TWI792049B - Spring energized fastening tool - Google Patents

Abstract

A spring energized fastening tool with compact, rigid, low friction working elements is disclosed. A torsion power spring includes forward extending arms with the arms pressing each other proximate a front distal end of the spring. A cantilevered lever links to a handle and engages the spring adjacent to the striker. A bottom loading staple track unlatches and opens through a simple pulling-out action. Structures are provided to enable fitment with a formed sheet metal handle and housing. The fastening tool is particularly simple to assemble, powerful, and of low operating effort.

Description

Spring-Energized Fastening Tools Cross References to Related Applications

This application claims priority to Provisional Patent Application No. 62/895,475, filed September 3, 2019, and Provisional Patent Application No. 62/843,553, filed May 5, 2019, the contents of which are incorporated herein as a reference.

field of invention

This invention relates to several types of spring-energized staplers. More particularly, the present invention relates to a stapler having improved efficiency of assembly and operation.

Background of the invention

Nail gun staplers and the like are known which store energy via a power spring. The deflection of the spring stores energy for a sudden release to impact and drive the fastener into the workpiece. Power spring based drive tools, most commonly associated with manually operated hand tools such as nail guns, can also be operated with electric systems. Power springs may include compression type, long rod or torsion wire springs. With hand nailers, tool housings may consist of die-cast or resin-cast formed sheet metal. Sheet metal construction is most commonly associated with compression springs and less commonly with rod springs. One example of a stapler embodied in sheet metal is the stapler of the trademark T-50, however many others of this type are known. Torsion springs are generally associated with molded or die cast housings; these effectively provide support and guidance for operating the torsion spring.

Various springs are available for use where the striker exits from the normal position in front of the staple or fastener track A low-start stapler in which the work cycle is started in a rest position, and a high-start stapler in which the striker is normally stationary over the staple track to start the work cycle. In either case, there must be a release system to suddenly release the striker for immediate downward movement under spring bias to eject the fastener. Common release systems for one or both are imprecise and a source of friction that increases force.

A guide for staples or fasteners is positioned along the bottom of the tool. Among other known configurations, the staples can be inserted from the rear or from the bottom. Rear loading designs are prone to jams because staples that jam near the front of the track are not easily accessible. Bottom loading exposes the entire staple storage area for access when the track slides back out. A track pull with a latch structure is required to keep the track in its working position. Such latches can be bulky and require sacrificing aesthetics.

Summary of the invention

In various preferred embodiments, the present invention is directed to a spring-energized fastening tool having a compact, low-friction working element. In preferred high origin embodiments, a torsion power spring includes at least two forward arms, wherein the arms press against each other proximate the distal leading end of the spring. One embodiment has a rigid movable four-bar assembly that connects the handle to the power spring and deflects the spring to separate and deflect the arms immediately after depressing the handle. Another embodiment has a cantilevered lever engaging the spring adjacent the striker. A release link is preferably nested within a front portion of the handle, whereby the release link moves directly with the handle about a common pivot hinge during a release portion of the handle's stroke. This structure provides a reliable and repeatable release action.

Various preferred configurations are provided to enable cooperation with a formed sheet metal handle and housing. The structures shown are all compatible to fit within the confines of a standard T-50 style stapler, for example, but are also suitable for use with other sheet metal staplers embodied in molding and die casting. As for assembly, the fastening tool is particularly easy to assemble, powerful, and operates with low effort.

In a preferred embodiment, among other housing structures, the bottom loads staples Tracks are compatible with sheet metal housings. The track unlocks and opens with a simple pull motion.

10: shell; shell body

11: Shell notch

12: front cover; cover

12a: Bottom raised leading edge

12b: uplift

13: Slotted firing pin

16: staple stopper; tab

16a: Tongue

17: shell tongue; tongue

18: Shake the mouth

19: alignment notch; notch

20: handle

22: pivot hinge; hinge; hinge pin; link hinge; link hinge pin; pin

25: shock absorber

27: Pivot

28: Handle Link Pivot Bracket

30: connecting rod

32: Pivot

33: slotting

37: Ribs

40: leverage

41:Hinge

43: hinge; hinge pin; central pivot

45: pivot tab; lever pivot tab

47: lever tongue; tongue

48: lock

50,50a:Latch

53: Tongue

53a: Backend

54: tongue; latch tongue

55: Tongue

56: Latch tab

57: Concave

60: connecting rod

65: Groove

66: connecting rod hole; hole; second connecting rod hole

67: opening

68: Tongue

70: striker

70a: where the extension 72a contacts the blade 78

71: Tongue

72: side wall

72a: Extension

74: Opening or edge

75: beveled surface

76: turning or deflection

78: blade; end of firing pin

79: opening; striker hole; hole; spring opening

90: power spring; spring

91: tip

92: spring arm

93: spring coil

94: power spring arm; spring arm; arm

95: spring arm tip; tip; powered spring arm tip

96: pivot; hinge pin; hinge element; element; pivot/support element; pivot element; support element; spring pivot element; spring element

106: mandrel

107: mandrel pin; mandrel; pin

110: hinge pin; handle hinge pin; pin; handle hinge; hinge

120: Orbit Room

122: side slot

123a: block edge; edge

124: detent

125: retaining rib; rib

126: track spring contact tab; spring contact tab; tongue

127: hole

127a: Track chamber tab

128: U-shaped nail storage guide groove

129: track chamber tongue; tongue

130: Latch bias spring; reset spring

133: spring coil

134: Backend

140: latch spring; deflection spring; spring; track spring

143: spring ring; ring

146: spring front end

147:Backend

150: buffer

155: (housing) board

156: slotting; notch

157: hole

158: edge

160: track handle

161: Pivot

166: side

167: track pulling arm; arm

167a: arm margin

180: staple track

181: Track bracket

182,183: notches

184: ribs; track ribs

184a: track tongue; track tongue; tongue

184b: Ribs

185: track wall

186: fulcrum; notch

187: Track Foot

187a: Tongue

188: rail guide tongue; tongue

189: Concave

190: reset spring

192: spring arm

193: beveled outriggers; outriggers

194: outrigger

200: Propeller spring

202: Ring

322: Connecting rod tongue

328: handle link bracket

329: slotting

330: lever connecting rod; connecting rod

332: Hem

333:Hinge

335: Tongue

340: leverage

341: Lever Pivot; Rear Pivot; Operating Pivot

343:Central lever pivot; central pivot; operating pivot

344: notch

348: edge

349:Fragment

366: opening; lever front opening; pivot; operating pivot

400: Spring Driven Thruster

405: Standard U-shaped nail rack

L: imaginary vertical line; line; vertical line; approximate vertical line

L1, L3: distance

L2: distance; short cantilever; fragment

W: size

The partial cutaway side elevational view of Figure 1 illustrates a fastening tool in a rest state according to a specific embodiment.

FIG. 1A is a detail view of FIG. 1 illustrating the lower front corner region.

FIG. 2 is a rear top perspective view of the fastening tool of FIG. 1 .

Figure 3 shows the tool of Figure 1 in a depressed state.

FIG. 3A is a detailed view of the top frontal region of the tool of FIG. 3. FIG.

Figure 4 shows the tool of Figure 1 in a pre-release condition.

FIG. 4A is a detailed view of the top frontal region of the tool of FIG. 4. FIG.

4B is a partial cross-sectional view of the frontal region of the tool of FIG. 4. FIG.

Figure 5 shows the tool of Figure 1 in a released state.

FIG. 5A is a detailed view of the top frontal region of the tool of FIG. 5. FIG.

FIG. 6 is a front perspective view of the tool of FIG. 5 .

Figure 7 is a front top perspective view of the handle link pivot bracket.

Figure 8 is a front perspective view of the handle for levering the linkage.

Figure 9 is a rear perspective view of the release latch.

Figure 10 is a top front perspective view of the lever.

Figure 11 is a bottom perspective view of the rear of the striker.

Figure 12 is a front top perspective view of a link bar.

Figure 13 is a top front perspective view of the front cover.

The side elevation view of Figure 14A illustrates the power spring at rest.

Figure 14B is the spring of Figure 14A with the spring shown in phantom partially deflected and the spring in a depressed state.

Figure 14C is a top perspective view of the spring of Figure 14A.

Figure 15 is a top front perspective view of the bumper assembly.

Figure 16 is a side elevational view of the fastening tool at rest showing several working components according to an alternate embodiment.

Figure 17 is a cutaway side elevation view of the tool of Figure 16 in a pre-release state.

Figure 18 illustrates the assembly steps of the upper handle sub-assembly to the lower stapler structure.

Figure 19 is a detailed perspective view illustrating the handle and lever linkage set during an assembly step.

20 is a top rear perspective view of the rear handle link pivot bracket according to this alternate embodiment.

Figure 21 illustrates a rear perspective view of a handle for a prying link according to this alternate embodiment.

Figure 22 is a side rear perspective view of a lever according to this alternate embodiment.

Figure 23 is a rear elevational view of the connecting rod of Figure 21.

Figure 24 is a partial cutaway side bottom perspective view of a track subassembly.

24A is a top side perspective detail view of the track subassembly of FIG. 24. FIG.

Figure 25 is a rear detail view of the track subassembly of Figure 24 with the track in an unlocked state and moving to open.

25A is a top side perspective detail view of the track subassembly of FIG. 25. FIG.

Figure 25B is the view of Figure 25A with the track being moved to the closed position.

Figure 26 is a front side perspective view of the track subassembly of Figure 24 with the track pulled out for loading with staples.

Figure 27 is a bottom front perspective view of the track handle.

Figure 28 is a bottom front perspective view of the track handle bias spring or latch spring.

Figure 29 is a side bottom perspective view of the track guide chamber.

Figure 30 is a side bottom perspective view of the staple track.

The bottom side perspective view of Figure 31 shows the stapler in an upside-down orientation ready for bottom loading of staples and fasteners with the track in the closed working position.

Figure 32 is a cropped view of the stapler of Figure 31 with the track handle unlocked.

32A is a detailed view of the stapler of FIG. 32. FIG.

Figure 33 illustrates the stapler of Figure 32 with the track partially open to expose the staple loading chamber.

Figure 34 is a detailed rear top perspective view of the stapler of Figure 33 in an upright position.

35 is a graph of handle force F (y-axis) versus travel distance ID (x-axis) illustrating the performance advantages of a rigid handle and spring linkage set.

The present invention is directed to a compact, efficient spring-energized stapler operable and housed within a formed sheet housing body or similar standardized body. The accompanying drawings illustrate a preferred embodiment stapler that is sized and shaped to have a body similar to known commercially available staplers for use with a T-50 up to ½ inch or 9/16 inch long Style staples work together. However, the features of the present invention may be used with staplers having other shapes, sizes and constructions including molded resin and die cast. For example, one or both of the housing 10 and the handle 20 may comprise sheet metal, molded resin, and/or die-cast metal. When describing staplers, the term may include nail guns, nail guns, and equivalent fastening tools, whether electrically or manually, with a power spring energized.

In the preferred embodiment stapler of FIG. 1, for example, the tool is 7-1/4 inches long from rear end to front end. In FIG. 4B, the dimension W of the housing 10 (W is about twice 0.45 inches to include the opposite side of the housing not shown) is approximately 0.9 inches wide in total. Other sizes, shapes and dimensions of housings, handles and other working components are contemplated.

In the assembled view of FIGS. 1-6 , the right side of the housing is removed and the handle 20 is depicted in section to reveal the internal components. The housing 10 has a front (right side in FIG. 1 ), a back, a top and a bottom. Figure 1 illustrates the stationary state of the stapler. The handle 20 is in an upper level position above the housing 10 and it is pivotally attached to the housing 10 at a handle/housing pivot where the hinge pin 110 is near the top of the housing. At the bottom of the housing 10 is a staple track 180 that supports staples that are biased forward by the spring driven pusher 400 . The handle link pivot bracket 28 includes the pivot hinge 22 . The linkage 30 has a pivot 32 mounted to the hinge 22 defining the upper end of the linkage assembly or equivalent. The lower end of the link 30 includes a slot 33 that engages the hinge 43 of the lever 40 . Also refer to Figures 7 to 15 for individual components. The lever 40 includes a pivot tab 45 that engages a groove 65 of the connecting rod 60 . The linkage rod 60 engages the pivot, hinge pin or hinge element 96 of the power spring 90 at the linkage rod aperture 66 . Aperture 66 may define the lower end of the linkage assembly where hinge 22 begins or an equivalent structure. The lower end of the connecting rod set is lower than the upper end of the connecting rod set and substantially in front thereof. As can be seen from FIG. 1 , an imaginary vertical line L between the pivot structure of hinge pin 110 and member 96 is well in front of hinge 22 ;

As can be seen from FIGS. 2 and 3 , the power spring 90 pivots around the spindle 106 . Power spring arm 94 extends from spring coil 93 to spring arm tip 95 . The tip 95 preferably engages the opening 79 of the striker 70 as shown, either directly or through another coupling member in the nearest local location. The latch 50 is preferably pivotally attached to the tool assembly with a recess 57 at the handle hinge pin 110 . In FIG. 3A, the tab 54 of the latch 50 engages the opening or edge 74 of the striker 70 to selectively immobilize the striker.

The movement of the above components is illustrated by comparing FIGS. 1 and 3 . Depressing the handle 20 centered on the hinge pin 110 causes the link 30 to move downward. Pivoting of lever 40 about hinge 41 causes linkage rod 60 to move downward. Thus, the linkage assembly forces the spring arm 92 to deflect downwardly or in an equivalent direction. The action of the latch 50 prevents the downward movement of the striker 70 so that, as seen in the depressed position of FIG. 3 , the spring arm 94 remains in the upper position. Power spring 90 is deflected by spring arm 92 spaced from spring arm 94 . The power spring 90 is thereby energized for a duty cycle to eject the fastener from the track 180 . In FIG. 3A, the hinge pin 22 is just in contact with the tongue 53 of the latch 50 while the handle 20 is in the low but not lowest position. The handle is further towards the lowest position in Figure 4 Movement initiates rotation of the latch 50 to disengage the striker 70, as described next.

In FIGS. 4 and 4A , the pre-release state has the latch 50 disengaged from the striker 70 . Tab 54 is away from opening 74 so that striker 70 is now free to move downward. The release of the striker 70 is preferably as close as possible to the lowest position of the handle. This lowest handle position of FIG. 4 is defined by the contact or equivalent action of the shock absorber 25 of the handle 20 against the surface of the housing 10 . Thus, the handle 20 has minimal jump or jerk when released to reduce operator fatigue. In addition, the force of the operator's palm presses directly against the housing body 10 through the shock absorber 25 to help the stapler stay down when fired. To move the latch 50 as described above, the pin or equivalent structure of the hinge 22 presses against the latch's tongue 53 . The latch 50 is rotated about the hinge pin 110 to slide the tab 54 out of the striker 70 . The preferred latch movement is precise, reliable and repeatable because it is directly bound to the short part of the handle movement; the latch only starts moving late in the handle stroke so that its release movement is relatively fast during the associated handle movement . Specifically, this latch release movement only occurs between the depressed handle position of FIG. 3 and the pre-release position of FIG. 4, which is approximately ½ inch on the back of the handle on the exemplary model shown. With all latch release motion concentrated near the end of the stroke, any tolerance variation in the position of the pre-release handle will be confined to a predetermined position within a small fraction of handle motion. The latch 50 operates about a common pivot with the handle 20 so that there is no tolerance variation in the intervening components; the latch and handle move jointly during release. There is also minimal net vertical force on the hinge pin 110 because the handle 20 and latch 50 pull back on the pin. Thus, the pin 110 can rotate with the handle 20 about its mount on the housing 10 with little force and friction on the housing mount. This combined motion reduces the friction between the latch 50 and the pin 110 as shown in the working model and by empirical testing.

In FIGS. 4A , 9 , the exemplary embodiment tab 54 has a preferred acute angle of about 89 degrees relative to an imaginary radial line extending from the hinge pin 110 . Angles within about 2 to 5 degrees of 90 degrees may be suitable to hold the latch 50 stable on the striker with the minimum force required to move the latch as described above on the latch. It has been empirically observed that, with the exemplary angle of 89 degrees, rotation of the latch 50 under load as shown in Figures 3 and 4 during the release action increases the peak handle force by less than 1 pound, here approximately ½ pound . This force is effectively invisible to the user. A total force of approximately 15 to 16 pounds is required to provide sufficient Power to drive ½ inch T-50 staples into common construction lumber applications such as Douglas fir. Thus, the stapler provides great staple driving power while the handle deflection force perceived by the user is low and smooth.

The link set passing through the structure described herein between the handle 20 and the striker 70 is substantially rigid. In the spring rest state of FIGS. 1 , 14A and 14C , the pivot/support member 96 presses against the spring arm 94 to keep the power spring 90 pre-compressed. 3 and 14B illustrate the power spring being deflected and energized. Pivot member 96 is preferably a lateral extension of the spring arm and may be referred to as a "preload position" or spring preloaded preload position that is spaced from coil 93 to enable preload torque on the coil. The transverse direction enters the page of Fig. 1 and Fig. 18, and it is preferably but not necessarily perpendicular to the arm 94 of Fig. 14C. Referring to Figure 14C, the spring arms may cross at a shallower angle. The pressing is preferably directly between the respective arms 92, 94 while the arms are also pressed into localized areas by further elements. Pivot member 96, preferably but not necessarily, forms a hook with tip 91 to hold the spring in a precompressed state in the precompressed position. When the handle is depressed by the user, the pivot member 96 is forced downward. The force on the striker 70 at the tip 95 increases from near zero to a final maximum in the pre-release position of FIG. 4 . This force is a torsion force on the spring arm 94 . The spring arms 92, 94 are functionally and intentionally made resilient material, typically the same wire as the coil. However, as described below, deflection in front of the preload position is not useful; therefore, the length of the portion in front of pivot member 96 is minimized in the preferred embodiment.

To demonstrate this minimized frontal length, in FIGS. 1 , 14A-14C , the spring arm 94 flexes proportionally to the latter's length: between the pivot/support element 96 and the striker position at the tip 95 An unsupported cantilever segment of . This effect is shown graphically in FIG. 14B : in dashed line, the support element 96 is pressed down slightly from FIG. 14A until the element 96 no longer presses against the spring arm 94 . Spring arm 94 flexes as shown until support element 96 no longer contacts S1. In the event of a loss of support at S1, the support element moves further forward to the striker at S2. This deflection to remove the preload is transferred to the handle 20 as an ambiguous start of stroke and a loss of energy input, as described below in describing FIG. 35 . Therefore, as shown and discussed separately above, it is best to have S1 as close as possible to S2 to minimize the effect of this deflection.

As shown in FIG. 1, the distance from the spindle pin 107 or equivalent coil center axis or spring coil center to the striker 70 is about 2.06 or 2.11 inches. Most preferably, there is a distance of about 2.11 inches, and is indicated by dashed line L1 in FIG. 1 . In this context, the striker position is defined as the rear plane of the striker blade at the engagement opening 79 . The distance from support member 96 to striker 70 is about 0.43 inches, as shown by line L2 in FIG. 1 . L3 is the distance between the spindle pin 107 and the support member 96, and L3 is about 1.70 inches in this particular embodiment. The distance ratio L3/L1 is about 80% (ie, 1.70 inches/2.11 inches). Therefore, the preload position is approximately 80% of the length of the dotted line L1 in front of the coil position. In FIG. 4, this distance places the support element 96 adjacent the striker 70 in a pressed spring condition, preferably no more than one spring wire diameter away from the side wall 72 or other striker structure, however other alternatives relative to the striker are conceivable. interval. A distance ratio L3/L1 above 50% is preferred, however a distance ratio above about 60 or 70% is even more preferred so that the spring arm 92 ends near the striker and thereby the benefits seen below based on empirical observations. Other dimensions proportional to other overall tool sizes are contemplated. The aforementioned ratios or ratios all refer to the rest position of FIG. 1 , however they are not substantially different from the released position of FIG. 5 .

The deflection of the cantilevered spring arm 94 as described above is felt at the handle as "dead bounce" - an ambiguous feeling that is minimized in the present invention as described when describing FIG. 14B. Based on empirical observations and mechanical principles, this deflection wastes handle travel and useful energy input, as described further below in detailing the x-y graph of FIG. 35 . With deflection minimized, the handle 20 is effectively rigidly coupled to the power spring 90 at a position of only about 0.43 inches from the striker 70 by a four-bar cantilever linkage or alternative linkage arrangement described below. Under the short cantilever L2 of the "beam" of the spring arm 94, there is minimal beam deflection and an insensible bounce that is not felt. As a result, the user's effort on the handle is felt to be reduced, and the smooth operation of the handle greatly improves the feel of the tool to the user.

14A-14C are various views of a preferred embodiment power spring 90 . In Fig. 14A and Fig. 14C, the power spring 90 is in a pre-compressed static state. Pivot/support member 96 compresses spring arm 94 in proportion to a preload selected for a particular power spring characteristic. Therefore, the spring has a free position (also That is, not flexing), wherein the spring arm 92 is preferably bent upward and the pivot member 96 is spaced above the arm 94 relative to the view of FIG. 14A. The pre-assembly step assembles the connecting rod 60 to the power spring 90 with the pivot member 96 passing through the hole 66 of the connecting rod 60 ( FIGS. 1 , 2 , 12 ). In a pre-assembly step, the spring arms are then forced to move from the free position to the position depicted in Figures 14A and 14C to form a sub-assembly of connecting rod 60 and power spring 90, wherein the spring is pre-compressed. Tip 91 of power spring 90 preferably passes by spring arm 94 to secure spring arm 94 on pivot member 96 and stabilize the assembly. The assembly preferably has the tip 91 , the connecting rod 60 and the spring arm 94 adjacent each other laterally along the pivot member 96 .

An alternate embodiment tool could use a power spring in the form of a single flat bar spring or assembly rather than a coiled wire torsion spring. The rod spring includes cantilever legs and is preloaded similarly to Figures 14A-14C. The bar spring is mounted to a mandrel 107 or similar fixture inside the housing.

In this embodiment tool, a “four bar” or equivalent rigid linkage forms the linkage assembly to connect the hard steel handle or equivalent rigid structure to the pivot member 96 of the power spring 90 . In this four-bar assembly, a lever 40 is pivotally mounted on its rear at a hinge 41 shown in FIG. 1 . The connecting rod 30 presses the lever 40 at the hinge 43 towards the central portion of the lever 40 and the lever presses the connecting rod 60 at the front distal end of the lever 40 . Lever 40 cantilevers forward from its linkage at hinges 41 and 43, and thus, lever 40 can extend forward to a position adjacent to the striker. In this way, the vertical linear movement of the link hinge 22 from the handle may be enhanced by the cantilever lever 40 at the pivot tab 45 and thus at the pivot element 96 or equivalent structure. As shown in Figures 1 and 3, the vertical travel at link hinge 22 is approximately doubled at pivot tab 45 because the lever is compressed near its center. However, if the hinge 41 is located further back in the housing 10, this multiplied travel is reduced by a factor of 1.1, which still allows for a useful leverage geometry. The substantially vertical alignment of the spring pivot member 96 with the lever pivot tab 45 allows the pivot member 96 to maintain the preferred distance ratio of at least 80% as described above. Thus, the pivot element 96 is also in close proximity to the striker.

All linking elements of the linkage assembly described herein can be made of steel so that the system except There is no apparent or palpable give or gap other than to store spring energy. It is evident from the above geometry that the handle 20 should be rigidly coupled to the power spring 90 at the forward most position of the power spring. As shown in FIG. 1, such a link at the preloaded position adjacent to the pivot member 96 is substantially vertically aligned with the handle hinge 110, which is represented in FIG. Pivot member 96 and hinge 110 are at or near tangent thereto. In other words, line L coincides substantially vertically with each of hinge 110 and pivot member 96 (precompression position). Similar considerations apply eg to FIG. 16 . Likewise, tie bar 60 extends vertically or is approximately aligned below handle hinge 110, coincident vertically in the alignment shown, wherein hinge 110 has some structure overlapping that of element 96 in the top view.

In the four-bar system depicted in Figures 1, 2 and described above, there is a rear bar comprising a housing 10 structure supporting a spring arbor 106 and a hinge 41, a front bar in the form of a connecting bar 60, The upper rod, and the bottom rod which is the spring arm 92. The connecting rod 60 is pivotally guided within the four-bar system with the pivot member 96 of the power spring of FIG. 4B. The torsion spring is therefore particularly suitable for the present four-bar system. The spring arm 92 provides the interface between the two to energize the spring and is also the functionally rigid member of the four-bar system to guide the lower end of the tie rod 60 . These combined functions are not possible, for example, with compression springs which are inherently unstable in the transverse direction.

The x-y graph of Figure 35 depicts empirical observations of unexpected results and the benefits of the rigid structure described above. The graph illustrates comparative test results from a working model of a torsion spring stapler with similar staple performance. It is based on the measurement of the force F at the far or rear end of the handle (y-axis) relative to the handle movement distance D (x-axis) while omitting the initial handle free play but including "inductive bounce" value. The area under each curve corresponds to the energy stored in the power spring. The "long arm" prototype uses the second arm about halfway between the coil and the striker to press the first spring arm with pre-compression, and the configuration will have values close to L2 and L3 in Figure 1. In contrast, the "short arm" sample, pressed with preload closer to the striker pin, has the above-mentioned ratio of about 80%. A steep initial slope in the jib graph indicates a stiff linkage with reduced insensible bounce and quick start to store energy (shown in dashed line in FIG. 14B and described above). The slower slope of the long arm graph indicates additional flex or bendability between the handlebar and the power spring. It can be seen that the handle movement of the long arm is Mass is wasted up to about 0.4 inches of travel, making long-arm staplers require higher handle force for similar performance. Thus, the exemplary embodiment short arm stapler enjoys a measurable performance advantage over long arm stapler designs.

Exemplary embodiments described herein include a tensile link between the striker and the handle while enabling easy assembly of the stapler tool. This is further advantageous because, if the striker jams in the lower position, it is possible to force the striker upwards by pulling on the handle with pulling force. As can be seen from FIG. 1, the connection between the connecting rod 60 and the power spring 90 at the hole 66 is multidirectional in nature. The next connection is between connecting rod 60 and lever 40 . This connection is between the pivot tongue 45 and the groove 65 of the connecting rod 60 . During assembly, the lever 40 is rotated counterclockwise about this connection to engage the tab 68 above the catch 48 . The tab and catch remain engageable for all working positions - eg compare Figures 1 and 3A. There is a slight play to the tongue 68 to ensure that the normal compression operation only engages the pivot tongue 45 with the groove 65 . When the lever 40 is pulled upwards, the catch 48 presses the tab 68 from below to pull the connecting rod 60 upwards, thus powering the spring and striker.

The reset spring 190 biases the associated movable part towards the rest state of Figures 1 and 2 in normal use. Reset spring 190 pivots about leg 194 in bore 157 of bumper 150 according to FIGS. 1 and 15 . In FIG. 2, bumper 150 is omitted to show underlying components. In FIG. 4B , at its upper end, the angled leg 193 engages the opening 67 of the tie rod 60 , wherein the angle of the leg 193 biases the spring arm 192 to stay in the opening.

Including all components below the linkage 30 is preferably initially assembled so that the underlying stapler structure is complete, including the two housing halves and the front cover 12 . Only the components associated with the handle remain attached so that there is no need to secure the various underlying components as the handle is maneuvered into the assembly. This eases assembly work for mass production.

The upper level assembly includes handle 20, shock absorber 25, linkage bracket 28, latch bias spring 130, and linkage 30, as shown in Figs. 1 and 2 . The latch bias spring 130 is supported around the hinge pin 22 in a spring coil 133 and fixed at the rear end 134, as shown in FIG. 3A. These components are pre-assembled to the handle 20 . The linkage 30 hangs loosely from the handle 20 near the linkage hinge 22 prior to installation to the underlying tool structure. In FIG. 2 , the link hinge pins 22 each naturally form a multidirectional link within the holes of the two connecting parts. The pin 22 also supports the latch bias spring 130 when pre-assembled. When the handle sub-assembly is installed, the elements of the substructure are in the static state shown in Figure 1. The latch 50 rests on the lever 40 to rest on the beveled face 75 of the striker 70 in the approximate position shown in FIG. 1 . The stapler body and handle are positioned such that the front of the tool has an upward bevel to allow the lower end of the linkage 30 to drop over the hinge 43 at the linkage slot 33 . Hinge pin 43 ( FIGS. 3A , 10 ) is a pre-installed latch for lever 40 . Rotating the link allows the handle to align at the hinge pin 110 , which at this point is mounted to support both the latch 50 and the handle 20 . This approach has been shown to be effective in working models. In FIG. 3A it can be seen that the rib 37 of the link now cooperates with the lever tab 47 so that pulling up on the handle 20 causes the rib 37 to press the tab 47 from below to transmit a jam-releasing tensile force. Thus, the preferred embodiment stapler benefits from the anti-karaage force that can be used to couple the striker 70 to the handle 20 that is operated by the user. If desired, some or all of the functions of the linkage bracket 28 may be integrated into the handle structure, eg, with a molded polymer composite handle. For example, a recess in the side wall of the handle may support the link hinge pin 22 with the latch bias spring 130 .

The staple is driven by the tool of the present invention, and now in the reset action, the striker 70 goes from the lower release position of FIG. 5 to the upper rest position of FIG. 1 . In FIG. 5A , it can be seen that moving the striker face 75 upwardly causes the latch 50 to rotate counterclockwise in view. This camming continues until the latch tab 54 is aligned with the striker opening 74, eg FIG. 3A. Subsequently, the latch 50 is rotated clockwise under the bias of the reset spring 130 as the tab enters the opening 74 to assume the position of FIG. 1 . The latch 50 now selectively retains the striker 70 in its upper position. Tongue 55 contacts face 75 to secure latch 50 in opening 74 having a radius at the base of tongue 54 as shown in FIG. 1 . In the state shown in FIGS. 5A and 6 , the striker 70 is down and disengaged from the latch 50 . As the handle 20 is raised on the reset stroke, the latch tends to rotate clockwise away from the reset spring 130 . In Figure 3A, the latch 50 has a stop against the housing formed by the housing notch 11 against the latch tongue 56 to limit rotation in the absence of the striker relative to the operative position shown in the figure. Thus, the tongue 54 of the latch 50 remains in a position forward of the face 75 whereby reset camming of the latch and striker can occur.

In FIG. 5 , striker 70 includes a blade or flat defined by its position 78 immediately in front of track 180 . It is desirable to minimize any elements of the tool that extend forward past this location 78 to ensure that the staple can fit reasonably near a confining wall, corner or similar obstruction. Additionally, the compact front of the tool maintains a favorable user line of sight for aiming the tool. In FIGS. 1 , 5A and 13 , the tool includes an optional bump 12b in the front cover 12 to avoid the power spring arm tip 95 . Again, the handle 20 extends forwardly when in the depressed position of Figure 5A, but not farther than the protrusion 12b. To restrain a handle or similar extension, the latch 50 engages the striker 70 at a location behind the blade 78 of the striker 70 . To this end, as can be seen in Figure 4A, the striker 70 includes a dogleg or offset bend 76 whereby the opening 74 is preferably spaced behind the blade 78 or main striker structure. The latch 50 can then be paused and moved behind the blade and/or cover 12 as shown in FIG. 1 . The latch 50 is located near or on top of the striker 70, as shown in Fig. 1 and Fig. 2 . The latch 50 disposed in the upper position of the tool avoids the area occupied by the reset spring 190, bumper 150 and tab 71, as described below. With this configuration, the housing has ample space in the lower frontal area behind the striker for further components that will be assembled, handled and functioning well.

In FIG. 2 , to provide a shock stop against bumper 150 , striker 70 includes a horizontal tab 71 bent from side wall 72 . These tabs 71 contact the bumper 150 in the low striker position of Figure 5, where the striker end 78 is at the bottom of the stapler body. In FIGS. 6 and 11 , in order to reinforce the tongue 71 , the striker 70 includes an extension 72 a that contacts the blade 78 at 70 a immediately above the tongue 71 . These extensions 72a provide a direct force path from the movable body of the striker 70 and power spring tip 95 to the tab 71 to reduce bending stress on the blade structure where the tab meets the side wall 72 .

Common in torsion spring stapler designs, the bumper acts directly on one arm of the power spring, especially, on dry fire without staples, with the bumper directly blocking the spring arm rather than the striker. This results in an undesirable reversal of force in the spring arm type damper. During normal use of the firing tool, the spring arm tip 95 presses down at the striker hole 79 (FIGS. 6, 11) to install the staple. But with the spring arm connected to the bumper contact structure in blank fire, there is inversion at the spring arm/firing pin interface force. The spring arms come to a stop first, and the striker overshoots the spring arm a small distance over the hole 79 and strikes the spring arm at the top of the hole to catch indirectly with the bumper.

This overtravel action causes wear at the top and bottom of the hole 79, creating a flared, twisted or enlarged hole, increasing tensile stress on the striker, and increasing the vertical clearance of the striker around the spring arm. In extreme cases, the hole is oval in shape so that the spring arm cannot raise the striker high enough to set the latch or reach the release height. As described herein, bumper 150 acts directly on striker 70 . Therefore, the striker 70 is always one of an acceleration, a pressing staple, or a pressing buffer. The spring arm 94 at the tip 95 is thus permanently depressed within the bore 79 thereby wearing the bore in only one direction with minimal tensile stress on the striker in this area. It has been empirically observed that this configuration improves the lifetime and working life of the tool.

Furthermore, as far as the spring wire/bumper interface is concerned, the wire spring arms provide a small impact target for the bumper resulting in high stresses in the contact area. In the preferred embodiment, any target zone on the powered spring arm 94 is further interrupted by the useful forward position of the pivot member 96 at the forward distal end of the spring arm 92, which corresponds to the short L2 length of FIG. Although it is advantageous to make this segment L2 short as described above, it may provide a small buffer object. In a configuration where the bumper contacts against or is fixed to the striker, the bumper may be directly vertically below the distal end of the arm 92 , for example at the pivot member 96 . As can be seen clearly from FIGS. 1 and 5 , the bumper 150 extends behind the pivot member 96 . This structure can be described as having an alignment along at least one of the vertical lines of the bumper 150 and the distal end of the arm 92, with the handle hinge 110 also preferably aligned as such above the bumper 150, and the spring coil 93 behind this alignment. In an alternate embodiment, there may be additional or only arm 94 in contact with the bumper or other structure that moves with the striker.

As shown in Figure 11, the strike stop (horizontal tab 71) is bent directly from the striker 70 material to preferably minimize the weight and inertia of the reciprocating strike component, however a separate component could be used. It is best to minimize the mass of the firing pin and any other parts that move during the impact and firing stroke. When these components are kept light in weight, the stapler more efficiently installs staples and the like, especially when actuating the stapler with one hand. As a result, the body comprising the housing 10 does not jump up substantially immediately when the staples are removed, because compared to fast Moving but light striker, heavy body. This gives the user a dampened, less inconsistent vibration feel to the tool and reduced hand fatigue. As shown in Figure 11, the striker 70 includes optional openings above and below the spring opening 79 to further reduce its weight.

Housing 10 preferably comprises two halves. The left half of the diagram is shown in the views of FIGS. 1 to 6 . The halves must be secured in a properly spaced relationship for effective tool function. In FIGS. 1 and 2 , the mandrel 106 is supported by a pin 107 . This pin 107 can be a screw or rivet to compress the housing around the mandrel. Thus, the mandrel 106 keeps the housings firmly spaced apart for the working clearance of the spring 90 and further secures the housing halves from sliding against each other. At the lower front of the housing of Figures 1 and 2, a plate 155 separates the housing when the front cover 12 clamps the housing from the front. Shell plate 155 preferably supports rubber bumper 150 in the bumper assembly shown in FIG. 15 . In the cutaway section of FIG. 1 , track chamber tab 129 extends within slot 156 of plate 155 . Figure 2 also illustrates these components, where buffer 150 is omitted for clarity of illustration. The tab 129 in FIG. 1 provides the exact rear limit position of the track chamber 120 relative to the striker 70 in the upper rest position. In FIG. 2 , striker 70 is positioned laterally by edge 158 of plate 155 . To laterally align plate 155 with track chamber 120 , tab 129 fits snugly in notch 156 . Thus, virtually no tolerance builds up from the more indirect attachment of the plate to the striker and track passing through the housing enclosure.

At the front top part, there is minimal space for a similar board, for example because the latch 50 is advantageously placed there. Preferably, as can be seen in Figures 6 and 13, the front cover 12 includes alignment notches 19 that cooperate with the housing tabs 17 during assembly. When the tongue 17 is fastened in the recess 19, the housing remains spaced exactly in this area.

In the drawings and disclosure, a single power spring is shown. In alternative embodiments, there may be two or more such springs. For example, in front of the grip opening 18 of the housing 10, two coiled power springs 90 may be vertically stacked with the second mandrel 106 below the first mandrel. The pivot member 96 of this second spring engages a second tie rod hole 66 (not shown) below the first one. In this alternative embodiment, the horizontal distance between the spindle pin 107 and the hole 66 (of the two springs) is about the same as the distance between the hinge 41 and the pivot tab 45. between the same. This ensures that the pivot tab 45 and the two holes 66 remain aligned through their movement against bending. In another alternate embodiment, two power springs 90 may be mounted axially side-by-side on the common mandrel 106 . As with other disclosed embodiments, power spring 90 is pivotally attached to the housing near or in front of the front of grip 18 whereby arms 92 and 94 form torsion arms and extend from this location to striker 70 . With a relatively short torque arm, there is a lot of force available at the striker 70 for useful work, and furthermore there is minimal vibration in the action of the arm when the short arm is in operation. Longer arms can be used and mounted further back if desired. Arm 94 may be described as a first spring arm while arm 92 may be described as a second spring arm.

In Figures 1A and 13, the front cover 12 includes a bottomed raised front edge 12a. The raised portion may extend rearwardly past the striker slot 13 along the side wall of the cover 12 . In use, the stapler is often held at an angle to work with the rear end of the stand. With the clearances described herein, the striker tip 78 (FIG. 5) can still extend close to the workpiece with the front cover 12 avoided. This edge 12a may be raised, for example, by about 0.020 inches. With the lightweight reciprocating compact components described above and the tight contact therein, general staple mounting can easily produce driven staples that are flush with the work surface. Workpieces with fully loaded staples will result in tighter work and higher quality workmanship.

16 to 23 illustrate a second exemplary embodiment of the present invention. Many elements may share the first embodiment described above and the mechanical action of the power spring 90, the striker 70 and the latch 50a are or may be equal. The distance ratios mentioned when describing the first embodiment can also be used for this second embodiment. Again, the handle should be rigidly linked to the power spring in the forwardmost position and the geometry of the approximate vertical line L can be applied to this embodiment. Finally, the second exemplary embodiment reduces or can reduce parts count, friction and complexity.

In FIG. 16 , prying handle 20 of link 330 pivotably connects handle link bracket 328 to lever 340 . The lever 340 directly engages the pivot member 96 of the power spring 90 at the opening 366 . Opening 366 may be elongated to provide for longitudinal (side to side on the page) movement of power spring 90 relative to lever 340 in this position. The lever pivot 341 operates behind the spring coil 93 while the lever 340 extends forwardly through the spring coil 93 along the length of the lever to be positioned abutting the striker 70 . At hinge 333, link 330 pivots on the central lever The lever 340 is pressed towards the center of the length of the lever 340 at the axis 343 . The lever 340 is thus cantilevered forward from the central lever pivot 343 to a spring preloaded position on the pivot member 96 . In this manner, opening 366 is immediately adjacent to the pre-compression position, both laterally adjoining along pivot member 96 (go to page 16 of FIG. 16 ). At least one of spring arms 92 and 94 likewise cantilever forward from spring coil 93 whereby each of power spring 90 and lever 340 cantilever forward to a pre-compressed position. As shown in Figures 16-18, the spring arms 92, 94 are both cantilevered.

The second exemplary embodiment depicted in FIGS. 16-23 may provide further reduced friction and increased rigidity than the first exemplary embodiment of FIGS. 1-6 . While the first embodiment is substantially rigid, it can be seen from FIG. 35 that the second embodiment has one less component between the handle 20 and the power spring 90, and thus has fewer pivots or other connections to introduce flex or Gap movement. Lever 340 is also longer than lever 40 and therefore rotates about its rear pivot 341 through a smaller angle to move power spring 90 . From an empirical observation, compared to the first embodiment, the pivotability is 20 degrees, while the second embodiment has about 12 degrees. With less movement, there is less friction at the hinge of the rear pivot.

When comparing central pivots 43 and 343, each operates to a similar effect. In FIG. 18, the lever front opening 366 is rotated in the same direction as the spring pivot member 96 to reduce sliding therebetween, thereby reducing friction on the structure of FIG. 1, where the linkage rod 60 does not substantially pivot with the pivot member 96 . Regardless of whether the second embodiment of FIGS. 16-23 or the first embodiment of FIGS. 1-6 is considered, each provides substantial improvements and benefits in function and utility over the prior art, for example, through the disclosed rigid link system. According to this rigid linkage system, the front end of the lever presses the second arm at a longitudinal position substantially closer to the striker than the center of the spring arbor. As can be seen in FIG. 1 , this pressing takes place at the front end of the lever 40 , or at the front end of the lever 340 as seen in FIG. 16 .

The second embodiment of Figures 16 to 23 further enjoys simplified assembly. In FIGS. 19 and 23, the link 330 fits into the flange 332 or equivalent structure that enters the slot 329 of the handle link bracket 328 and these parts are loose and unfixed, as shown in FIGS. 20 and 21. The link bracket 328 is then secured to the handle 20 by riveting or the like, as shown in FIG. 16 . The linkage 330 is thereby pivotally constrained to the handle 20 . hem Or the top end 332 presses against the bottom surface of the handle and pivots against it, as shown in FIG. 17 . This pivot is small, about 4 degrees as shown, so friction is low and slot 329 can be narrow. When each upper and lower assembly is ready, it can be seen from Figure 18 that the handle assembly is lowered to the position shown in the figure. Linkage 330 is maintained at approximately the angle shown to align with the front wall of recess 344 . The link 330 remains out of the page of FIG. 18 and/or the lever 340 is pressed in so that the link can pass by the lever 340 to take the position of FIG. 19 . In both Figures 18 and 19, the handle 20 embodying the pivot 27 is in front of its final position. In FIGS. 21 and 22 , it can be seen that the tongue 335 of the connecting rod 330 can enter the notch 344 of the lever 340 . As can be seen in FIG. 19 , handle 20 is then moved rearwardly to its final position at pivot 27 as link 330 is rotated to be guided by edge 348 . The edge 348 then laterally locks the link 330 in the recess of the tongue 335, with respect to the side view, in a pivotal relationship on the lever. The link 330 keeps the lever 340 laterally stable through the triangular geometry "T" seen in FIG. 23 . The folded edge 332 presses the inside of the handle 20 to form a triangular stable base. The pivoting is at the link hinge 333 against the central lever pivot 343, as can be seen by comparing FIGS. 16 and 17 . The tensile connection between the handle 20 and the power spring 90 operates through the link 330 in the slot 329 and edge 348 so that the handle pulls the spring and striker in the event of a staple jam or the like.

The spring arm tip 95 is preferably central relative to the front view to compress the centerline of the striker 70, however an off-center alignment can also work. Thus, the lever 340 over-centers the spring element 96 at the pivot 366 at a location similar to that of the connecting rod 60; see Figure 4B of the first embodiment for a similar location at 66. Therefore, the lever 340 is preferably off-centered into the page of Figure 16 at the three operating pivots 341, 343 and 366 to form a stable plane of action. Segment 349 may be central, away from the page of FIG.

In FIG. 16, the latch 50a operates in the same manner as the latch 50 mentioned when disclosing the first embodiment. The rear end 53a selectively contacts the handle 20 to cause a release action. In FIG. 19 , link tab 322 supports latch bias spring 130 at coil 133 .

Fig. 24 to Fig. 34 illustrate that it is better to use the stapler in the above-mentioned first and second specific embodiments Exemplary embodiments of the staple rail and loading system also provide advantages for use with other stapler devices. The illustrated sub-assemblies provide bottom loading staples or other fasteners, as shown in Figures 31-33. As can be seen in FIG. 33 , track 180 selectively extends rearwardly to expose staple storage channel 128 . The track may extend further in that track guide tab 188 contacts stop rib 125 or equivalent structure of track chamber 120 . Preferably, the entire extension has a tab 188 at least about 4 inches behind the front cover 12 to fit a standard staple rack 405 of that length. FIG. 33 illustrates the staple rack 405 to be placed in the track chamber 120 . Rack 405 is shown approximately corresponding to half the gauge length of the partially extended track as shown.

This exemplary embodiment bottom loading system is superior to rear staple insertion systems because bottom loading allows easy access to any staples when needed. For example, it is much easier to clear staple jams or malfunctions because, as seen in Figure 33, the staple guide slots can be exposed for easy manipulation or extraction of the staples. In contrast, rear loading systems require disassembly of the track sub-assembly to access any stuck staples in front of the tool.

The construction of the present rail subassembly is suitable for use with staplers embodied in sheet metal, however it is not limited to this application. For example, it may be used in die-cast or molded embodied staplers. The preferred embodiment track subassembly includes a tightly integrated track handle 160 that is unlocked by a simple pull back, for example, to move the track 180 from the operative position of FIGS. 24 and 31 to the unlocked position of FIG. 25 . Grasping and pulling track handle 160 (FIG. 27) causes it to rotate about pivot 161 to the position of FIGS. 25 and 32A against the bias from latch spring 140 as described below. Continuing the same pulling action causes the track 180 to move to the extended position of Figure 33 while the track handle is preferably returned to the normal upright or equivalent position under the latch spring bias. Pushing the track handle 160 inwardly to the right of the view moves the track 180 to the closed working position, as shown in FIG. 31 . The track becomes locked to stay in place while the track handle remains upright or otherwise in a normal position relative to the track by a latching action.

The views of Figures 24 and 25 have the track 180 and track chamber 120 shown in longitudinal section to expose the inner workings. The locked track state can be seen in Figures 24 and 24A. Ribs 184 (see also FIG. 30 ) of track 180 engage detents 124 of track chamber 120 or equivalent structure (eg, housing 10 ). In Figure 24 and Figure 28, Spring front end 146 is secured to track bracket 181 with fulcrum 186 and centrally secured to spring loop 143 . Also refer to FIG. 33 of the fulcrum 186 . The latch spring 140 is thus cantilevered at the rear end 147 . The cantilever spring rear end 147 presses down (up in the page of the upside-down view of FIGS. 31-33 ) the track spring contact tab 126 of FIG. 24 . This is beneficial because the track 180 is thus resiliently urged upward relative to the track chamber to press the track rib 184 against the detent 124 . In this context, upwards means from the track area towards the handle in any viewing direction. Preferably, the track pull arm 167 also contacts the spring end 147 when in the fully closed track state so that the track handle does not rattle.

Pull back the track handle 160 to open the track 180 to the position of Fig. 33, Fig. 34 . It will naturally squeeze and pull it at side 166, or the leading edge in the area near component "166" of Fig. 24A. The track handle 160 is rotated around the hinge 161 to the position of Fig. 25, Fig. 25A. In FIG. 25, the arm 167 has a bias spring 140 at the end 147 upward. Pulling outward on the track 180 as indicated by the arrows in FIG. The spring 140 does not resist this downward movement because the spring is deflected away from the tab 126 by the arm 167 . As a result, track 180 clears detent 124 and is free to slide rearwardly to the FIG. 26 position, as shown.

The track handle does not require rotation to deflect the latch spring. If desired, the track can be pulled straight down to deflect the spring and clear the detent 124 before pulling out, eg, through the non-rotatable track handle interface. Although this optional structure works, it requires two steps. In contrast, the preferred track handle 160 provides an automatic cam action that automatically provides downward motion with a single step of intuitive pulling outward. These features have been confirmed in working models.

As best seen in FIG. 32A , track handle 160 is positioned laterally by arm edge 167 a within track wall portion 185 . The track handle is preferably a tightly integrated fit to the housing body, as shown in FIGS. 1 and 31 . The tool maintains a smooth profile without any track release access cavities in the back zone, eg. Rail handle 160 may comprise or include sheet metal of die-cast, plastic molded construction, or any combination thereof. In any embodiment, the staple track is still easily manipulated by the simple pulling action described above.

With the track 180 closed, the latch spring 140 is deflected by the camming action on the detent 124 and rib 184b causing the track to move downwardly towards the tab 126, following the arrow in FIG. 25B. The tab deflects the spring and moves the spring away from the arm 167 . In this manner, the track handle 160 maintains, or at least may remain, in an upright position while the operator pushes on the track handle in the normal manner. For example, if the track handle needs to be rotated outward during this movement, it will resist the operator's inward push and tend to lock the system. In contrast, the track handle remains stable, the action is intuitive and the closing operation ends with a satisfying and positive click.

The latch spring 140 in Figure 28 may be in the form of a simple wire as shown. Spring front end 146 rests on rail bracket 181 as described above. The notch 186 in Figure 33 forms a fulcrum for securing the spring turn 143, thereby preferably preloading the spring 140 in the rest state of Figure 24 so that the track handle does not rattle and the track is held securely in the closed position. in position. It can further be seen from FIGS. 24 , 25 , 25B that the latch spring 140 is slightly concave upward from the precompression so that it is in or nearly in contact with both the arm 167 and the tab 126 . The pusher spring 200 biases the staple rack pusher 400 towards the front of the rail, thereby urging the staple rack towards the striker.

Pusher spring 200 is attached to pusher 400 in a known manner. The rear end of the pusher spring 200 preferably mates to the latch spring 140 at the collar 202 as shown in FIG. 25 . To install the latch spring to the track, the track spring 140 is inserted into the collar 202 and then guided by gripping the pusher spring 200 . The latch spring 140 presses into the channel of the track 180 to deflect the cantilevered arms of the spring 140 towards each other. When the collar 143 is aligned with the notch 186, the latch spring clicks into place. This is confirmed in the working model. A pulley (FIG. 30) in recess 189 guides the forward pusher spring. Recess 189 forms an upward facing edge to support the shaft of the pulley in the track guide groove. In this way, the pulley can be mounted in the guide groove to rest on the edge of the recess 189 from above, rather than from the side.

In track 180, notches 182 provide clearance for ribs 125 as the track deflects downward, which is up on the page of the upside-down tool view of FIG. 32 . It can be seen from FIG. 32 that the retaining rib 125 has entered the notch 182 . Similar clearance is created at notch 183 (FIG. 32A) to avoid the spring contact tab when the track handle is deflected 126. As shown, notches 182 and 183 preferably include ramps on the front to guide ribs 125 and tabs 126 away from the notches as the rails move outward.

In the forwardmost position, track foot 187 contacts stop edge 123a, as shown in FIGS. 29-32 . Preferably, this contact is configured to maintain pressure at the cam contact area of rib 184 and detent 124, ie, the rear cam feature presses foot 187 against edge 123a. Track chamber tab 127a engages an opening in front cover 12 to secure the front position of the track chamber of FIG. 127a. At the back, the chamber is secured to the housing with fasteners in holes 127 . The track chamber side groove 122 guides the track foot 187 . At the rear end of the track, tab 187a is folded across the track and may be spot welded or the like to reinforce the track structure preferably. Ribs 125 and tabs 126 form part of track chamber 120 . Conversely, the rail chamber features can be formed from the structure of the housing 10, eg, housing sheet gold tabs for steel housings and the like.

Staples normally and properly fit into staple guide channels 128 located at the bottom, as shown in FIG. 33 . However, it is possible for an operator to attempt to load staples on the exposed track of FIG. 34 from above. In particular, the operator can reasonably assume that this is expected to work if the staples can enter the housing or inside the tool on the rails from here. Of course, as can be seen from Figure 26, this is not possible; the staples would be behind the propeller 400 and would not be able to reach the front of the track for use. Negative user product reviews with this flaw confirm this problem.

To cope with improper staple loading, as seen in FIG. 34, there are optional staple stoppers 16 projecting into the channels of the track 180. It is an element of housing 10, however other structures are conceivable. Again, it is physically and visually clear to the user that it is not possible to install staples from behind, and for obvious reasons. Installing in this manner is clearly inappropriate, and the user is told to "go elsewhere" for the staples after easily discovering the bottom staple guide. A housing blocking tab or track chamber may extend inwardly from one side to bear against the outer side of the track 180 in this region. This is seen as tab 16a of FIG. 34 . Preferably the stopper is visible on the outside of the tool so that staple removal is not ambiguous. In addition, Figure 34 illustrates an optional track tab 184a. Track tab 184a extends outwardly whereby the staple rack cannot fit over or pass through it. In the case of a complete 4" staple rack Next, the tab 184a makes it obviously impossible to put the staple on the track from this direction. For example a shorter rack of 2 inches could fit in the portion of the track ahead of the tongue 184a, but the combination of the tongues 184a and 16 makes placement there obviously impractical, and the message to the user is to reinforce looking elsewhere .

While particular forms of the invention have been illustrated and described, it will be obvious that various modifications can be made without departing from the spirit and scope of the invention. It is contemplated that elements from one embodiment may be combined or substituted with elements from another embodiment.

10: shell

12: front cover; cover

13: Slotted firing pin

18: Shake the mouth

20: handle

22: pivot hinge; hinge; hinge pin; link hinge; link hinge pin; pin

25: shock absorber

27: Pivot

28: Handle Link Pivot Bracket

30: connecting rod

32: Pivot

33: slotting

40: leverage

41:Hinge

43: hinge; hinge pin; central pivot

45: pivot tab; lever pivot tab

48: lock

50:Latch

54: tongue; latch tongue

55: Tongue

60: connecting rod

65: Groove

66: connecting rod hole; hole; second connecting rod hole

68: Tongue

70: striker

71: Tongue

74: Opening or edge

75: beveled surface

79: opening; striker hole; hole; spring opening

90: power spring; spring

92: spring arm

93: spring coil

94: power spring arm; spring arm; arm

95: spring arm tip; tip; powered spring arm tip

96: pivot; hinge pin; hinge element; element; pivot/support element; pivot element; support element; spring pivot element; spring element

106: mandrel

107: mandrel pin; mandrel; pin

110: hinge pin; handle hinge pin; pin; handle hinge; hinge

120: Orbit Room

129: track chamber tongue; tongue

130: Latch bias spring; reset spring

140: latch spring; deflection spring; spring; track spring

150: buffer

155: (housing) board

156: slotting; notch

157: hole

160: track handle

161: Pivot

180: staple track

181: Track bracket

190: reset spring

192: spring arm

194: outrigger

200: Propeller spring

400: Spring Driven Thruster

L: imaginary vertical line; line; vertical line; approximate vertical line

L1, L3: distance

L2: distance; short cantilever; fragment

Claims (8)

A fastening tool comprising: a housing with a top, a bottom and sides, the housing extending longitudinally between a front and a back; a fastener rail provided along the bottom of the housing; A striker on the front, which includes an upper striker position higher than the fastener guide rail and a lower striker position in front of the fastener guide rail; a power spring supported in the housing, the power spring is a torsion type , which includes a spring coil; the power spring has a first spring arm and a second spring arm, the first spring arm extending forward from the coil to a first spring end connected to the striker To move together with the striker, the second spring arm extends forwardly from the coil to a second spring end, the second spring arm compresses the first spring arm at a pre-compressed position so that the spring is in a pre-compressed position. Pressed state, the pre-compressed position is spaced ahead of the spring coil to abut the striker; a lever extending longitudinally from a rear end of a lever to a front end of a lever, the lever being accessible at a lever pivot near the rear end of the lever Pivotally attached to the housing about which the lever pivots to move vertically within the housing at the lever front end, including an upper lever front position and a lower lever front position; at a handle/housing pivot A handle pivotally attached to the housing at an axis, the handle/housing pivot at a front upper position of the housing, wherein the handle is at a position behind the handle/housing pivot at the lever a central location between the front and rear ends of the lever is attached to the lever, and wherein the front end of the lever is cantilevered forward from the central location, whereby downward depression of the handle causes the front end of the lever to move downward, and the lever front end includes a pivotable linkage connected to the second spring arm forwardly of the central location; Wherein, when in the lower position of the lever, the lever moves downward at the front end of the lever to force the second spring arm to move downward away from the first spring arm. The fastening tool according to claim 1, wherein the front end of the lever extends to a position in front of a center of the spring coil, wherein the front end of the lever is closer to the striker than the center of the spring coil. The fastening tool of claim 1, wherein the pivotable link set at the front end of the lever is vertically aligned below the handle/housing pivot. The fastening tool of claim 1, wherein the lever front end is pivotally engaged with a connecting rod, and the connecting rod is pivotally engaged with the second spring arm proximate to the pre-compression position, wherein the lever passes through the A connecting rod engages the second spring arm. The fastening tool of claim 1, wherein the preloaded position is vertically aligned below the handle/housing pivot. The fastening tool according to claim 1, wherein the preloaded position is vertically aligned to coincide above a bumper disposed in the housing. The fastening tool of claim 1, wherein a latch selectively retains the striker in the upper striker position when the handle is depressed and the power spring is deflected and energized, and wherein the latch is in The handle/housing pivot is pivotally attached, wherein the latch is pivotable relative to the handle, and the latch extends to a latch spaced rearwardly behind one of the blades of the striker The striker is engaged at the lock engagement position. The fastening tool of claim 7, wherein the striker includes a deflection between the blade of the striker and the latch engagement position, and wherein a top of the striker protrudes behind the blade to form the Latch engaged position.

Images