Electric hammer

Abstract

According to the technical scheme, the electric hammer comprises a shell; the motor is arranged in the shell and is used for providing driving force; the chuck assembly is used for clamping a working head; the transmission assembly is configured to receive the driving force of the motor and act on the working head; the transmission assembly comprises an air cylinder, a piston, a rammer, a sinker bar and a rotating sleeve, the air cylinder is a hollow cylindrical component and is rotationally supported in the shell, the rotating sleeve is a hollow cylindrical component and is at least partially arranged in the air cylinder, the piston, the rammer, the sinker bar and the rotating sleeve are sequentially arranged in the air cylinder in the rotating axis direction of the air cylinder, and the piston receives driving force of the motor and drives the motor to rotate. The sinker bar reciprocates back and forth in the cylinder and is at least partially arranged in the rotating sleeve; the transmission assembly further comprises a partition part, the partition part and the rotating sleeve form a first cavity, and the partition part and the rammer form a second cavity. The electric hammer can reduce the vibration of the whole electric hammer and improve the use comfort of an operator.

Description

Technical Field

[0001] This application relates to the field of tool technology, and in particular to electric hammers. Background Technology

[0002] With the increasing development of power tools, impact power tools used for chiseling or drilling on surfaces of hard materials such as walls and concrete are becoming increasingly popular among consumers.

[0003] In related technologies, electric hammers have a rotating mechanism and an impact mechanism. The rotating mechanism can provide rotational force to the working head, and the impact mechanism can provide impact force to the working head. In the impact mechanism, the cylinder and the rotating sleeve can rotate synchronously with relative axial movement. The piston in the cylinder is driven by the motor to move back and forth, which drives the hammer in the cylinder to move back and forth. The hammer strikes the striking rod in the rotating sleeve, and the striking rod transmits the impact force to the working head to drill and impact the working surface.

[0004] However, in the existing technology, when the electric hammer is working, the rotating sleeve that moves back and forth due to impact will generate a large vibration, which will make the operator feel uncomfortable and cause numbness in the hand. Utility Model Content

[0005] Therefore, it is necessary to provide a hammer drill to address the vibration problem of hammer drills.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows:

[0007] In one embodiment, an electric hammer is provided, comprising: a housing; a motor disposed within the housing for providing driving force; a chuck assembly for holding a working head; and a transmission assembly configured to receive the driving force of the motor and act on the working head. The transmission assembly includes a cylinder, a piston, a hammer, a striker, and a rotating sleeve. The cylinder is a hollow cylindrical component and is rotatably supported within the housing. The rotating sleeve is a hollow cylindrical component and is at least partially disposed within the cylinder. The piston, hammer, striker, and rotating sleeve are sequentially disposed within the cylinder along the rotation axis of the cylinder. The piston receives the driving force of the motor and reciprocates back and forth within the cylinder. The striker is at least partially disposed within the rotating sleeve.

[0008] Furthermore, the transmission assembly also includes a partition, the partition and the rotating sleeve forming a first chamber, and the partition and the hammer forming a second chamber.

[0009] Furthermore, the partition is either fixedly connected to or separately installed from the impact bar.

[0010] Furthermore, the partition is also equipped with a flow passage that connects the first chamber and the second chamber.

[0011] Furthermore, the projected area of ​​the flow passage along the rotation axis of the cylinder accounts for 0.01 to 0.05 of the projected area of ​​the cylinder bore.

[0012] Furthermore, the flow passage is configured as a through hole, and the size of the opening of the flow passage on the side of the partition facing the hammer is greater than or equal to the size of the opening of the flow passage on the side of the partition facing the rotating sleeve.

[0013] Furthermore, the flow passage is configured as a notch that is radially recessed inward on the outer peripheral wall of the partition, and the width of the notch decreases radially inward along the partition.

[0014] Furthermore, the flow passage is located within the radial range of the partition and the cylinder, and the flow passage is annular.

[0015] Furthermore, multiple flow passages are configured, and these multiple flow passages are evenly arranged circumferentially along the rotation axis of the cylinder.

[0016] Furthermore, the partition section facing the hammer is configured as a curved surface that bulges outward from the center.

[0017] Furthermore, the cylinder's peripheral wall is provided with a through hole, one side of which connects to the outside of the cylinder, and the other side connects to the first chamber.

[0018] In this embodiment, by separating the chamber between the rotating sleeve and the hammer, the compressed gas generated by the hammer during impact is prevented from acting directly on the rotating sleeve, thereby reducing the vibration caused by the movement of the rotating sleeve and improving the operator's comfort. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of an electric hammer according to one embodiment of this application;

[0020] Figure 2 This is a partial cross-sectional view of an electric hammer in one embodiment of this application;

[0021] Figure 3 This is a partially enlarged view of the electric hammer in one embodiment of this application;

[0022] Figure 4 This is a schematic diagram of the partition portion according to the first embodiment of this application;

[0023] Figure 5 This is a schematic diagram of the flow passage in the second embodiment of this application;

[0024] Figure 6 This is a schematic diagram of the flow passage in the third embodiment of this application;

[0025] Figure 7 This is a partially enlarged view of the electric hammer in one embodiment of this application;

[0026] Figure Descriptions: 1. Outer shell; 11. Transmission housing; 12. Motor housing; 2. Handle assembly; 3. Chuck assembly; 31. Working head; 311. First groove; 32. Spring; 4. Auxiliary handle; 5. Motor; 6. Transmission housing; 61. Cylinder; 61a. First chamber; 61b. Second chamber; 611. Second through hole; 612. Vent hole; 62. Piston; 63. Hammer; 64. Impact rod; 641. Third groove; 65. Rotating sleeve; 651. Hollow part; 652. First through hole; 653. Second groove; 654. Third through hole; 66. First limiting member; 67. Second limiting member; 68. Third limiting member; 69. Partition part; 691. Flow passage part. Detailed Implementation

[0027] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0028] In the description of this 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., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0030] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0031] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0032] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0033] See Figure 1 Figure 1 shows a perspective view of an electric hammer according to an embodiment of this application, including a housing 1, a handle assembly 2, a chuck assembly 3, and an auxiliary handle 4. The handle assembly 2 is disposed at the rear end of the housing 1, the chuck assembly 3 is disposed at the front end of the housing 1 away from the handle assembly 2, and the auxiliary handle 4 is detachably connected to the housing 1 and disposed between the handle assembly 2 and the chuck assembly 3.

[0034] The outer casing 1 includes a transmission housing 11 and a motor housing 12, which are fixedly connected.

[0035] See Figure 2 , Figure 2A partial cross-sectional view of an electric hammer according to an embodiment of this application is shown, including a motor 5 (not shown in the figure) and a transmission assembly 6. The motor 5 is housed in a motor housing 12 and is used to output driving force. The transmission assembly 6 is disposed in a transmission housing 11 and receives the driving force of the motor 5 for driving the working head 31 held in the chuck assembly 3 to move. The working head 31 can be selectively rotated along its own axis and / or reciprocated back and forth along its own axis.

[0036] The transmission assembly 6 includes a cylinder 61, a piston 62, a hammer 63, a striking rod 64, and a rotating sleeve 65. The cylinder 61 is a hollow cylindrical component and is rotatably supported in the transmission housing 11; the rotating sleeve 65 is a hollow cylindrical component that can reciprocate back and forth along the rotation axis of the cylinder 61 and rotates integrally with the cylinder 61 around the rotation axis. The rotating sleeve 65 is at least partially housed in the cylinder 61 and at least partially exposed from the cylinder 61; the hammer 64 is always disposed within the cylinder 61; the piston 62, hammer 63, striking rod 64, and rotating sleeve 65 are sequentially disposed within the cylinder 61 along the rotation axis of the cylinder 61. The piston 62 receives the driving force of the motor 5 and reciprocates back and forth within the cylinder 61, driving the movement of the hammer 63 and the striking rod 64; the striking rod 64 is at least partially housed within the rotating sleeve 65 and at least partially exposed within the rotating sleeve 65 and housed within the cylinder 61.

[0037] The chuck assembly 3 is sleeved on the rotating sleeve 65, and a spring 32 is also provided at the rear end of the chuck assembly 3. The spring 32 is axially clamped between the chuck assembly 3 and the cylinder 61. When the chuck assembly 3 is subjected to an axial driving force toward the cylinder 61, the spring 32 is compressed and moves closer to the cylinder 61.

[0038] The working head 31 is inserted into the hollow portion 651 of the rotating sleeve 65 and rotates integrally with the rotating sleeve 65, while its axial movement range is limited. Specifically, the rotating sleeve 65 is also equipped with a first limiting member 66, a first through hole 652 is provided on the peripheral wall of the rotating sleeve 65, and an axially extending first groove 311 is provided on the outer periphery of the working head 31. The first limiting member 66 is at least partially accommodated in the first through hole 652 and is axially limited on the rotating sleeve 65. The first limiting member 66 is at least partially accommodated in the first groove 311 and can move movably within the first groove 311.

[0039] The rotating sleeve 65 is housed in the hollow portion 611 of the cylinder 61 and rotates integrally with the cylinder 61, while axially restricting its range of movement. Specifically, the cylinder 61 is also provided with a second limiting member 67, a second through hole 611 is provided on the peripheral wall of the cylinder 61, and an axially extending second groove 653 is provided on the outer periphery of the rotating sleeve 65. The second limiting member 67 is at least partially accommodated in the second through hole 611 and axially restricted on the cylinder 61, and at least partially accommodated in the second groove 653 and movable within the second groove 653.

[0040] The striking rod 64 is housed in the hollow portion 651 of the rotating sleeve 65 and rotates integrally with the rotating sleeve 65, while axially restricting its range of movement. Specifically, the rotating sleeve 65 is also provided with a third limiting member 68, a third through hole 654 is provided on the peripheral wall of the rotating sleeve 65, and an axially extending third groove 641 is provided on the outer periphery of the striking rod 64. The third limiting member 68 is at least partially housed in the third through hole 654 and axially restricted on the rotating sleeve 65. The third limiting member 68 is at least partially housed in the third groove 641 and is movable within the third groove 641.

[0041] A sealing assembly is also provided between the cylinder 61 and the rotating sleeve 65, and another sealing assembly is provided between the rotating sleeve 65 and the impact rod 65. The two sets of sealing assemblies restrict the leakage of grease and gas, so that the transmission assembly 6 has a long service life.

[0042] During operation, the operator grips the handle assembly 2 and applies a thrust in the impact direction to the working head 31. The working head 31 abuts against the working surface and moves towards the cylinder 61 against the elastic force of the spring 32. The first limiting member 66 moves to the left side of the first groove 311, and the second limiting member 67 moves in the second groove 653 following the compression of the spring 311. Therefore, when the rotating sleeve 65 is subjected to a large impact on the side near the hammer 63, the rotating sleeve 65 has a tendency to move towards the chuck assembly 3.

[0043] See Figure 3 , Figure 3 A partially enlarged view of an electric hammer according to one embodiment of this application is shown. In some embodiments of this application, the transmission assembly 6 further includes a partition 69, which is disposed in the cylinder 61 and located between the rotating sleeve 65 and the hammer 63. The partition 69 and the rotating sleeve 65 form a first chamber 61a, and the partition 69 and the hammer 63 form a second chamber 61b. By dividing the cavity between the rotating sleeve 65 and the hammer 63 into two chambers through the partition 69, the axial pressure directly applied to the rotating sleeve 65 by the hammer 63 during its rapid reciprocating motion can be effectively avoided, thereby reducing the vibration of the electric hammer and alleviating operator fatigue.

[0044] In some embodiments of this application, the partition 69 and the impact rod 64 are fixedly disposed. The partition 69 is disposed on the end side of the impact rod 64 near the impact hammer 63. The partition 69 and the impact rod 64 can be integrally formed or detachable separate components. Specifically, the integrally formed partition 69 and the impact rod 64 can be made of metal, which improves the service life of the material; the detachable separate partition 69 and the impact rod 64 can be fastened by threaded connection, snap-fit, or interference fit, etc. The impact rod 64 can be made of metal, and the partition 69 can be made of metal or plastic.

[0045] In some embodiments of this application, the partition 69 and the impact rod 64 may be separate components. The partition 69 and the impact rod 64 slide relative to each other along the rotation axis of the cylinder 61. Optionally, the partition 69 is disposed between the impact rod 64 and the hammer 63. The partition 69 may be made of metal to improve its strength. Alternatively, the partition 69 may be sleeved on the impact rod 64 and slide on the impact rod 64 under the axial pressure of the hammer 63. The partition 69 may be made of metal to improve its service life, or it may be made of plastic to reduce the overall weight of the machine and improve user comfort.

[0046] In some embodiments of this application, the partition 69 is further provided with a flow passage 691, which connects the first chamber 61a and the second chamber 61b. It is understood that when the partition 69 is subjected to axial pressure and moves towards the rotating sleeve 65, the gas in the first chamber 61a can flow through the flow passage 691 into the second chamber 61b to alleviate the gas pressure in the first chamber 61a, thereby reducing the axial pressure exerted on the rotating sleeve 65 by the gas pressure, and thus reducing the vibration of the entire machine. A ventilation hole 612 is also provided on the peripheral wall of the cylinder 61, which connects the internal space of the cylinder 61 and the external space of the cylinder 61. When the hammer 63 is driven by the piston 62 to move towards the partition 69, if the partition 69 is on the side of the ventilation hole 612 closer to the rotating sleeve, the second chamber... The gas in chamber 61b flows from the vent 612 to the external space of cylinder 61 to reduce the gas pressure in the second chamber 61b, avoid energy loss caused by excessive gas pressure, and improve the efficiency of energy transfer between hammer 63 and impact rod 64. If the partition 69 is located on the side of vent 612 closer to hammer 63, the gas in the second chamber 61b reaches the first chamber 61a through the flow passage 691, and can further reach the external space of cylinder 61 through the vent 612, thereby reducing the gas pressure in the second chamber 61b, avoiding energy loss caused by excessive gas pressure, and improving the efficiency of energy transfer between hammer 63 and impact rod 64.

[0047] In some embodiments of this application, the projected area of ​​the flow passage 691 along the rotation axis of the cylinder 61 is 0.01 to 0.05 of the projected area of ​​the inner bore of the cylinder 61. A ratio less than or equal to 0.05 can prevent gas in the second chamber 61b from rapidly entering the first chamber 61a, thus avoiding excessive axial pressure on the rotating sleeve 65 and reducing overall vibration. A ratio greater than or equal to 0.01 can guide the discharge of gas when it is necessary to exhaust gas from the first chamber 61a, and can also discharge gas from the second chamber 61b through the flow passage 691 when the hammer 63 impacts the rotating sleeve 65, reducing energy loss due to compressed gas and increasing the impact force of the hammer 63 on the impact rod 64.

[0048] See Figure 4 , Figure 4 A schematic diagram of the partition portion according to the first embodiment of this application is shown. In some embodiments of this application, the flow passage 691 is configured as a through hole, and the opening size of the flow passage 691 on the side of the partition portion 69 facing the hammer 63 is greater than or equal to the opening size of the flow passage 691 on the side of the partition portion 69 facing the rotating sleeve 65. At this time, when the hammer 63 moves rapidly toward the rotating sleeve 65, the gas in the second chamber 61b can quickly flow into the first chamber 61a, reducing the energy loss caused by compressed gas and increasing the impact force of the hammer 63 on the impact rod 64. Optionally, the smaller opening diameter of the flow passage 691 is between 2mm and 4mm. Optionally, there are multiple flow passages 691, which are axially and evenly arranged on the partition portion 69 around the rotation axis of the cylinder 61.

[0049] See Figure 5 , Figure 5 A schematic diagram of the partition portion according to a second embodiment of this application is shown. In some embodiments of this application, the flow passage 691 is configured as a notch with a radially inward recess on the outer peripheral wall of the partition portion 69, and the width of the notch decreases radially inward along the partition portion 69. Optionally, the notch is "V" shaped, so that it can be formed in one step by a mold, avoiding secondary processing. Optionally, there are multiple flow passages 691, and they are axially evenly arranged on the partition portion 69 about the rotation axis of the cylinder 61.

[0050] See Figure 6 , Figure 6 A schematic diagram of the partition portion according to a third embodiment of this application is shown. In some embodiments of this application, the flow passage 691 is disposed within the radial range between the outer diameter of the partition portion 69 and the inner bore of the cylinder 61, and the flow passage 691 is annular. In this case, the flow passage 691 is disposed on the periphery of the partition portion 69, and the gas flow between the first chamber 61a and the second chamber 61b is uniform and stable.

[0051] In some embodiments of this application, the partition portion 69 is configured with a curved surface bulging outward from the center on the side facing the hammer 63. When the hammer 63 impacts the partition portion 69, the impact force can be dispersed, the impact fatigue of the partition portion 69 can be alleviated, and the service life of the partition portion 69 can be increased.

[0052] See Figure 7 , Figure 7A partially enlarged view of an electric hammer according to one embodiment of this application is shown. In some embodiments of this application, the peripheral wall of the cylinder 61 is provided with a ventilation hole 613. One side of the ventilation hole 613 connects to the external space of the cylinder 61, and the other side connects to the first chamber 61a. Optionally, multiple ventilation holes 613 are provided and are evenly distributed circumferentially along the rotation axis of the cylinder 61. This arrangement of the ventilation holes 613 can quickly discharge the compressed gas in the first chamber 61a, thereby reducing the axial pressure on the rotating sleeve 65 and improving the operator's comfort.

[0053] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0054] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An electric hammer, comprising: shell; A motor, configured within the housing, is used to provide driving force; Chuck assembly for holding the working head; The transmission assembly is configured to receive the driving force of the motor and act on the working head; The transmission assembly includes a cylinder, a piston, a hammer, a striking rod, and a rotating sleeve. The cylinder is a hollow cylindrical component and is rotatably supported within the outer casing. The rotating sleeve is a hollow cylindrical component and is at least partially disposed within the cylinder. The piston, hammer, striking rod, and rotating sleeve are sequentially disposed within the cylinder along the rotation axis of the cylinder. The piston receives the driving force of the motor and reciprocates back and forth within the cylinder. The striking rod is at least partially disposed within the rotating sleeve. The transmission assembly is characterized in that it further includes a partition, the partition and the rotating sleeve forming a first chamber, and the partition and the hammer forming a second chamber.

2. The electric hammer as described in claim 1, characterized in that, The partition is either fixedly connected to or separately from the impact rod.

3. The electric hammer as described in claim 1, characterized in that, The partition is also provided with a flow passage, which connects the first chamber and the second chamber.

4. The electric hammer as described in claim 3, characterized in that, The projected area of ​​the flow passage along the rotation axis of the cylinder is 0.01 to 0.05 of the projected area of ​​the cylinder bore.

5. The electric hammer as described in claim 3, characterized in that, The flow passage is configured as a through hole, and the size of the opening of the flow passage on the side of the partition facing the hammer is greater than or equal to the size of the opening of the flow passage on the side of the partition facing the rotating sleeve.

6. The electric hammer as described in claim 3, characterized in that, The flow passage is configured as a notch that is radially recessed inward on the outer peripheral wall of the partition, and the width of the notch decreases radially inward along the partition.

7. The electric hammer as described in claim 3, characterized in that, The flow passage is disposed within the radial range of the partition and the cylinder, and the flow passage is annular.

8. The electric hammer as described in claim 3, characterized in that, The flow passage is provided in multiple parts, and the multiple flow passages are evenly arranged circumferentially along the rotation axis of the cylinder.

9. The electric hammer as described in claim 1, characterized in that, The partition portion is configured with a curved surface that bulges outward from the center on the side facing the hammer.

10. The electric hammer as described in claim 1, characterized in that, The cylinder has a through hole on its peripheral wall, one side of which connects to the outside of the cylinder and the other side connects to the first chamber.

Images