CN116833958A

CN116833958A - Electric tool and electric hammer

Info

Publication number: CN116833958A
Application number: CN202210302329.8A
Authority: CN
Inventors: 韩言; 蔡建恒; 王福祥
Original assignee: Nanjing Chervon Industry Co Ltd
Current assignee: Nanjing Chervon Industry Co Ltd
Priority date: 2022-03-25
Filing date: 2022-03-25
Publication date: 2023-10-03

Abstract

The application discloses an electric tool and an electric hammer, the electric hammer comprises: a motor; a driving mechanism that generates a driving force; the impact mechanism is abutted with the top end functional piece and driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, and the output axis extends along the front-back direction of the electric hammer; the impact mechanism includes: the impact rod is abutted with the top end functional piece; the impact power piece is connected with the driving mechanism and generates impact power; the impact block is positioned between the impact rod and the impact power piece, can form a gas space with the impact power piece, and reciprocates under the impact of the impact power generated by the impact power piece so as to impact the impact rod; the specific volume of the gas in the gas space is more than or equal to 0.3 m/kg and less than or equal to 0.4 m/kg, and the impact energy density of the electric hammer is more than or equal to 23000J/min; the mass of the gas is a fixed value, and when the impact power piece moves to the forefront end along the direction of the output axis, the gas has a first gas volume, and the specific volume is the ratio of the first gas volume to the mass.

Description

Electric tool and electric hammer

Technical Field

The application relates to an impact electric tool, in particular to an electric hammer.

Background

As a widely used electric tool, an impact type electric tool such as an electric hammer or an electric pick can be used to open a hole in a hard material such as concrete, brick, stone, or the like. In the working process of the tool, the whole machine vibrates greatly, and the human engineering needs to be further lifted.

Disclosure of Invention

In order to solve the defects of the prior art, the application aims to provide an impact electric tool with small vibration of the whole machine and high impact energy density.

In order to achieve the above object, the present application adopts the following technical scheme:

an electric hammer configured to perform a hammer drilling operation through a tip function, the electric hammer comprising: a motor; a driving mechanism for generating a driving force; the impact mechanism can be abutted with the top end functional piece and can be driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, wherein the output axis extends along the front-rear direction of the electric hammer; the impact mechanism includes: the impact rod can be abutted with the top end functional piece; the impact power piece is connected with the driving mechanism and is used for generating impact power; the impact block is positioned between the impact rod and the impact power piece, can form an air space with the impact power piece, and can reciprocate under the impact of the impact power generated by the impact power piece so as to impact the impact rod; the specific volume of the gas in the gas space is larger than or equal to 0.3 m/kg and smaller than or equal to 0.4 m/kg, and the impact energy density of the electric hammer is larger than or equal to 23000J/min; the mass of the gas is a fixed value, the gas has a first gas volume when the impact power piece moves to the forefront end along the direction of the output axis, and the specific volume is the ratio of the first gas volume to the mass.

Further, the specific volume of the gas is greater than or equal to 0.3 m/kg and less than or equal to 0.36 m/kg, and the impact energy density of the electric hammer is greater than or equal to 23000J/min.

Further, the specific volume of the gas is greater than or equal to 0.3 m/kg and less than or equal to 0.4 m/kg, and the impact energy density of the electric hammer is greater than or equal to 26000J/min.

Further, the impact frequency of the electric hammer is greater than or equal to 4200BPM.

Further, the impact frequency of the electric hammer is greater than or equal to 4350 BPM.

Further, a distance between a reciprocating center line of a driving piece connected with the impact power piece in the driving mechanism in the direction of the output shaft line and the rear end surface of the impact block is less than or equal to 80mm.

An electric tool configured to perform at least an impact operation through a tip function, the electric tool comprising: a motor; a driving mechanism for generating a driving force; the impact mechanism can be abutted with the top end functional piece and can be driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, wherein the output axis extends along the front-back direction of the electric tool; the impact mechanism includes: the impact rod can be abutted with the top end functional piece; the impact power piece is connected with the driving mechanism and is used for generating impact power; the impact block is positioned between the impact rod and the impact power piece, can form an air space with the impact power piece, and can reciprocate under the impact of the impact power generated by the impact power piece so as to impact the impact rod; wherein the impact energy density of the electric hammer is greater than or equal to 23000J/min; the distance between the reciprocating center line of the driving part connected with the impact power part in the driving mechanism in the direction of the output shaft line and the rear end surface of the impact block is less than or equal to 80mm.

Further, the impact frequency of the power tool is greater than or equal to 4200BPM.

An electric tool configured to perform at least an impact operation through a tip function, the electric tool comprising: a motor; a driving mechanism for generating a driving force; the impact mechanism can be abutted with the top end functional piece and can be driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, wherein the output axis extends along the front-back direction of the electric tool; the impact mechanism includes: the impact rod can be abutted with the top end functional piece; the impact power piece is connected with the driving mechanism and is used for generating impact power; the impact block is positioned between the impact rod and the impact power piece, can form an air space with the impact power piece, and can reciprocate under the impact of the impact power generated by the impact power piece so as to impact the impact rod; wherein the impact energy density of the electric hammer is greater than or equal to 23000J/min, and the impact frequency of the electric tool is greater than or equal to 4200BPM.

Further, the impact frequency of the electric tool is greater than or equal to 4350 BPM.

The beneficial effects are that: the electric hammer with low high frequency impact power, low vibration of the whole machine, smaller volume and better man-machine engineering is realized.

Drawings

Fig. 1 is a structural view of an electric hammer in an embodiment of the present application;

FIG. 2 is a view showing the internal structure of the electric hammer shown in FIG. 1 with a housing removed;

FIG. 3 is a cross-sectional view of the electric hammer of FIG. 1;

FIG. 4 is a block diagram of an electric hammer in one embodiment of the present application;

FIG. 5 is a view showing the internal structure of the electric hammer shown in FIG. 4 with a housing removed;

FIG. 6 is a view showing the internal structure of the electric hammer shown in FIG. 4 with a housing removed;

fig. 7 is a cross-sectional view of the electric hammer shown in fig. 4.

Reference numerals:

1-an electric hammer; 10-a power interface; 11-a housing; 111-a grip; 112-a first receptacle; 113-a second receptacle;

a 2-motor; 21-a motor body; 22-motor shaft; 23-a first motor drive gear; 24-a second motor drive gear;

3-a driving mechanism; 31-a first drive assembly; 311-a first drive shaft; 312-a first transmission gear; 313-a first drive gear; 32-a second drive assembly; 321-a second drive shaft; 322-a second transmission gear; 323-swing rod bearing; 33-a third drive assembly; 331-a third drive shaft; 332-a third drive gear; 333-third drive gear; 34-a fourth drive assembly; 341-crank rocker; 35-a support;

4-an impact mechanism; 41-an impact bar; 42-an impact block; 43-impact power member; 431-piston; 432-a connector; 433-cylinder; 44-gas space;

5-an output mechanism; 51-sleeve; 52-sleeve drive wheel; 521-a first sleeve drive wheel; 522-a second sleeve drive wheel; 53-air holes;

6-top end function;

7-a clamping assembly;

8-a secondary handle;

an A-output axis; b-motor axis; distance between the L-reciprocating center line and the rear end face of the impact block.

Detailed Description

The following describes the real-time mode of the present application with reference to the drawings. In the following real-time system, an electric hammer is shown as an example of a power tool configured to operate by driving a tip function. Other impact type power tools, such as picks, are also within the scope of the present application and are not specifically recited herein.

The electric hammer is configured to reciprocate a tip functional element mounted on a tool linearly in an output axis direction, rotate around the output axis direction, or perform both of the operations.

First, the overall structure of the electric hammer will be described. For clarity of explanation of the technical solution of the present application, upper, lower, front and rear are defined as shown in fig. 1 and 4.

As shown in fig. 1 and 4, the outer contour of the electric hammer 1 is mainly composed of a housing 11, the housing 11 is formed with a grip portion 111, and an accommodation space capable of containing various functional components is formed inside the housing 11.

Referring to fig. 1 to 4, the electric hammer 1 mainly includes a housing 11, a power source interface 10, a motor 2, a driving mechanism 3, an impact mechanism 4, and an output mechanism 5. In one embodiment, the power interface 10 can be connected to a battery pack, and the battery pack and the housing 11 can be connected in a plugging manner or can be separated, that is, the battery pack is not directly mounted on the surface of the housing 11, and the specific mounting manner is not limited herein, so long as the power source can be provided. In one embodiment, the power interface 10 is capable of accessing ac mains.

The housing 11 is formed with a grip portion 111 for a user to grip, a first accommodating portion 112 accommodating the motor 2 and the driving mechanism 3, and a second accommodating portion 113 accommodating the impact mechanism 4 and the output mechanism 5. As shown in fig. 1 and 4, to more clearly illustrate the design positions of the different structures, an output axis a is defined. In one embodiment, the output axis a is substantially parallel to or collinear with a line along which the tip functional component 6 is mounted, the second accommodating portion 113 extends along the output axis a, and the first accommodating portion 112 and the second accommodating portion 113 are integrally formed in a substantially "T" shape when viewed from the side. In one embodiment, the first accommodating portion 112 may extend along the output axis a, and the first accommodating portion and the second accommodating portion 113 may be formed in a substantially rectangular shape when viewed from the side.

The motor 2 includes a motor main body 21 and a motor shaft 22. The motor axis B on which the motor shaft 22 is located has an angle with the output axis a, which is greater than or equal to 0 ° and less than or equal to 180 °. In one embodiment, the motor axis B is at approximately 90 ° to the output axis a. In one embodiment, motor axis B is substantially parallel to output axis a.

The output mechanism 5 includes: the sleeve 51, the sleeve 51 being drivable by the drive mechanism 3 for rotation about the output axis a. Specifically, the sleeve 51 is formed with a housing cavity for housing the tip functional element 6, and the tip functional element 6 can be inserted into the housing cavity. The clamping assembly 7 may retain the tip function 6 within the sleeve 51. When the sleeve 51 rotates about the output axis a, the tip function 6 can be driven to rotate. In one embodiment, a sleeve driving wheel 52 is fixed to the outer side of the sleeve 51, and the sleeve driving wheel 52 can be driven by the driving mechanism 3, so as to rotate the sleeve 51.

The impact mechanism 4 can be driven by the driving mechanism 3 to drive the top end functional piece 6 to reciprocate along the direction of the output axis A. In the present embodiment, the impact mechanism 4 includes an impact lever 41, an impact block 42, and an impact power member 43. The impact lever 41 can abut against the tip functional element 6. That is, after the tip functional member 6 is inserted into the sleeve 51 from front to back in the direction of the output axis a, it can be brought into contact with the front end surface of the impact block 42. The position of the impact rod 41 within the sleeve 51 is substantially constant. An impact block 42 is provided at the rear end of the impact rod 41, and is capable of reciprocally impacting the impact rod 41 from rear to front in the direction of the output axis a under the urging of impact power. When the impact block 42 is in the impact position, the impact rod 41 can transmit the impact force to the tip functional element 6, so that the tip functional element 6 performs the impact action on the workpiece. The impact power member 43 is disposed behind the impact block 42, and one end of the impact power member 43 is connected to the driving mechanism 3, and can be driven by the driving mechanism 3 to generate impact power.

In this embodiment, a gas space 44 can be formed between the impact block 42 and the impact power member 43. The impact power member 43 is driven by the driving mechanism 3 to compress the gas in the gas space 44, and the pressure of the gas in the gas space 44 is increased, thereby generating impact power. That is, when the impact power member 43 is driven by the driving mechanism 3, it can move from back to front along the direction of the output axis a to compress the gas in the gas space 44, and the size of the corresponding gas space 44 will also change. When the gas pressure in the gas space 44 is sufficiently high, the impact block 42 can be pushed to impact in the direction in which the impact rod 41 is located. Specifically, the length of the air space 44 in the direction of the output axis a is continuously reduced during the movement of the impact power member 43 from back to front, and the impact block 42 moves to the impact position when the impact block 42 impacts the impact lever 41. The length of the gas space 44 above the output axis a is minimal when the impact block 42 is in the impact position.

The driving mechanism 3 is disposed in the first accommodating portion 112, and can drive the output mechanism 5 to drive the top end functional piece 6 to perform drilling operation, or drive the impact mechanism 4 to drive the top end functional piece 6 to perform impact operation, or drive the output mechanism 5 and the impact mechanism 4 to simultaneously perform hammer drilling operation on the top end functional piece 6. In alternative implementations, the driving mechanism 3 may be matched with other clutch structures or control structures or switching structures to selectively control the output mechanism 5 or the impact mechanism 4, and specific implementations are not described in detail in this embodiment.

In one embodiment, the drive mechanism 3 comprises a first drive assembly 31 and a second drive assembly 32. The first drive assembly 31 is for driving the output mechanism 5 and the second drive assembly 32 is for driving the impact mechanism 4. Referring to fig. 2 and 3, the first driving assembly 31 includes a first driving shaft 311, a first transfer gear 312, and a first driving gear 313; the second driving assembly 32 includes a second driving shaft 321, a second transfer gear 322, a second driving gear 323, and an eccentric shaft 324. Wherein the first driving shaft 311 is approximately parallel to the motor shaft 22 and the second driving shaft 321 in the vertical direction. The motor shaft 22 is provided with a first motor transmission gear 23, and the first motor transmission gear 23 can be meshed with the first transmission gear 312 and the second transmission gear 322, respectively. The motor rotates to drive the first motor rotating gear 23 to rotate, the first motor driving gear 23 drives the first driving gear 312 and the second driving gear 322 to rotate, and then the first driving gear 312 drives the first driving shaft 311 to rotate, and the second driving gear 322 drives the second driving shaft 321 to rotate. Further, the rotation of the first driving shaft 311 drives the first driving gear 313 to rotate, and the first driving gear 313 is meshed with the first sleeve driving wheel 521 fixed outside the sleeve 51, so that the first sleeve driving wheel 521 can drive the sleeve 51 to rotate, and the top functional piece 6 can perform drilling operation. In addition, the rotation of the second driving shaft 321 can rotate the second driving gear 323, so that the eccentric shaft 324 provided on the second driving gear 323 can reciprocate in the front-rear direction. Since the eccentric shaft 324 is connected to the impact power member 43, the impact power member 43 can generate impact power to reciprocate the tip functional member 6 in the direction of the output axis a. In one embodiment, the first driving gear 313 is a bevel gear with which the first sleeve driving wheel 521 fixed outside the sleeve 51 can be engaged, thereby changing the transmission direction.

In one embodiment, the eccentric shaft 324 is directly connected to the impact power member 43, and the eccentric shaft 324 may then act as a drive member in the drive mechanism 3 that is connected to the impact power member 43.

In one embodiment, the distance between the reciprocation centerline C of the eccentric shaft 324 in the direction of the output axis A and the rear end face of the impact block 42 is less than or equal to 80mm. Referring to fig. 2 and 3, eccentric shaft 324 has a first position when rotated to the foremost end and a second position when rotated to the rearmost end. The line perpendicular to the output axis a, where the center point of the line connecting the first position and the second position in the direction parallel to the output axis a is located, is the reciprocation center line C of the eccentric shaft 324. For example, referring to fig. 2, the first position is located on a first position line C1 perpendicular to the output axis a, and the second position is located on a second position line C2 perpendicular to the output axis a, and a line parallel to and equidistant from the first position line C1 and the second position line C2 is the reciprocation center line C. The distance from the reciprocation center line C to the rear end face of the impact block 42 is L with reference to fig. 3. In this embodiment, L.ltoreq.80 mm.

In one implementation, the distance L is continuously changed and is 80mm at maximum when the eccentric shaft 324 reciprocates the impact power 43 in the direction of the output axis a. Due to the mass m=pi R of the gas in the gas space 44 ² Lρ ⁰ Where R is the radius of the gas space 44, which can also be considered as the radius of the cylinder 433 or the radius of the sleeve 51, L is the distance between the reciprocation centerline C and the rear end face of the impact block 42, ρ ⁰ The air density of the working temperature is below 140 ℃ and is 0.915kg/m ³ . In one implementation, the specific volume Ve of the gas in the gas space 44 is the ratio of the volume of the gas in the gas space 44 to the mass, i.e., ve=v/m.

In the embodiment of the present application, the mass of the gas in the gas space 44 is substantially unchanged and may be regarded as a fixed value m1, whereas the gas has a first gas volume V1 when the impact power member 43 moves to the forefront in the direction of the output axis a. Where m1 may be the mass of the gas in the gas space 44 when the impact power member 43 is rearmost in the direction of the output axis a. In the case of an AC electric hammer having a bare metal weight of 4KG or more or a DC electric hammer having a bare metal weight of 3KG or more, the temperature in the cylinder 433 near the rear end face of the impact block 42 is about 120 °, and if the operating environment temperature of the electric hammer is 20 °, the temperature in the cylinder 433 near the rear end face of the impact block 42 is about 140 °. Under the above conditions, the specific volume of the gas in the gas space 44, ve1=v1/m 1, and the value of Ve1 ranges from 0.3m to 0.4 m.

In one embodiment, the impact energy density of the electric hammer 1 is greater than or equal to 23000J/min based on a specific volume of gas Ve1 in the gas space 44 of greater than or equal to 0.3 m/kg and less than or equal to 0.4 m/kg. For example, the impact energy density of the electric hammer 1 is 23500J/min, 24000J/min, 24500J/min, 25000J/min, 25500J/min, 26000J/min, and the like.

In one embodiment, the impact energy density of the electric hammer 1 is greater than or equal to 23000J/min based on a specific volume of gas Ve1 in the gas space 44 of greater than or equal to 0.3 m/kg and less than or equal to 0.36 m/kg. For example, the impact energy density of the electric hammer 1 is 23500J/min, 24000J/min, 24500J/min, 25000J/min, 25500J/min, 26000J/min, and the like.

In one embodiment, the impact energy density of the electric hammer 1 is greater than or equal to 26000J/min based on a specific volume of gas Ve1 in the gas space 44 of greater than or equal to 0.3 m/kg and less than or equal to 0.4 m/kg. For example, the impact energy density of the electric hammer 1 is 26500J/min, 27000J/min, 27500J/min, or the like.

In one embodiment, the impact frequency of the electric hammer 1 is greater than or equal to 4200BPM, such as 4300 BPM,4400BPM,4500BPM, on the basis of an impact energy density greater than or equal to 23000J/min.

In one embodiment, the impact frequency of the electric hammer 1 is greater than or equal to 4350BPM, such as 4400BPM,4450BPM,4500BPM impact frequency, on the basis of an impact energy density greater than or equal to 23000J/min.

In one embodiment, the distance between the center line C of reciprocation of the eccentric shaft 324 in the direction of the output axis A and the rear end face of the impact block 42 is less than or equal to 80mm on the basis of the impact energy density being greater than or equal to 23000J/min.

In one embodiment, the motor shaft 22 further includes a support member 35, which is disposed on the motor shaft and is capable of supporting the first driving assembly 31 and the second driving assembly 32 so as to be located at the upper end of the motor 2.

Referring to fig. 2 and 3, the impact power member 43 includes a piston 431 and a connecting member 432 fixed to the piston 431, a front end of the connecting member 432 being fixed to the piston 431, a rear end of the connecting member 432 being connected to the eccentric shaft 324. Thus, when the second driving shaft 321 rotates to drive the eccentric shaft 324 to reciprocate in the front-rear direction, the connecting piece 432 also drives the piston 431 to reciprocate in the sleeve 51. In the present embodiment, a gas space 44 can be formed between the front end surface of the piston 432 and the rear end surface of the impact block 42. It will be appreciated that when eccentric shaft 324 is closest to sleeve 51, piston 431 is furthest from the rear end of sleeve 51; when eccentric shaft 324 is furthest from sleeve 51, piston 431 is closest to the rear end of sleeve 51. During forward movement of piston 431 away from the rear end of sleeve 51, the gas in gas space 44 is compressed and the gas pressure increases, pushing impact block 42 forward to the impact position. During the movement of piston 431 toward the rear end of sleeve 51, the gas pressure in gas space 44 gradually decreases, creating a negative pressure, so that impact block 42 moves back out of the impact position. The above-described process is a process in which the impact mechanism 4 completes one impact action and resets. In the present embodiment, the rear end surface of the impact block 42, the inner side wall of the sleeve 51, and the front end surface of the piston 431 can form the above-described gas space 44. Alternatively, the gas space 44 may be a closed space or a non-closed space, for example, an air hole 53 is left on the wall of the sleeve 51, and the air hole 53 can provide a gas exchange channel for the gas space 44 and a space outside the sleeve 51 during the movement of the piston 431, so as to reduce the serious heat generation problem caused by the repeated reciprocation of the piston 431.

In one embodiment, the construction of the electric hammer is shown in fig. 4 to 7. The electric hammer shown in fig. 4 to 7 is mainly different from the electric hammer shown in fig. 1 to 3 in the driving mechanism 3 and the impact power mechanism 4. Therefore, in this embodiment, the other structures will not be described in detail. Wherein fig. 4-7 follow the reference numerals of fig. 1-3, i.e. like parts are given like reference numerals.

In one embodiment, the drive mechanism 3 includes a third drive assembly 33 and a fourth drive assembly 34. The third drive assembly 33 is used to drive the output mechanism 5 and the fourth drive assembly 34 is used to drive the impact mechanism 4. Referring to fig. 5 to 7, the third driving assembly 33 includes a third driving shaft 331, a third transmission gear 332, and a third driving gear 333; the fourth drive assembly 34 includes a rocker 341 disposed on the third drive shaft 331. The rocker 341 is directly connected with the impact power piece 43, can drive the impact power piece 43 to move, and the rocker 341 can be used as a driving piece connected with the impact power piece 43 in the driving mechanism 3.

In one embodiment, the third drive shaft 331 is integrally formed with the motor shaft 22 to be substantially perpendicular in side view. A second motor transmission gear 24 is provided at the upper end of the motor shaft 22, and the second motor transmission gear 24 can be engaged with a third transmission gear on the third driving shaft 331, so that the third driving shaft 331 is driven to rotate when the motor rotates. In the present embodiment, the third driving shaft 331 is provided with a third transmission gear 332, a rocker 341, and a third driving gear 333 from the rear to the front. After the third driving shaft 331 is driven to rotate, the rocker 341 is driven to reciprocate in the direction of the output axis a, and since the rocker 341 is connected to the impact power member 43, the impact power member 43 can generate impact power, so that the top functional member 6 reciprocates in the direction of the output axis a. The third driving gear 333 is engaged with a second sleeve driving wheel 522 fixed outside the sleeve 51, thereby enabling the sleeve 51 to be driven to rotate. In the present embodiment, the second motor drive gear 24 is a bevel gear with which the third drive gear 332 can mesh, thereby enabling a change in the drive direction.

Referring to fig. 5 to 7, the impact power member 43 includes a cylinder 433. The cylinder 433 is a semi-closed cavity with one end open. Specifically, in the direction along the output axis a, the rear end of the cylinder 433 is a closed end and can be connected to the rocker 341, and the front end of the cylinder 433 is an open end for accommodating the impact block 42. In the present embodiment, the air cylinder 433 is connected to the tele-lever 341, and when the tele-lever 341 is driven to reciprocate in the direction of the output axis a, the air cylinder 433 is driven to reciprocate. During the forward movement of the air cylinder 433, the air in the air space 44 is compressed, the air pressure increases, and when the air pressure increases to a certain extent, the impact block 42 is pushed forward to impact to the impact position; during the rearward movement of the air cylinder 433, the air pressure in the air space 44 gradually decreases to a negative pressure state, and the impact block 42 is driven to move rearward to leave the impact position. The above-described process is a process in which the impact mechanism 4 completes one impact action and resets. In the present embodiment, the rear end surface of the impact block 42 and the inner wall of the cylinder 433 can form a gas space 44, wherein the inner wall of the cylinder 433 mainly includes a side wall and an inner wall of the rear end of the cylinder 433. The gas space 44 may be a closed space or a non-closed space, for example, a gas hole 53 is left on the wall of the cylinder 433, and the gas hole 53 can provide a gas exchange channel for the space outside the cylinder 433 and the gas space 44 during the movement of the cylinder 433, so as to reduce the serious heat generation problem caused by the repeated reciprocating movement of the cylinder 433.

In one embodiment, the drive mechanism 3 shown in fig. 2 and 3 may operate in conjunction with the impact power member 43 shown in fig. 5-7; the impact power member 43 shown in fig. 2 and 3 may be operated in cooperation with the driving mechanism 3 shown in fig. 5 to 7. In the embodiment of the present application, other deformation structures of the impact power member 43 or the driving mechanism 3 may be adopted on the basis of ensuring that the air space 44 is provided between the impact power member 43 and the impact block 42.

In one embodiment, the distance between the reciprocating center line C of the tele-rod 341 in the direction of the output axis a and the rear end face of the impact block 42 is less than or equal to 80mm. Referring to fig. 6 and 7, the tele-lever 341 has a first position when swung to the foremost end and a second position when swung to the rearmost end. The line perpendicular to the output axis a, where the center point of the line between the first position and the second position in the direction parallel to the output axis a is located, is the reciprocation center line C of the tele-lever 341. For example, referring to fig. 6, the first position is located on a first position line C1 perpendicular to the output axis a, and the second position is located on a second position line C2 perpendicular to the output axis a, and a line parallel to and equidistant from the first position line C1 and the second position line C2 is the reciprocation center line C. The distance from the reciprocation center line C to the rear end face of the impact block 42 is L with reference to fig. 7. In this embodiment, L.ltoreq.80 mm.

In one embodiment, the impact energy density of the electric hammer 1 is greater than or equal to 23000J/min based on a specific volume of gas Ve1 in the gas space 44 of greater than or equal to 0.3 m/kg and less than or equal to 0.4 m/kg. For example, the impact energy density of the electric hammer 1 is 23500J/min, 24000J/min, 24500J/min, 25000J/min, 25500J/min, 26000J/min, and the like. In the present embodiment, the specific volume Ve1 is calculated, and the restrictions on m1 and V1 are the same as those in the above embodiment.

In one embodiment, the distance between the reciprocation center line C of the tele-rod 341 in the direction of the output axis A and the rear end surface of the impact block 42 is less than or equal to 80mm on the basis that the impact energy density is greater than or equal to 23000J/min.

In the embodiment of the present application, the purpose of adjusting the distance L between the reciprocation center line C and the rear end face of the impact block 42 can be achieved by adjusting the mounting position or angle of the structure of the eccentric shaft 324 or the tele-lever 341 or the like as a driving member.

In the embodiment of the application, the impact energy density of the electric hammer can be greater than or equal to 23000J/min and the impact frequency can be greater than or equal to 4200BPM in the process of changing the specific volume of gas between 0.3m and 0.4m and the electric hammer with low impact at high frequency is realized. The shock feeling of the whole machine is reduced while the strong impact capability is ensured, and the man-machine engineering is optimized. In addition, due to the fact that the distance from the reciprocating center line to the rear end face of the impact block is small, more compact design on the structure is achieved, the length of the whole machine of the tool in the front-rear direction is reduced to a certain extent, and the size of the whole machine is shortened.

In one embodiment, the electric hammer 1 further comprises a secondary handle 8. The sub-handle 8 is detachably mounted on the tool body to assist the user in operating the electric hammer 1.

The following will show, by table 1, a comparison of the distance L between the center line C of reciprocation and the rear end face of the impact block 42, the load impact frequency of the electric hammer, and the impact energy density, in the case where the electric hammers A1 to A3 of different types in the different prior art are substantially the same as the electric hammer A4 protected by the embodiment of the present application, with other tool common constant X set.

TABLE 1

The common tool parameters selected for tools A1-A4 in Table 1 are all X, and the values or types of X are not described in detail herein.

As is evident from the comparison of the third to fifth rows in Table 1, the conventional tool has a lower impact frequency and lower impact energy density when the distance from the center line of reciprocation of the conventional tool to the rear end face of the impact block is less than 80mm. As is clear from a comparison of the second and fifth rows in table 1, the distance from the center line of reciprocation to the rear end face of the impact block in the conventional tool is not high enough in the impact frequency and the impact energy density even if it is increased to more than 80mm. Thus, as apparent from Table 1, the electric hammer of the present application can achieve a high level of both impact frequency and impact energy density when the distance from the center line of reciprocation to the rear end face of the impact block is less than or equal to 80mm.

The foregoing has shown and described the basic principles, principal features and advantages of the application. It will be appreciated by persons skilled in the art that the above embodiments are not intended to limit the application in any way, and that all technical solutions obtained by means of equivalent substitutions or equivalent transformations fall within the scope of the application.

Claims

1. An electric hammer configured to perform a hammer drilling operation through a tip function, the electric hammer comprising:

a motor;

a driving mechanism for generating a driving force;

the impact mechanism can be abutted with the top end functional piece and can be driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, wherein the output axis extends along the front-rear direction of the electric hammer;

the impact mechanism includes:

the impact rod can be abutted with the top end functional piece;

the impact power piece is connected with the driving mechanism and is used for generating impact power;

the impact block is positioned between the impact rod and the impact power piece, can form an air space with the impact power piece, and can reciprocate under the impact of the impact power generated by the impact power piece so as to impact the impact rod;

it is characterized in that the method comprises the steps of,

the specific volume of the gas in the gas space is larger than or equal to 0.3 m/kg and smaller than or equal to 0.4 m/kg, and the impact energy density of the electric hammer is larger than or equal to 23000J/min;

the mass of the gas is a fixed value, the gas has a first gas volume when the impact power piece moves to the forefront end along the direction of the output axis, and the specific volume is the ratio of the first gas volume to the mass.

2. The electric hammer as set forth in claim 1, wherein:

the specific volume of the gas is larger than or equal to 0.3 m/kg and smaller than or equal to 0.36 m/kg, and the impact energy density of the electric hammer is larger than or equal to 23000J/min.

3. The electric hammer as set forth in claim 1, wherein:

the specific volume of the gas is larger than or equal to 0.3 m/kg and smaller than or equal to 0.4 m/kg, and the impact energy density of the electric hammer is larger than or equal to 26000J/min.

4. The electric hammer as set forth in claim 1, wherein:

the impact frequency of the electric hammer is greater than or equal to 4200BPM.

5. The electric hammer as set forth in claim 1, wherein:

the impact frequency of the electric hammer is larger than or equal to 4350 BPM.

6. The electric hammer as set forth in claim 1, wherein:

the distance between the reciprocating center line of the driving part connected with the impact power part in the driving mechanism in the direction of the output shaft line and the rear end surface of the impact block is less than or equal to 80mm.

7. An electric tool configured to perform at least an impact operation through a tip function, the electric tool comprising:

a motor;

a driving mechanism for generating a driving force;

the impact mechanism can be abutted with the top end functional piece and can be driven by the driving mechanism to drive the top end functional piece to reciprocate along an output axis, wherein the output axis extends along the front-back direction of the electric tool;

the impact mechanism includes:

the impact rod can be abutted with the top end functional piece;

it is characterized in that the method comprises the steps of,

the impact energy density of the electric hammer is greater than or equal to 23000J/min;

8. The power tool of claim 7, wherein:

the impact frequency of the power tool is greater than or equal to 4200BPM.

9. An electric tool configured to perform at least an impact operation through a tip function, the electric tool comprising:

a motor;

a driving mechanism for generating a driving force;

the impact mechanism includes:

the impact rod can be abutted with the top end functional piece;

it is characterized in that the method comprises the steps of,

the impact energy density of the electric hammer is greater than or equal to 23000J/min; the impact frequency of the power tool is greater than or equal to 4200BPM.

10. The power tool of claim 9, wherein:

the impact frequency of the electric tool is greater than or equal to 4350 BPM.