CN215548421U

CN215548421U - Electric hand tool

Info

Publication number: CN215548421U
Application number: CN202022996549.4U
Authority: CN
Inventors: 哈利·索默; 沃伦·布朗; 格雷厄姆·格哈德; 庞晓丽; 鲁义刚
Original assignee: Positec Power Tools Suzhou Co Ltd
Current assignee: Positec Power Tools Suzhou Co Ltd
Priority date: 2019-12-13
Filing date: 2020-12-14
Publication date: 2022-01-18
Anticipated expiration: 2030-12-14
Also published as: CN113001481A; WO2021115207A1; CN215548422U; CN112975861A; CN215548423U

Abstract

The utility model provides a hand-held tool. The hand-held tool comprises a tool body, wherein the tool body comprises a shell, a motor and a switch element for controlling the motor, a handle is formed on one part of the shell, the motor is a brushless motor, the brushless motor comprises a stator, a rotor and an output shaft, the rotor is arranged on the outer side of the stator, the output shaft is arranged on the rotor, an opening is formed in the shell, and at least part of the rotor is exposed out of the opening. The hand-held tool handle extends along the direction vertical to the axis of the output shaft, the tool speed is controlled by the battery pack, the gear-free speed reduction and main shaft locking structure is adopted, and the accessory is directly connected with the output shaft.

Description

Electric hand tool

Technical Field

The utility model relates to an electric hand-held tool, in particular to an electric hand-held tool with an outer rotor motor.

Background

A common electric handheld tool generally has a speed reducing mechanism, a spindle lock and other structures, so that the overall size and mass of the electric handheld tool are large; moreover, many electric hand-held tools use an inner rotor motor as a driving unit, and when the tool is stopped, a user can only wait for the inner rotor to naturally stop rotating, but the manual intervention of the rotor stopping is difficult; in addition, the centerline of the handle of many power hand tools, particularly small angle grinders and the like, is generally parallel to the axis of the output shaft, so that the cutting force of the tool is perpendicular to the handle during operation, and when a jam occurs during cutting, it is almost difficult to control the machine to stop, thereby straining the wrist. In view of the above, there is a need to improve the existing electric handheld tool in terms of large size, heavy weight, difficulty in stopping machine, and safety.

SUMMERY OF THE UTILITY MODEL

The utility model provides an electric hand tool which is easy to operate.

The above purpose is realized by the following technical scheme:

a power hand tool having: the tool body comprises a shell and a motor; a switching element for controlling the motor; a portion of the housing forming a handle; the motor is a brushless motor, the brushless motor comprises a stator, a rotor arranged outside the stator and an output shaft arranged on the rotor, the shell is provided with an opening, at least part of the rotor is exposed out of the opening, and when the motor is in a safe state, the rotor can be manually operated through the opening.

In one embodiment, the motor has a longitudinal axis extending along the output shaft, and the handle extends in a direction perpendicular to the longitudinal axis.

In one embodiment, the output shaft is used for matching with a working head, the working head comprises a disk-shaped cutting blade or sanding element, and the disk-shaped cutting blade or sanding element is vertically arranged on the output shaft.

In one embodiment, the working head diameter d2 is at most 40mm, at least between 22mm and 35mm, preferably 28mm or 30 mm.

In one embodiment, the handle is provided with a handle center line, the distance L1 between the handle center line and the end face of the working head is 0-30mm, and the overall size of the tool is small.

In one embodiment, the distance L2 between the outer surface of the shell along the axial direction of the output shaft and the end surface of the working head is 0-40mm, so that the overall size of the tool is small.

In one embodiment, the output shaft is provided with an internally threaded mating portion, and the working head is engaged with the internally threaded mating portion through a screw provided with an external thread so as to be fastened to the output shaft.

In one embodiment, the electric hand tool comprises a shield detachably connected with the shell, the shield is used for accommodating at least part of the working head, the shield is provided with a through hole, the edge of the through hole is provided with at least one protrusion facing the output shaft in the radial direction, the shell is provided with a tail end close to the working head, the tail end is provided with a groove facing the output shaft in the radial direction, and the protrusion of the shield can axially penetrate through the groove of the shell, so that the shield and the shell can be fixed and separated.

In one embodiment, the handle has a handle centerline, and the motor housing outer diameter surface is between 11mm and 17mm from the motor axis in the direction of the handle centerline at a distance L3.

In one embodiment, the power hand tool further comprises a switch element for controlling the motor, the switch element comprising a switch trigger rotatably arranged relative to the housing, rotation of the switch trigger causing the switch element to transition from a first state to a second state to activate the motor.

In one embodiment, the power hand tool is selectively coupled to a battery pack or connected to an external AC power source.

In one embodiment, the electric hand tool is connected with the battery pack or external alternating current through the adapter, and the switch element is arranged on the adapter and can control the motor to start and stop.

In one embodiment, the electric hand tool is connected with the battery pack or external alternating current through the adapter, and the adapter is provided with a speed regulating button which is used for regulating the speed of the motor.

In one embodiment, the electric hand tool speed n is at least 18000rpm and at most 40000 rpm.

In one embodiment, the power hand tool weighs between 70g and 180g, preferably between 110g and 120 g.

In one embodiment, the circumference C of the handle is between 70mm and 120mm, and is particularly preferably 100 mm.

In one embodiment, the electric hand tool motor diameter d1 is between 17mm and 28 mm.

In one embodiment, the handle has a handle centerline that makes an angle α with the motor axis of between 0 degrees and 135 degrees, preferably an angle α of 90 degrees.

In one embodiment, the distance h between the outer surface of the housing in the axial direction of the output shaft and the end of the output shaft is at least between 38mm and 55mm, and particularly preferably 45 mm.

In one embodiment, the handle has a handle centre line, and the length L of the power hand tool in the direction of the handle centre line is between 130mm and 200mm, particularly preferably 170 mm.

The utility model has the beneficial effects that: the electric hand-held tool adopts the outer rotor brushless motor, the motor is positioned in the shell, the shell is provided with the opening, and at least part of the outer rotor is exposed out of the opening, so that the output shaft of the tool can stop rotating through manual operation when the speed of the rotor is low in the tool stopping process, the outer rotor can be manually held without a main shaft lock mechanism when a working head is installed, accessories are convenient to install, and the heat dissipation of the motor is good; the working head of the electric hand-held tool is directly connected with the output shaft, the structural design is simple and ingenious, and structures such as gear transmission, spindle lock and the like do not exist, so that the tool is integrally miniaturized, the integral mass of the tool is greatly reduced, the operation is light and handy, and the tool is convenient to carry; the handle of the electric hand-held tool extends along the direction vertical to the longitudinal axis of the motor, so that the cutting force of the tool is along the force application direction of the handle in the cutting working process, when the cutting is blocked, the arm can more easily resist the cutting resistance, the occurrence of accidents is reduced, and the operation is safer and more reliable; the electric hand-held tool can be provided with the protective cover which is matched and connected with the shell through the inner bulge, so that the electric hand-held tool is convenient to disassemble; in addition, the electric hand-held tool can be selectively connected with the battery pack in a matching mode or connected with external alternating current through the adapter, the speed of a tool motor can be regulated through the battery pack, and the electric hand-held tool is simpler and more convenient to use.

Drawings

FIG. 1 is a cross-sectional view of a small cutting machine according to a first embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1;

FIG. 3 is a schematic structural view of a small cutting machine according to a first embodiment;

FIG. 4 is a partially exploded view of the first embodiment of the mini-cutter with the shield partially disassembled;

FIG. 5 is a schematic view of the mounting structure of FIG. 4 with the working head attached;

fig. 6 is a partial structural schematic view of the small sander of the second embodiment.

FIG. 7 is a schematic diagram of the first embodiment of the tool with power applied thereto;

elements in the drawings are numbered as follows:

100. electric hand tool 110, housing 111, and handle

112. The shell is close to the working head 120 and the rotor along the axis 113 of the output shaft

End of the outer surface of the direction

121. Output shaft 130, switch 131, toggle switch

140. Shield 141, cutting blade 142, gasket

143. Screw 150, sanding member 122, fan

1401. Shroud through hole 1402, shroud boss 1131 housing opening

1132. Case recess 1133, case mounting part 160, and battery pack

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the electric hand tool of the present invention is further described in detail by embodiments in the following with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting of the utility model.

Referring to fig. 1 to 3, the electric hand tool of the first embodiment of the present invention is a small cutter having: the tool body 100, the tool body 100 includes a housing 110, a part of the housing 110 forms a handle 111, another part of the housing 110 is used for accommodating a motor, the outer surface 112 of the housing along the axial direction of an output shaft and a tip 113 of the housing near a working head are provided, the motor is a brushless motor and includes a stator (not shown in the figure), a rotor 120 arranged outside the stator and an output shaft 121 arranged on the rotor 120, a part of the housing 110 accommodating the motor has a housing opening 1131 (as shown in fig. 4), the rotor 120 is at least partially exposed out of the housing opening 1131 of the housing 110, so that during the tool shutdown process, the motor is in a safe state, the rotor 120 can be manually operated through the housing opening 1131, the safe state refers to that the rotor stops rotating through manual operation when the speed of the rotor is low or the tool shutdown process, the tool output shaft can be stopped by manually holding the outer rotor during the installation of the working head, the working head is convenient to mount, and meanwhile, the motor part is exposed out of the shell, so that the heat dissipation is good.

The motor has a longitudinal axis extending along the output shaft 121, and the handle 111 formed by the housing 110 extends in a direction perpendicular to the longitudinal axis, so that the cutting force F of the tool is aligned with the handle during the cutting operation, and when the cutting is blocked, the arm can more easily resist the cutting resistance, accidents are reduced, and the operation is safer and more reliable.

The output shaft 121 arranged on the rotor 120 is directly connected with the fan 122 and the working head in a matching mode, and the middle of the output shaft is free of structures such as gear transmission and spindle lock, so that the overall size of the tool is small, the overall weight is light, and the tool is convenient for an operator to carry and use; the electric hand tool 100 can be matched and connected with different working heads, and comprises a disc-shaped cutting blade 141 or a sanding element 150 (shown in fig. 6), wherein the disc-shaped cutting blade 141 or the sanding element 150 is vertically arranged on the output shaft 121, an internal thread is arranged at one end of the output shaft 121, the working head cutting blade 141 and the gasket 142 can be directly fastened on the output shaft 121 through a screw 143 matched and connected with the internal thread, and the working heads are convenient to detach.

The handle 111 has a handle centerline defining the handle centerline as the centerline of the handle's largest profile cross-section, the handle centerline being located a distance L1 between 0 and 30mm from the working head end face, and when L1 is 0, the electric hand tool 100 is a straight shank type hand tool.

The other part of the housing 110 for accommodating the motor has an outer surface 112 of the housing along the axial direction of the output shaft, the distance L2 between the outer surface 112 and the end surface of the working head is 0-40mm, and the handle 111 can be located at the middle position or the lower position (not shown in the figure) of the housing for accommodating the motor, namely the dotted line part in FIG. 1 can be located at any position along the longitudinal axis direction of the motor.

The electric hand tool 100 has a switch element for controlling the motor, the switch element is a switch trigger 130 rotatably disposed with respect to the housing, the rotation of the switch trigger 130 operates the toggle switch 131 to switch from the first state to the second state to start the motor, and the rotation of the switch trigger 130 operates the toggle switch 131 to switch from the second state to the first state to stop the motor.

Referring to fig. 1, the geometry of the motor is defined by the diameter of the motor, the motor diameter d1 being between 17mm and 28mm, which will vary somewhat during manufacture, and the motor housing outer diameter surface being between 11mm and 17mm from the motor axis L3 in the direction of the handle centerline. In order to scale the accessory working head cutting blades 141 with the motor and the power hand tool 100 such that the tool operation is compact and efficient, the accessory working head diameter d2 is a maximum of 40mm, at least between 22mm and 35mm, preferably 28mm or 30 mm.

The motor axis and the handle centre line form an angle α with each other of 0 to 135 degrees, preferably 90 degrees, and when the angle α is 0 degrees, the electric hand tool 100 motor can be located in the handle housing and the machine tool 100 is a straight shank machine tool.

As shown in fig. 2, the distance h between the outer surface 112 of the motor housing in the axial direction of the output shaft and the end of the output shaft 121 is at least 38mm to 55mm, and particularly preferably 45 mm; as shown in fig. 3, the length L of the power hand tool 100 in the direction of the handle center line is between 130mm and 200mm, and particularly preferably 170 mm. The optimum ratio of the length L of the electric hand tool 100 to the height h1 of the motor housing is at least between 3 and 4.5, preferably 3.8.

As shown in fig. 4 and 5, when the working head is a cutting blade 141, the electric hand tool 100 has a shield 140 detachably connected to the housing 110, and the shield 140 is used for accommodating at least a part of the working head to prevent working debris from splashing to the vicinity of an operator during the working process of the tool; the shield 140 is provided with a through hole 1401, the edge of the through hole 1401 is provided with at least one protrusion 1402 facing the output shaft in the radial direction, meanwhile, the end 113 of the shell close to the working head is provided with a groove 1132 facing the output shaft in the radial direction, and the protrusion 1402 of the shield can axially penetrate through the groove 1132 of the shell; when the shield 140 is installed, the protrusion 1402 of the shield passes through the groove 1132 of the housing and then rotates, so that the through hole 1401 of the shield 140 is matched and connected with the housing installation part 1133, and the protrusion 1402 of the shield is clamped on the upper part of the housing, so that the shield can be fixed on the housing; upon removal of the shield 140, the shield 140 can be separated from the housing end 113 by rotating the shield such that the projections 1402 of the shield pass through the recesses 1132 of the housing.

Further, referring to fig. 7, the power hand tool 100 may optionally be coupled to a battery pack 160 or may be connected to an external ac power source via an adapter; in another alternative embodiment, a switch element may be disposed on the battery pack 160 or the adapter, the motor start/stop may be controlled by the switch element on the battery pack 160 or the adapter (not shown), the motor speed may be adjusted by a speed knob on the battery pack 160 or the adapter, and the speed knob may also be disposed on the housing 110 of the power hand tool 100.

In order to make the tool more comfortable to hold and more comfortable to fit the user's requirements, in the embodiment of the present invention, as shown in fig. 3, the perimeter C of the handle 111 is between 70mm and 120mm, and is particularly preferably 100 mm. The speed n of the electric hand tool 100 is at least 18000rpm and at most 40000 rpm. In addition, the power hand tool 100 of the present invention is relatively small in size and mass, and weighs between 70g and 180g, preferably between 110g and 120g, which is the total weight of the power hand tool 100 including the accessories after removing the external power cord, adapter and battery pack.

The electric hand-held tool in the utility model comprises but is not limited to a small angle grinder, and also comprises electric hand-held tools such as an electric hand-held cutting machine, a sanding machine, a polishing machine and the like.

Claims

1. A power hand tool having:

the tool body comprises a shell and a motor;

a switching element for controlling the motor;

a portion of the housing forming a handle;

the method is characterized in that: the motor is a brushless motor, the brushless motor comprises a stator, a rotor arranged outside the stator and an output shaft arranged on the rotor, the shell is provided with an opening, at least part of the rotor is exposed out of the opening, and when the brushless motor is in a safe state, the rotor can be manually operated through the opening.

2. The power hand tool according to claim 1, wherein: the output shaft is used for matching with the working head; the diameter of the working head is not more than 40 mm.

3. The power hand tool according to claim 1, wherein: the output shaft is used for matching with the working head; the handle is provided with a handle central line, and the distance L1 between the handle central line and the end surface of the working head is 0-30 mm.

4. The power hand tool according to claim 1, wherein: the handle has a handle centerline, and the motor housing outer diameter surface is located between 11mm and 17mm from the motor axis along the handle centerline direction at a distance L3.

5. The power hand tool according to claim 1, wherein: the electric hand-held tool can be selectively matched and connected with a battery pack or connected with external alternating current.

6. The power hand tool according to claim 1, wherein: the rotating speed n of the electric hand-held tool is at least 18000rpm and at most 40000 rpm.

7. The power hand tool according to claim 1, wherein: the power hand tool weighs between 70g and 180 g.

8. The power hand tool according to claim 1, wherein: the perimeter C of the handle is between 70mm and 120 mm.

9. The power hand tool according to claim 1, wherein: the distance h between the outer surface of the shell along the axial direction of the output shaft and the tail end of the output shaft is between 38mm and 55 mm.

10. The power hand tool according to claim 1, wherein: the handle has a handle centerline, and the length L of the power hand tool in the direction of the handle centerline is between 130mm and 200 mm.