CN107627263B - Electric hammer - Google Patents

Abstract

The application provides an electric hammer, the whole machine weight of the electric hammer is between 0.9Kg and 1.6Kg, which comprises: the device comprises a motor, an intermediate shaft, a swing rod bearing and a cylinder assembly; the motor is in transmission connection with the intermediate shaft; the cylinder assembly includes: a cylinder, a striker accommodated in the cylinder, and a striker rod engaged with the striker; the swing rod bearing is sleeved on the intermediate shaft, and a swing rod of the swing rod bearing is connected with the air cylinder; the ratio of the distance from the center line of the cylinder to the center line of the intermediate shaft to the inner diameter of the cylinder is 1.20 to 1.75. The electric hammer provided by the application has small volume under the condition of ensuring the working efficiency to be basically unchanged.

Description

Electric hammer

Technical Field

The application relates to an electric hammer, and belongs to the technical field of electric tools.

Background

Various power tools are often used in engineering construction, such as drilling holes in concrete, floor slabs, brick walls, and stone using electric hammers.

The existing electric hammer with the weight of the whole machine between 0.9Kg and 1.6Kg mainly comprises a motor, a transmission mechanism, an impact mechanism, a chuck and other components, wherein the weight of the whole machine refers to the weight of the electric hammer after a battery pack, an auxiliary handle and a working head are removed. Specifically, the transmission mechanism includes: the motor is in transmission connection with the intermediate shaft, the swing rod bearing and the intermediate gear are sleeved on the intermediate shaft, and the swing rod bearing and the intermediate gear can rotate together with the intermediate shaft. The impact mechanism includes: the device comprises a cylinder connected with a swing rod sleeved on a swing rod bearing, a ram accommodated in the cylinder and a ram matched with the ram. The chuck is fixed at the front end of the impact mechanism to clamp different types of working heads, so that the purpose of drilling under different working conditions is achieved.

However, the existing electric hammer has a large volume, and is uncomfortable for an operator to hold, so that the electric hammer is inconvenient to operate.

Disclosure of Invention

The present application provides an electric hammer to solve the above-mentioned or other potential technical problems existing in the prior art.

According to some embodiments of the present application, there is provided an electric hammer having a total weight of between 0.9Kg and 1.6Kg, including: the device comprises a motor, an intermediate shaft, a swing rod bearing and a cylinder assembly; the motor is in transmission connection with the intermediate shaft; the cylinder assembly includes: a cylinder, a striker accommodated in the cylinder, and a striker rod engaged with the striker; the swing rod bearing is sleeved on the intermediate shaft, and a swing rod of the swing rod bearing is connected with the ram; the ratio of the distance from the center line of the cylinder to the center line of the intermediate shaft to the inner diameter of the cylinder is 1.20 to 1.75.

The electric hammer as described above, wherein the distance from the center line of the cylinder to the center line of the intermediate shaft is 23.5mm to 25.5mm.

The electric hammer as described above, wherein the distance from the center line of the cylinder to the center line of the intermediate shaft is 24.5mm.

The electric hammer further comprises an input gear and a chuck assembly, wherein the input gear is sleeved on the intermediate shaft and is in transmission connection with the motor; the chuck assembly is arranged in front of the striker; the ratio of the distance of the input gear to the collet assembly to the inner diameter of the cylinder is from 6.32 to 7.11.

The electric hammer as described above, wherein the input gear is 120mm to 135mm from the collet assembly.

The electric hammer as described above, wherein the striker includes: the end face of the first part is matched with the ram, the end face of the second part is matched with the working head, and the area of the cross section of the second part is larger than that of the cross section of the first part.

The electric hammer as described above, wherein a ratio of a length of the striker rod to an inner diameter of the cylinder is 0.667 to 0.865.

The electric hammer as described above, wherein the length of the striking rod is 13mm to 16mm.

The electric hammer as described above, wherein the outer diameter of the motor is not more than 46mm.

The electric hammer as described above, wherein the stack length of the motor is not more than 15mm, wherein the stack length of the motor refers to the overlap length of the rotor and the stator in the motor.

The electric hammer as described above, wherein the cylinder has an inner diameter of 18.5mm to 19.5mm.

The electric hammer as described above, wherein the cylinder has an inner diameter of 19mm.

The electric hammer as described above, wherein the weight of the hammer is 36 g to 46 g.

The electric hammer as described above, wherein the weight of the hammer is 42 g.

The electric hammer as described above, wherein the frequency at which the hammer strikes the striker is 5400 to 6000 times/min.

The electric hammer, wherein the whole machine weight of the electric hammer is 1.4Kg.

According to the technical scheme of the embodiment of the application, when the ratio of the distance from the center line of the air cylinder to the center line of the intermediate shaft to the inner diameter of the air cylinder is 1.20-1.75, the electric hammer is small in size, the working efficiency is basically unchanged, an operator can grasp the electric hammer more conveniently, and the operation is more flexible.

Additional aspects of the application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the application.

Drawings

The above and other objects, features and advantages of embodiments of the present application will become more readily apparent from the following detailed description with reference to the accompanying drawings. Embodiments of the application will now be described, by way of example and not limitation, in the figures of the accompanying drawings, in which:

fig. 1 is a schematic structural diagram of an electric hammer according to an embodiment of the present application;

fig. 2 is a schematic view of the striker in fig. 1.

In the figure:

11. a motor; 121. An intermediate shaft;

122. an input gear; 123. A swing rod bearing;

124. an output gear; 131. A cylinder;

132. a ram; 133. A striker;

1331. a rear end face; 1332. A front end face;

1333. a boss; 1334. Sealing grooves;

141. a rotating sleeve; 142. A transmission gear;

143. a locking block; 15. A housing;

16. a handle; 171. A sliding sleeve;

172. a dust cover; 173. A gasket;

174. a pressing plate; 175. A spring;

d, the distance from the central line of the cylinder to the central line of the intermediate shaft;

l is the distance from the input gear to the chuck assembly;

and d, the inner diameter of the cylinder.

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present application and should not be construed as limiting the application.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

Example 1

Fig. 1 is a schematic structural view of an electric hammer according to the present embodiment, and fig. 2 is a schematic structural view of a striker in fig. 1. It should be noted that the electric hammer of the present embodiment is applicable to electric hammers with a total weight of 0.9Kg to 1.6Kg, preferably 1.2Kg to 1.6Kg, and further, 1.4Kg. The weight of the whole machine is the weight of the electric hammer after the battery pack, the auxiliary handle and the working head are removed.

As shown in fig. 1, the electric hammer of the present embodiment includes a casing 15, a motor 11, a transmission mechanism, a cylinder assembly, and a rotary sleeve 141. The front end (right end in fig. 1) of the casing 15 is a working end when the electric hammer is operated, the rear end (left end in fig. 1) of the casing 15 is a holding end for holding the electric hammer by a user, and a handle 16 is provided at the rear end of the casing 15. A swivel 141 is mounted in the housing 15, and the handle 16 is disposed obliquely with respect to the axis of the swivel 141.

The rotary sleeve 141 houses a cylinder assembly therein to provide power for the hammering operation of the working head. The cylinder assembly includes: a cylinder 131 housed in the rotary sleeve 141 and capable of reciprocating, a hammer 132 housed in the cylinder 131, and a plunger 133 having both ends respectively engaged with the hammer 132 and the working head. Referring to fig. 2, optionally, a sealing groove 1334 is formed on the ram 132, and a sealing ring is installed in the sealing groove 1334 to improve the tightness between the ram 132 and the rotating sleeve 141. Similarly, the plunger 133 may be provided with a sealing groove 1334, and a sealing ring may be installed in the sealing groove 1334 to improve the sealing property between the plunger 133 and the rotating sleeve 141. It will be appreciated that when the ram 132 and the striker 133 are both provided with the seal groove 1334, a sealing effect can be provided, thereby preventing leakage of grease.

The front part of the rotating sleeve 141 is provided with a long groove which radially penetrates through the outer wall of the rotating sleeve 141 and is closed in the direction parallel to the axis of the rotating sleeve 141, the groove wall of the long groove is provided with an inclined surface, and a locking block 143 which is approximately spherical is arranged in the long groove. When the locking block 143 is clamped into the long groove, the locking block 143 can only partially extend into the rotating sleeve 141 under the restriction of the inclined plane to be matched with the groove formed on the working head, so that the locking block 143 cannot fall into the rotating sleeve 141. A chuck assembly for holding the working head is further sleeved on the front part of the rotating sleeve 141, that is, the chuck assembly is arranged in front of the ram 133. The chuck assembly includes: a sliding sleeve 171 sleeved on the periphery of the rotating sleeve 141, and a dust cover 172 mounted on the front end of the sliding sleeve 171. A washer 173 matched with the locking block 143 is fixed in the sliding sleeve 171 and used for limiting the locking block 143 to prevent the locking block 143 from falling out of the long groove. A pressing plate 174 engaged with the locking block 143 is fixed to the rear portion of the washer 173, and a spring 175 is provided between the pressing plate 174 and the swivel 141. The swivel 141 includes: the front part, the rear part and the step surface connecting the front part and the rear part, and the diameter of the front part is smaller than that of the rear part, one end of the spring 175 is propped against the step surface, and the other end is propped against the rear surface of the pressing plate 174.

A transmission gear 142 in transmission connection with the transmission mechanism is also fixed on the rotating sleeve 141, so that the rotating sleeve 141 is driven to rotate by the transmission mechanism. In this embodiment, the transmission mechanism includes: an input gear 122, a swing rod bearing 123, an intermediate shaft 121, and an output gear 124. An input gear 122 of the transmission mechanism is fixed to the intermediate shaft 121 and meshes with a gear of an output shaft of the motor 11 to drive the intermediate shaft 121 of the transmission mechanism to rotate by the motor 11. The output gear 124 of the transmission mechanism is mounted on the intermediate shaft 121 and meshes with a transmission gear 142 fixed to the rotary sleeve 141 to rotate the rotary sleeve 141.

With continued reference to FIG. 1, the swing rod bearing 123 of the transmission includes an inner race and an outer race. Wherein the inner ring is sleeved on the second shaft part of the intermediate shaft 121 and can rotate around the central shaft; the swing rod integrally formed with the outer ring is hinged with the cylinder 131 of the cylinder assembly, so that when the intermediate shaft 121 drives the inner ring to rotate, the swing rod can swing along the axis of the intermediate shaft 121, so that the cylinder 131 reciprocates along the axis of the rotary sleeve 141, air between the inner wall of the cylinder 131 and the ram 132 is compressed, the ram 132 is pushed to strike the ram 133, and the working head is driven to reciprocate along the axis of the rotary sleeve 141, so that the chiseling operation is performed.

It is contemplated that when the drive gear 142 on the swivel 141 and the ram 132 in the cylinder assembly are driven simultaneously through the intermediate shaft 121, the drilling and chiseling operations may be performed simultaneously if the working head is clamped within the collet assembly.

However, the existing electric hammers are too large in size and are not beneficial to operators. In order to reduce the volume of the electric hammer, some single members of the electric hammer have been tried to be miniaturized by those skilled in the art. For example, some embodiments employ a method in which the motor 11 is adjusted to be inclined from the longitudinal direction of the hammer, but the hammer manufactured by this embodiment has a somewhat reduced length but an increased width. In addition, when such electric hammers are used in environments where the space is relatively small, the operation is still very inconvenient. As another example, another solution employs a manner of decreasing the inner diameter d of the cylinder 131, but this solution causes a significant decrease in the working efficiency of the electric hammer. Therefore, how to reduce the volume of the electric hammer while ensuring the working efficiency of the electric hammer is a problematic problem that has not been solved in the art.

In order to obtain the electric hammer with small size and basically unchanged working efficiency, the applicant has conducted a great deal of tests and experiments on various components (including but not limited to the motor 11, the transmission mechanism, the rotary sleeve 141, the chuck assembly, the cylinder assembly and the like) affecting the electric hammer size and working efficiency and the synergy between them, and finally found that the electric hammer can be made smaller in size and basically unchanged in working efficiency by controlling the ratio between the distance (hereinafter referred to as the center distance D) D between the center line of the cylinder 131 and the center line of the intermediate shaft 121 and the inner diameter D of the cylinder 131, thereby making it easier for the operator to grasp the electric hammer and also facilitating the operation of drilling, chiseling and the like using the electric hammer. Specifically, when the ratio between the center distance D and the cylinder 131D is 1.20 to 1.75, the volume of the electric hammer is reduced by at least 15% with respect to the volume of electric hammers of the same weight level on the market, and it can be ensured that the working efficiency of the electric hammer is not lowered.

Further, in order to make the electric hammer have a smaller width (longitudinal distance in fig. 1) to reduce the volume of the whole machine, the center distance D may be selected to be any value from 23.5mm to 31.5mm, for example, the center distance D may be 23.5mm, 24.5mm, 25.5mm, or 31.5mm. Through practical tests, when the center distance D is 23.5mm to 25.5mm, the suitability between the volume and the operability of the electric hammer is relatively good, and preferably, when the center distance D is 24.5mm, the electric hammer is small in volume, and is easy to operate by an operator in a handheld manner, and meanwhile, the movable space of each part in the electric hammer can be ensured.

It should be understood that, in the present embodiment, when the center distance D takes any value of 23.5mm to 31.5mm, the inner diameter D of the cylinder 131 is only required to be able to satisfy the ratio of the center distance D to 1.20 to 1.75, and the value of the inner diameter D of the cylinder 131 is not limited in the present embodiment.

Specifically, each center distance D may correspond to the same cylinder 131 inner diameter value, for example, 17mm, 19mm, or 20mm. Of course, each center distance D may correspond to a different value of the inner diameter D of the cylinder 131 at the time of design. For example, in some alternative embodiments, the center distance D is 31.5mm, the inner diameter D of the cylinder 131 is 18mm, i.e. the ratio of the two is 1.75, and the electric hammer is smaller than the electric hammer with the same weight level on the market, so that the electric hammer is more convenient for a user to operate. In other alternative embodiments, the center distance D is preferably 24.5mm, and the inner diameter D of the cylinder 131 is 19mm, that is, the ratio of the two is 1.29, so that the volume of the electric hammer can be further reduced, the operation convenience of the electric hammer can be further improved, and the suitability between the volume and the operability of the electric hammer can be further improved. In other embodiments, the center distance D is 23.5mm, the inner diameter D of the cylinder 131 is 19.5mm, i.e., the ratio of the two is 1.20, and the volume of the electric hammer is further reduced.

The electric hammer of this embodiment can reduce the volume of the electric hammer by controlling the ratio between the center distance D and the inner diameter D of the cylinder 131, so that the electric hammer is smaller and more compact, the electric hammer is convenient for an operator to use the electric hammer to perform operations such as drilling, chiseling and the like on the surface of a workpiece, and the working efficiency of the electric hammer is ensured to be basically unchanged.

Example two

The present embodiment is to improve the distance L from the hammer input gear 122 to the chuck assembly (hereinafter referred to as "case length") on the basis of embodiment 1, so as to further reduce the volume of the hammer.

Specifically, in the present embodiment, the ratio of the length L of the case to the inner diameter d of the cylinder 131 is set to 6.32 to 7.11 to reduce the length of the hammer, thereby achieving the purpose of reducing the volume of the hammer. Alternatively, the length L of the case may be set to 120mm to 135mm to make the overall structure of the hammer more compact on the basis of being able to mount the internal structure of the lower hammer, thereby reducing the volume of the hammer. For example, the length L of the case is 120mm, the inner diameter D of the cylinder 131 is 19mm, and the center distance D may be 24.5mm. For another example, the length L of the case is 123.7mm, the inner diameter D of the cylinder 131 is 19mm, and the center distance D may be 24.1mm. For another example, the tank length L is 135mm, the inner diameter D of the cylinder 131 is 19mm, and the center distance D may be 25.35mm.

Alternatively, as shown in fig. 2, in order for the distance L from the input gear 122 to the collet assembly to satisfy the above-described value, the cross-sectional area of the end face of the second portion of the striker 133 that mates with the working head may be set larger than the cross-sectional area of the end face of the first portion of the striker 133 that mates with the hammer 132, that is, the inner diameter of the front end face 1332 of the striker 133 that mates with the working head is larger than the inner diameter of the rear end face 1331 of the striker 133 that mates with the hammer 132. Specifically, the rear end of the ram 133 matched with the ram 132 is formed with a boss 1333, and the front end of the ram 133 matched with the working head is not formed with the boss 1333, so that the front end of the ram 133 cannot extend into the front portion of the smaller inner diameter of the rotary sleeve 141 as in the conventional ram 132, and accordingly, in order to adapt to the shortened ram 133, the distance between the rotary sleeve 141 and the chuck assembly of the electric hammer in the embodiment is reduced, so that the rear end of the working head can be contacted when the ram 133 works, so as to transfer hammering energy to the surface of the working piece.

Alternatively, the ratio of the length of the striker 133 to the inner diameter d of the cylinder 131 may be 0.667 to 0.865, thereby minimizing energy loss between the striker 132 and the striker 133, improving the working efficiency of the striker 132 and reducing the volume of the electric hammer.

In practical design, the length of the striker rod may be 13mm to 16mm, preferably 15.5mm. For example, the length of the striker 133 may be 13mm, the inner diameter D of the cylinder 131 19.5mm, and at this time, the length L of the case may be 135mm, and the center distance D may be 25.5mm. For another example, the length of the striker 133 may be 15.5mm, the inner diameter D of the cylinder 131 may be 19mm, and at this time, the length L of the case may be 120mm, and the center distance D may be 24.5mm. For another example, the length of the striker 133 may be 16mm, the inner diameter D of the cylinder 131 may be 18.5mm, and at this time, the length L of the case may be 130mm, and the center distance D may be 24.1mm. In the present embodiment, the length of the striker is preferably 15.5mm, and the inner diameter d of the cylinder 131 is preferably 19mm.

In the electric hammer of the present embodiment, by setting the ratio of the length L of the case to the inner diameter d of the cylinder 131 to 6.32 to 7.11, the length of the electric hammer can be reduced, thereby reducing the volume of the electric hammer. And, when the case length L is 120mm to 135mm, not only can there be provided a sufficient length for arranging the transmission mechanism, the swivel 141, the slide sleeve 171, the cylinder assembly, but also it is possible to make the electric hammer compact in structure and reduce the energy loss of the hammer 132 and the striker 133.

Example III

In this embodiment, on the basis of any one of the above embodiments, the width of the electric hammer is further reduced, so that the volume of the electric hammer is reduced.

Specifically, in the present embodiment, the outer diameter of the motor 11 is not greater than 46mm, so as to reduce the volume occupied by the motor 11, thereby reducing the volume of the electric hammer. Alternatively, the stacking length of the motor 11 may be set to be not greater than 15mm, so that the volume occupied by the motor 11 may be reduced continuously, and the working capacity of the motor 11 is ensured to be capable of satisfying operations such as drilling, chiseling and the like on the surface of the workpiece. Further, when the outer diameter of the motor 11 is 46mm and the stack length is 15mm, the volume of the hammer can be reduced with respect to a hammer of the same hammer weight on the market. In the present embodiment, the overlap length of the motor 11 refers to the overlap length of the rotor and the stator in the motor 11.

The electric hammer of this embodiment can further reduce the volume of electric hammer under the condition that the work efficiency of electric hammer basically satisfies the requirement to make the electric hammer more small and exquisite.

Example IV

The present embodiment is an improvement on the basis of any of the above embodiments to improve the working efficiency of the electric hammer, that is, the efficiency of the electric hammer for performing operations such as drilling, chiseling, etc. on the surface of the workpiece. Specifically, the working efficiency refers to the inverse ratio of the time required for the electric hammer to make holes of the same diameter and the same depth using the same diameter working head.

Although the above embodiment reduces the volume of the hammer by at least 15% compared to the volume of the hammer of the same weight level on the market, and ensures that the working efficiency of the hammer is substantially unchanged or reduced only slightly. The applicant conducted a great deal of tests and experiments on components affecting the working efficiency of the electric hammer (including but not limited to the motor 11, the rotor 141, the cylinder assembly, etc.) and their coordination again, and as a result, found that when the inner diameter d of the cylinder 131 is set to 18.5mm to 19.5mm, the working efficiency of the electric hammer can be improved while reducing the volume of the electric hammer.

Specifically, the working power of the working head clamped in the electric hammer chuck assembly is derived from the hammering kinetic energy of the ram 133 on the working head in the cylinder assembly and the rotation torque of the working head driven by the rotating sleeve 141. In general, in order to improve the working efficiency of the electric hammer, to reduce the time for the electric hammer to punch holes in a workpiece, it is necessary to increase the frequency with which the striker 133 hammers the working head per unit time, or the number of turns of the working head per unit time. When the diameter of the cylinder 131 is 18.5mm to 19.5mm, the single striking energy of the ram 132 striking the ram 133 can be increased, and the working efficiency of the ram 132 can be improved on the basis of reducing the volume of the ram 132 by matching the corresponding center distance D. After practical tests, it is found that, compared with the hammer 132 with the same weight level in the market, the electric hammer of the embodiment can reduce the volume by at least 15%, and the working efficiency can be improved by at least 20%.

In a specific design, the inner diameter D of the cylinder 131 may be arbitrarily matched with the center distance D as long as the ratio of the first embodiment is satisfied. For example, when the inner diameter D of the cylinder 131 is 18.5mm, the center distance D may be selected to be 31.5mm. For another example, when the inner diameter D of the cylinder 131 is 19mm, the center distance D may be selected to be 24.5mm, and the above value is also a preferable value for the present embodiment. The electric hammer under the value has the advantages of small volume, high working efficiency and better matching property of the electric hammer and the working efficiency. For another example, when the inner diameter D of the cylinder 131 is 19.5mm, the center distance D may be selected to be 23.5mm.

Further, the weight of the hammer 132 may be set to 34g to 42g to continue to increase the single striking energy when the hammer 132 strikes the striker 133, thereby improving the working efficiency of the electric hammer. For example, when the weight of the ram 132 is 34g, the diameter of the cylinder 131 may be selected to be 18.5mm. For another example, when the weight of the hammer 132 is 38g, the diameter of the cylinder 131 may be selected to be 19mm. Preferably, when the weight of the ram 132 is 42g, the diameter of the cylinder 131 may be selected to be 19.5mm.

Through testing, in a specific test prototype, the electric hammer had a total weight of 1.4Kg, a center distance D of 24.5mm, a case length L of 123.7mm, a striker 133 length of 15.5mm, an outer diameter of the motor 11 of 15mm, a weight of the ram 132 of 38g, and an inner diameter D of the cylinder 131 of 19mm. When the electric hammer is used for punching holes with the depth of 50mm and the apertures of 6mm, 8mm and 10mm, only 5.3s, 6.8s and 9.5s are needed respectively, and the time needed for punching holes with the same depth and the same aperture by the electric hammer with the same weight level on the market is shortened by at least 1.8s, 2.3s and 0.7s respectively. From the above test data, it can be seen that the working efficiency of the electric hammer of this embodiment is significantly improved compared with that of the existing electric hammer.

The electric hammer of this embodiment can further improve the work efficiency of the electric hammer by controlling the inner diameter d of the cylinder 131 on the premise of ensuring that the electric hammer body is compact.

Example five

The embodiment is improved on the basis of the first embodiment, the second embodiment or the third embodiment so as to improve the working efficiency of the electric hammer. Specifically, the frequency at which the striker 132 strikes the striker 133 is set to 5400 to 6000 times/min. By controlling the striking frequency of the hammer 132, good working efficiency can be obtained.

Specifically, in the actual design, the frequency of the impact hammer 132 on the impact bar 133 can be adjusted by selecting and matching the motor 11, the swing rod bearing, the number of teeth of the gear, the modulus and the like, so that the purpose of improving the working efficiency of the electric hammer is achieved.

Example six

On the basis of any embodiment, optionally, the electric hammer can work normally at high temperature by selecting high-temperature resistant grease and adopting a high-temperature resistant material to manufacture the transmission mechanism. Still alternatively, a bracket shaped like a Chinese character '8' is used to support and position the intermediate shaft 121 and the cylinder 131 to enhance the positioning strength of the cylinder 131 and the intermediate shaft 121 to enhance the stability of the cylinder 131, see patent publication No. CN206066361U, which is incorporated herein by reference in its entirety. Still alternatively, a seal ring is provided between the motor 11 bracket and the housing 15 and a pressure relief hole is provided between the output gear 124 and the transmission gear 142 to improve the sealability of the grease, see the patent of the application of publication No. CN204913815U, which is incorporated by reference in its entirety.

In the description of the present application, a description of the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims (16)

1. An electric hammer having a total weight of between 0.9Kg and 1.6Kg, the total weight being the weight of the electric hammer excluding a battery pack, an auxiliary handle and a working head, the electric hammer comprising: the device comprises a shell, a motor, an intermediate shaft, a swing rod bearing and a cylinder assembly;

a handle is arranged at the rear end of the shell;

the motor is in transmission connection with the intermediate shaft;

the cylinder assembly includes: a cylinder, a striker accommodated in the cylinder, and a striker rod engaged with the striker;

the swing rod bearing is sleeved on the intermediate shaft, and a swing rod of the swing rod bearing is connected with the air cylinder;

characterized in that the ratio of the distance from the center line of the cylinder to the center line of the intermediate shaft to the inner diameter of the cylinder is 1.20 to 1.75.

2. The electric hammer of claim 1, wherein the distance from the centerline of the cylinder to the centerline of the intermediate shaft is 23.5mm to 25.5mm.

3. The electric hammer of claim 1, wherein the distance from the centerline of the cylinder to the centerline of the intermediate shaft is 24.5mm.

4. The electric hammer of claim 1, further comprising an input gear and a collet assembly, the input gear being sleeved on the intermediate shaft and in driving connection with the motor; the chuck assembly is arranged in front of the striker; the ratio of the distance of the input gear to the collet assembly to the inner diameter of the cylinder is from 6.32 to 7.11.

5. The electric hammer of claim 4, wherein the input gear is 120mm to 135mm from the collet assembly.

6. The electric hammer of claim 5, wherein the striker bar includes: the end face of the first part is matched with the ram, the end face of the second part is matched with the working head, and the area of the cross section of the second part is larger than that of the cross section of the first part.

7. The electric hammer of claim 5, wherein a ratio of a length of the striker rod to an inner diameter of the cylinder is 0.667 to 0.865.

8. The electric hammer of claim 5, wherein the striker rod has a length of 13mm to 16mm.

9. The electric hammer of claim 1, wherein the motor has an outer diameter of no greater than 46mm.

10. The electric hammer of claim 9, wherein the stack length of the motor is no greater than 15mm, wherein the stack length of the motor refers to the overlap length of the rotor and stator in the motor.

11. The electric hammer of any one of claims 1-10, wherein the cylinder has an inside diameter of 18.5mm to 19.5mm.

12. The electric hammer of claim 11, wherein the cylinder has an inner diameter of 19mm.

13. The electric hammer of claim 12, wherein the weight of the ram is 36 grams to 46 grams.

14. The electric hammer of claim 13 wherein the weight of the ram is 42 grams.

15. The electric hammer of any one of claims 1-10 wherein the ram strikes the ram at a frequency of 5400 to 6000 times/min.

16. The electric hammer according to any one of claims 1-10, characterized in that the electric hammer has a total weight of 1.4Kg.