CN211729048U - Electric hammer - Google Patents

Abstract

The utility model provides an electric hammer, which comprises a casing; a motor accommodated in the housing; a battery pack for supplying electric energy for the rotation of the motor; the output mechanism is used for connecting the chuck component and comprises a rotating sleeve and a collision rod accommodated in the rotating sleeve, and the collision rod can linearly move relative to the rotating sleeve; the transmission mechanism is connected with the motor and the output mechanism and comprises an intermediate shaft, a swing rod bearing and a cylinder assembly, the motor and the intermediate shaft are in transmission connection through a gear, the swing rod bearing is arranged on the intermediate shaft, and the swing rod bearing can rotate along with the intermediate shaft; the rotating sleeve is in transmission connection with the intermediate shaft through a gear; the cylinder assembly comprises a cylinder and a hammer at least partially accommodated in the cylinder, the cylinder is accommodated in the rotating sleeve and is connected with the oscillating bar; the cylinder has an inner diameter of 16 to 20 mm and the ram has a mass of 46 to 50 g. Through adopting above-mentioned technical scheme, the quality of adjustment hammer in the electric hammer improves the efficiency of punching of electric hammer, makes the speed of punching very fast.

Description

Electric hammer

Technical Field

The utility model relates to an electric tool field, concretely relates to electric hammer.

Background

Various electric tools are often used in engineering construction, for example, electric hammers are used for drilling holes in concrete, floor slabs, brick walls and stone.

The electric hammer comprises a motor, a transmission mechanism, an impact mechanism and a chuck. Wherein, drive mechanism includes: the swing rod bearing and the intermediate gear can rotate together with the intermediate shaft and can slide along the axis of the intermediate shaft. The impact mechanism includes: a cylinder assembly received within the swivel housing, the cylinder assembly comprising: the cylinder and the striker matched with the hammer, and a swing rod of the swing rod bearing are hinged with the cylinder. The front end of the impact mechanism is fixed with a chuck to clamp different types of working heads, thereby realizing different drilling purposes.

However, the existing electric hammer with the weight of 0.9Kg to 1.6Kg of bare metal after the battery pack, the auxiliary handle and the working head are removed has low drilling efficiency and poor cruising ability.

SUMMERY OF THE UTILITY MODEL

Based on the prior art, the utility model provides an electric hammer aims at promoting the efficiency of punching to keep small and exquisite characteristics.

An electric hammer, comprising:

a housing;

a motor accommodated in the housing for outputting rotational power;

a battery pack for supplying electric energy for the rotation of the motor;

the output mechanism is used for connecting the chuck component and comprises a rotating sleeve and a striker accommodated in the rotating sleeve, and the striker can make linear motion relative to the rotating sleeve so as to hammer a working head clamped on the chuck component;

the transmission mechanism is connected with the motor and the output mechanism and comprises an intermediate shaft, a swing rod bearing and a cylinder assembly, the motor and the intermediate shaft are in transmission connection through a gear, the swing rod bearing is mounted on the intermediate shaft, and the swing rod bearing can rotate along with the intermediate shaft; the rotating sleeve is in transmission connection with the intermediate shaft through a gear; the cylinder assembly comprises a cylinder and a hammer at least partially accommodated in the cylinder, the hammer is used for impacting the striker, the cylinder is accommodated in the rotating sleeve, and the cylinder is connected with a swing rod of the swing rod bearing;

the cylinder has an inner diameter of 16 mm to 20 mm, and the ram has a mass of 46 g to 50 g.

Preferably, the ram has a mass of 47.5 grams.

Preferably, the working head can be mounted on the rotating sleeve through a chuck assembly, and the output rotating speed of the working head mounted on the electric hammer is 1200-1400 rpm.

Preferably, the working head can be mounted on the rotating sleeve through a chuck assembly, and the output rotating speed of the working head mounted on the electric hammer is 1300 rpm.

Preferably, the motor is a brushless motor.

Preferably, the rotation speed of the intermediate shaft is 4100 to 4800 revolutions per minute.

Preferably, the motor is disposed obliquely with respect to the intermediate shaft.

Preferably, the bare metal mass of the electric hammer is 0.9Kg to 1.6 Kg.

Preferably, the bare metal mass of the electric hammer is 1.2Kg to 1.6 Kg.

Preferably, the bare metal mass of the electric hammer is 1.4 Kg.

By adopting the technical scheme, the punching efficiency of the electric hammer is improved by adjusting the quality of the ram in the electric hammer, so that the punching speed is higher.

In addition, the application of the brushless motor on the electric hammer enables the bare engine to be relatively lighter in weight while the electric hammer is small and small, and simultaneously reduces the energy loss of the electric hammer for drilling a single hole; the efficiency of punching is improved, the energy loss of punching a single hole is reduced, and the cruising ability of the electric hammer is enhanced; that is, under the condition that the voltage and the capacity of the battery pack are the same, the single battery pack can enable the electric hammer in the technical scheme to punch more holes.

Drawings

Fig. 1 shows a schematic structural view of an electric hammer according to an embodiment of the present invention.

Description of the reference numerals

1 case

2 electric machine

3-transmission mechanism 31, first gear 32, intermediate shaft 33, second gear 34, swing rod bearing 35, third gear 36 and fourth gear

4 cylinder assembly 41 cylinder 42 ram

5 rotating sleeve

6 handle

7 Battery pack

F front and back direction

Detailed Description

In order to more clearly illustrate the above objects, features and advantages of the present invention, the detailed description of the embodiments of the present invention is provided in this section in conjunction with the accompanying drawings. The present invention can be embodied in other different forms than the embodiments described in this section, and those skilled in the art can make various modifications, changes and substitutions without departing from the spirit of the present invention, so that the present invention is not limited to the specific embodiments disclosed in this section. The protection scope of the present invention shall be subject to the claims.

The electric hammer of the embodiment is suitable for the electric hammer with the bare metal mass between 0.9Kg and 1.6Kg, preferably, the bare metal mass of the electric hammer is between 1.2Kg and 1.6Kg, and more preferably, the bare metal mass of the electric hammer is 1.4 Kg. Wherein, the bare machine mass refers to the mass of the electric hammer after removing the battery pack, the auxiliary handle, the working head or similar accessories. The electric hammer is suitable for processing holes with diameters of 6mm to 10 mm.

As shown in fig. 1, the electric hammer includes a casing 1, a motor 2, a transmission mechanism 3, an output mechanism and a battery pack 7, wherein the motor 2, the transmission mechanism 3 and the output mechanism are all installed in the casing 1. The battery pack 7 provides electric energy for the rotation of the motor 2, and the transmission mechanism 3 is connected with the motor 2 and the output mechanism, so that the rotation power output by the motor 2 is transmitted to the output mechanism through the transmission mechanism 3. In fig. 1, the upper and lower portions of the axis O of the output mechanism are shown as two states of the cylinder assembly 4. The front end (right end in fig. 1) of the casing 1 is a working end when the electric hammer works, the rear end (left end in fig. 1) of the casing 1 is a holding end for a user to hold the electric hammer, and a handle 6 is arranged at the rear end of the casing 1. The handle 6 is disposed obliquely with respect to the front-rear direction F of the electric hammer.

The output mechanism comprises a rotating sleeve 5 and a striking rod, the striking rod is accommodated in the rotating sleeve 5, and the front part of the striking rod is provided with a chuck component for clamping the working head. The striker rod can make linear motion relative to the rotating sleeve 5, so as to hammer the working head clamped on the chuck component.

The transmission mechanism 3 includes a first gear 31, an intermediate shaft 32, a second gear 33, a swing rod bearing 34, a third gear 35, a fourth gear 36, and the cylinder assembly 4. The first gear 31 is connected to an output shaft of the motor 2, the intermediate shaft 32 is rotatably mounted in the housing, the second gear 33 and the third gear 35 are mounted on the intermediate shaft 32, and the second gear 33 is meshed with the first gear 31 to enable the motor 2 to drive the intermediate shaft 32 to rotate. The axis of the motor 2 is inclined with respect to the forward and backward direction F of the electric hammer, the axis of the intermediate shaft 32 coincides with the forward and backward direction F of the electric hammer, and the first gear 31 and the second gear 33 are bevel gears. The fourth gear 36 is attached to the sleeve 5, the axial direction of the sleeve 5 coincides with the front-rear direction F of the hammer, and the third gear 35 and the fourth gear 36 mesh with each other to rotationally drive the sleeve 5. Thus, when the corresponding working head is clamped on the chuck component, a user can drill holes by using the electric hammer provided by the embodiment.

The cylinder assembly 4 includes a cylinder 41 and a hammer 42, the hammer 42 is at least partially accommodated in the cylinder 41, the hammer 42 is disposed at the rear end of the ram and can reciprocate along the axial direction of the cylinder 41, so that the hammer 42 strikes the ram to provide power for the hammering operation of the working head. The swivel sleeve 5 has a cavity, and the cylinder 41 is accommodated in the cavity of the swivel sleeve 5.

The inner diameter of the cylinder 41 is 16 mm to 20 mm. It can be understood that in the field of electric hammers, the range of the internal diameter of the cylinder 41 directly affects the weight and the working capacity of the hammer, for example, for light electric hammers with a bare weight of between 1.2Kg and 1.6Kg, the internal diameter of the cylinder 41 can be 19 mm.

The swing rod bearing 34 is mounted on the intermediate shaft 32, and the swing rod bearing 34 includes an inner ring, an outer ring and a swing rod. Wherein the inner race is mounted to the intermediate shaft 32 and is rotatable with the intermediate shaft 32. The swing rod integrally formed with the outer ring is hinged to the cylinder 41, so that when the intermediate shaft 32 drives the inner ring to rotate, the swing rod can swing back and forth along the axis of the intermediate shaft 121, so that the cylinder 41 reciprocates along the axis of the rotary sleeve 5, air between the inner wall of the cylinder 41 and the ram 42 is compressed, the ram 42 is pushed to impact the ram, and the working head is driven to reciprocate along the axis of the rotary sleeve 5 to perform chisel operation.

It is conceivable that, when the fourth gear 36 and the hammer 42 on the rotary sleeve 5 are simultaneously driven, if the working head is held in the chuck assembly, the drilling and the boring operations can be simultaneously performed.

The intermediate shaft 32 has a rotational speed of 4100 to 4800 rpm, for example 4500 rpm. The rotational speed of the intermediate shaft 32 corresponds to the swing frequency of the swing lever, which corresponds to the impact frequency of the hammer 42. The reasonable hammer rotation ratio setting of the hammer 42 represents the high efficiency of the electric hammer, and the working efficiency of the hammer 42 is high when the hammer rotation ratio is set to 47:9 in this embodiment. Under the condition that the rotating speed range of the intermediate shaft 32 is determined, the transmission ratio of the gear between the motor and the intermediate shaft can be adjusted according to the selected motor 2 and the rotating speed thereof, so that the high efficiency of the electric hammer is ensured.

Further, a seal groove is formed in the outer peripheral surface of the hammer 42, and a seal ring is mounted in the seal groove to improve the sealing property between the hammer 42 and the sleeve 5. Similarly, the peripheral surface of the plunger may also be provided with a sealing groove, and a sealing ring is mounted in the sealing groove to improve the sealing property between the plunger and the rotating sleeve 5. It can be understood that when the sealing grooves are formed on both the ram 42 and the ram rod, a sealing function can be achieved.

Through research and experiments, the applicant finds that the aim of improving the working efficiency of the electric hammer can be fulfilled by adjusting the mass of the hammer 42. The punch was made using 5 electric hammer prototypes with rams 42g, 45g, 47.5g, 49.8g and 52g, respectively, and the time taken for the prototypes to punch holes of the same diameter and depth in the same material was recorded. The diameter of the hammer 42 is matched with the inner diameter of the cylinder 41 in the case where the inner diameter of the cylinder 41 is determined, and the mass of the hammer is changed by changing the length of the hammer 42 in the test in the case where the material of the hammer 42 is not changed, so that the diameter of the hammer 42 and other parameters are the same in 5 tests.

TABLE 1

As can be seen from table 1, when the mass of the hammer is 42g to 49.8g, the working efficiency of the electric hammer is improved and the time taken for punching is reduced when the mass of the hammer 42 is increased. In the above test, when the mass of the hammer 42 was 47.5g, the time taken to punch holes of sizes 6 × 50 and 8 × 50 was the shortest, and when the mass of the hammer 42 was 49.8g, the time taken to punch holes of sizes 10 × 80 was the shortest. However, when the weight of the hammer 42 is 49.8g or 52g, the hammer vibrates significantly during punching, and the hand feeling of holding is reduced. When the mass of the ram 42 continues to increase to 54.3 grams, the hammer fails to operate properly and the hole cannot be punched. Thus, a ram having a mass of 46 to 50 grams is selected for this embodiment. Preferably, the ram has a mass of 47.5 grams.

The applicant has also found that by adjusting the output speed of the working head, the working efficiency of the electric hammer can be improved. Punching holes by using an electric hammer prototype with the working head respectively having the output rotating speeds of 800 rpm, 900 rpm, 1000 rpm, 1100 rpm, 1200 rpm, 1300 rpm and 1400 rpm, and recording the time taken for the electric hammer prototype to punch holes with the same hole diameter and the same depth on the same material. The transmission ratio of the gear is not adjusted in 7 tests, the output rotating speed of the working head is changed by changing the voltage applied to the motor, so the hammer rotating ratio (the ratio of the impact times of the hammer to the rotating number of the rotating sleeve in unit time) of the electric hammer is not influenced, and other parameters except the rotating speed are the same in 7 tests.

TABLE 2

As can be seen from Table 2, when the output rotation speed of the working head is 800 to 1300 rpm, the higher the output rotation speed of the working head is, the shorter the time required for punching is. In addition, the applicant also finds that when the output rotation speed of the working head exceeds 1300 rpm, the rotation speed of the motor is correspondingly increased, so that the movement amplitude of the air cylinder is too large, the energy of the swing rod bearing 34 cannot be completely converted into the hammering energy of the hammer 42, the punching efficiency is reduced, and the punching time is prolonged. Therefore, in this embodiment, the output rotation speed of the working head is set to 1200 to 1300 rpm. Preferably, the output rotation speed of the electric hammer working head is set to 1300 rpm. With a predetermined range of rotation speeds of the intermediate shaft 32 (4100 rpm to 4800 rpm), a desired output rotation speed of the hammer head can be achieved by adjusting the gear ratios of the third gear 35 and the fourth gear 36.

It will be understood that, in the present document, it is not limited to controlling the mass of the ram 42 and the output speed of the working head at the same time, and in some embodiments, the mass of the ram 42 or the output speed of the working head may be controlled separately.

Holes with the same aperture and the same depth are punched on the same material by using an electric hammer sample machine provided with a brush motor and a brushless motor respectively, the batteries of the electric hammer sample machine are all lithium battery packs with the same voltage of 20V and the same capacity of 2.0Ah, and the punching number of the electric hammer using the brush motor and the brushless motor is recorded respectively.

TABLE 3

Aperture x depth (mm x mm)	6×50	8×50	10×80
				Motor with brush (one)	34	40	21
Brushless motor (single)	55	56	26

As can be seen from table 3, when the voltage of the battery pack is the same and the capacity is the same, the number of holes that can be punched by the hammer using the brushless motor is larger. The use of a brushless motor allows the energy loss of the electric hammer for drilling a single hole to be reduced. Due to the fact that the punching efficiency is improved and the energy loss of punching a single hole is reduced, the cruising ability of the electric hammer can be improved, and a plurality of holes can be punched after a single battery pack is fully charged. And the electric hammer uses the brushless motor to make the electric hammer keep the volume less while the bare engine is light.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention.

Claims (10)

1. An electric hammer, characterized in that it comprises:

a housing (1);

a motor (2) accommodated in the housing (1) for outputting rotational power;

a battery pack (7) for providing electric energy for the rotation of the motor (2);

the output mechanism is used for connecting the chuck component and comprises a rotating sleeve (5) and a striker accommodated in the rotating sleeve (5), and the striker can make linear motion relative to the rotating sleeve (5) so as to hammer a working head clamped on the chuck component;

the transmission mechanism (3) is connected with the motor (2) and the output mechanism, the transmission mechanism (3) comprises an intermediate shaft (32), a swing rod bearing (34) and a cylinder assembly (4), the motor (2) is in gear transmission connection with the intermediate shaft (32), the swing rod bearing (34) is mounted on the intermediate shaft (32), and the swing rod bearing (34) can rotate along with the intermediate shaft (32); the rotating sleeve (5) is in transmission connection with the intermediate shaft (32) through a gear; the cylinder assembly (4) comprises a cylinder (41) and a hammer (42) at least partially accommodated in the cylinder (41), the hammer (42) is used for impacting the striker, the cylinder (41) is accommodated in the rotating sleeve (5), and the cylinder (41) is connected with a swing rod of the swing rod bearing (34);

the cylinder (41) has an inner diameter of 16 mm to 20 mm, and the ram (42) has a mass of 46 g to 50 g.

2. An electric hammer according to claim 1, wherein the ram (42) has a mass of 47.5 grams.

3. An electric hammer according to claim 1, wherein the working head can be mounted to the rotary sleeve (5) by means of a collet assembly, and the output speed of the working head mounted on the electric hammer is 1200-1400 rpm.

4. An electric hammer according to claim 1, wherein the working head is mountable to the rotary sleeve (5) by means of a collet assembly, and the output speed of the working head mounted on the electric hammer is 1300 rpm.

5. An electric hammer according to claim 1, wherein the motor (2) is a brushless motor.

6. An electric hammer according to claim 1, wherein the rotation speed of the intermediate shaft (32) is 4100 to 4800 revolutions per minute.

7. An electric hammer according to claim 1, wherein the motor (2) is disposed obliquely with respect to the intermediate shaft (32).

8. The electric hammer according to any one of claims 1 to 7, wherein the bare metal mass of the electric hammer is 0.9Kg to 1.6 Kg.

9. The electric hammer according to any one of claims 1 to 7, wherein the bare metal mass of the electric hammer is 1.2Kg to 1.6 Kg.

10. The electric hammer according to any one of claims 1 to 7, wherein the bare metal mass of the electric hammer is 1.4 Kg.

Images