An electric impact wrench

Abstract

The utility model relates to an electric impact wrench belongs to electric tool technical field, the wrench includes the host computer of being equipped with tool head and the control handle connected with host computer, the host computer contains the cover of the motor drive arrangement, the lower part of cover extends the support protruding, the support protruding forms the radial support and axial location structure of pin shaft, to install with the pin shaft of tool head axial parallel, pin shaft end portion sets up elastic member, the handle upper part has the containing space of adapting with support protruding, the containing space end portion has the elastic member axial location and the circumferential containment structure, makes the handle connect with host computer through pin shaft and elastic member, the utility model discloses elastic member containing space increases significantly, can design the size of elastic member as needed, makes it have the ideal energy absorption damping effect.

Description

Technical Field

[0001] This utility model relates to a wrench, and more particularly to an electric impact wrench, belonging to the field of power tool technology. Background Technology

[0002] A typical structure for an impact wrench can be found in patent document application number 201410250660.5. Because the main body housing and handle of the wrench are integrally injection-molded, they are high-rigidity, continuous structures. The vibration energy generated during wrench operation can be transmitted to the handle and battery pack through this structure. Vibration causes fatigue for the operator and reduces the reliability of the wrench's electrical connections. With the increasing operating torque of wrenches, the urgency of solving these problems is becoming increasingly apparent.

[0003] A search reveals that Chinese patent document application number 201821011173.3 discloses an impact wrench, including a handle, a housing, and a battery pack extension foot. The handle has one end and another end, with the other end used to install the battery pack. The housing is connected to one end of the handle and is used to house a motor and / or transmission components. A first fastener securely connects the handle to the housing. An elastic element is also provided between the handle and the housing, and the elastic element is sleeved on the first fastener. During operation, the elastic element can reduce the vibration transmitted from the housing to the handle, reducing vibration impact and thus providing a vibration damping effect. This protects the impact wrench, reduces the failure rate, and increases its service life.

[0004] However, the above-mentioned existing technology has the following shortcomings: 1) Its elastic element extends in a direction perpendicular to the output shaft. Since the space available to accommodate the elastic element in this direction is limited, the size of the elastic element is limited. The ability of the elastic element to absorb impact energy is strongly positively correlated with its thickness in the impact vibration direction, resulting in limited vibration reduction effect; 2) The working environment of high temperature and cyclic alternating stress will lead to accelerated aging of the elastic element made of soft rubber sleeve, thus causing the buffering function to fail; 3) The buffering performance is not adjustable. Utility Model Content

[0005] The purpose of this utility model is to address the main shortcomings of the existing technology by improving the structure and proposing an electric impact wrench with a significantly increased elastic element accommodating space, thereby improving the vibration reduction effect.

[0006] To achieve the above objectives, the basic technical solution of the electric impact wrench of this utility model is: including a main unit equipped with a tool head and a control handle connected to the main unit; The main unit includes a housing for housing a motor drive device. A support protrusion extends from the lower part of the housing. The support protrusion forms a radial support and axial limiting structure for a pin, which is used to install a pin parallel to the axis of the tool head. An elastic element is fitted at the end of the pin. The upper part of the handle has a receiving space adapted to the support protrusion, and the end of the receiving space has an axial limiting and circumferential containment structure of the elastic element, so that the handle is connected to the main unit through the pin and the elastic element.

[0007] This invention breaks through the traditional structure where the extension direction of the elastic element is perpendicular to the axis of the tool head, allowing it to extend in a direction parallel to the tool head. As a result, the space for the elastic element is significantly increased, and the size of the elastic element can be designed as needed to achieve an ideal energy absorption and vibration reduction effect.

[0008] Further: The main unit consists of a cup-shaped gearbox housing at the front end and right and left covers that fit together at the rear. The lower part of the gearbox housing extends out a front support protrusion with a reduced-diameter stepped support hole at one end. The lower parts of the right and left covers extend out protrusions with semi-circular notches on their mating surfaces. After mating, they form a rear support protrusion with reduced-diameter stepped support holes at both ends.

[0009] Further: The front support protrusion is inserted into the pin with the reduced diameter end, and the rear support protrusion formed by the two protrusions hugs the other pin with reduced diameter at both ends, forming a radial support and axial limiting structure for the front and rear pins.

[0010] Furthermore: the handle is formed by joining left and right half shells, and the upper part of the left and right half shells extends forward and backward support wings respectively towards the tool head axis. Several left and right partitions in the joined left and right half shells form front and rear receiving spaces that are adapted to the front and rear support protrusions respectively; the center lines of the two pins are coaxial and parallel to the axis of the tool head.

[0011] Furthermore, the two ends of the pin are respectively fitted with rubber damping sleeves as elastic elements, and the inner end of each rubber damping sleeve has an extension edge.

[0012] Furthermore, the mating surfaces of the left and right ribs each have recesses that are adapted to the extended edges of the rubber damping sleeves. When mated, they hold the corresponding extended edges, forming an axially limiting and circumferentially enclosing structure, allowing the handle to be connected to the main unit through pins at two locations and the rubber damping sleeves.

[0013] Furthermore, the front and rear support wings on the upper part of the left and right half shells are respectively provided with inverted T-shaped slots perpendicular to the axis of the tool head. When they are aligned, the lower part of the I-shaped cross-section rubber vibration damping pad that is adapted to it is inserted. The upper surface of the rubber vibration damping pad is in close contact with the small plane of the corresponding part of the lower surface of the host. Attached Figure Description

[0014] The present invention will be further described below with reference to the accompanying drawings.

[0015] Figure 1 This is a schematic diagram of the external structure of Embodiment 1 of this utility model.

[0016] Figure 2 yes Figure 1 A partial cross-sectional view of the embodiment.

[0017] Figure 3 yes Figure 2 A schematic diagram of the three-dimensional exploded structure.

[0018] Figure 4 yes Figure 1 A three-dimensional structural diagram of the head section of the embodiment.

[0019] Figure 5 yes Figure 2 A magnified structural diagram at point E in the middle.

[0020] Figure 6 yes Figure 1 A cross-sectional view of the assembly of the head and handle in the embodiment. Detailed Implementation Example 1

[0021] The basic structure of the electric impact wrench in this embodiment is as follows: Figure 1 As shown, it includes a main unit 100 with a tool head and a control handle 200 connected to the main unit, with a battery pack 300 inserted at the bottom of the handle 200.

[0022] For detailed structure, please refer to Figures 2 to 6 The main unit 100 consists of a cup-shaped gearbox housing 4 at the front and right and left covers 3 and 2 at the rear, forming an outer shell. A motor, gearbox, and impact transmission mechanism are installed within this shell, similar to existing technologies and will not be detailed further. The lower part of the cast aluminum gearbox housing 4 extends a front support protrusion 4-1 with a reduced-diameter stepped support hole at one end. The lower parts of the injection-molded right and left covers 3-1 and 2-1, respectively, extend protrusions 3-1 and 2-1 with semi-circular notches on their mating surfaces. When mated, these form a rear support protrusion with reduced-diameter stepped support holes at both ends. The front support protrusion inserts into a pin 7 with a reduced-diameter end, and the mated rear support protrusion holds another pin 7 with reduced diameters at both ends, thus forming radial support and axial limiting structures for the front and rear pins 7, respectively. The combination of the integrated front support protrusion and the mating rear support protrusion ensures reliable support and facilitates manufacturing and assembly.

[0023] The center lines of the two pins 7 are coaxial and parallel to the axis of the tool head. Rubber damping sleeves 8, which act as elastic elements, are fitted onto both ends of the pins 7. The inner end of each damping sleeve 8 has an extension flange 8-1 (see...). Figure 5This forms a T-shaped cross-section with perforations.

[0024] The handle 200 is formed by the mating of left and right half-shells 5 and 6. The upper parts of both half-shells 5 and 6 extend axially toward the tool head, respectively, with front support wings 5-1 and 6-1 and rear support wings 5-2 and 6-2. After mating, several left and right ribs within the left and right half-shells 5 and 6 form front and rear receiving spaces that respectively match the front and rear support protrusions. The mating surfaces of the left and right ribs each have recesses that match the extension edges 8-1 of the rubber damping sleeves 8. Therefore, during mating, these recesses hold the corresponding extension edges 8-1 of the rubber damping sleeves 8, forming an axially limiting and circumferentially enclosing structure. Ultimately, the handle 200 is connected to the main unit 100 via two pins 7 and the rubber damping sleeves 8, thus providing both circumferential and axial cushioning and damping effects. To ensure the vibration reduction effect in the impact direction of this embodiment, the front support wings 5-1 and 6-1 and the rear support wings 5-2 and 6-2 on the upper part of the left and right half-shells 5 and 6 are respectively provided with inverted T-shaped slots perpendicular to the axis of the tool head. When aligned, the lower part of the I-shaped cross-section rubber vibration damping pad 9 is inserted to form a reliable positioning constraint for the latter. The upper surface of the rubber vibration damping pad 9 is in close contact with the small plane of the corresponding part of the lower surface of the main unit 100 (with pre-compression during assembly), which helps to further enhance the buffering and vibration reduction effect.

[0025] Compared with existing technologies, this embodiment, by changing the traditional design concept of the elastic element extending perpendicular to the tool head axis, makes reasonable use of the axial space of the tool head, and therefore has the following significant advantages: the buffer and vibration damping structure arranged parallel to the output shaft has a wider spatial dimension, providing a larger buffer space for absorbing impact vibration energy, and achieving good buffering effect even when a larger impact torque is required for operation. Tests show that the circumferential impact acceleration is reduced by approximately 15%.

[0026] In addition to the embodiments described above, this utility model may have other implementations. All technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by this utility model.

Claims

1. An electric impact wrench, comprising a main unit equipped with a tool head and a control handle connected to the main unit; characterized in that: The main unit includes a housing for housing a motor drive device. A support protrusion extends from the lower part of the housing. The support protrusion forms a radial support and axial limiting structure for a pin, which is used to install a pin parallel to the axis of the tool head. An elastic element is fitted at the end of the pin. The upper part of the handle has a receiving space adapted to the support protrusion, and the end of the receiving space has an axial limiting and circumferential containment structure of the elastic element, so that the handle is connected to the main unit through the pin and the elastic element.

2. The electric impact wrench according to claim 1, characterized in that: The main unit consists of a cup-shaped gearbox housing at the front end and right and left covers that fit together at the rear. The lower part of the gearbox housing extends out a front support protrusion with a reduced-diameter stepped support hole at one end. The lower parts of the right and left covers extend out protrusions with semi-circular notches on their mating surfaces. When mated, they form a rear support protrusion with reduced-diameter stepped support holes at both ends.

3. The electric impact wrench according to claim 2, characterized in that: The front support protrusion is inserted into a pin with a reduced diameter end, and the rear support protrusion formed by the two protrusions hugs another pin with reduced diameter at both ends, forming a radial support and axial limiting structure for the front and rear pins.

4. The electric impact wrench according to claim 3, characterized in that: The handle is formed by joining left and right half shells. The upper part of each half shell extends forward and backward support wings towards the tool head axis, respectively. Several left and right ribs inside the joined left and right half shells form front and rear receiving spaces that are adapted to the front and rear support protrusions, respectively. The center lines of the two pins are coaxial and parallel to the axis of the tool head.

5. The electric impact wrench according to claim 4, characterized in that: Both ends of the pin are fitted with rubber damping sleeves as elastic elements, and the inner end of each rubber damping sleeve has an extension edge.

6. The electric impact wrench according to claim 5, characterized in that: The mating surfaces of the left and right ribs each have recesses that fit the extended edges of the rubber damping sleeves. When mated, they hold the corresponding extended edges, forming an axially limiting and circumferentially enclosing structure, allowing the handle to be connected to the main unit via pins at two locations and the rubber damping sleeves.

7. The electric impact wrench according to claim 6, characterized in that: The front and rear support wings on the upper part of the left and right half shells are respectively provided with inverted T-shaped slots perpendicular to the axis of the tool head. When they are aligned, the lower part of the I-shaped cross-section rubber vibration damping pad is inserted to fit the slot. The upper surface of the rubber vibration damping pad is in close contact with the small plane of the corresponding part of the lower surface of the main unit.

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