CN111149505B

CN111149505B - Grass trimmer

Info

Publication number: CN111149505B
Application number: CN201811324530.6A
Authority: CN
Inventors: 张棋; 冯继丰
Original assignee: Nanjing Chervon Industry Co Ltd
Current assignee: Nanjing Chervon Industry Co Ltd
Priority date: 2018-11-08
Filing date: 2018-11-08
Publication date: 2022-07-15
Anticipated expiration: 2038-11-08
Also published as: CN111149505A

Abstract

The invention relates to the technical field of garden tools, and particularly discloses a grass trimmer, which comprises a handle and a grass trimming head, wherein the grass trimming head comprises a shell and a rotor rotationally connected with the shell, and further comprises a limiting mechanism used for limiting the rotor to rotate in one direction relative to the shell; the limiting mechanism comprises a plurality of limiting convex ribs, a pawl and a torsion spring, the limiting convex ribs are uniformly distributed along the circumferential direction of the rotating body, and the pawl is rotationally arranged on the shell; the two ends of the torsion spring are respectively connected with the pawl and the shell, and the torsion spring is configured to enable the tail end of the pawl to abut against one of the limiting convex ribs. In the grass cutting state, the limiting convex ribs are abutted with the pawls, so that the rotating body and the shell rotate synchronously; when strikeing unwrapping wire and wire winding, relative motion takes place between rotor and the casing, under the condition of not dismantling the head of beating grass, can accomplish smoothly and strike unwrapping wire and wire winding, and need not overcome axial load, convenient operation improves work efficiency.

Description

Grass trimmer

Technical Field

The invention relates to the technical field of garden tools, in particular to a grass trimmer.

Background

A grass trimmer is a garden tool and is used for trimming lawns. The grass trimmer comprises a grass trimming head, the grass trimming head comprises a spool for winding a grass trimming line, and the grass trimming head rotates at a high speed to drive the grass trimming line mounted on the grass trimming head to rotate so as to realize the cutting function of the lawn.

When grass cutting is performed, the grass cutting line is gradually consumed due to wear. After the grass mowing line is used up after a period of operation is carried out, a user needs to replace the grass mowing line with a new grass mowing line and wind the grass mowing line on the spool. Traditional grass cutting head when changing the line of beating grass, needs to dismantle the casing of beating the grass head and changes, has reduced work efficiency. Traditional outer wiring grass cutting head, though need not dismantle grass cutting head, but be provided with the driving surface of a circumferencial direction between spool and casing, at the wire winding in-process or strike the unwrapping wire in-process, need an axial motion to stagger this driving surface, the axial motion load is big for the wire winding load is big, and the operation is inconvenient.

Disclosure of Invention

The invention aims to provide a grass trimmer to solve the technical problem that winding and knocking paying-off are inconvenient in the prior art.

As the conception, the technical scheme adopted by the invention is as follows:

a grass trimmer comprises a handle and a grass trimming head, wherein the grass trimming head comprises a machine shell and a rotor which is rotationally connected with the machine shell, and further comprises a limiting mechanism which is used for limiting the rotor to enable the rotor to rotate in a single direction relative to the machine shell;

The stop gear includes:

the limiting convex ribs are uniformly distributed along the circumferential direction of the rotating body;

the pawl is rotationally arranged on the shell;

the two ends of the torsion spring are respectively connected with the pawl and the shell, and under the action of the torsion spring, the torsion spring is configured to enable the tail end of the pawl to abut against one of the limiting convex ribs.

The rotating body comprises a wire spool positioned in the casing and a knob rotatably connected with the casing, and the knob is connected with the wire spool and coaxially arranged; the casing includes interconnect's upper cover and lower cover, the knob set up in the lower extreme of lower cover.

The pawl is arranged on the lower surface of the lower cover, and the limiting convex rib is arranged on the knob.

The rotor still includes the adapter sleeve, the adapter sleeve is located in the casing and connect the knob with the wire reel.

The connecting sleeve is connected with the knob through a screw, and the connecting sleeve is connected with the wire spool in a clamping mode.

Wherein, the pawl set up in on the lower surface of upper cover, the rotor still includes the transmission seat, the transmission seat connect in the upper end of wire reel just spacing protruding muscle set up in on the transmission seat.

Wherein, it is provided with the cylinder arch to rotate on the casing, the pawl rotates the cover and locates on the cylinder arch, the one end embedding of torsional spring the pawl, the other end embedding of torsional spring on the casing, the part of torsional spring twine in on the cylinder arch.

Wherein, the balance blocks are arranged on the shell at the positions symmetrical to the pawls.

And in the process that the rotor drives the limiting convex ribs to rotate, the pawl is contacted with one limiting convex rib at most.

When the tail end of the pawl abuts against one of the limiting convex ribs, the sum of the torque of the rotating body and the torque of the torsion spring is larger than the torque of the pawl.

The invention has the beneficial effects that:

when the rotating body rotates clockwise, the limiting convex rib on the rotating body pushes the pawl to further drive the shell to rotate, and the limiting convex rib and the pawl are always in an abutting state; when the rotor is knocked to pay off, the rotor is in contact with the ground and stalls instantly, the casing continues to rotate clockwise under the action of inertia, the tail end of the pawl is separated from the current abutted limiting convex rib, the pawl rotates anticlockwise under the action of centrifugal force, the pawl is completely separated from the current abutted limiting convex rib, when the rotor leaves the ground, the rotating speed is recovered, the head end of the pawl is impacted by the limiting convex rib, so that the tail end of the pawl is abutted to the other limiting convex rib, relative motion is generated between the rotor and the casing, and one-time pay-off is completed; when winding, the rotating body is driven to rotate anticlockwise, so that the tail end of the pawl is separated from the limit convex rib which is abutted currently, and the tail end of the pawl is abutted against the other limit convex rib under the action of the torsion spring to drive the rotating body to rotate continuously anticlockwise so as to finish winding; to sum up, under the condition of not dismantling the head of beating the grass, can accomplish smoothly and strike unwrapping wire and wire winding, and need not overcome axial load, convenient operation improves work efficiency.

Drawings

FIG. 1 is a schematic view of a grass trimmer according to an embodiment of the present invention;

FIG. 2 is a top view of a grass cutting head of the grass trimmer according to one embodiment of the present invention;

FIG. 3 is a sectional view taken along line A-A of FIG. 2;

FIG. 4 is a front view of a grass cutting head of the grass trimmer according to one embodiment of the present invention;

FIG. 5 is a sectional view taken along line B-B of FIG. 4;

FIG. 6 is a first exploded view of a grass cutting head of the grass trimmer according to a first embodiment of the present invention;

FIG. 7 is a schematic view of a second exploded structure of a grass cutting head of the grass trimmer according to the first embodiment of the present invention;

FIG. 8 is a third exploded view of the grass cutting head of the grass trimmer according to the first embodiment of the present invention;

FIGS. 9 to 15 are schematic views showing the working state of the grass cutting head of the grass trimmer according to the first embodiment of the present invention;

FIG. 16 is a schematic view showing a first exploded view of a grass cutting head of a grass trimmer according to a second embodiment of the present invention;

FIG. 17 is a second exploded view of the grass trimmer head according to the second embodiment of the present invention;

FIG. 18 is a schematic view of a part of the structure of the grass-mowing head of the grass mower according to the second embodiment of the present invention.

In the figure:

11. a handle;

12. a housing; 121. an upper cover; 122. a lower cover; 123. a cylindrical bulge; 124. a counterbalance;

13. A rotating body; 131. a wire spool; 132. a knob; 133. connecting sleeves; 134. a spring;

14. grass line cutting;

151. limiting convex ribs; 152. a pawl; 153. a torsion spring; 1511. a first limit convex rib; 1512. a second limit convex rib; 1513. a third limiting convex rib; 1514. a fourth limiting convex rib; 1515. a fifth limiting convex rib; 1516. a sixth limiting convex rib;

16. a motor;

221. an upper cover; 222. a lower cover; 223. a cylindrical bulge; 224. a counterbalance;

231. a wire spool; 232. a knob; 233. a transmission seat;

251. limiting convex ribs; 252. a pawl.

Detailed Description

In order to make the technical problems solved, the technical solutions adopted and the technical effects achieved by the present invention clearer, the technical solutions of the present invention are further described below by way of specific embodiments with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the elements associated with the present invention are shown in the drawings.

Example one

Referring to fig. 1 to 8, the embodiment of the invention provides a grass trimmer, which comprises a handle 11 and a grass trimming head. The grass cutting head comprises a machine shell 12 and a rotating body 13 rotatably connected with the machine shell 12, the rotating body 13 comprises a wire spool 131 positioned in the machine shell 12 and a knob 132 rotatably connected with the machine shell 12, the knob 132 is connected with the wire spool 131 and coaxially arranged, and the wire spool 131 can be driven to rotate by rotating the knob 132, or when the wire spool 131 rotates, the knob 132 can be driven to rotate. The wire spool 131 is wound with the grass mowing line 14, and when the wire spool 131 rotates, the grass mowing line 14 is driven to rotate to finish grass mowing.

For convenience of installation, the knob 132 is connected to the wire spool 131 by a connecting sleeve 133, the connecting sleeve 133 is located in the housing 12, the connecting sleeve 133 is connected to the knob 132 by a screw, and the connecting sleeve 133 is engaged with the wire spool 131. A spring 134 is arranged between the connecting sleeve 133 and the wire spool 131 to ensure that the connecting sleeve 133 and the wire spool 131 are tightly abutted and connected.

In order to restrict the rotation of the rotor 13 in one direction with respect to the housing 12, a stopper mechanism is provided in the mowing head. The limiting mechanism comprises a plurality of limiting convex ribs 151, a pawl 152 and a torsion spring 153, the limiting convex ribs 151 are evenly distributed along the circumferential direction of the rotating body 13, the pawl 152 is rotatably arranged on the machine shell 12, the two ends of the torsion spring 153 are respectively connected with the pawl 152 and the machine shell 12, and the torsion spring 153 is configured to enable the tail end of the pawl 152 to abut against one of the limiting convex ribs 151, namely, under the action of the torsion spring 153, the pawl 152 tends to abut against one side of one of the limiting convex ribs 151.

The case 12 is provided with a cylindrical protrusion 123, the pawl 152 is rotatably sleeved on the cylindrical protrusion 123, one end of the torsion spring 153 is embedded in the pawl 152, the other end of the torsion spring 153 is embedded in the case 12, and a part of the torsion spring 153 is wound on the cylindrical protrusion 123. When the pawl 152 rotates, the force of the torsion spring 153 acts on the pawl 152 so that the pawl 152 always has a tendency to abut against the side of the limit projection 151. In the process that the rotating body 13 drives the limiting convex ribs 151 to rotate, the pawl 152 is contacted with one limiting convex rib 151 at most, and interference is prevented. The balance weight 124 is disposed on the housing 12 at a position symmetrical to the pawl 152, so as to ensure a smooth rotation process.

The pawl 152 has a distal end, a head end, and an arcuate surface therebetween that projects toward the limit rib 151. Pawl 152's end and spacing protruding muscle 151 butt, when the wire winding, drive rotor 13 anticlockwise rotation for the end of pawl 152 is thrown off with the spacing protruding muscle 151 of current butt, and another spacing protruding muscle 151 moves to pawl 152's end along the arc surface, and under torsional spring 153's effect, the end of pawl 152 and another spacing protruding muscle 151 butt, the continuous anticlockwise rotation of drive rotor 13 accomplish the wire winding.

The housing 12 includes an upper cover 121 and a lower cover 122 coupled to each other, and a knob 132 is provided at a lower end of the lower cover 122. In this embodiment, the detent 152 is rotatably provided on the lower surface of the lower cover 122, and the limit rib 151 is provided on the knob 132.

Referring to fig. 9 to 15, six limiting convex ribs 151 are circumferentially arranged along the inner side of the knob 132 at intervals, and for convenience of description, the six limiting convex ribs 151 are respectively a first limiting convex rib 1511, a second limiting convex rib 1512, a third limiting convex rib 1513, a fourth limiting convex rib 1514, a fifth limiting convex rib 1515, and a sixth limiting convex rib 1516 along the clockwise direction.

In the grass mowing state, the knob 132 is driven to rotate through the rotation of the wire spool 131, the lower cover 122, the upper cover 121 and the grass mowing line 14 are driven to rotate through the matching of the pawl 152 and the limiting convex rib 151, grass mowing is achieved, therefore, the pawl 152 and the limiting convex rib 151 are always in the abutting state, namely, the sum of the torque of the wire spool and the torque of the torsion spring 153 is larger than the torque of the pawl 152, and of course, the directions of the torque of the wire spool and the torque of the torsion spring 153 are opposite to the direction of the torque of the pawl 152, namely

The grass mowing state is divided into three stages, namely a startup stage, an operation stage and a shutdown stage. Before starting up, the torque of the winding shaft is 0, the torque of the pawl 152 is 0, and the torque of the torsion spring 153 is greater than 0, so that the above conditions are met, and the tail end of the pawl 152 is in a butt joint state with the sixth limiting convex rib 1516; in the startup stage, when the motor 16 drives the winding disc 131 to rotate, in this embodiment, the winding disc 131 rotates clockwise, the rotation speed of the pawl 152 is increased, the winding shaft is subjected to the driving force of the motor 16 and the centrifugal force of the grass mowing rope to generate clockwise torque, and the torque acts on the pawl 152 and is greater than the torque of the pawl 152, so that the tail end of the pawl 152 and the sixth limiting convex rib 1516 are in a butt joint state; in the operation stage, the force is not changed, and the pawl 152 is still abutted against the sixth limiting convex rib 1516; in the stopped state, the rotation speed of the wire spool 131 gradually decreases, the centrifugal force applied to the pawl 152 gradually decreases, and the pawl 152 is not enough to overcome the force of the wire spool 131 on the pawl 152, and the pawl 152 and the sixth limit rib 1516 are in contact with each other all the time.

Referring to fig. 9 to 13, when the line is paid off by knocking, the grass-mowing head intermittently knocks the ground, so that the rotating body 13 is instantly stalled and the rotating speed is instantly restored, and the line is paid off by the relative rotation of the rotating body 13 and the casing 12; when the rotating body 13 contacts the ground, that is, the knob 132 contacts the ground, and stalls instantaneously, the lower cover 122 continues to rotate clockwise under the action of inertia of the casing 12, so that the tail end of the pawl 152 is disengaged from the sixth limiting convex rib 1516, and the pawl 152 rotates counterclockwise under the action of centrifugal force, so that the pawl 152 is completely disengaged from the sixth limiting convex rib 1516; when rotor 13 leaves ground, the rotational speed resumes, rotor 13 clockwise rotation, the striking that the head end of pawl 152 received first spacing protruding muscle 1511 makes the terminal perk of pawl 152 and with the butt of the spacing protruding muscle 1515 of fifth, and then make pawl 152 and the butt of the spacing protruding muscle 1515 of fifth originally with the butt of the spacing protruding muscle 1516 of sixth, take place relative motion between rotor 13 and the casing 12, accomplish a unwrapping wire. Multiple payouts can be accomplished by multiple strokes as needed until the desired length of the line 14 is achieved.

Referring to fig. 13 to 15, during winding, the wire spool 131 or the knob 132 is driven to rotate counterclockwise, so that the fifth limiting convex rib 1515 is disengaged from the tail end of the pawl 152, the sixth limiting convex rib 1516 rotates to the tail end of the pawl 152 and extrudes the pawl 152, the torsion spring 153 is extruded, the sixth limiting convex rib 1516 rotates to one side of the tail end of the pawl 152, under the effect of the torsion spring 153, the tail end of the pawl 152 tilts and abuts against the sixth limiting convex rib 1516, so that the pawl 152 which is abutted against the fifth limiting convex rib 1515 is abutted against the sixth limiting convex rib 1516, relative movement occurs between the rotor 13 and the casing 12, and one section of winding is completed. During the winding process, the spool 131 or the knob 132 is continuously rotated so that the mowing line 14 is wound on the spool 131. The motor 16 may drive the wire spool 131 to perform automatic winding, or the manual driving knob 132 may drive the manual winding, which is not limited herein.

Example two

Fig. 16 to 18 show a second embodiment, wherein the same or corresponding parts as in the first embodiment are provided with the same reference numerals as in the first embodiment. For simplicity, only the differences between the second embodiment and the first embodiment will be described. The difference is that the pawl 252 is rotatably disposed on the lower surface of the upper cover 221, the rotating body includes a driving seat 233, the driving seat 233 is connected to the upper end of the wire spool 231, and the limiting rib 251 is disposed on the driving seat 233.

Further, the knob 232 is connected to and coaxially disposed with the wire spool 231. The upper cover 221 is provided with a cylindrical protrusion 223, and the pawl 252 is rotatably sleeved on the cylindrical protrusion 223. The balance weights 224 are disposed at positions of the upper cover 221 symmetrical to the pawls 252, so that a smooth rotation process can be ensured.

In a grass mowing state, the transmission seat 233 is driven to rotate through rotation of the wire spool 231, the upper cover 221, the lower cover 222 and the grass mowing line are driven to rotate through matching of the pawl 252 and the limiting convex rib 251, grass mowing is achieved, and the pawl 252 and the limiting convex rib 251 are always in a butt joint state; the principle of tapping and wire winding is the same as that of the first embodiment, and the description is omitted here.

The foregoing embodiments are merely illustrative of the principles and features of this invention, and the invention is not limited to the embodiments described above, but rather, is susceptible to various changes and modifications without departing from the spirit and scope of the invention, as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A grass trimmer comprises a handle and a grass trimming head, wherein the grass trimming head comprises a shell and a rotor rotationally connected with the shell, and is characterized by further comprising a limiting mechanism used for limiting the rotor to enable the rotor to rotate in a single direction relative to the shell;

The stop gear includes:

the pawl is rotationally arranged on the shell; the pawl has a tail end, a head end and an arc surface located between the tail end and the head end, and the arc surface protrudes toward the limit convex rib;

the two ends of the torsion spring are respectively connected with the pawl and the shell, and the torsion spring is configured to enable the tail end of the pawl to abut against one limiting convex rib;

the rotating body comprises a wire spool positioned in the shell and a knob rotatably connected with the shell, and the knob is connected with the wire spool and coaxially arranged;

the shell comprises an upper cover and a lower cover which are connected with each other, and the knob is arranged at the lower end of the lower cover;

2. The lawnmower of claim 1, wherein the rotor further comprises a connecting sleeve located within the housing and connecting the knob to the spool.

3. The lawnmower of claim 2, wherein the connection sleeve is connected to the knob by a screw, the connection sleeve being clamped to the spool.

4. The grass trimmer according to claim 1, wherein the pawl is arranged on the lower surface of the upper cover, the rotor further comprises a transmission seat, the transmission seat is connected to the upper end of the wire spool, and the limiting convex rib is arranged on the transmission seat.

5. A lawnmower according to any one of claims 1 to 4, wherein the housing is provided with a cylindrical projection, the pawl is rotatably mounted on the cylindrical projection, one end of the torsion spring is embedded in the pawl, the other end of the torsion spring is embedded in the housing, and part of the torsion spring is wound around the cylindrical projection.

6. A lawnmower according to claim 5, wherein the housing is provided with counterbalances symmetrically positioned with respect to the pawl.

7. A lawnmower according to any one of claims 1 to 4, wherein the pawl contacts at most one of the limiting ribs during rotation of the rotor.

8. A lawnmower according to any one of claims 1 to 4, wherein the sum of the torque of the rotor and the torque of the torsion spring is greater than the torque of the pawl when the end of the pawl abuts one of the limiting ribs.