CN101048059B

CN101048059B - Trimmer head

Info

Publication number: CN101048059B
Application number: CN2005800366407A
Authority: CN
Inventors: 理查德·A·普罗克斯
Original assignee: Proulx Manufacturing Inc
Current assignee: Proulx Manufacturing Inc
Priority date: 2004-09-03
Filing date: 2005-09-01
Publication date: 2010-10-20
Anticipated expiration: 2025-09-01
Also published as: CN101048059A

Abstract

The invention provides a trimmer head. The trimmer head for use in a flexible line rotary trimmer including a housing adapted to be operatively connected to the trimmer to effect rotation of the head and a spool operatively connected to the housing for rotation therewith. The spool defines at least one inwardly extending line receptor channel, preferably formed by a plurality of inwardly tapered walls so as to be polygonal in cross-section. So configured, the channel walls will securely grip the cutting line upon the line being inserted in the channel and wound about the spool. To provide uniform winding of the line, a plurality of cam, cam abutment and sliding surfaces are operatively connected to the housing and spool such that when the spool is manually rotated relative to the housing in the drive direction, the spool is caused to reciprocate axially within the housing evenly distributing the line about the body of the spool.

Description

Trimmer head

Technical field

The present invention relates to a kind of at the improved trimmer head that is used for cutting the grass on a lawn, uses in the flexible wires rotation clipping device of weeds and other plant.More specifically, the present invention is intended to improve such as in U.S. Patent No. 4,458,419 and No.4, disclosed in 959,904 " collision supply with (bump-feed) " type trimmer head, and such as in U.S. Patent No. 4, the line of the head of disclosed simple manual operation more loads in 145,809.As incorporating the content of described patent at this in the following reference of passing through of setting forth fully.

Background technology

The trimmer head that is used for flexible line rotary trimmers usually carrying is wrapped in the length on the interior spool or the flexible nylon line of cut of two length, and the end of wherein said line is protruding by hole relative in the sidewall of this trimmer head.This head is installed in an end of slender axles by screw thread and by coal gas motor (gas motor) or electro-motor high speed rotating, like this, the end of line of cut extends radially out and cut off weeds or other plant from described trimmer head.When the line of cut that stretches out from trimmer head ruptures or becomes excessive wear, must cut off line of cut, and pull out new line of cut from bobbin by the outlet eye thimble in the housing side.Collision is supplied with head and is comprised that line confesses mechanism, the collision on the ground that its operation response person implements intentionally, confessing the new line of cut of measured length, usually by from being installed to that guard shield on the trimmer stretches out in the cutting above-head and will described new line of cut cutting into the length of needs with the blade of the peripheral intervals preset distance of trimmer head housing.Manual head does not comprise that any such line confesses mechanism.Must unclamp housing parts with trimmer head and remain to clamp nut on the bobbin, thereby described bobbin can separate and manually rotate with respect to described housing from described housing, to emit extra line of cut.Described bobbin and housing are fixed once more by clamp structure subsequently.

Supply with in head and the manual head in collision, the line of cut of a length or a plurality of length is wrapped on the bobbin by hand usually.Because most of cutting head adopts the line of two length of stretching out from the opposite side of cutting head, therefore must be in the winding process of bobbin carefully to avoid two strands in the bobbin to intersect or otherwise entanglement, intersection or entanglement will be disturbed emitting of ew line.Thereby supply with the head in the collision that makes described head and collision on the ground in use utilize centrifugal force to pull out the line of new length from bobbin, this point is even more important, this be because the entanglement of any line with the correct supply of interfering line.Be difficult to correctly line be loaded on the bobbin is the modal complaint of domestic consumer of flexible wires trimmer.This also is a task of losing time for the professional user.

Early stage collision feed mechanism generally includes online bobbin and gear clutch between the housing or friction clutch on every side.By the extension of collision bobbin on the ground or on other fixed object, described friction clutch separates a period of time temporarily, and the length of this section period depends on the duration of collision.Described gear clutch unclamps because of collision, engages to confess the line of a segment length relevant with the abutment of gear clutch suddenly on next opportunity then.This gear clutch has outward extending rib, and described ribbed joint closes the butt tang that extends internally, thereby when only needing to transmit a segment length, needs to rely on the collision that skill is arranged.Yet, particularly use at equipment, thereby and the bight of described rib and tang be worn in the time of no longer guaranteeing firm engagement, friction in this equipment and excessive collision usually cause confessing two or more line segments.This inevitably operation suddenly of gear clutch causes producing this wearing and tearing.

Develop a kind of like this collision subsequently and confess mechanism, it automatically confesses the line of predetermined length by each collision, and has nothing to do with the duration of colliding, and can not lose this function in continuing use.U.S. Patent No. 4,458,419 disclose this device, and are the theme with this device, and this patent documentation is incorporated this paper as a reference into.As described in detail in this patent, improved trimmer head comprises the bobbin that keeps one or more sectioned coils and simplifies the internal structure of an organization, thereby described simplifying the internal structure of an organization optionally allows the collision on bobbin response head and ground to carry out relative motion to emit the line of measured length with respect to housing.The discharging gear release mechanism of this simplification comprises that novel spring loads cam and cam slave unit, and wherein said cam follower comprises two pairs along diameter relatively and the bearing surface of inwardly facing usually, and described bearing surface is arranged round the rotation of trimmer housing.Therefore spaced apart 90 ° of described bearing surfaces, and carry by the sagging cylindrical wall of circumscribed internal chamber.Described cam member is arranged in the described chamber, be threadably engaged with the extension lower end of the driving bolt of trimmer housing, and limit two vertical adjacent cams, each cam is square configuration and limits four vertically disposed cam faces, and described cam face is suitable for engaging with bearing surface on the cam follower.Overhead cam staggers 45 ° with following cam rotation.

In operation, by the upper end of driving bolt and the connection between the trimmer drive means, housing is driven bolt and drives rotatably.Therefore described housing and cam member are driven bolt and drive, and because cam face on the cam member and the joint between the bearing surface on the cam follower, driving cam driven member and the bobbin that is installed on the cam follower again.The bobbin of lifting-line links to cam follower around the cylindrical wall setting of cam follower and by a pair of relative outwardly directed pin (stud) on the cam driven member, and wherein said pin extends in the groove that is formed in the bobbin inside.Described bobbin is provided with impinger in its lower end, be pressed towards ground or during when impinger like this with collision on the ground, described housing overcomes acting force of the spring and moves down with respect to bobbin, make down the bearing surface on the cam disengages cam follower, and allowing cam member with respect to 45 ° of cam follower rotations, the cam face of overhead cam is with the bearing surface on the butt cam follower like this.This makes the relative rotation that produces the similar number of degrees between described bobbin and the described housing.In case the active force of collision disappears, spring loads and forces bobbin and housing to return its relative position, the bearing surface of cam face and cam follower on the overhead cam is separated, and allow cam member and cam follower and make thus that bobbin is relative with housing to rotate another 45 °, thereby collide half-twist altogether at every turn, provide like this by the hole in the trimmer housing and emitted predetermined rotation relatively between required housing of the line of desired length and the bobbin.Since cam with simply, inwardly face, only be formed on cam follower surface interaction on the individual layer, therefore relieving mechanism is considered to relatively economical on making, and owing to have big abutment surface zone between cam and cam follower, so described equipment is durable, fault-free and reliable.

Owing to, have early stage difficulty in the process of some parts of 458,419 disclosed cutting heads, so the manufacturing cost of head is than the height of expection at molded patent No.4.The exploitation of new material has reduced manufacturing cost subsequently.Yet, similarly collision supply driving mechanism is developed simultaneously, a plurality of bigger square cams of formation on the top external diameter of bobbin surface and following external diameter surface wherein, and the upper and lower of the housing by surrounding described bobbin forms corresponding a plurality of cam follower.This head is in that to incorporate this paper into open in U.S. Patent No. 4,959,904 as a reference, and still producing.

In these years,, it is evident that along with from the intensified competition of manufacturer overseas, even developed new material, by patent No.4, the manufacturing of 459, the 419 early stage collision feed mechanisms that covered do not resemble yet think previously economy.Described collision feed mechanism comprises a plurality of parts, and the some of them parts must hand assembled.In addition, being threadedly engaged with and need being used by the heat that trimmer produces between vibrations, cam member and the driving bolt has dystectic chemical adhesive, gets loose out from driving bolt to prevent cam member and cam follower.Yet this adhesive has very high breakdown torque, causes to be threaded forever effectively.As a result, some parts of head can not be changed after wearing and tearing.Therefore, this head has been carried out bigger remodeling, keeping all advantages of original head, and also utilized less parts, and need not any hand assembled and need not to use chemical adhesion.This remodeling is the theme that is entitled as the unsettled U.S. Patent application of " trimmer head (trimmer head for use in flexible line rotary trimmers) that is used for flexible line rotary trimmers ", this patent was submitted on October 2nd, 2003, series number is No.10/677,700, the application is that the continuation of above-mentioned patent application is partly applied for.Collision supply of the present invention and manual head have kept all advantages of above-mentioned head and have added following function to above-mentioned head: promptly faster and more easily with the line of cut uniform winding of certain-length on bobbin and need not to increase in fact production cost.

Summary of the invention

In brief, the present invention includes a kind of improved collision supply-type rotary trimmers head, described rotary trimmers head comprises: housing, it limits the tubulose extension of sagging axial setting, described tubulose extension is suitable for the driving bolt is received in wherein, and the shape of described tubulose extension form limit with first interference engagement that drives bolt and with second interference engagement of cam member, the rotation of described like this driving bolt makes the corresponding rotation with cam member of described housing.Described cam member limits the cam of a pair of vertical adjacency, and the cross section of cam is preferably square, and each cam limits four vertically disposed cam faces, and top one in the described cam is staggered 45 ° with respect to the following rotation in described two cams.Substantially the cam follower that is cylindricality limits two pairs along diameter relatively and the abutting member of inwardly facing, and described abutting member is arranged around the central axis of described shell channel, and described cam follower is arranged near the described cam member.Described abutting member on common horizontal plane 90 ° at interval, and by the cylindrical wall carrying of extending around cam follower of cam follower.Each described abutting member limits preceding (leading) surface and (trailing) surface, back that dihedral is provided with, and described rear surface limits the cam abutment surface.Helical spring is pressed against described cam follower downwards on the described cam member, and slidably the securing member of She Zhiing engages with the extension lower end of the described cam member of the adjacency of described driving bolt lower end, described like this cam member can overcome helical spring power and vertically move with respect to described cam follower between first activation point and second activation point, in described first activation point, front cam surface on the described cam down and the back cam abutment surface planar alignment on the described cam follower, in described second activation point, front cam surface on the described overhead cam and the back cam abutment surface planar alignment on the described cam follower.

In operation, CD-ROM drive motor on the described trimmer makes described trimmer housing and described cam member rotate along first direction, because cam face on the described cam down and the back cam abutment surface on the described cam follower connect, thereby cause rotation to be passed to described cam follower.Because the engagement lugs on the described cam follower extends in the groove in the bobbin inwall, thereby causes bobbin to produce corresponding rotation.When the cutting head collides on the ground, described cam is with respect to 45 ° of described cam follower rotations, and when head breaks away from ground, produce 45 ° of rotations again, cause relative half-twist between described bobbin and the described housing like this, thereby in each collision on head and ground, all emit the new line of cut of predetermined length, and irrelevant with the duration of collision.

For ease of line of cut is loaded on the head, described bobbin is provided with the line receiver passage, described passage preferably convergent and cross section be polygon, described passage substantially radially extend in the bobbin upper flange, and is suitable for by making described bobbin rotate the outlet eye thimble of radially aiming in the housing wall with respect to described housing.When firmly pushing the receiver channel of having aimed at when the end of the line of cut that inserts certain-length by each eye thimble and with described line, described line will be firmly held in place by conduit wall when bobbin pushes back with acute angle.Therefore, by keeping described housing to maintain static, and make described bobbin along the direction rotation identical with bobbin direction of rotation in the drive pattern, can center on the line of the bobbin coiling regular length of rotation, thereby need not described bobbin to be separated from described housing in order to load line.

For the line of cut that makes described length evenly distributes around described bobbin, and prevent from bobbin, to tangle, adjacency on the described down cam and vertical thereon the rear surface of cam face and the front surface relative tilt on the abutting member on the described cam follower, keeping the fixed bobbin that makes simultaneously of described housing will cause the angled front rear surface on the cam under the butt periodically on the abutting member on the described cam follower along the driving direction rotation like this, also upwards slide thereon along described cam rear surface down, thus compression helical spring.In case described cam face has been avoided described cam abutting member, helical spring will be to the downward application of force of described cam follower, thereby described cam abutment surface and described cam are down aimed at again.The result, described bobbin will make line center on described bobbin winding with respect to the continuously manual rotation of described housing, and onlinely provide up-and-down movement or the clutch effect of bobbin with respect to described housing when being wound on the bobbin, this line-transect evenly is provided with round described bobbin.Preferably, the mark of printing is molded in the upper surface of described bobbin to allow the user to be easy to respect to the directed described bobbin of described housing, make described receiver channel radially aim at wire hole in the described housing, thereby line is easily inserted in the described receiver channel, by eye thimble so that around the bobbin loaded line.

The described line receiver passage of line loading and collision supply head configuration and the manual head that the bobbin clutch can be used for other too be convenient to of the present invention.In various situations, line receiver all be arranged on can with spool flange that the outlet eye thimble in the housing is radially aimed on.As U.S. Patent No. 4,959, disclosed collision is supplied with in the head in 904, at least the rear surface of descending the bottom radially-outer surface by bobbin on the cam follower to limit tilts, like this when keeping housing to be in fixedly installing, bobbin will cause along the rotation of driving direction that bobbin is moving along with line of cut is pulled inward to be passed eye thimble and reel and periodically clutch up and down (ratchet) in housing round bobbin, thereby the line of described length is evenly distributed around bobbin in housing.The rear surface that the preceding radial surface of following cam follower and the upper and lower by housing of cam form also can tilt, and with in the process that line is wrapped on the bobbin, provides clutch campaign more smoothly to head.

Such as U.S. Patent No. 4,145, in 809 in the disclosed manual supply head, a plurality of pins or drive projection and protrude upward around the upper surface setting of bobbin and from the upper surface of bobbin, and extend in the housing upper surface size and at interval in the corresponding hole, the rotation of housing will make the corresponding rotation of bobbin like this.By the line receiver that can radially aim at being provided in spool flange and making the housing interior upper surface inclination between each hole within it, line end can be inserted in the receiver channel and by the bobbin clamping by eye thimble, like this, described bobbin will cause the projection on the described bobbin repeatedly to move down and upwards be snapped in next hole along the inclined-plane of adjacency with respect to the rotation of described housing as mentioned above.Continuous relative rotation will cause bobbin to produce required reciprocating motion thus in housing, so that line of cut evenly distributes around bobbin.

Description of drawings

Fig. 1 is the stereogram of first embodiment of trimmer head of the present invention, wherein shows the driving bolt that trimmer head is fixed to rotary trimmers.

Fig. 2 is the exploded perspective view of the various members of the embodiment of formation trimmer head of the present invention shown in Figure 1.

Fig. 3 cuts open the sectional view of getting for trimmer head housing of the present invention along Fig. 2 center line 3-3.

Fig. 4 A is the vertical view of cam member of the present invention.

Fig. 4 B is the end view of cam member of the present invention.

Fig. 5 A is the vertical view of cam driven member of the present invention.

Fig. 5 B is the end view of cam driven member of the present invention.

Fig. 5 C is for to cut open the sectional view of getting along the line 5C-5C among Fig. 5 A.

Fig. 6 shows cam member and the cam follower vertical view at the relative positioning of its normal operating position.

Fig. 6 A is for to cut open the sectional view of getting along the line 6A-6A among Fig. 6.

Fig. 7 is the vertical view that shows the relative positioning of cam member and the online supply of cam follower position.

Fig. 8 is the vertical view that shows the relative positioning of cam member and the online winding position of cam follower.

Fig. 8 A is for to cut open the sectional view of getting along the line 8A-8A among Fig. 8.

Fig. 8 B is a cutaway view, its show one of them cam abutting member on the cam follower in the process that line is wound up on the bobbin along and moving of on the rear surface of cam down, making progress.

Fig. 9 is the cutaway view at the embodiment of the trimmer head of the present invention shown in Fig. 1-8B.

Figure 10 is the stereogram with the bobbin among the embodiment that is the trimmer head of the present invention shown in Fig. 1-9, and the part of wherein said bobbin is cut so that the structure of one of them line receiver passage to be shown.

Figure 11 A is for cuing open the sectional view of the amplification of getting along the line 11A among Figure 10.

Figure 11 B is the partial side view that shows with the amplification of the spigot surface of the port of export adjacency of line receiver passage.

Figure 11 C is the partial side view that shows in the another amplification of the line receiver channels configuration shown in Figure 11 B, wherein said line receiver passage be in respect to the preferred angle orientation of the line guiding wall of the port of export adjacency of receiver channel.

Figure 11 D be show line receiver passage with diamond cross section configuration with respect to the partial side view of the amplification of the preferred angle orientation of the guiding wall of the port of export adjacency of receiver channel.

Figure 11 E be show line receiver passage with triangular-section structure with respect to the partial side view of the amplification of the preferred angle orientation of the guiding wall of the port of export adjacency of receiver channel.

Figure 11 F be show line receiver passage with oval-shaped passageway wall structure with respect to the partial side view of the amplification of the preferred angle orientation of the guiding wall of the port of export adjacency of receiver channel.

Figure 11 G be the conduit wall structure that shows rib with respect to the partial side view of the amplification of the expectation orientation of the spigot surface of the port of export adjacency of line receiver passage.

Figure 11 H is the stereogram of the part of the particular configuration line of cut of the certain-length that can use in trimmer head of the present invention.

Figure 11 I cuts open the cutaway view of getting for the line 11I-11I along Figure 11 H.

Figure 11 J shows the partial side view that is suitable for the amplification of the spigot surface of line receiver passage that uses at the line of cut shown in Figure 11 H and Figure 11 I and adjacency.

Figure 11 K is the stereogram of the part of another particular configuration line of cut example of the certain-length that can use in trimmer head of the present invention.

Figure 11 L shows the partial side view that is suitable for the amplification of the spigot surface of line receiver passage that uses at the line of cut shown in Figure 11 K and adjacency.

Figure 12 be show trimmer head of the present invention housing section remodeling and with the sectional exploded view of the bolt that uses of remodeling housing.

Figure 13 is the cutaway view of one of them trimmer head eye thimble.

Figure 14 A is the cutaway view of bobbin, shows the inner end of the line of cut that remains on the certain-length that also centers on the bobbin winding in one of them line receiver.

Figure 14 B is the cutaway view with bobbin of intilted line receiver passage, and wherein shows the inner end of the line of cut that is maintained at the certain-length that also centers on the bobbin winding in one of them line receiver.

Figure 14 C is the partial sectional view with bobbin of single line guiding wall, and shows the line receiver passage that withdraws from adjacency and lean against the inner end of the certain-length line of cut that is pulled on the guide wall surface.

Figure 15 is the face upwarding view of bobbin, wherein shows the eye thimble alignment mark on the bobbin.

Figure 16 holds the face upwarding view of alternate embodiment of bobbin of the line of different size for adopting second pair of relative line receiver.

Figure 17 is the amplification decomposition figure of the some parts of the alternate embodiment of the housing that can use in the present invention and cam member.

Figure 18 is the exploded view of the amplification of the similar another alternate embodiment of the alternate embodiment to shown in Figure 17 of housing of the present invention and driving cam, but the member of formation interference engagement is exchanged between housing and cam member.

Figure 19 is the housing that can use in the present invention and the partial exploded view of the amplification of an alternate embodiment again of driving cam.

Figure 20 is the stereogram of second embodiment of trimmer head of the present invention from beneath.

Figure 21 is the stereogram that second embodiment of trimmer head of the present invention observes from the top.

Figure 22 is the exploded perspective view of various members that is formed in second embodiment of the trimmer head of the present invention shown in Figure 20 and 21.

Figure 23 is the plan view from above of the trimmer head housing of the second embodiment of the present invention.

Figure 24 is the face upwarding view of the trimmer head housing of the second embodiment of the present invention.

Figure 25 is for to cut open the sectional view of getting along the line 25-25 among Figure 24.

Figure 26 is the stereogram of downside of the housing of the second embodiment of the present invention, show housing upper wall inner surface and be formed on clutch inclined-plane in the housing.

Figure 27 is the cutaway view of the bobbin of second embodiment of the invention.

Figure 28 is the plan view from above of the bobbin of second embodiment of the invention.

Figure 29 is the cutaway view of second embodiment of trimmer head of the present invention, shows bobbin and trimmer head housing under drive pattern.

Figure 30 is the cutaway view of second embodiment of trimmer head of the present invention, shows bobbin and trimmer head housing under initial line winding pattern.

Figure 31 cuts open the sectional view of getting for the trimmer head bobbin of second embodiment of the invention along the line 31-31 of Figure 27, and shows by the inner end of the line of cut that twines around bobbin.

Figure 32 is the stereogram of the 3rd embodiment of trimmer head of the present invention from beneath.

Figure 33 is the stereogram that the 3rd embodiment of trimmer head of the present invention observes from the top.

Figure 34 is formed in the various members of the 3rd embodiment of the trimmer head of the present invention shown in Figure 20 and Figure 21 from the exploded perspective view of beneath.

Figure 35 is the exploded perspective view of the various members of the 3rd embodiment of formation trimmer head, and this figure is similar to Figure 34, but observes from the top.

Figure 36 is the cutaway view of the 3rd embodiment of trimmer head of the present invention, shows bobbin and trimmer head housing under on-line loaded and the collision supply model.

Figure 37 is the cutaway view of the 3rd embodiment of trimmer head of the present invention, shows bobbin and trimmer head housing under initial line loading and drive pattern.

Figure 38 is the face upwarding view on top of the housing of the third embodiment of the present invention.

Figure 39 is for to cut open the sectional view of getting along the line 39-39 among Figure 38.

Figure 40 is the plan view from above of the lower part of frame in the third embodiment of the present invention.

Figure 41 is for to cut open the sectional view of getting along the line 41-41 among Figure 40.

Figure 42 is the vertical view of bobbin of the present invention, shows down the relative positioning of cam follower with respect to the overhead cam driven member, and down cam follower and line receiver are shown in broken lines.

Figure 43 is for to cut open the sectional view of getting along the line 43-43 among Figure 42.

Figure 44 is the face upwarding view of bobbin of the 3rd embodiment of trimmer head of the present invention, shows the overhead cam driven member with respect to the relative positioning of cam follower down, and overhead cam driven member and line receiver are shown in broken lines.

Embodiment

Now will be in detail with reference to the accompanying drawings, figure 1 illustrates first embodiment of collision supply-type trimmer head 10 of the present invention, wherein said trimmer head 10 is installed on the elongated end of the rotatable drive shaft 12 on fuel oil actuating or the electronic rotary trimmers (not shown).Described trimmer head 10 generally comprises: housing 14, the bobbin 16 that is used to load the coiling filament nylon line of cut 17 of one or more length, cam member 18, cam follower 20, helical spring 22, drive bolt 24 and locking nut 25.Described trimmer housing 14 preferably forms by injection molding nylon 6 copolymers, and trimmer housing 14 limits circular top wall 26, the sagging skirt section 28 of tubular and the tubulose extension 30 that is provided with placed in the middle, described tubulose extension 30 round the centre rotational axis line " Y " of head from the 26 sagging inside that enter housing, upper shell surface.Described tubulose extension 30 in the trimmer head housing 14 is defined for the outer shoulder 32 of annular and the axial passage 34 of helical spring 22, and described driving bolt 24 extends by axial passage 34.Passage 34 is constructed to driving bolt 24 and cam member 18 forms mating component.The cross section of the upper end 36 of passage 34 is preferably square; The constant-radius at middle part 38 and the cross section of bottom 40 are hexagon.

As Fig. 2 and shown in Figure 9, drive bolt 24 and limit: square head portion 24a, described square head portion 24a are accommodated in the top 36 of relative configurations of passage 34; The 24b of cylindrical body portion, it extends through the tube portion 38 of central authorities of passage 34; And lower shaft portion 24c, it stretches out and extends through the following hexagonal portion 40 of passage 34 and stretch out from following hexagonal portion 40 from the bigger body 24b of diameter.Drive bolt and also define internal thread cylindrical 24d, it extends axially the entity part by head 24a and middle part 24b, is threadedly engaged with the driving shaft 12 with trimmer.Therefore, be arranged in the passage 34 and and be threadedly engaged with by driving bolt 24 with driving shaft 12, because the interference engagement between the top 36 of the passage 34 that drives the square head portion 24a of bolt and is limited by housing extension 30, the rotation of driving shaft causes driving bolt 24 and housing 14 corresponding rotations.

Should be noted that the head that drives bolt and axially the cross section on the top of sagging tubular element can form other shape beyond square, to form the interference engagement of expectation.For example, thus the rotation of their can all to be hexagon drive bolts still can be delivered to trimmer head.

Molded the forming of nylon 6 material that cam member 18 is preferably strengthened by glass, cam member 18 has the structure of monomer, and limits in a preferred embodiment: hex-shaped head 42, overhead cam 44, following cam 46 and skirt end 48.In the bottom 40 that is sized and shaped as the passage 34 that can be received in the extension 30 of head 42, the counter clockwise direction of housing 14 (when observing from the top, in Fig. 6 and Fig. 7 with shown in the arrow D) rotation will be transmitted corresponding rotation to cam member 18 like this.In a preferred embodiment, the cross section of the bottom 40 of the head 42 of cam member 18 and passage 34 is a hexagon.Yet should be appreciated that the shape that also can use other non-circular (for example, square) realizes the interference engagement of expecting between tubulose extension 30 in the housing and the cam member.

In the alternate embodiment of housing and cam member, the cross section of the bottom 40A of the head 42A of cam member 18A and the tubulose extension 30A among the housing 14A is a tubular, and a plurality of ribs of vertically stretching out by the elongated end 47A from tubulose extension 30A shown in Figure 17 of the interference engagement between housing and the cam member or lug 45A and the corresponding a plurality of receiving slits that form among the upper surface 51A of cam 44A or hole 49A provide.Though need right rib and groove or lug and the hole of at least one composition, relatively rotate between housing and the cam member preventing, yet more preferably adopt more groups, from making and the angle of operation, it seems that four pairs of ribs of uniformly-spaced arranging and groove or lug and hole be preferred.This structure is shown in Figure 17.The elongated end 47A that the male member (for example, rib or lug) that should be appreciated that this interference engagement can be set up tubular shell extension 30A shown in Figure 17 goes up or is set on the upper surface 51A of cam 44A.Under any situation, corresponding female member (for example, groove or hole) can be set in another parts.What figure 18 illustrates parts thisly exchanges setting.In another alternate embodiment, the head of cam member can be fully phased out, and required interference engagement provides with receiving slit or hole 47A ' by identical or similar a plurality of rib or flange 45A '.This variation is shown in Figure 19.Male member and female member can be exchanged equally, accordingly.

Overhead cam 44 and following cam 46 preferably are square configuration, with limit on each cam four same vertically disposed surperficial 44 ' and surperficial 46 '.When cam D (when observing) when rotation in the counterclockwise direction from the top, each these surface in abutting connection with cam 44 or cam 46 one of them the cam driving side or the part at the angle on the front side limit cam face 44a or 46a.Each cam face on each cam is parallel with the rotation Y of head.As shown in Fig. 4 A, overhead cam 44 rotates with following cam 46 and staggers 45 °.As shown in Fig. 2 and Fig. 4 B, following cam face 46 ' perpendicular to and be inclined upwardly and limit slidingsurface 46b in abutting connection with the part (therefore when cam member 18 was rotated counterclockwise, described part was positioned on the trailing flank of cam 46) of cam face 46a.Slidingsurface 46b can form by linear surface or the curvilinear surface that tilts.In the shown embodiments of the invention of Fig. 1-9, slidingsurface is preferably and is cut into fillet.As an example, in cam member 18, overhead cam 44 and following cam 46 respectively limit the surface 44 that length is about 0.90 inch ' and 46 ', and the thickness of time cam 46 is about 0.20 inch.It is 0.125 inch circular segment that inclination on the back slidingsurface 46b defines radius.Alternatively, surperficial 46b can tilt with about 25 degree angles.

Cam member 18 also limits the passage 50 that axially is provided with, and described passage vertically extends through cam member.Passage 50 have be suitable for holding the first constant radius part 24b that drives bolt 24 first on constant radius part 50a and be suitable for holding the second less constant radius part 50b of diameter of second (less) constant radius part 24c that drives bolt 24 with sliding matching mode, the driving bolt extends through passage.

Cam member 18 is arranged on the inside of the cam follower 20 in the trimmer head 10, and structure the best of this cam follower is shown in Fig. 5 A and Fig. 5 B.In order to make the correct lines outlet eye thimbles of aiming in the trimmer head housings 78 of cam member 18, with key (key) 42 ' the be molded into side of the head 42 of cam member, described key be received in groove 40 in the bottom 40 of central shell channel 34 ' in.

Cam follower 20 is preferably by molded with cam member 18 identical materials, it is a monomer structure, and limit cylindrical wall portion 52 and four projectioies that equal angles is provided with of external chamber 54, described projection limits the abutting member 56 of radially extending to the inboard of chamber 54 from the last inner end of cylindrical wall 52.Each abutting member 56 qualification is the cam bearing surface 56a of angle setting and the slidingsurface 56b of inclination.Between member 56, be provided with deactuate zone (relief area) 60.Bearing surface 56a is positioned at the rear side of each abutting member, is parallel to the rotation Y that cuts head and extends, and become 135 ° angle with respect to adjacent slidingsurface 56b.For bobbin 16 is fixed on the cam follower separably, round cylindrical wall portion 52 equal angles of cam follower 20 a plurality of outwardly directed radial lobes 62 (showing four) are set.

Upper, annular flange 70 and lower annular flange 72 that bobbin 16 limits by 74 carryings of hollow barrel-type body part, to limit the annular region 76 between the

flange

72 and 74, described annular region is used to load the coil around the flexible nylon line of cut 17 of body part 74 windings, like this, when assembling, the end 17 of line of cut ' pass eye thimble 78 to stretch out, described eye thimble are press-fitted by the relative hole 80 in the sidewall that is formed by shell skirt 28 of head.In the preferred head configuration shown in Figure 1, shell skirt 28 raises or radially outward-dippingly invades and harasses in use to protect eye thimble to avoid foreign matter in abutting connection with the part of eye thimble 78.

The body part 74 of bobbin 16 further limits: be arranged in the body part lower end circular impinger 81, inner cylindrical chamber 82, be positioned at body part madial wall a pair of along diameter relatively and construct identical vertical locking channel 84 with a pair of along diameter relatively and construct identical vertical guide channel 88, described guide channel is transversely arranged with respect to locking channel 84.As shown in Figure 10, locking channel 84 ends at slightly shallow offset portion 90 in the lower end, and described offset portion 90 ends in a pair of hole 92 that is relatively fixed, and described fixing hole extends through cylindrical body part 74.Each locking channel and guide channel all are suitable for receiving slidably an outwards outstanding radial lobes 62 on the cam follower 20.Described guide channel 88 is that with the difference of locking channel 84 guide channel is wideer, consistent length and do not end at the hole.Preferably, the width of the described guide channel width that equals locking channel adds the length of the offset portion 90 of locking channel 84.

When lug 62 is punctual with locking

channel

84 and 88 pairs of guide channels, bobbin 16 is fixed to cam follower 20, like this, the end 17 of line of cut 17 ' extend radially out from bobbin 16 near eye thimble 78, bobbin is crushed on the cam follower, arrives the lower end of guide channel and locking channel up to lug 62.Described bobbin rotates subsequently, lug in two locking channels 84 enters the slightly shallow offset portion 90 of locking channel like this, bobbin compress slightly cam follower arrives hole 92 up to described two lugs, like this, the elasticity of cam follower material causes lug to buckle into hole 92, thereby bobbin is fixed to cam follower.In latched position, two lugs in the hole 92 are placed in abutting connection with hole wall, and the antetheca of two lug adjacent channels in the guide channel 88, so in use, four lugs will be all near its abuts with wall, to realize the corresponding rotation of bobbin 16 along with cam follower 20.In order to take off bobbin, only need to reverse bobbin, and when lug is drawn rearward into the vertical component effect of locking channel, can easily from housing, take out described bobbin vertically with respect to cam follower.

The structure of above-mentioned lug and passage allows bobbin 16 is used together with the cam follower that has four equally spaced driving lugs 62 (as shown in the figure) or have two relative lugs in case of necessity.In addition, driving force is evenly distributed between four lugs 62 on the cam follower 20.Guide channel 88 is set, and to substitute second pair of locking channel 84 only be for molded and shaped purpose.Otherwise can adopt four identical locking channels.When needing, two guide channels in the bobbin can be widened, and make each guide channel limit about 95 ° of arc length, and bobbin can receive the cam follower structure with six lugs that equidistantly stretch out like this.In addition, the size of guide channel can be decided to be the antetheca of two lug adjacent channels in each guide channel, so in use, four lugs will play the work of driving lug once more in order to realize the rotation of bobbin.

For the quick loading of trimmer line around bobbin 16 is provided, bobbin upper flange 70 is provided with a pair of relative line receiver 91, is used for the inner end 17 of two independent length of clamping line of cut 17 ".Each receiver 91 comprises line receiver passage 93, and it opens portion 93 ' the extend radially inwardly to cylindrical body part 74 of bobbin from the expansion of adjacency bobbin outer rim outer.As will be descr, receiver channel 93 structure and be oriented to that the eye thimble that passes through to be aimed at when the end of line of cut inserts in the receiver channel and by when bobbin pulls back with acute angle, tightly the clamping line of cut 17.The example of passage 93 at length illustrates in Figure 11 A-Figure 11 G, Figure 11 J, Figure 11 L, Figure 14 A and Figure 14 B.The cross section of preferred channels configuration is a polygon, and most preferred be hexagon, and from the portion of opening 93 of expansion ' to body part 74 with convergent in about 5 ° angle.The size of described receiver channel depends on and will be fixed to the size of line wherein.By make the inside convergent of conduit wall with about 5 ° angle, described passage can adapt to the variation of linear dimension.

As an example, in trimmer head 10, successfully adopted such tapered channels 93, its cross section is that hexagon and length (remove the portion of opening 93 ') are about 0.650 inch, lateral dimension between two parallel side of the open port of export of adjacency expansion records and is about 0.130 inch, and is about 0.075 inch (for example referring to Figure 11 A) across the lateral dimension of internal channel end.Diameter is that the conventional nylon line of cut of 0.080 inch, 0.095 inch and 0.105 inch can be received in the trimmer head, and when shown in Figure 14 A and Figure 14 B, when twining line of cut, can pass through receiver channel wall clamping line of cut tightly from the outer end draw cut secant of passage and around bobbin.

After line of cut comes out from receiver channel, in order inwardly to guide line of cut rightly, the portion of opening 93 of the expansion of each receiver 91 ' downstream or left side cut to be limited to flat guiding wall 94a and the 94b shown in Figure 11 B and Figure 13-Figure 15.94a is vertical substantially and downward-sloping slightly with the central axis of receiver channel on the surface, and like this, it is oblique that the central longitudinal axis " X " of guiding wall limits about 5 °-10 ° angle lapping with respect to horizontal line, and this angle depends on the structure of bobbin.Adjacent surface 94b slopes inwardly with the central authorities of bobbin that line is led.Therefore, when line of cut is inserted in the receiver channel 93, and against spigot surface 94a laterally and when spigot surface 94b inwardly spurs, line and centre gangway axis form an acute angle effectively.In addition, the interior lower surface 95 of the flange that extends below passage 93 be circular, to avoid having any unexpected surperficial potential difference and will be towards lower flange 72 guiding under the alignment, the correct winding of this potential difference meeting interference line at abutment line receiver 91 on the bobbin.The passage 93 preferred relative bights that are orientated passage around its central axis are aimed at the central axis X of guiding wall 94a, shown in Figure 11 C.

By relative passage bight is aimed at the central axis " X " of guiding wall 94a, when from passage and along the guiding wall 94a pulls wire of adjacency, the conduit wall cramping that line of cut is retracted.Because the intensity of nylon line of cut inherence, this cramping of line of cut is not occurred over just conduit wall bight 93 in abutting connection with spigot surface 94a " (referring to Figure 11 C), and occur in the place, relative bight at the place, the inner of line receiver passage, thus strengthen clamping to line.Although the line receiver passage have as mentioned above with the hexagonal cross section (for example referring to Figure 11 B) that is configured to of the central axis misalignment of surperficial 94a still can the described line of clamping, but the nip effect that the aligning shown in Figure 11 C has utilized the passage by hexagonal cross-section structure to create better, thereby be preferred.And, slope inwardly about 5 ° by the central axis that makes receiver channel 93 as shown in Figure 14B to guide wall 94a, rather than the central axis of passage and the center of bobbin are radially aimed at, described central passage axis is with respect to the port of export and tangent linear the acutangulating of flange at passage.As a result, when line of cut comes out also to be spurred by the guiding wall 94b against adjacency from receiver channel, can make line of cut form acute angle immediately with respect to the centre gangway axis.This has further increased the nip effect of conduit wall to line, and then has strengthened the grip to line of cut.Receiver channel is firm more to the clamping of line, and the user is easy to realize the initial winding of wire-wound bobbin more, and can not pull out line unintentionally from the line receiver passage.Yet the acute angle that forms in abutting connection with the port of export of receiver channel by the central axis of the passage that slopes inwardly as mentioned above may be that 0.105 inch line is too tight to diameter.Therefore, in the trimmer head of the line that is designed to hold this large-size, the passage of radial directed is preferred.

Other line receiver channels configuration has been shown in Figure 11 D-Figure 11 G.Figure 11 D and Figure 11 E illustrate and are particularly suited for other polygonal structure that the present invention uses.Figure 11 D shows the line receiver passage 93a with lozenge shape cross-section.Press the effect maximum for the wire clamp that makes this passage, described passage should be oriented as shown in FIG., and the relative angle portion that is positioned on the cross section minor axis is positioned on the longitudinal axis " X " of guiding wall.Figure 11 E illustrates the line receiver passage 93b with triangular cross section.Press the effect maximum for the wire clamp that makes this channel design, be positioned on the leg-of-mutton summit that its port of export limits on the longitudinal axis of guiding wall, in abutting connection with described guiding wall, shown in Figure 11 E by passage.Other polygon cross-sectional configurations also can adopt when forming line receiver passage 93 of the present invention.Yet, it has been generally acknowledged that, will enough justify by the passage that forms more than about eight sidewalls, to such an extent as to can not provide desirable chucking power to line.Have been found that circular radial passage provides the enough clampings to line in the time of can not being positioned on the longitudinal axis of guiding wall in described square flat side as the passage that limits the square cross section structure.Also can adopt other channel design.For example, shown in Figure 11 F, the line receiver passage 93c (wherein Tuo Yuan minor axis is positioned on the longitudinal axis of guide wall surface channel) with ellipsoidal structure will provide enough chucking powers to line.Also can utilize the irregularity in the channel wall.For example, Figure 11 G shows such line receiver channel design, wherein a plurality of, as to be preferably four longitudinal extensions ribs 93 " ' be arranged on otherwise on the circular conduit wall with the clamping line.In order to prevent that rib and/or line are produced excessive wear, described rib is preferably spaced apart, like this shown in Figure 11 G, described line will be at the inner of passage and place, outer end equally against two ribs wherein.Other this irregularities in the sidewall of receiver channel can comprise rough surface and extend spirally the rib (not shown) on passage.

Although the above-mentioned line receiver channel design of describing and illustrating is extended along the whole length of passage, and such structure is preferred really, yet should be noted that the clamping feature of passage need not the length of extending channel.Can hold cross-sectional structure and obtain acceptable wire clamp to be held by wire clamp only is set in the outer end of passage.For instance, the cross section of the outer end of passage can be hexagon or rhombus, and the remainder of passage can be circle.When line from passage and against adjacency spigot surface 94a side draw and subsequently when face 94b inwardly spurs, described line can be retained in the receiver channel by the pinch wall in the outer end of passage.The length of the described passage outer end of this structure should be at least about 0.150 inch.When the line receiver passage that utilizes convergent received the line of multiple size, only wired inside needed convergent.Preferably, in this channel design, the passage axial length at least about 50 percent (should convergent except opening part 93 ").

Except thereby the cross section of the outside of line receiver passage keeps the such as mentioned above clamping line of cut in end of line of cut by constructing at least, described passage can be constructed to cooperate to realize fixing of line by fit effect or embedding effect when line twines around bobbin with specific line structure.For example, Proulx Manufacturing by California, USA Lan Qiaokukamengjia, Inc. company's flexible and denoising trimmer line that sell, that name is called Ultra Quiet is by pushing two non-thread polymer line thighs in the mode of sealing processing (close disposition), thereby and in cooling bay described two line thighs formed round the longitudinal axis wringing together.After the curing, formed line limits the columnar alignment thigh of two overlappings, and described line thigh links together in the cell body (trough) of two relative basic forming V-shapes, and described cell body extends spirally along line and around line.Compare with the conventional line of the comparable size of rotating under the identical speed, when rotating with identical speed, find that this line structure can reduce noise to a great extent, the series number that this line is configured to submit August 29 calendar year 2001 is No.09/942, the theme of 248 unsettled U.S. Patent application.The example of this noise reduction trimmer line 517 shown in Figure 11 H and its cross-sectional configurations shown in Figure 11 J.By structural line receiver channel 593 (referring to Figure 11 J) to have the respective cross section of extending along the external helicoid of passage at least, when the outlet opening of line by the aligning in shell skirt is inserted in the described passage and rotates, conduit wall will cooperate with line, and effectively with passage in line can engage spirally, and the end of line is fixed to bobbin.

Another example of band key (keyed) line and receiver channel has been shown in Figure 11 K and Figure 11 L.As this illustrate, be provided with outstanding locking component 617a near the online end of the line of cut of certain-length 617.Member 617a can be any structure easily.At least the end of line receiver passage 693 (referring to Figure 11 L) correspondingly is configured to receive the line with protruding member, and the passage area that is provided with skew in passage is to allow the line rotation.Described like this protruding member is received in the described offset area.Therefore, when with the outer end of member 617a and receiver channel 693 on time, insert and the described line of wringing, the line of described certain-length is fixed to bobbin by jammed locking component, can twine described line around bobbin as mentioned above like this.In all such embodiment, the circular hole in the eye thimble 78 in the side of described trimmer housing is far longer than the diameter of line of cut, thus locking component can interference line extension by eye thimble.

Figure 14 C shows the line receiver of another kind of remodeling, and described line receiver adopts single, intilted guiding wall 94c, and described guiding wall 94c is arranged near the port of export of receiver channel.Be similar to the passage 17 that slopes inwardly shown in Figure 14 B " described single, intilted guiding wall 94c between the spigot surface of the central axis of receiver channel and adjacent channel outlet, produce an acute angle.Because compare with comprising the aforementioned spigot surface that extends laterally 94a of portion and rake 94b, this single spigot surface 94a will be directed to the center of bobbin quickly in the alignment, and the speed that the big bobbin of bobbin diameter group that diameter is more little pumps is fast more, so single spigot surface 94c preferably uses in less head.Because less bobbin generally can not be designed to receive larger-diameter line, so the sharp bend that spigot surface 94c produces generally can not brought problem.

In each remodeling of above-mentioned line receiver, the winding process of line is identical substantially.For line of cut being wrapped on the bobbin 16, the eye thimble 78 that the line receiver passage 93 in the bobbin is aimed in housing 14 sides.Preferably be provided with such as the marking of arrow 85 at the lower surface of bobbin so that aim at, as shown in figure 15.Then, the inner end 17 with the line of cut 17 of two independent length " inserts and pushes reliably the receiver channel of aiming in the spool flange 70 93 by eye thimble relative in the housing 78.In line shown in Figure 11 J-Figure 11 L and channel design, as mentioned above, described line must be by wringing together.Then, the line of described length is with sharp bend and pasting side direction guide wall 94 by to 74 pullings of spool body part.Next, when keeping housing to be in static setting, use impinger 81 as handle rotating bobbin manually in the counterclockwise direction.The wall that the preferred convergent of qualification receiver channel and dihedral are provided with is the inner of clamping line of cut tightly, prevents that the inner of described line from withdrawing from passage.When bobbin continues to rotate in the counterclockwise direction, the line of cut of described two length will twine around bobbin.

The manual rotation in the counterclockwise direction of the relative housing 14 of bobbin also will make cam follower 20 relative cam member 18 corresponding rotations, the slidingsurface 46b butt (seeing Fig. 8 A) of the opposing inclined on slidingsurface 56b that makes in the inclination on the abutting member 56 and the following cam 46.Because surperficial 56b and surperficial 46b tilt along relative direction, when keeping housing static, continue to be rotated counterclockwise bobbin abutting member 56 on the cam follower will be pressed onto on the slidingsurface 46b on the cam 46 down in the above.When cam follower 20 relative cutting head shells 14 moved up, bobbin 16 also moved up.This moving shown in Fig. 8 B.When back bight (trailing corner) that cam follower 20 rotates to down cam 46 during with position that the deactuate zone 60 in the cam follower is aimed at, thereby cam follower also has bobbin 16 will snap into their downwards relatively and initial height of housing under the active force of helical spring 22, wherein aims at cam bearing surface 56a on cam follower at the cam face 46a on the cam member.Therefore, when the line of cut of described two length is pulled inward moving by eye thimble 78 and twines around bobbin, the manual rotation of the relative housing of bobbin continuation in the counterclockwise direction will realize bobbin constantly vertical clutch or reciprocating motion in housing.

When the line of described two length enters spool areas from the opposite side of bobbin, and the port of export by line receiver is when leading the center of bobbin respectively, even less than the distance between upper bobbin flange 70 and the lower spool flange 72, this reciprocating motion of rotating bobbin also can make line of cut center on bobbin evenly to distribute bobbin relative to vertical distance that housing moves.As a result, the line of described length will be reeled voluntarily and be filled bobbin, and can not tangle on bobbin.

More than description that trimmer head 10 and parts thereof are carried out based on the rotary trimmers of routine, using described head, in described trimmer, the gear-box (not shown) usually will counterclockwise rotation be passed to driving shaft 12 and also be passed to trimmer head thus.If described head is at the trimmer that does not have gear-box or have on the trimmer that makes the gear-box that head clockwise rotates and use, front surface on the cam and rear surface and cam follower abutting member only will be exchanged.Therefore, only need make cam and down on the cam and the orientation of the slidingsurface on the abutting member 56 of cam follower 20 exchange.Cam face 46a on the following cam will be still the front surface 46 of cam 46 ' on, and slidingsurface 46b is on rear side.Similarly, cam abutment surface 56a will be still on the trailing flank of each abutting member, and slidingsurface 56b will be still on the front side.

Comprise under the situation of two line receivers relative 91 at the bobbin 16 of describing and illustrating along diameter, if only need the head of single line, then can adopt such receiver, perhaps alternatively, can use a plurality of receivers of equidistant apart.And, can adopt the relative receiver of two couples of different size to provide additional multifunctionality to the cutting head.For example,, can adopt second pair of bigger line receiver of cross sectional dimensions except shown and at above-described receiver in the accompanying drawings, wherein each to relative receiver with another to vertical so that the head balance.By this structure, the size of a pair of relative receiver is confirmed as holding the line of cut of minor diameter, as the line of 0.065 inch, 0.080 inch and 0.095 inch, and second pair of receiver can hold the bigger line of diameter, as 0.095 inch, 0.105 inch and 0.130 inch.For such application, should on the upper surface of bobbin, print second pair of mark and aim at, and which indicate receiver is held the line of large-size to help second pair of line receiver and line outlet eye thimble, which holds the line of reduced size to receiver." the vertical setting is with the size of identification passage and aim at the line of cut of described length for for example, a pair of relative layer arrow 85 of a pair of less or narrower arrow 85 ' can be relatively as shown in figure 16.

Fully assembling and load line of cut after, cam member 18 is arranged in the chamber 54 of cam follower 20, hexagonal head 42 of cam member 18 is arranged in the relative configurations part 40 of the passage 34 that the tubulose extension 30 by housing limits.Helical spring 22 is arranged between the shoulder 32 and the upper surface by cylindrical wall 52 and projection 56 cam followers that limit 20 that is formed by housing extension 30, and against described shoulder and described upper surface, thereby press down cam follower 20 around cam member 18, make the upper surface in following skirt section 48 around cam member of abutting member 56 on the cam follower.The pushing-type fixator (push retainer) of 5/16 inch or other suitable dimension or locking nut (pal nut) 25 (being also referred to as pushing-type nut or bolt device) slide on the cylindricality lower end of the axial region 24c that drives bolt 24, are closely pasting skirt section 48 downsides on the cam member 18.The axial region 24c that drives bolt can be that be threaded or smooth, such as shown in the 2982nd page of 2003 editions the McMaster-Carr catalogue and the pushing-type fixator of describing be applicable to screw bolt or non-threaded bolt.By screw thread being set,, can adopt conventional screw thread hex nut at the scene in the maintenance if in case of necessity and do not have the pushing-type fixator at the axial region 24c that drives bolt.Yet, use the pushing-type fixator can make the assembling simplification and the full automation of the head 10 of trimmer, this also is a purpose of the present invention.

Bobbin 16 is arranged on the inside of housing 14, and two lugs 62 on the bobbin 16 are placed in the offset portion of locking

channel

82, and 92 is outstanding from the hole, and remaining two lugs are placed on the bottom of two guide channels 88.Impinger 81 on bobbin 16 bottoms stretches out from the lower ends downward of housing 14, and as shown in Figure 1, and the relative eye thimble 78 that the elongated end of line of cut 17 is passed in the shell skirt 28 stretches out.

The eye thimble 78 that the present invention preferably adopts is made of the aluminium of airborne vehicle grade, and each eye thimble is all located in their the inners to limit the holding flange 100 of annular and be used to that line of cut is passed wherein to reach the radially path 10 2 of extension that enters receiver 91.As shown in figure 13, the inner end 104 of path 10 2 and outer end 106 form fillet eliminating any wedge angle and to hold line around the bending of eye thimble, and can not make the bent or excessive pressurized of the coil of wire.This eye thimble structure makes eye thimble 78 be attached to head 10 and in use by flange 100 and the centrifugal force maintenance that produces in position thereon in the process of automation.

In operation, because the assembling between the tubulose extension 30 of driving bolt 24, driving shaft 12 and housing 14, so the rotating driveshaft on the trimmer 12 makes housing 14 and cam member 18 produce corresponding rotation.Cam follower 20 is pressed downward with respect to cam member 18, thereby the skirt section 48 of the following butt cam member 18 of the projection on the cam follower 56, and the cam face 46a on the following cam 46 aims at the abutment surface 56 that is limited by the abutting member on the cam follower 20 56 and leans against on the described abutment surface 56, be rotated counterclockwise accordingly thereby make cam follower and produce by the bobbin that described cam follower loads, as above seen in Figure 6.The vertical length in the skirt section 48 by making cam member 18 is about 0.5 inch, rather than adopts thinner dish structure, can minimize use cam member rocking in cam follower.

Rotary collision device 81 on bobbin 16 bottoms is pressed to after ground or other rigid surface, press down trimmer housing 14 and be driven bolt 24 and fixator 25 is fixed to the cam member 18 of trimmer housing, compression helical spring 22 and the abutment surface 56a that cam 46 is broken away from the cam followers.When cam member 18 moves down upper surface up to the lower end of tubulose extension 30 30 ' butt overhead cam 44, following cam from path that cam abutment surface on the cam follower engages come out, and the cam face 44a on the overhead cam 44 is sent into the path of cam abutment surface 56a.This slows down the rotation of cam follower 20 relative cam members 18, and the rotation of bobbin 16 relative cam members 18 and housing 14 is slowed down.When the 44a bump abutment surface 56a of overhead cam surface, the corresponding rotation of cam and cam follower restarts (see figure 7).Yet during this period, the rotation of relative cam follower with housing of cam member and bobbin is 45 °.

In case the active force of collision disappears, helical spring 22 makes bobbin and housing return its initial position, cam face 44a on the release overhead cam 44 engages with the abutment surface 56a's of cam follower, engage cam surfaces 46a once more, thereby make cam member also make another 45 ° of the relative rotation of bobbin with housing with cam follower, thereby no matter the time that collision continues how, all makes and rotate 90 ° altogether in collision process.During rotating relatively, bobbin lags behind with respect to housing, and centrifugal force causes emitting by eye thimble relative in the trimmer housing 78 the new line of cut of scheduled volume.Next, that load by the protectiveness cover (not shown) that is installed in trimmer top and cut off the line that has worn and torn with conventional cutting blade (not shown) that rotation head 10 is radially spaced.

It should be noted that, cam follower 20 is included in the deactuate zone 60 between the projection 56, thereby when cam 44 and cam 46 are in line and supply with the position with respect to cam follower as shown in Figure 6 and Figure 7, cam 44 can slide by relative cam follower 20 vertically with cam 46, and allows bobbin in the process of loaded line and do not move back and forth in other time.In position as shown in Figure 7, cam 44 and cam 46 can upwards slide and break away from cam face 44a, and in Fig. 6, can break away from cam face 46a to lower slider.Cam with three or more or heteroid cam face also is feasible, and the cam 44 and 46 with four sides is the practical compromise proposals between surf zone contact site, workability and desirable line are confessed.And, as to limiting cam and substituting in abutting connection with the square cam of the slidingsurface in this cam bight, the sidewall that the overhead cam that staggers on the angle and following cam all can have four indents, and at the radial protrusion or the tang of four equidistant intervals of four bights place's qualification.Like this, the leading edge and the trailing edge of described tang will limit described cam and slidingsurface.This cam member need not to change cam follower 18 and just can move.

In the preferred embodiment of cutting head shell 14, thereby in shell skirt 28, be provided with " window " that indent zone 99 is formed for label.By thereon with the surface 99 of adhesive label ' depart from the remainder of shell skirt, thereby in use described labeling is protected.

Housing that can use in the present invention and the alternate embodiments that drives bolt have been shown among Figure 12.These embodiment are with the difference of previous embodiment, upwards promote to drive bolt 124 and enter the bottom hexagonal part 140 of inner shell extension 130 to assemble.The hexagon bottom 140 that the tubulose extension 130 of remodeling housing 114 limits tubular top 136 and extends, this tubular top 136 has around the annular ridge 137 of the rising of its internal side wall extension.Driving bolt 124 limits: tubular top 124a, described top 124a have the annular groove 124e that forms therein; Hexagon middle part 124b; And the cylindricality axial region 124c that reduces of diameter, described axial region 124c is the same with the axial region 24c that drives bolt 24 to have screw thread or smooth.After described driving bolt 124 insertion tubulose extensions 130, the spine 137 in the bolt top provides interference engagement so that bolt is remained in the housing.If immediately bolt is pushed correct position after described housing forms, then nylon material will shrink around bolt when cooling, thereby strengthen fixing.Yet even just bolt is inserted the housing extension after housing forms and cools off for a long time, the engaging between bolt and the housing extension also can remain on the appropriate location with bolt.

The tubular top 124a that drives bolt 124 has and extends axially by tubular top 124a and extend to the threaded cylindrical hole 124d of hexagonal part 124b, is used for being threadedly engaged with the driving shaft 12 of trimmer, and this was with before embodiment was identical.Yet in case of necessity, bolt 124 can be provided with threaded extension (not shown), to be suitable for engaging the trimmer drive axle with the recessed end of screw thread.Identical variation also is applicable to certainly and drives bolt 24.The hexagonal part 124b of described driving bolt is received in the top of hexagonal part 140 of housing extension 130, and after cam member 18 and cam follower 20 were fixing, described hexagonal part 124b just was arranged to tightly the hex-shaped head 42 in abutting connection with cam member.As among the embodiment formerly, the axial region 124c that drives bolt 124 stretches out downwards and exceeds the end of housing extension 130 and be used to engage pushing-type fixator 25 by cam member 18.Remaining element also counter element with previous embodiment is identical.The same with previous embodiment, this embodiment can assemble with fully automatic process, and uses minimum parts, does not need the chemical adhesion spare to thermo-responsive and/or obstruction part replacement.

The second embodiment of the present invention such as Figure 20 are wherein manually using the line load maintainer in the trimmer head 100 to shown in Figure 31.It is on the elongated end of the rotatable drive shaft on power or the electronic rotary trimmers that head 100 also is installed in gasoline.Described trimmer head 100 generally comprises housing 114, be used to load the bobbin 116 of filament nylon line of cut 17 of the coiling of one or more length, helical spring 122, drives bolt 124 and is used for bobbin 116 is fixed to the wing nut 125 of trimmer head housing 114.

Preferably, trimmer housing and bobbin are formed by the counterpart member identical materials with previous embodiment.Housing 114 limits upper circular walls 126, from described circular wall sagging tubular skirt section 128 and the tubulose extension 130 that is provided with placed in the middle.Described tubulose extension 130 is aimed at the pivot axis " Y " of head, and comprises dip portion 130a and protrude upward the 130b of portion.Described tubulose extension 130 is configured to receive driving bolt 124, and the cross section that protrudes upward the 130b of portion is preferably square square head portion 124a with fitted bolt, and the radius of dip portion 130a is that the constant that reduces is to receive the 124b of cylindrical body portion that drives bolt.Lower shaft portion 124c extends downwards and the inside by housing, then extends to bobbin, is threadably engaged by wing nut 125 at this place, as will be described below such (for example seeing Figure 29).

Drive bolt 124 and also limit tapped cylindrical (not shown), described cylindrical extends axially the entity part by the middle part of head and trimmer, to engage with the drive shaft screw thread of trimmer, as formerly the collision of embodiment is supplied with in the head.Therefore, by will driving in the tubulose extension 130 that bolt 124 is arranged on trimmer head housing 114 and it is combined with drive shaft screw thread, thereby the rotation of driving shaft drives bolt owing to the interference engagement between the top 130b of square head portion 124a that drives bolt and extension 130 makes and housing correspondingly rotates (being generally counterclockwise).And the cross section on the top of tubulose extension can also form other different shape to form the interference engagement of needs in the head that drives bolt and the housing except square.

Trimmer head housing 114 also limits a pair of relative groove 180 in sagging tubular skirt section 128.Groove 180 is at its bottom end opening, and described groove 180 is suitable for receiving a pair of relative outlet eye thimble 178 slidably with Press fitting.Alternatively, identical with previous embodiment, described eye thimble can be press-fitted by the hole in the shell skirt.And preferably, the part of the described eye thimble of adjacency of shell skirt 128 is raised or is outward-dipping, invades and harasses in use to protect eye thimble to avoid foreign matter.Be formed with a plurality of radially-protruding cooling fins 115 on the upper wall 126 of housing 114, described cooling fin extends upward along the top 130b of tubulose extension 130.Preferably, described cooling fin 115 surface 117 that is provided with sharpening is used to cut off near the axial weeds of driving that in use may be wound up into the trimmer head.A plurality of equally spaced driving lug receiver holes 119 extend axially the upper wall 126 by the trimmer housing, and described hole 119 is adapted to be received in and limits the upwardly extending projection that drives lug 121 on the bobbin, as will be descr.

The lower annular flange 172 that described trimmer head bobbin 116 limits upper, annular flange 170 and carried by cylindrical body part 174, between

flange

170 and 172, to limit annular region 176, described annular region is used to load the coil around the flexible nylon line of cut 17 of body part 174 windings, after assembling, the end 17 of line of cut ' will stretch out to pass exports eye thimble 178 like this.Bobbin also comprises from the sagging lower body part 175 of lower flange 172.Bobbin 116 also comprises sagging tubular extension 131, described extension 131 is being aimed at the tubulose extension 130 on the trimmer head housing 114 after the assembling, as shown in figure 39, thereby the lower shaft portion 124c with screw thread that drives on the bolt 124 extends through extension 131, and extend to by in the external zone of the lower body portion 175 of bobbin, be threadably engaged by wing nut 125 at this zone middle shaft part.

Extend around the sagging extension 131 of helical spring 122 in bobbin, below upper bobbin flange 170 and the annular concave surface 125 in the top of wing nut 125 ', and between them, extend.After fixing like this, bobbin 116 and trimmer head housing 114 are pressed against together by helical spring 122.In this fixed position, driving lug 121 protrudes upward from the upper surface of flange 170, enter in the driving lug receiver hole 119 in the trimmer head housing, bobbin is fixed to the trimmer housing, thereby housing is passed to bobbin in the rotation that drives under the bolt effect.For bobbin is pulled down from the trimmer head housing, only need make wing nut 125 break away from the lower shaft portion that drives bolt and get final product by screw thread with screw thread.

In order to need not to twine around bobbin 116 from the line that housing is pulled down bobbin and can be made trimmer, upper bobbin flange 170 is provided with a pair of inner end 17 that is used for the line of cut 17 of two independent length of clamping " relative line receiver 191.The size of bobbin 116 and structure are defined as making flange 170 and line to export eyelet 178 planar alignment.Each line receiver 191 that comprises line receiver passage 193 has identical structure with line receiver 91 among the previous embodiment, and plays a role in an identical manner.Its size can according to the change in size of each bobbin and at its design head line of cut vary in diameter and change slightly.

Except including on the bobbin 116 line receiver 191, a plurality of actuate slopes 123 of the inner surface 126 of the upper wall 126 of trimmer head housing 114 ' also be provided with.Each lug receiver hole 119 of such slope abuts also extends to next hole from each lug receiver hole 119, as shown in figure 26.In the embodiment of as shown in the figure trimmer head 100, inclined-plane 123 is configured to them respectively along arc path, and from side direction in abutting connection with and position below the inner surface 126 of upper housing wall 126 ' slightly begin to dip down and tiltedly extend, thereby the rear side of lug receiver hole limit vertical step 119 '.Then inclined-plane 123 the inner surface 126 that transits to upper housing wall near next lug receiver hole 119 places glossily backward '.Like this, when the lower body portion 174 of clamping bobbin 116 ' and keeping the trimmer head housing static different in the counterclockwise direction during rotating bobbin, drive lug each hole 119 from the upper wall of trimmer head housing around step 119 ' to the inclined-plane, lower edge move to the inner surface 126 of upper housing wall ', then under the effect of spring 122, be moved upward in the next position lug receiver hole.Therefore, bobbin will make bobbin carry out clutch or reciprocating motion in housing relative to continuous rotation of housing, this clutch or reciprocating motion and above identical to described in the discussion of first embodiment of the invention.

Step 119 ' anti-the principal vertical line that is limited by the vertical spacing between the upper end on the outer surface of housing upper wall 126 and inclined-plane 123 any shake or backlash in use causes that bobbin reverse rotation and line accident emit.For this purpose, adopt highly about 0.015 inch-0.025 inch vertical step.For make drive lug 121 under the effect of manual rotating bobbin 116, cross reposefully step 119 ', the upper surface (in activation point, described upper surface is roughly concordant with the upper surface of housing wall 126) that makes lug 121 ' locate circular.Adopted radius be about 0.030 inch surface 121 '.Although drive lug 121 rotations leave the inclined-plane and rotate to inner housing wall surface 126 ' on the time, inclined-plane 123 makes upper bobbin flange 170 and the line receiver 191 in it is vertically aimed at eyelet 178, but preferably, trimmer housing 114 is determined the size of bobbin 116 relatively, thereby when driving lug 121 was arranged in the lug receiver hole, relative line receiver was radially aimed at eyelet.Under any situation, can easily realize the radially aligning between receiver and the eyelet.

Like this, the same with previous embodiment, rotate described bobbin by as mentioned above the elongated end of line being pressed in the line receiver and with respect to described housing, thereby twine the line of cut 17 of described length around described bobbin.In bobbin when rotation, is when line comes out and when pasting the flat side direction guide wall pulling of adjacent channel outlet, the line of described length bends towards bobbin inside sharp from receiver channel.Along with bobbin continues rotation, owing to described driving lug repeatedly moves and upwards is snapped in next receiver hole along inclined downward, thereby bobbin vertically moves back and forth with respect to housing.As a result, cause line to be wrapped in equably on the bobbin, avoided the line entanglement simultaneously, as previous embodiment.

At last, the same with previous embodiment, the various remodeling of line receiver structure, quantity and size can be used in the manual head 100, so that required clamping to be provided to line, and the line of reception various sizes, also be suitable for certainly from the quantity of the line of cut of cutting head extension.In addition, the orientation on driving lug 121, hole 199 and inclined-plane 123 can be changed or exchange.For example, described driving lug can be formed on the described upper housing wall, and described hole and can be formed in abutting connection with the inclined-plane in the upper surface of described bobbin.

The third embodiment of the present invention has been shown in Figure 32 to Figure 44.Trimmer head 200 shown in the figure is collision supply-type head, and described head has in U.S. Patent No. 4,959, disclosed driving mechanism and line feed mechanism in 904, but this head is modified as and comprises that Express Order Wire of the present invention loads feature portion.As will be shown, the main distinction that head 10 is supplied with in the collision of the trimmer head 200 and first embodiment is in trimmer head 200, cam, directly is molded in the bobbin and trimmer head housing in the trimmer head 200 by the cam member 18 of the axial installation in the head 10 and cam butt that cam follower 20 limits and sliding surface.

Trimmer head 200 comprises: housing 214, bobbin 216, helical spring 222 and driving bolt 224.Described housing comprises top 214a and bottom 214b, and they releasably are fixed together around described bobbin.In addition, described trimmer head housing and bobbin are preferably formed by the material identical materials with the respective members of previous embodiment.Circular wall 226 in the described upper shell 214a qualification, go up the sagging tubular skirt section 228 of circular wall and at the tubulose extension 230 that is provided with placed in the middle from described.Extension 230 is aimed at vertically with the centre rotational axis line of head, and comprises hanging portion 230a and the part 230b that protrudes upward.In addition, described tubulose extension 230 is constructed to receive and drives bolt 224, and the cross section of the top 224a of described driving bolt is circular, and the cross section of its underpart 224b is that hexagon is to match with hexagonal bottom 230a of tubulose extension.The bottom of described driving bolt and the tubulose extension in the housing also can be square or other structure comes to provide required interference engagement between driving bolt and housing.Described driving bolt 224 is secured in the tubulose extension 230 by extension 230 is carried out thermal contraction round bolt.Be provided with cannelure 224e round described driving bolt,, between bolt and housing, produce interference engagement, thereby promote bolt to housing with when the plastic casing material shrinks.Also can adopt other device will drive bolt to housing.Drive bolt 224 and also limit internal thread cylindricality hole 224f, described internal thread cylindricality hole extends axially passes the driving bolt, to engage with the drive shaft screw thread of trimmer as among the previous embodiment.The second tubulose extension 211 that is radially spaced from the dip portion 230a of extension 230 extends downwards from the inner surface of upper housing wall 226, be defined in its lower end helical spring 222 on annular seating 213.

The top of described housing 214 also is limited to a pair of relative groove 277 in the sagging barrel-type casing skirt section 228.Identical with previous embodiment, the lower end of groove 280 is opened wide and is suitable for receiving a pair of relative metal outlet eye thimble 278 by compression-style fittings.Alternatively, as among first embodiment, described eye thimble can be press-fitted by the hole in the shell skirt.In addition, the part in abutting connection with eye thimble of shell skirt preferably raises or is outward-dipping, not invaded and harassed by foreign matter with the protection eye thimble, and a plurality of radially-protruding cooling fin 215 is formed on the upper wall 226 of upper shell.A plurality of equal angles settings and outwardly directed radially protuberance 233 also are arranged on the lower end in skirt section 228, as will be descr lower house part 214b is fixed to top 214a.

The upper wall 226 of trimmer head housing has the middle part 227 of rise, and limits indent zone 229 in described middle part.As shown in figure 38, limit the projection 244 that four equal angles are provided with around described recessed regional 229 peripheral wall surfaces of extending 231, described protruding 244 inwardly extend radially out from wall 231.Each projection limits the surface 244 ' that a diagonal form is provided with, and this intersects 135 ° and parallel with the rotation of head to surface 244 '.These projectioies structurally are similar to the projection 56 on the cam follower 20 of first embodiment, but bigger than them.Yet here, these projectioies will limit cam face, rather than the cam bearing surface.

Front surface on each projection 244 limits overhead cam 244a (counter clockwise direction of observing from the top).Each rear surface limits goes up slidingsurface 244b.The surface of each cam is also parallel with the rotation of head.Especially on the small size head, described upward slidingsurface 244b can be downward-sloping, preferably is cut into fillet, with the loaded line of being convenient to as described below.

The lower casing body 214b of described trimmer head 200 limits: be positioned at the circular open 235, the annular horizontal surface 237 that is provided with around opening 235 of expansion of downside of lower casing body and the groove 239 (showing four) that is provided with in abutting connection with a plurality of equal angles of the upper surface 241 of lower casing body 214b, described groove is used to receive the locking protuberance 233 of the respective numbers on the upper casing body 214a.Groove 239 is provided with narrower offset portion 239 ', as shown in figure 35, and at least one locking protuberance 233a is installed on the cantilever portion 228 ' of shell skirt, thereby has elasticity, like this, in three grooves that rigid locking protuberance 233 are inserted in the lower casing body, radially inwardly push elastic protrusion part 233a, to be pressed in the remaining alignment slot, and when being rotated counterclockwise the top of housing with respect to lower part of frame, described locking protuberance will move in the offset portion of described groove, thereby described two housing parts releasably are fixed together.

As shown in figure 40, lower casing body 214b further on annular surface 237, limit adjacent openings 235 the projection 246 that is provided with of four equal angles.Be similar to the surface 244 ' in the projection 244 in the upper casing body, the surface 246 ' that the dihedral on the projection 246 is provided with limits following cam 246a and the lower slider surface 246b that dihedral is provided with.Following cam 246a is positioned on the front surface of projection, and is parallel to the rotation extension of cutting head, also with the described angle that becomes 135 ° in abutting connection with slidingsurface.Described slidingsurface 246b also can the mode identical with the slidingsurface 46b on the following cam 46 among first embodiment upwards be cut into fillet.Yet, in a preferred embodiment, slidingsurface 246b on the lower convexity 246 is not 135 ° with respect to the angle of cam face 246a, but is less angle as shown in Figure 40, constructs with the preferred angled of holding as will be descr on the following cam follower front side that is limited by bobbin.

Upper flange 270 and lower flange 272 that bobbin 216 in the trimmer head 200 limits by 274 carryings of tubular upper body part, thereby limit the annular region 276 between upper flange 270 and the lower flange 272, described annular region is used to load the coil around the flexible nylon line of cut 17 of body part 274 windings, like this, when assembling, the end 17 ' of line of cut will stretch out and pass outlet eye thimble 278.The cylindrical chamber 243 that the upper end is opened wide is provided with around the centre rotational axis line.Annular upstanding wall 245 is arranged in the lower end of chamber 243, to limit the spring receiving area 247 and the lower spring cup 247 ' of annular.The lower body portion 275 of bobbin ends at impinger 281, and radial flange 249 stretches out from the lower lower body part, retains between bobbin 216 and the lower casing body 214b (seeing Figure 36) to prevent chip.During head 200, helical spring 222 extends round extension 230 in assembling, against and between the seat of honour 213 that upper casing body 214a forms and the lower spring cup 247 ' in the bobbin 216, extend, as shown in Figure 36 and Figure 37.Impinger 281 on the described reel bottom stretches out by the opening 235 in the lower casing body 214b bottom, like this impinger 281 can with collision on the ground to emit extra line of cut, shown in first embodiment by relative eye thimble 278.

The upper flange 270 of bobbin 216 surface thereon go up to limit overhead cam driven member 256, and lower spool flange 272 fixs cam follower 257 in its lower surface upper limit, as shown in Figure 42 to Figure 44.Although can adopt other structure, cam follower all is preferably square structure, and distributing limits four vertical surfaces 256 ' and 257 ', and staggers 45 ° with respect to the centre rotational axis line of trimmer head.The cam abutment surface 256a that front surface by overhead cam and following cam limits is also parallel with the rotation of head with 257a.The front surface of the qualification slidingsurface 257b of following cam follower can be inclined upwardly near the bight on it, so that clutch more smoothly to be provided where necessary.And the front surface of overhead cam driven member also can be downward-sloping so that supply line.Back edge 256b downward-sloping it is believed that the short less head of length on each cam follower surface wherein is very important, otherwise the relative rotation that may make bobbin and housing in the line winding process is difficulty more.Can prove that also it is favourable that the rear surface that makes overhead cam and following cam tilts.

In preferred structure, slidingsurface 257b on the following cam follower is limited by the inclined-plane that tilts, as Figure 34, Figure 42 and shown in Figure 44, owing to relax more, therefore in being wound into process on the bobbin, line of cut can make bobbin clutch more smoothly than the inclination that the surface provided of being cut into fillet.Such as noted above, when when trimmer head and collision on the ground move up bobbin 216 when emitting ew line, thereby and in manual rotating bobbin is wound into line of cut process on the bobbin, the corresponding slidingsurface 246b that by lower casing body limited of projection on 246 slopes inwardly than the respective surfaces on the projection 244 on the upper casing body 214a steeplyer, holds these inclined ramp on protruding 224 with more spaces that the slidingsurface on the adjacent lobes 246 is provided.

The collision feed mechanism that provides by overhead cam and following cam and cam follower operate in referenced patent No.4, detailed explanation is arranged in 959,904.Yet should be noted in the discussion above that the cam follower that is carried by upper bobbin flange and lower spool flange in the head 200 is called overhead cam and following cam in referenced patent, but overhead cam in the head 200 and following cam are called as cam follower in referenced patent.As the more detailed explanation in the reference paper of quoting, in use, the following cam bearing surface under following cam 246a aligning on the lower casing body 214b and the butt on the rear surface of cam follower 257.Therefore, when housing rotated in the counterclockwise direction by trimmer drive, bobbin rotated with housing.At this activation point, overhead cam 244a is upwards spaced apart with overhead cam driven member 256, and cam produces driving force so only pass through down.When impinger 281 is pressed to ground, bobbin 216 is forced upwardly in housing, to remove down engaging of following cam bearing surface 257a and following cam 246 on the cam follower, and make the overhead cam bearing surface 256a on the overhead cam driven member 256 aim at also butt overhead cam 244a immediately, thereby only produce driving force by overhead cam.When impinger 281 is lifted on ground, helical spring 222 forces bobbin downward, removing the joint of overhead cam driven member and overhead cam, and cam follower is engaged again with following cam.Therefore, as the first embodiment of the present invention, each collision on ground is produced the effect of bobbin and the relative half-twist of housing, and have nothing to do with the duration of colliding.In this counterrotating process, centrifugal force causes the new line of cut of scheduled volume to be emitted by the relative eye thimble 278 in the trimmer head housing.

For the quick loading around bobbin 216 of line that trimmer is provided, upper bobbin flange 270 is provided with a pair of relative line receiver 291, with the inner end 17 of the line of cut 17 of two independent length of clamping ".The size of bobbin 216 and structure are defined as making the upper flange 270 and eye outlet opening 278 planar alignment on the bobbin.Comprise that each line receiver 291 of line receiver passage 293 and the line receiver among the previous embodiment have identical construction, and play a role in an identical manner.In addition, size can according to the change in size of each bobbin and at its design head line of cut vary in diameter and change slightly.Above-mentioned cam, cam bearing surface and sliding surface to be matching with the essentially identical mode of cam, butt and sliding surface that collision is supplied with among first embodiment of head, so that bobbin moves back and forth in housing, thereby line is evenly distributed on the bobbin.When bobbin 216 by impinger 281 clampings, and when rotating in the counterclockwise direction with respect to housing, lower slider surface 257b on the following cam follower 257 causes bobbin to move up with respect to housing the rear surface 246b on the butt lower convexity 246, thus compression helical spring 222.When continuing manual rotating bobbin, the projection 246 in the lower part of frame will be crossed and avoid in the bight of following cam follower 257, and spring will thereby cause bobbin to engage downwards, like this lower convexity and following cam bearing surface planar alignment once more.Because the last slidingsurface on last protruding 244 and preceding (slip) surface on the overhead cam driven member 256 connect, thereby line of cut is wound on the bobbin during engaging bobbin 216 downwards at helical spring 222 at every turn, can proves that therefore the front surface 244b that makes projection 244 and/or preceding (slips) surperficial 256b inclination of overhead cam driven member 256 are favourable to bobbin is provided with respect to rotating more smoothly of housing in the process of loaded line.

As at referenced patent No.4, point out in 959,904 like that, the collision feed mechanism that provides by cam and cam bearing surface is not necessarily limited to square cam follower (or as point out cam) in referenced patent.Concerning trimmer head 200 also is the same.For example, overhead cam driven member and following cam follower that upper bobbin and lower lower form can have three faces or five faces, and as referenced patent No.4, Figure 12 of 959,904 is to shown in Figure 15.The cam follower of three faces or five faces can cooperate with the cam abutting member of equivalent in upper shell and the lower house, as shown in reference to the accompanying drawings.In addition, basic identical in the function of this cam and cam follower, cooperation and running and above-mentioned and the referenced patent.

Under the situation that does not break away from the spirit and scope of the present invention, can carry out various variations and remodeling to the present invention.For example the bobbin that is adopted among the present invention can be formed with single flange, and line will twine around the spool body between the part of this flange and housing.Single line receiver or a plurality of line receiver still can be arranged in the single flange.As long as these and other variation and remodeling are within the scope of the appended claims, they will be considered to a part of the present invention.

Claims

1. trimmer head, the flexible line of cut of its at least one length in flexible line rotary trimmers uses, and described trimmer head comprises:

Housing, it is suitable for operatively being connected to rotary trimmers so that described trimmer head rotates, and described housing limits the sagging skirt section of tubular, has at least one outlet opening in the sagging skirt section of described tubular:

Bobbin, it operatively is connected to described housing, in drive pattern, to rotate around common axis with described housing, and rotate with respect to described housing in the online winding pattern, described bobbin comprises cylindrical body part and from radially-protruding at least one flange of described body part, thereby around described body part and in abutting connection with described flange limit line of cut storage area, being operatively connected between described bobbin and the described flange makes and produce moving mutually along described common rotating shaft line when described bobbin rotates with respect to described housing between described bobbin and described housing; And

At least one line receiver, it is formed in the described flange, described receiver comprises the passage that extends internally, described passage limits when described bobbin is relative with described housing can aim at the outer end of the outlet opening in the described skirt section when rotating, and wherein, the outside at least of described passage formed by a plurality of walls, thereby cross section is a polygon, described wall limits such surface, promptly be inserted in the described passage by described outlet opening in the end of described line, the part of the described line that extends from described passage is by the described body part guiding towards described bobbin, and described bobbin is during with respect to described housing rotation, the line of cut of described surperficial clamping certain-length.

2. trimmer head according to claim 1, the cross section of the described at least outside of the described passage in the wherein said receiver is a hexagon.

3. trimmer head according to claim 1, the inner at least inwardly convergent of the described passage in the wherein said receiver.

4. trimmer head according to claim 2, the inner at least inwardly convergent of the described passage in the wherein said receiver.

5. trimmer head according to claim 1, it comprises in abutting connection with the line spigot surface of the described outer end of described passage, inwardly guides from the described part of the described line of described passage extension with the described body part towards described bobbin.

6. trimmer head according to claim 1, wherein said passage limits the linear center axis and described passage radially extends through described line receiver, makes the described central axis of described passage and described common axis intersect.

7. trimmer head according to claim 1, wherein said passage limits the linear center axis, and described axis is at the place, described outer end of described passage and the tangent line formation acute angle of described flange.

8. trimmer head according to claim 1, the outside at least cross section of the described passage in the wherein said receiver is a rhombus.

9. trimmer head according to claim 1, the cross section of the described at least outside of the described passage in the wherein said receiver is a triangle.

10. trimmer head according to claim 5, wherein said passage limits the linear center axis, and wherein, at least a portion of the described outer end of the described passage in the described line receiver of the adjacency of described line spigot surface is linear, and limit the central longitudinal axis along its extension, described central longitudinal axis intersects with the described central axis of described passage.

11. trimmer head according to claim 5, the first of the described outer end of the described passage in the described line receiver of the adjacency of wherein said line spigot surface extends laterally from the described outer end of described passage, and the second portion of described line spigot surface is from described first side direction and extend internally.

12. trimmer head according to claim 5, at least a portion of the described outer end of the described passage in the described line receiver of the adjacency of wherein said line spigot surface is linear, and limit central longitudinal axis along its extension, and wherein, at least the described outside of described passage is formed by a plurality of pinch wall, limiting corresponding a plurality of passages bight, described passage is oriented to and makes the described longitudinal axis of described part of described spigot surface intersect with the described linear center axis of described passage and at least one bight in the described passage bight.

13. trimmer head according to claim 12, the cross section of the described at least outside of the described passage in the wherein said receiver is a hexagon.

14. trimmer head according to claim 12, the cross section of the described at least outside of the described passage in the wherein said receiver is a rhombus.

15. trimmer head according to claim 12, the cross section of the described at least outside of the described passage in the wherein said receiver is a triangle.

16. trimmer head according to claim 12, the inner at least inwardly convergent of the described passage in the wherein said receiver.

17. trimmer head according to claim 12, the described central axis of wherein said passage also are defined as acute angle with respect to the described longitudinal axis of the described part of described spigot surface.

18. a trimmer head, the flexible line of cut of its at least one length in flexible line rotary trimmers uses, and described trimmer head comprises:

Housing, it is suitable for operatively being connected to rotary trimmers so that described trimmer head rotates, and described housing limits the sagging skirt section of tubular, has at least one outlet opening in the sagging skirt section of described tubular;

Bobbin, it operatively is connected to described housing, in drive pattern, to rotate around common axis with described housing, and rotate with respect to described housing in the online winding pattern, described bobbin comprises cylindrical body part and from radially-protruding at least one flange of described body part, thereby around described body part in abutting connection with described flange limit line of cut storage area, being operatively connected between described bobbin and the described flange makes and produce moving mutually along described common rotating shaft line when described bobbin rotates with respect to described housing between described bobbin and described housing; And

At least one line receiver, it is formed in the described flange, described receiver comprises the passage that extends internally, described passage limits the outer end that can aim at the outlet opening in the described skirt section when the relative rotation of described bobbin and described housing, and wherein, at least the outside cross section of structure like this that limits of described passage, promptly, when the described end of described line is inserted in the described passage by described outlet opening, the part of the line that extends from described passage is by towards the described body part side direction of described bobbin and inwardly guiding, and when described bobbin rotates with respect to described housing, the line of cut of clamping certain-length.

19. trimmer head according to claim 18, the inner at least inwardly convergent of wherein said passage.

20. trimmer head according to claim 18, the cross section of the described at least outside of wherein said passage is a hexagon, and wherein, each described line receiver comprises also that in abutting connection with the line spigot surface of the described outer end of described passage described line spigot surface is used for inwardly guiding from the part of the line of described passage extension towards the described body part of described bobbin.

21. trimmer head according to claim 20, wherein said spigot surface comprises in abutting connection with the described outer end of described passage and the first that extends laterally from described outer end, and in abutting connection with described first and from described first side direction and the second portion that extends internally.

22. trimmer head according to claim 18, wherein said reciprocator comprises being operatively connected between described bobbin and the described housing, and be included in the isolated projection of a plurality of equal angles on described bobbin or the described housing, with be formed on described housing or the described bobbin to receive corresponding a plurality of holes of described projection, each described hole limits front wall section and rear wall section, described front wall section has the axial length longer than described rear wall section, one spring member pushes described projection in the described hole, thereby described trimmer head makes the described front wall section of described projection against described hole along the rotation of described first direction, and make described bobbin along the corresponding rotation of described first direction, and the curve slope of corresponding a plurality of inclinations, each described inclined-plane extends to the rear surface in another described hole from the position near a described hole the arc inclined path, like this, when described bobbin along described first direction during with respect to the rotation of described housing, described projection is crossed the described rear wall section in described hole repeatedly, inclined ramp along adjacency, and under the effect of the power of described spring member, enter in another hole, thereby make described bobbin move back and forth along described common axis with respect to described housing.

23. trimmer head according to claim 18, thereby wherein said trimmer head is to be suitable for colliding the type that the predetermined length line is realized supplying with in ground, and described trimmer head further comprises perpendicular alignmnet, overhead cam that shape is similar and rotation is staggered and following cam, described be connected to cam-operatedly described housing with therewith the rotation, each described cam limits a plurality of cam faces thereon, and cam follower member, described cam pack operatively is connected to described bobbin to rotate therewith and to limit a plurality of cam abutment surface, described cam abutment surface be suitable in response to described trimmer head to the bump on ground and with predetermined increment of rotation selectively with described cam, thereby in described first direction rotation, described bobbin is vertically moved in described housing at described trimmer head and described bobbin, between described bobbin and described housing, produce rotation relatively thus, thereby outwards supply the line of predetermined length by the described outlet opening in the described housing, and wherein, at least one cam and described cam follower member in the described cam limit a slidingsurface, this slidingsurface and each described cam face and described cam abutment surface in abutting connection with and on angle, stagger, thereby when being wrapped in described line on the described bobbin, allow described bobbin to rotate along described first direction, and make described bobbin move back and forth with respect to described housing with respect to described housing.

24. trimmer head according to claim 18, wherein said cross section are oval, thereby limit long axis of pitch, hyphen to axis with perpendicular to the linear center axis of described long axis and described minor axis, are used for the line of cut of the described length of clamping.

25. be provided with the surface imperfection thing in the described passage in the trimmer head according to claim 18, wherein said receiver, be used for the line of cut of the described length of clamping.