spring 74 and move rightward and thus engage the driver 20 at the opening 21.

[0039] As shown in FIG. 5, when the user presses down the handle 40 so as to move upward the driver 20 and that the support 24 of the driver 20 presses against the spring means 30. When the handle 40 is pressed down continuously, the first end 71 of the link 70 releases abruptly from the opening 21 of the driver 20, making the driver 20 rush downward so as to drive staples out of the staple gun, through the help of the elasticity force of the spring means 30.

[0040] Referring to FIGS. 7 to 10, the second embodiment of the present invention, where a safe actuation mechanism B is similar to the safe actuation mechanism A of the first embodiment in structure and function, except for a different spring means 30, to be exact a torsion spring. The spring means 30 has a first end 31 pressing against the support 24 of the driver 20. A bottom plate 112 is firmly secured to the housing 10 and is provided underneath the support 24 of the driver 20, where a buffer pad 113 is interposed between the bottom plate 112 and the support 24.

[0041] Further referring to FIGS. 11 to 14, the third embodiment of the present invention, where a safe actuation mechanism C is similar to the safe actuation mechanism A of the first embodiment in structure and function, except for a different spring means 30, a leaf spring. The spring means 30 has a first end 32 affixed on the driver 20 and a second end 33 secured to the housing 10. Also, for the purpose of reducing the shock and noise produced, a bottom plate 112 is firmly secured to the housing 10 and is provided underneath the spring means 30, where a buffer pad 113 is interposed between the bottom plate 112 and the spring means 30.

[0042] A fourth embodiment of the present invention, as shown in FIGS. 15 to 17, discloses a hand-held staple gun having a similar inventive concept and function with those of the embodiments above mentioned, though there are differences in terms of structure.

[0043] The hand-held staple gun according to the fourth embodiment of the present invention comprises a housing 10, a driver 20, a spring means 30, a handle 40, and a safe actuation mechanism D. The housing 10 includes a left side 101, a right side 102, a first chute 12 having an outlet 121, and a second chute 14 having an outlet 141, where the left side 101 and the right side 102 define an internal space 11. The driver 20 is formed with an opening 21, an engaging hole 22, and an impact portion 23 at the lower part of the driver 20. The driver 20 is movably received in the first chute 12, with the impact portion 23 extending outward from the outlet 121. The spring means 30 has a first end 31 and a second end 32, where the first end 31 is received and fixed in a recess 13 of the housing 10 and the second end 32 is received in the engaging hole 22 of the driver 20.

[0044] The safe actuation mechanism D includes a swing means 42, a hook 41, and an actuation control rod 50. The actuation control rod 50 is movably disposed in the second chute 14. The swing means 42 is pivotally secured to the housing 10 via a pin 15, and has a first end 421 and a second end 422, with a torsion spring 43 coaxially fixed, on the housing 10, with the swing means 42 and provided around the pin 15, where one end of the torsion spring 43 biases against the housing 10 and another end against the handle 40. The handle 40 is pivotally secured to the swing means 42 via a pin 45 at the second end 422. The hook 41 is fixed to the handle 40 via a pin 44 and has a front end adjacent to the opening 21 of the driver 20. The actuation control rod 50 stretches downward, at a first end 51, and out of the outlet 141 of the second chute 141, whereas a second end 52 of the actuation control rod 50 touches the first end 421 of the swing means 42 such that the actuation control rod 50 is biased by the elastic force of the torsion spring 43. The first end 51 of the actuation control rod 50 is sleeved with a cap 53.

[0045] As shown in FIGS. 18 to 20, when the first end 51 of the actuation control rod 50 is pressed and retracts into the second chute 14, the second end 52 of the actuation control rod 50 pushes upward the first end 421 of the swing means 42, so that the second end 422 of the swing means 42 rotates and pulls the handle 40 to advance a small distance, making the hook 41 engage the driver 20 at the opening 21. When the handle 40 is pressed down so as to move upward the driver 20 and that the support 24 of the driver 20 presses against the spring means 30. When the handle 40 is pressed down continuously, the handle 40, through the hook 41 into the opening 21 of the driver 20, raises the driver 20, and deforms the spring means 30, and then releases from the opening 21 abruptly, making the driver 20 rushes downward so as to drive staples out of the staple gun, with the help of the elastic force of the spring means 30.

[0046] Further, as shown in FIGS. 21 to 23, a hand-held staple gun having a similar inventive concept and function with those of the fourth embodiment shown in FIGS. 15 to 20 (but without the swing means 42), according to the fifth embodiment of the present invention, is also disclosed. A handle 40 is pivotally secured to a housing 10 via a pin 15 fixed on the housing 10, with a torsion spring 43 coaxially fixed, on the housing 10, with the handle 40 and sleeved on the pin 15, where one end of the torsion spring 43 presses on the housing 10 and another end on the handle 40. An actuation control rod 50 of a safe actuation mechanism E is formed of an L shape, including a vertical end 51, sleeved with a cap 53, movably disposed in and stretching downward out of an outlet 141 of a second chute 14 of the housing 10, and a horizontal end 52 abutting on a rear end of a hook 41, where the hook 41 is pivotally secured to the handle 40 via a pin 44 such that the actuation control rod 50 is biased by the elastic force of the torsion spring 43. When the horizontal end 52 of the actuation control rod 50 pushes the rear end of and rotate the hook 41 making the front end of the hook 41 move into an opening 21 of a driver 20 (see FIG. 24), where the driver 20 is movably received in a first chute 12 of the housing 10. By pressing down of the handle 40, the driver 20 is raised (FIG. 25), and a spring means 30 biasing on the driver 20 is deformed. The spring means 30 has a first end 31 received and fixed in a recess 13 of the housing 10 and a second end 32 received in an engaging hole 22 of the driver 20. Then the front end of the hook 41 releases abruptly from the opening 21 of the driver 20 and makes the driver 20 rushing downward, with an impact portion 23 at the lower part of the driver 20 driving staples out of the staple gun by the elastic force of the spring means 30 (not shown).

[0047] Although the present invention has been explained in relation to its preferred embodiments, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the invention as hereinafter claimed.