|Publication number||USRE42987 E1|
|Application number||US 12/201,413|
|Publication date||Dec 6, 2011|
|Filing date||Aug 29, 2008|
|Priority date||May 23, 2000|
|Publication number||12201413, 201413, US RE42987 E1, US RE42987E1, US-E1-RE42987, USRE42987 E1, USRE42987E1|
|Original Assignee||Hitachi Koki Co., Ltd.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (32), Classifications (6), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This is a reissue of U.S. Pat. No. 6,820,788, which is a continuation of application Ser. No. 10/119,721 filed Apr. 11, 2002 now U.S. Pat. No. 6,641,018 which is a continuation of application Ser. No. 09/861,546 filed May 22, 2001; now U.S. Pat. No. 6,394,332; the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to a nail gun that drives a nail through, for example, the hole of a connection clasp and to a nail gun that can accurately drive nails into a desired drive position.
2. Description of the Related Art
A variety of different types of clasp fixing nail guns have been proposed. U.S. Pat. No. 5,193,730 discloses a nail gun that separates nails one at a time from a nail band and supplies the nail to a nail injection hole of the nosepiece. The nail tip is protruded from the end of the nosepiece before the nail gun drives the nail.
The nail gun further has a safety mechanism with a work-piece contact member, an intermediate lever, and an operation lever. The work-piece contact member extends from the nose of the nail gun to the base of the intermediate lever. When the trigger of the nail gun is pressed, the operation lever moves toward or away from an activation plunger, depending on the position of the work-piece contact member and the intermediate lever. That is, the work-piece contact member is raised into its lowermost position as long as the nose of the nail gun is not pressed against a work piece. If the trigger is pressed at this time, the intermediate lever pivots greatly and guides movement of the operation lever away from the activation plunger. On the other hand, when the nose of the nail gun is pressed against a work piece, the contact member is raised into its upper position. If the trigger is pulled at this time, pivoting movement of the intermediate lever is restricted so that the operation lever moves into contact with the activation plunger, thereby setting off a nail driving operation. In other words, the safety mechanism prevents the nail gun from firing when no work piece is present by changing the pivot path of the operation lever.
It is conceivable to lengthen the stroke of the work-piece contact member, that is, the distance that the work-piece contact member can move, by increasing the length of the intermediate lever. However, the intermediate lever can only be lengthened within the movement range of the trigger. Therefore, it is difficult to lengthen the stroke of the work-piece contact member. As a result, the lower end of the work-piece contact member must always be positioned fairly near the nail ejection opening, even when the work-piece contact member is at its upper dead center. This makes it difficult to see the nail tip so that it is difficult to position the nail at the precise position where it is to be driven into the work piece.
Also, the intermediate lever and the operation lever are provided in a narrow space above the trigger and operate in a fairly complicated manner against urging force of springs. A slight error in component or position dimensions, abrasion caused by friction, or dust, dirt, and the like clinging to components could easily become the cause of misfires. As a result, reliability of the nail gun suffers.
It is an objective of the present invention to overcome the above-described problems and provide a nail gun that more easily allows visual confirmation of the nail tip location and that uses a simpler configuration, which improves reliability by helping prevent the danger of misfires.
In order to achieve the above-described objective, a nail gun according to the present invention includes a body; a nail ejection portion connected to the body and having a tip formed with a nail ejection hole; a magazine connected to the nail ejection portion, the magazine feeding nails one at a time to the ejection portion; a blade supported in the body capable of reciprocal movement in opposing first and second directions and, when activated, driven in the second direction to the nail ejection portion to strike a nail in the nail ejection portion and to eject the nail through the nail ejection hole; an activation switch having a protruding plunger, the activating switch activating the blade when the plunger is pressed inward; a trigger having a trigger pivot end and a trigger free end, the trigger being supported pivotably on the body at the trigger pivot end; a trigger arm positioned within the trigger, the trigger arm having a trigger-arm pivot end, a central portion, and a trigger-arm free end, the trigger-arm pivot end being pivotably disposed at a position between the plunger and the trigger free end, the central portion being disposed at a position adjacent to the plunger; a safety portion having a first-side end disposed in contact with the trigger-arm free end and a second-side end positioned near the nail ejection hole, the safety portion being supported capable of reciprocal movement in the first and second directions between an upper dead center and a lower dead center; and urging means for urging the safety portion into the upper dead center; wherein when the trigger is pivoted on the trigger pivot end, pivoting movement of the trigger moves the trigger-arm pivot end to press the central portion of the trigger arm into contact with the plunger and, with the plunger serving as a fulcrum, to press the trigger-arm free end in the second direction against the first-side end of the safety portion.
With this configuration, a long stroke can be achieved for the safety portion. Therefore, the lower end of the safety portion can be separated from the nail tip in the initial condition, so that whether the nail tip is properly set in the clasp hole can be visually confirmed with ease. That is, the position where nails will be driven into the work piece can be accurately set.
Also, only the trigger arm is provided within the trigger and the safety portion is configured from only the upper safety portion and the lower safety portion. Operations are more reliable because the configuration is so simple.
If movement of the safety portion in the second direction is obstructed when the trigger is pivoted on the trigger pivot end, then the first-side end of the safety portion contacted by the trigger-arm free end serves as a fulcrum around which the trigger arm pivots with movement of the trigger, whereupon the central portion presses the plunger inward so that the activation switch activates the blade.
As a result, a nail driving operation can be reliably performed.
The above and other objects, features and advantages of the invention will become more apparent from reading the following description of the embodiments taken in connection with the accompanying drawings in which:
Next, a nail gun according to a first embodiment of the present invention will be provided while referring to
As shown in
The nail ejection portion 5 is formed at its lower end with a nail ejection hole 5a. The tip 4c of the lead nail 4 within the nail ejection portion 5 protrudes downward out of the nail ejection hole 5a, so that the position of the nail tip 4c can be visually confirmed with ease.
The drive portion 8 houses a blade 7. The blade 7 is capable of reciprocal movement in the drive portion 8 to drive nails supplied to the nail ejection portion 5 out from the ejection hole 5a.
The nail gun 1 also includes a handle 9 and an activation switch 10. The handle 9 is held by the user to support the nail gun 1. The activation switch 10 is for controlling a nail driving operation of the nail gun 1. As shown in
As shown in
The safety portion 12 is supported capable of reciprocal movement, in parallel with the reciprocal movement direction of the blade 7, between upper and lower dead centers as guided by a nose 13, which configures the nail ejection portion 5. The safety portion 12 is configured from an upper safety portion 20, a cam member 21, and a lower safety portion 22.
The upper safety portion 20 has a substantial reversed L-shape, and includes the upper end 12a, a vertical section 20c, and a horizontal section 20d. The upper end 12a is disposed in contact with the underside of the free end 19aof the trigger arm 19. A spring 15 is disposed beneath the horizontal section 20d for constantly urging the safety portion 12 toward its upper dead center.
The lower safety portion 22 is supported capable of reciprocal movement in parallel with the reciprocal movement direction of the blade 7, as guided by pins 23, 24 provided in the nose 13. The lower safety portion 22 includes a lower end 12b and an engagement recess portion 22a. The lower end 12b is located near the ejection opening 5a of the nail ejection portion 5. When the safety portion 12 is in its upper dead center following the urging of the spring 15, the lower end 12b is retracted above the nail tip 4c as shown in
The cam member 21 is pivotably supported on a shaft 20a provided to a lower portion of the upper safety portion 20. As shown in
Next, an explanation will be provided for operation of the nail gun 1. In this example, the nail gun 1 is used to fix in place a connection clasp 2 shown in
Next, the user pulls the trigger 11 of the nail gun 1. When the user pulls the trigger 11, the trigger 11 pivots centered on the pivot shaft 16 toward the activation switch 10, that is, from the orientation shown in
The above explanation is for the situation wherein the trigger 11 is pulled after the nail tip 4c protruding from the nail ejection hole 5a was set in the clasp hole 2a. Next, with reference to
In the same manner as described above, when the trigger 11 is pulled in this case, the support portion 18 of the trigger arm 19 moves so that the central portion of the trigger arm 19 abuts against the tip of the plunger 17. Accordingly, the tip of the plunger 17 functions as a fulcrum so that force from the support portion 18 presses the other tip 19a of the trigger arm 19 down against the upper end 12a. However, because there is no work piece to prevent downward movement of the safety portion 12 in this case, the safety portion 12 moves from its upper dead center to its lower dead center against the urging force of the spring 15. The plunger 17 remains positioned at its lower dead center so the activation switch 10 does not turn ON.
As the safety portion 12 moves from its upper dead center to its lower dead center, the cam member 21 moves downward with the upper safety portion 20. As shown in
According to the present embodiment, no other components besides the trigger arm 19 are provided within the trigger 11 and supported pivotably on the trigger 11. Moreover, when the safety portion 12 can move into its lower dead center without obstruction, the plunger 17 serves as a fulcrum when the other tip 19a of the trigger arm 19 presses the upper safety portion 12a down toward its lower dead center. With this configuration the safety portion 12 can have a long stroke, that is, the safety portion 12 moves a long distance from its upper dead center into its lower dead center. Therefore, the lower end 12b of the safety portion 12 can be raised up further above the nail tip 4c, thereby making it easier to visually confirm the position of the nail tip 4c so that the nail will be driven into the work piece with greater positional accuracy.
Also, because the trigger arm 19 pivots with the tip of the plunger 17 serving as a fulcrum, the force at which the safety portion 12 can be pressed downward can be increased. As a result, the following effects can be achieved. It will be possible to move the safety portions 20, 22 downward, even if the safety portions 20, 22 become difficult to move downward because dirt and the like cling to the safety portions 20, 22, the cam member 21, or other components. This enhances reliability of the nail gun. Also, the safety portions 20, 22 can be reliably lowered, even if the load on the spring 15, which is for supporting the safety portions 20, 22 in the upper dead center, is increased because the weight of the safety portions 20, 22 is increased for some reason, for example to increase the strength of, or to lengthen, the safety portions 20, 22.
Next, a second embodiment will be explained while referring to
When the safety portion 120 is in its upper dead center as shown in
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US4629106 *||May 29, 1985||Dec 16, 1986||Signode Corporation||Actuating means for fastener driving tool|
|US5193730 *||May 27, 1992||Mar 16, 1993||Max Co., Ltd.||Pneumatic nailing machine|
|US5238167 *||Oct 9, 1992||Aug 24, 1993||Illinois Tool Works Inc.||Positioning mechanism for powered fastener-driving tool|
|US5452835 *||Mar 31, 1995||Sep 26, 1995||Illinois Tool Works Inc.||Positioning mechanism for powered fastener-driving tool|
|US5551621 *||May 24, 1995||Sep 3, 1996||Stanley-Bostitch, Inc.||Convertible contact/sequential trip trigger with double actuation prevention structure|
|US5579975 *||Apr 19, 1995||Dec 3, 1996||Senco Products, Inc.||Fastener driving tool for locating a pre-existing through hole in a workpiece and driving a fastener therethrough|
|US5662257 *||Mar 10, 1995||Sep 2, 1997||Makita Corporation||Nailing machine|
|US5692663 *||Jul 11, 1996||Dec 2, 1997||Testo Industry Corp.||Trigger structure|
|US5803338 *||Nov 26, 1996||Sep 8, 1998||Senco Products, Inc.||Fastener driving tool for locating a pre-existing hole in a first workpiece and driving a fastener therethrough into a second workpiece|
|US5836501 *||Jun 23, 1997||Nov 17, 1998||Basso Industry Corp.||Safety trigger mechanism for stapler|
|US5862969 *||Sep 17, 1997||Jan 26, 1999||De Poan Pneumatic Corporation||Safety trigger for nailer|
|US6059161 *||Aug 19, 1999||May 9, 2000||Nailermate Enterprise Corporation||Assembly of a power stapler|
|US6116488 *||Feb 23, 2000||Sep 12, 2000||Lee; Yun-Chung||Trigger switching structure of contact/full sequential actuation fastening tool|
|US6199739 *||Aug 10, 1999||Mar 13, 2001||Makita Corporation||Nail guns having means for preventing the nail driving operation|
|US6205894 *||Jun 24, 1999||Mar 27, 2001||Max Co., Ltd.||Automatic stop device for screw striking machine|
|US6371348 *||Jun 23, 2000||Apr 16, 2002||Stanley Fastening Systems, Lp||Fastener driving device with enhanced sequential actuation|
|US6394332 *||May 22, 2001||May 28, 2002||Hitachi Koki Co., Ltd.||Nail gun with safety portion mechanism for preventing misfires|
|US6422446 *||Dec 28, 2000||Jul 23, 2002||Park Liu||Adjusting apparatus of a trigger of a pneumatic nailer|
|US6641018 *||Apr 11, 2002||Nov 4, 2003||Hitachi Koki Co., Ltd.||Nail gun with safety portion mechanism for preventing misfires|
|US6820788 *||Sep 11, 2003||Nov 23, 2004||Hitachi Koki Co., Ltd.||Nail gun with safety portion mechanism for preventing misfires|
|DE3021884A1||Jun 11, 1980||Jan 22, 1981||Duo Fast Corp||Eintreibgeraet fuer befestigungsmittel|
|DE3703753A1||Feb 7, 1987||Aug 18, 1988||Haubold Kihlberg Gmbh||Driving-in device (tacker) for fastening means having a triggering safety device|
|DE4032231A1||Oct 11, 1990||Jun 20, 1991||Behrens Ag Friedrich Joh||Nail driving machine with safe release mechanism - comprises feeler to contact work object and control trigger mechanism activating release lever|
|JPH0553873U||Title not available|
|JPH0647665A *||Title not available|
|JPH0647665Y2||Title not available|
|JPH0647667Y2||Title not available|
|JPH0727093Y2||Title not available|
|JPH0753907A *||Title not available|
|JPH0753907Y2||Title not available|
|JPH04136677U||Title not available|
|WO2000016947A1||Sep 15, 1999||Mar 30, 2000||Stanley Fastening Systems, L.P.||Multi-stroke fastening device|
|U.S. Classification||227/8, 227/130|
|International Classification||B25C1/00, B25C1/04|
|Apr 25, 2012||FPAY||Fee payment|
Year of fee payment: 8
|May 12, 2016||FPAY||Fee payment|
Year of fee payment: 12