Patent Publication Number: US-2022234180-A1

Title: Nail gun

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims priority of Taiwanese Patent Application No. 110102819, filed on Jan. 26, 2021. 
     FIELD 
     The disclosure relates to a nail gun, and more particularly to a nail gun that is capable of switching between different firing modes. 
     BACKGROUND 
     In order to prevent safety hazards and to comply with certain industrial regulations, a conventional nail gun generally includes a safety unit and a trigger unit that are configured as two switches that cooperate with each other to determine whether to initiate a nail-striking action so as to ensure the safety of a user. However, the safety mechanism of such conventional nail gun can only operate under a sequential firing mode or a continuous firing mode, not both. 
     SUMMARY 
     Therefore, the object of the disclosure is to provide a nail gun that is capable of switching between different firing modes. 
     According to the disclosure, a nail gun includes a frame unit, a power unit, a switch unit, a safety unit and a trigger unit. 
     The power unit is mounted to the frame unit, and is configured to drive a nail-striking action during a driving process. The switch unit is mounted to the frame unit, and includes a first switch and a second switch configured to initiate the driving process when both actuated. The safety unit is operable to convert between a non-triggerable state where the safety unit is distal from the first switch, and a triggerable state where the safety unit actuates the first switch. The safety unit includes a moving assembly that is movable relative to the frame unit along a moving path. 
     The trigger unit includes a trigger and an operating member. The trigger is pivotally mounted to the frame unit, and is pivotable between a sequential firing position and a continuous firing position. The operating member is pivotable between the trigger and the second switch. 
     When the safety unit is in the triggerable state, and when the trigger is pivoted from the sequential firing position toward the second switch, the operating member is moved by the trigger to contact the safety unit, to thereby actuate the second switch to initiate the driving process, after which the operating member separates from the moving path of the moving assembly of the safety unit so as to prevent initiation of subsequent driving process. 
     When the trigger unit is pivoted from the continuous firing position toward the second switch, and when the safety unit is converted from the non-triggerable state into the triggerable state, the moving assembly of the safety unit comes into contact with the operating member to initiate the driving process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings, of which: 
         FIG. 1  is a side view of an embodiment of a nail gun according to the disclosure; 
         FIG. 2  is a fragmentary and partially exploded perspective view of the embodiment; 
         FIG. 3  is a fragmentary sectional view taken along line III-III in  FIG. 1 ; 
         FIG. 4  is a fragmentary sectional view taken along line IV-IV in  FIG. 3 , illustrating a safety unit of the embodiment in a non-triggerable state, and a trigger of the embodiment at a sequential firing position; 
         FIG. 5  is a fragmentary sectional view similar to  FIG. 4 , but illustrating the trigger being pivoted toward a second switch of the embodiment; 
         FIG. 6  is a fragmentary sectional view similar to  FIG. 5 , but illustrating the safety unit in a triggerable state; 
         FIG. 7  is another fragmentary sectional view similar to  FIG. 4 , but illustrating the safety unit in the triggerable state where a first switch of the embodiment is actuated; 
         FIG. 8  is a fragmentary sectional view similar to  FIG. 7 , but illustrating the trigger being pivoted toward the second switch and an operating member of the trigger unit actuating the second switch; 
         FIG. 9  is a fragmentary sectional view similar to  FIG. 3 , but illustrating the trigger being pivoted to a continuous firing position via a switching member; and 
         FIG. 10  is a fragmentary sectional view taken along line X-X in  FIG. 9 , illustrating the safety unit in the triggerable state. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 and 2 , an embodiment of a nail gun according to the disclosure includes a frame unit  1 , a power unit  2 , a switch unit  3 , a safety unit  4  and a trigger unit  5 . 
     Referring to  FIGS. 2, 3 and 4 , the frame unit  1  includes a main body  11 , a muzzle  12  that is connected to the main body  11 , and a magazine  13  that is connected to the muzzle  12 , and that is adapted for loading a plurality of nails (not shown) and for sending the nails to the muzzle  12  in a consecutive manner. 
     The main body  11  has an inlet passage  111  adapted for guiding a pressurized gas into the power unit  2 , a switch passage  112 , a first valve room  113  in fluid communication with the switch passage  112 , a second valve room  114  in fluid communication with the inlet passage  111 , and a connecting passage  115  disposed between and in fluid communication with the first valve room  113  and the second valve room  114 . In the present embodiment, the first valve room  113  and the second valve room  114  are arranged along a moving direction (Y). The first valve room  113  has a first neck section  116 , and the second valve room  114  has a second neck section  117 . 
     The power unit  2  is mounted to the main body  11  of the frame unit  1 , is configured to drive a nail-striking action during a driving process, and includes a cylinder  21 , a piston  22  (see  FIG. 8 ), and a striking member  23 . The cylinder  21  is adapted for receiving the pressurized gas guided by the inlet passage  111  of the frame unit  1 . The piston  22  is movably disposed in the cylinder  21  and is adapted to be driven by the pressurized gas to move. The striking member  23  is co-movably connected to the piston  22  and is configured to perform the nail-striking action. 
     Specifically, in the present embodiment, the cylinder  21  is a movable cylinder, which is adapted to be driven by gas guided by the switch passage  112  of the frame unit  1  to move relative to the main body  11  between a closed position (see  FIG. 4 ) and an open position (see  FIG. 8 ). When the cylinder  21  is at the closed position, fluid communication between the cylinder  21  and the inlet passage  111  of the main body is blocked, such that the pressurized gas is prevented from entering the cylinder  21  through the inlet passage  111 . When the cylinder  21  is at the open position, a gap is formed between the cylinder  21  and the main body  11  of the frame unit  1 , such that the cylinder  21  and the inlet passage  111  are in fluid communication, and the pressurized gas is thus allowed to enter the cylinder  21  through the inlet passage  111 . Since the working principle of the aforementioned movable cylinder is well known in the art and not the feature of the present embodiment, no further description will be given hereinafter. 
     It should be noted that, the power unit  2  of the nail gun is not limited to being powered by means of pressurized gas, but may also be powered by fuel combustion or electric power, the relevant techniques of which are also well known in the art and thus will not be further described hereinafter. 
     The switch unit  3  is mounted to main body  11  of the frame unit  1 , is adapted to control the pressurized gas to be input into the cylinder  21 , and includes a first switch  31  and a second switch  32  that are arranged along the moving direction (Y), and that are configured to initiate the driving process when both being actuated. 
     The first switch  31  is installed in the first valve room  113 , and is configured to control the fluid communication between the first valve room  113  and the switch passage  112 . The second switch  32  is installed in the second valve room  114 , and is configured to control the fluid communication between the second valve room  114  and the connecting passage  115 . 
     Specifically, the first switch  31  has a first valve rod  311  that movably blocks the first neck section  116  of the first valve room  113 , and a valve rod-biasing resilient member  312  that is disposed between the main body  11  and the first valve rod  311  for biasing the first valve rod  311  so as to openably block the fluid communication between the first valve room  113  and the switch passage  112 . The second switch  32  has a second valve rod  321  and a valve member  322  that are movably disposed in the second valve room  114 . In the present embodiment, the valve member  322  is ball-shaped, is adapted to be forced by the pressurized gas to block the second neck section  117  of the second valve room  114  so as to openably block the fluid communication between the second valve room  114  and the connecting passage  115 , and is configured to be pushed by the second valve rod  321  to unblock the second neck section  117  of the second valve room  114 . 
     Referring to  FIGS. 1, 2 and 4 , the safety unit  4  includes a moving assembly  400  that is movable relative to the frame unit  1  along a moving path, and is operable to convert between a non-triggerable state where the safety unit  4  is distal from the first switch  31 , and a triggerable state where the safety unit  4  actuates the first switch  31 . 
     Specifically, the safety unit  4  further includes a sleeve member  40 , a safety member  41 , an extending member  42 , a safety member-biasing resilient member  43 , and an extending member-biasing resilient member  44 . The sleeve member  40  is connected to the frame unit  1 , extends along a length direction (X), and has two open ends being opposite along the length direction (X). The first valve rod  311  of the first switch  31  and the extending member  42  extend into the open ends of the sleeve member  40 , respectively. In the present embodiment, the length direction (X) is substantially perpendicular to the moving direction (Y). 
     The safety member  41  extends along the length direction (X), is movably mounted to the frame unit  1  between the main body  11  and the muzzle  12 , and has an abutting end  411  proximate to the switch unit  3 , and a workpiece-engaging end  412  opposite to the abutting end  411  and adapted to be pressed by a workpiece (not shown). The extending member  42  abuts against and is disposed between the safety member  41  and the first valve rod  311  of the first switch  31 . When the safety unit  4  is in the triggerable state, the extending member  42  presses against the first valve rod  311  to open the fluid communication between the first valve room  113  and the switch passage  112 . The extending member  42  cooperates with the safety member  41  to constitute the moving assembly  400 . 
     The safety member-biasing resilient member  43  is disposed between the muzzle  12  of the frame unit  1  and the safety member  41  for biasing the workpiece-engaging end  412  of the safety member  41  away from the frame unit  1 . The extending member-biasing resilient member  44  is disposed between the sleeve member  40  and the extending member  42  for biasing the extending member  42  away from the first valve rod  311  of the first switch  31 . 
     The trigger unit  5  includes a trigger  51 , an operating member  52 , a switching member  53 , and a trigger-biasing resilient member  54 . 
     The trigger  51  is pivotally mounted to the frame unit  1 , and is pivotable between a sequential firing position (see  FIGS. 3 to 6 ) and a continuous firing position (see  FIGS. 7 and 8 ). 
     The operating member  52  is movably disposed between the trigger  51  and the second switch  32 , is contactable with the safety unit  4 , and is configured to be driven by the trigger  51  to actuate the second switch  32 . The operating member  52  has a pivot end  521  that is pivoted to the trigger  51 , a distal end  522  that is opposite to the pivot end  521  and that extends removably into the moving path of the moving assembly of the safety unit  4 , and a pressing portion  523  that is connected between the pivot end  521  and the distal end  522  and that is configured for pressing against and actuating the second switch  32 . Specifically, the operating member  52  is configured to press against the second valve rod  321  of the second switch  32  so as to open the fluid communication between the second valve room  114  and the connecting passage  115 . 
     The switching member  53  rotatably extends through the main body  11  of the frame unit  1 , is disposed between the cylinder  21  and the first switch  31 , and has an eccentric shaft  531  extending rotatably into the trigger  51 . The switching member  53  is rotatable to move the eccentric shaft  531  toward the first switch  31  along a moving direction (Y) so as to pivot the trigger  51  to the sequential firing position, and is rotatable to move the eccentric shaft  531  away from the first switch  31  along the moving direction (Y) so as to pivot the trigger  51  to the continuous firing position. 
     The trigger-biasing resilient member  54  is disposed between the trigger  51  and the main body  11  of the frame unit  1  for biasing the trigger  51  away from the switch unit  3 . 
     Referring to  FIGS. 1 to 6 , an operation of the nail gun of the present embodiment is described as follows. 
     Prior to the operation, as shown in  FIG. 1 , the trigger  51  is distal from the second switch  32 , and the moving assembly  400  of the safety unit  4  (i.e., an assembly of the safety member  41  and the extending member  42 ) is biased by the safety member-biasing resilient member  43  and the extending member-biasing resilient member  44 , such that the workpiece-abutting end  412  of the safety member  41  protrudes out of the muzzle  12 . 
     Referring to  FIGS. 3 and 4 , when the switching member  53  is rotated such that the eccentric shaft  531  is moved slightly toward the first switch  31  along the moving direction (Y) to pivot the trigger  51  to the sequential firing position, if the trigger  51  is first pressed to move the pivot end  521  of the operating member  52  toward the second switch  32  (see  FIG. 5 ), the distal end  522  of the operating member separates from the moving path of the moving assembly  400  of the safety unit  4 , such that the pressing portion  523  of the operating member  52  is prevented from actuating the second switch  32 , which then prevents initiation of subsequent driving process. 
     Referring further to  FIG. 6 , at this time, if the workpiece-engaging end  412  of the safety member  41  is pressed by the workpiece such that the extending member  42  moves toward and actuates the first switch  31 , the second switch  32  will not be actuated by the operating member  52  since the distal end  522  of the operating member  52  is separated from the moving path of the moving assembly  400  and cannot be driven by movement of the extending member  42 , and the subsequent driving process is still prevented from initiation. 
     Referring to  FIGS. 4, 7 and 8 , when the trigger  51  is at the sequential firing position, and when the workpiece-engaging end  412  of the safety member  41  is pressed by the workpiece first and moves the extending member  42  toward the first switch  31  (i.e., the safety unit is converted to the triggerable state), the extending member  42  pushes the first valve rod  311  of the first switch  31  along the length direction (X) to unblock the first neck section  116  of the first valve room  113  (i.e., allowing fluid communication between the first valve room  113  and the switch passage  112 ), and the distal end  522  of the operating member  52  is pushed by the abutting end  411  of the safety member  41  toward the second switch  32 . Then, when the trigger is pivoted from the sequential firing position toward the second switch  32 , the pressing portion  523  of the operating member  52  is moved by the trigger  51  to actuate the second switch  32  (i.e., pushing the second valve rod  321  along the length direction (X) to further push the valve member  322  away from the second neck section  117  of the second valve room  114 ), thus allowing fluid communication between the second valve room  114  and the connecting passage  115  to initiate the driving process. 
     After the initiation of the driving process, the pressurized gas enters the second valve room  114  via the inlet passage  111 , and then travels through the connecting passage  115 , the first valve room  113  and the switch passage  112  and into the cylinder  21 . Next, the cylinder  21  is driven to move from the closed position to the open position such that the pressurized gas traveling from the inlet passage  111  is allowed to enter the cylinder  21  via the gap between the cylinder and the main body  11 , so as to drive movement of the piston  22  and the striking member  23  to perform the nail-striking action (i.e., to strike the nail in the muzzle  12 ). 
     When the driving process is completed, a recoil of the nail gun will cause the moving assembly  400  (i.e., the assembly of the safety member  41  and the extending member  42 ) to bounce briefly away from the first switch  31 , which further causes the operating member  52  to become separated from the moving path of the moving assembly  400  (see  FIG. 6 ). At this time, the subsequent driving process is prohibited. That is, the driving process and the nail-striking action can only be re-executed when the trigger  51  and the safety member  41  are both released, thus preventing safety hazards. 
     Referring to  FIGS. 7 and 8 , when the switching member  53  is rotated such that the eccentric shaft  531  is moved slightly away from the first switch  31  along the moving direction (Y) (see  FIG. 9 ) to pivot the trigger  51  to the continuous firing position, the trigger unit  5  as a whole is moved slightly toward the cylinder  21  (see  FIGS. 3 and 9 ). As a result, when the trigger  51  is first pressed to move the pivot end  521  of the operating member  52  toward the second switch  32 , the distal end  522  of the operating member  52  remains in the moving path of the moving assembly  400 . Next, when the workpiece-engaging end  412  of the safety member  41  is pressed by the workpiece such that is safety unit  4  is converted to the triggerable state, the first switch  31  and the second switch  32  are actuated by the extending member  42  and the pressing portion  523  of the operating member  52 , respectively, to initiate the driving process. When the driving process is completed, as long as the trigger  51  is not released, the first switch  31  and the second switch  32  may be easily re-actuated by pressing the workpiece-engaging end  412  of the safety member  41  against the workpiece again, and the driving process may be repeated as many times as needed. 
     It should be noted that, when the trigger  51  is at the continuous firing position, the distal end  522  of the operating member  52  is always in the moving path of the moving assembly  400  even when the moving assembly  400  is bouncing away from the first switch  31  during the recoil of the nail gun. Therefore, as long as the safety member  41  is pressed by the workpiece and the trigger  51  is pulled, the driving process will always be initiated to perform the nail-striking action. 
     In sum, the present embodiment of the nail gun has benefits as follows. 
     By virtue of the first switch  31  and the second switch  32 , the present embodiment of the nail gun is able to ensure the safety of a user as well as complying with industrial regulations. Further, by virtue of the configurations of the switching member  53  and the trigger  51 , the present embodiment can be easily switched between sequential firing mode and continuous firing modes as desired, providing the user with a more flexible and convenient option compared with the prior art. 
     In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiment. It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects, and that one or more features or specific details from one embodiment may be practiced together with one or more features or specific details from another embodiment, where appropriate, in the practice of the disclosure. 
     While the disclosure has been described in connection with what is considered the exemplary embodiment, it is understood that this disclosure is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.