Gear box for electric tool and electric tool

Abstract

The utility model discloses a gearbox used for an electric tool and the electric tool, the gearbox used for the electric tool comprises a front end part, a rear end part and a fixing bolt used for connecting the front end part and the rear end part, and a plurality of front fixing parts and rear fixing parts are arranged at the mutually connected positions of the front end part and the rear end part correspondingly; each front fixing part is provided with a first screw hole for a fixing bolt to penetrate through, each rear fixing part is provided with a second screw hole corresponding to the first screw hole, and the fixing bolt is suitable for penetrating through the first screw hole and the second screw hole to be connected with a screw hole in an electric tool shell. Therefore, the gear box can be installed on the shell of the electric tool while the front end part and the rear end part are connected. The gearbox adopts the split design of the front end part and the rear end part, so that the size of an aluminum die-casting die required during processing can be reduced, the processing end surface of the gearbox is reduced, the processing waste is reduced, and the manufacturing cost of the gearbox is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of power tools, and particularly relates to a gearbox for a power tool and a power tool. Background Art

[0002] The gearbox of a power tool is a very important component in the power tool. Its function is to convert the rotational motion of the driving motor into the motion form required by the tool, such as rotational motion or linear motion. The design and manufacturing quality of the gearbox directly affect the performance and service life of the power tool.

[0003] Most of the existing gearboxes of power tools are integral aluminum gearboxes. When processing an integral aluminum gearbox, the size of the aluminum casting mold required is relatively large. During subsequent processing, there are relatively many end faces to be processed, and the waste caused by processing is also relatively large. The overall manufacturing cost of the gearbox is relatively high. In addition, since the entire gearbox is made of aluminum alloy material, the weight of the gearbox is relatively heavy, and the weight of the power tool will be concentrated at the gearbox and the driving motor, and the overall weight is relatively heavy, resulting in a poor holding experience for the user, and the arm is prone to soreness after holding for a period of time. Summary of the Invention

[0004] An object of the present application is to provide a gearbox for a power tool to solve the problem that the size of the aluminum casting mold required during processing of the existing integral aluminum gearbox is relatively large and the manufacturing cost is relatively high.

[0005] Another object of the present application is to provide a power tool.

[0006] To achieve the above object, the technical solution adopted by the present application is as follows: A gearbox for a power tool includes a front end portion, a rear end portion, and fixing bolts for connecting the front end portion and the rear end portion. Multiple front fixing portions and rear fixing portions are respectively provided at the positions where the front end portion and the rear end portion are connected to each other. A first screw hole for the fixing bolt to pass through is provided on each of the front fixing portions, and a second screw hole corresponding to the first screw hole is provided on each of the rear fixing portions. The fixing bolt is adapted to pass through the first screw hole and the second screw hole and then be connected to a screw hole on the housing of the power tool, so as to connect the front end portion and the rear end portion and at the same time mount the gearbox on the housing of the power tool.

[0007] As a preference, a limiting platform is provided on the inner side wall of the connecting end of the front end portion. A first side wall is formed between the limiting platform and the connecting end face of the front end portion. An engaging portion is provided on the connecting end face of the rear end portion, and the engaging portion extends towards the front end portion along the insertion direction. When the front end portion is connected to the rear end portion, the end face of the engaging portion abuts against the limiting platform, and the outer side wall of the engaging portion fits with the first side wall.

[0008] As another preference, connection tongues are provided on the connection end surface of the front end portion, connection slots for the connection tongues to movably plug into are formed on the outer side wall of the connection portion, the connection tongues are of a cantilever structure with one end connected to the front end portion and the other end extending towards the rear end portion along the plugging direction, and the connection slots extend in a direction away from the front end portion along the plugging direction.

[0009] Further preferably, a closed-loop groove is further formed on the outer side wall of the connection portion, a sealing member is arranged in the closed-loop groove, and the sealing member is in interference fit with the closed-loop groove.

[0010] Furthermore, the sealing member is an O-ring washer, and the cross-sectional diameter of the O-ring washer is greater than the depth and width of the closed-loop groove;

[0011] Wherein, the depth of the closed-loop groove refers to the dimension of the closed-loop groove along the radial direction of the connection portion, and the width of the closed-loop groove refers to the dimension of the closed-loop groove along the axial direction of the connection portion.

[0012] Furthermore, a plurality of installation grooves are further formed on the inner side wall of the rear end portion, the installation grooves extend along the plugging direction, the installation grooves are arranged on the inner side wall of the rear end portion at intervals in the circumferential direction, and installation rib strips are formed between adjacent two installation grooves, and the installation rib strips are adapted to be in interference fit with an internal gear ring to realize the connection between the internal gear ring and the rear end portion.

[0013] Furthermore, at least one anti-rotation protrusion is arranged on the outer side wall of the rear end portion, and the anti-rotation protrusion is adapted to cooperate with the housing of the power tool to limit the rotation of the rear end portion relative to the housing of the power tool.

[0014] Furthermore, two anti-rotation protrusions are arranged on the outer side wall of the rear end portion, the two anti-rotation protrusions are symmetrically arranged on the outer side wall of the rear end portion at one end away from the front end portion, and the two anti-rotation protrusions extend along the plugging direction.

[0015] Furthermore, the production material of the front end portion is aluminum alloy, and the production material of the rear end portion is polyhexamethylene adipamide.

[0016] The present application further provides a power tool, which includes a housing and the above-mentioned gearbox, a plurality of third screw holes are formed on the housing, the positions of the third screw holes correspond to the positions of the first screw holes, and the fixing bolts are adapted to pass through the first screw holes and the second screw holes and then be connected to the third screw holes, so that while connecting the front end portion and the rear end portion, the fixing bolts can mount the gearbox on the housing.

[0017] Compared with the prior art, the beneficial effects of the present application are as follows:

[0018] (1) The front end and the rear end of the gearbox adopt a split design. The front end and the rear end can be processed separately, reducing the size of the aluminum die-casting mold required during processing, reducing the end faces to be machined on the gearbox, reducing processing waste, thereby reducing the manufacturing cost of the gearbox, and also being very convenient during gearbox assembly;

[0019] (2) The fixing bolt can pass through the first screw hole and the second screw hole and be connected to the third screw hole on the housing of the power tool, so that while connecting the front end and the rear end together, the fixing bolt can connect the gearbox to the housing of the power tool, simplifying the connection structure on the housing of the power tool and reducing the manufacturing cost;

[0020] (3) The split gearbox enables the front end and the rear end to select different materials. For example, the front end for placing the striker bushing can be selected as aluminum alloy, and the rear end for placing the reduction gear can be selected as polyhexamethylene adipamide, reducing the weight of the gearbox while reducing the manufacturing cost of the gearbox. Description of the Drawings

[0021] Figure 1 It is a schematic structural diagram of the gearbox of this application.

[0022] Figure 2 It is an exploded structural diagram of the gearbox of this application.

[0023] Figure 3 It is a schematic structural diagram of the front end in the gearbox of this application.

[0024] Figure 4 It is a schematic structural diagram of the rear end in the gearbox of this application.

[0025] Figure 5 It is a schematic cross-sectional structural diagram of the gearbox of this application.

[0026] Figure 6 It is a schematic structural diagram of the housing of the power tool of this application.

[0027] Figure 7 It is a partial cross-sectional structural diagram of the power tool of this application.

[0028] In the figure: 100, front end; 110, front fixing part; 111, first screw hole; 120, limiting platform; 130, first side wall; 140, connecting tongue; 200, rear end; 210, rear fixing part; 211, second screw hole; 220, connecting part; 221, closed-loop groove; 222, connecting slot; 230, installation groove; 240, installation rib; 250, anti-rotation protrusion; 300, fixing bolt; 400, housing; 410, third screw hole; 420, anti-rotation groove; 500, seal. Detailed Embodiment

[0029] Next, in combination with specific embodiments, the present application will be further described. It should be noted that, on the premise of non-conflict, the following-described embodiments or technical features can be arbitrarily combined to form new embodiments.

[0030] In the description of the present application, it should be noted that for orientation terms, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation and position relationship are based on the orientation or position relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of the present application.

[0031] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence.

[0032] The terms "comprising" and "having" in the description and claims of the present application and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0033] Referring to Figures 1-5 As shown, the present application provides a gearbox for a power tool, which includes a front end portion 100, a rear end portion 200, and fixing bolts 300 for connecting the front end portion 100 and the rear end portion 200. A striking block bushing is adapted to be provided in the front end portion 100, and a reduction gear assembly is adapted to be provided in the rear end portion 200. A bottom cover is provided at the tail of the rear end portion 200, and a through hole for the output shaft of the driving motor to pass through is opened at the center of the bottom cover, so that the output shaft of the driving motor can pass through the through hole at the center of the bottom cover and be connected to the reduction gear assembly in the rear end portion 200. The power output by the driving motor is decelerated by the reduction gear assembly and then transmitted to the striking block bushing to drive the striking block bushing to move.

[0034] The front end portion 100 and the rear end portion 200 are respectively provided with a plurality of front fixing portions 110 and rear fixing portions 210 at the positions where they are connected to each other. A first screw hole 111 for a fixing bolt 300 to pass through is provided on each front fixing portion 110, and a second screw hole 211 corresponding to the first screw hole 111 in position is provided on each rear fixing portion 210. The fixing bolt 300 is adapted to pass through the first screw hole 111 and the second screw hole 211 and then connect to a third screw hole 410 on the housing of the power tool, so as to install the gearbox on the housing of the power tool while connecting the front end portion 100 and the rear end portion 200, thereby restricting the front end portion 100 and the rear end portion 200 from rotating relative to the housing of the power tool, and the fixing structure inside the housing of the power tool can be simplified by connecting the first screw hole 111, the second screw hole 211 and the third screw hole 410 through the fixing bolt 300.

[0035] Specifically, the front fixing portion 110 is implemented as a front rabbet, and the rear fixing portion 210 is implemented as a rear rabbet. The front end portion 100 includes four front rabbets, and the four front rabbets are symmetrically arranged on the outer side wall of the front end portion 100 near one end of the rear end portion 200. The rear end portion 200 includes four rear rabbets, and the four rear rabbets are symmetrically arranged on the outer side wall of the rear end portion 200 near one end of the front end portion 100. The positions of the front rabbets correspond to the positions of the rear rabbets one by one. A through first screw hole 111 is provided on the front rabbet, and a through second screw hole 211 is provided on the rear rabbet. The fixing bolt 300 can pass through the first screw hole 111 and the second screw hole 211 to connect the front end portion 100 and the rear end portion 200.

[0036] Since the heat generated by the striker bushing arranged in the front end portion 100 is relatively large, the material of the front end portion 100 is preferably aluminum alloy, while the heat generated by the reduction gear assembly arranged in the rear end portion 200 is relatively small, and the material of the rear end portion 200 is preferably polyhexamethylene adipamide. The front end portion 100 and the rear end portion 200 are made of different materials, which can reduce the weight of the gearbox on the premise of ensuring the gear performance, thereby reducing the weight of the power tool and improving the comfort of holding the power tool; in addition, the front end portion 100 and the rear end portion 200 being made of different materials can also reduce the manufacturing cost of the gearbox.

[0037] Furthermore, an engaging portion 220 is provided on the connecting end surface of the rear end portion 200, and the engaging portion 220 extends towards the front end portion 100 along the insertion direction. A limiting platform 120 is provided on the inner side wall of the connecting end of the front end portion 100. A first side wall 130 is formed between the limiting platform 120 and the connecting end surface of the front end portion 100. When the front end portion 100 is connected to the rear end portion 200, the connecting end surface of the front end portion 100 is attached to the connecting end surface of the rear end portion 200. The engaging portion 220 extends into the front end portion 100, the end surface of the engaging portion 220 abuts against the limiting platform 120, and the outer side wall of the engaging portion 220 is attached to the first side wall 130 to improve the stability after the front end portion 100 and the rear end portion 200 are connected.

[0038] A closed-loop groove 221 is provided on the outer sidewall of the connecting portion 220. The closed-loop groove 221 is connected end to end and circumferentially surrounds the outer sidewall of the connecting portion 220. A seal 500 is provided in the closed-loop groove 221. The seal 500 is in interference fit with the closed-loop groove 221. In this way, there is an interference amount between the seal 500 and the closed-loop groove 221, which can effectively seal and prevent the grease in the gearbox from overflowing. The seal 500 can be a rubber gasket. In this way, the seal 500 is installed in a compressed state, and after installation, it can recover its deformation and completely fill the closed-loop groove 221. Preferably, the seal 500 is an O-ring. The cross-sectional diameter of the O-ring is greater than the depth and width of the closed-loop groove 221. Herein, the depth of the closed-loop groove 221 refers to the dimension of the closed-loop groove 221 along the radial direction of the connecting portion 220, and the width of the closed-loop groove 221 refers to the dimension of the closed-loop groove 221 along the axial direction of the connecting portion 220. Thus, there is an interference amount between the O-ring and the closed-loop groove 221, that is, the O-ring can fill the gap between the connecting portion 220 and the front end portion 100, effectively preventing the grease from overflowing.

[0039] In some preferred embodiments, a connecting tongue 140 is further provided on the connecting end surface of the front end portion 100. A connecting slot 222 for the connecting tongue 140 to be movably inserted is formed on the outer sidewall of the connecting portion 220. The connecting slot 222 is located on the side of the closed-loop groove 221 away from the front end portion 100. The connecting tongue 140 is a cantilever structure with one end connected to the front end portion 100 and the other end extending backward along the insertion direction towards the rear end portion 200. The connecting slot 222 extends in the direction away from the front end portion 100 along the insertion direction. When the front end portion 100 is connected to the rear end portion 200, the connecting tongue 140 can be embedded in the connecting slot 222 to further improve the connection strength between the front end portion 100 and the rear end portion 200.

[0040] As Figures 4-5 shown, the side of the rear end portion 200 close to the bottom cover is a reduction gear assembly installation area. A plurality of installation grooves 230 are formed on the reduction gear assembly installation area. The installation grooves 230 extend along the insertion direction. The installation grooves 230 are circumferentially spaced on the inner sidewall of the rear end portion 200. An installation rib 240 is formed between two adjacent installation grooves 230. The installation rib 240 is adapted to be in interference fit with the reduction gear assembly so that the reduction gear assembly can be installed on the rear end portion 200. The arrangement of the installation grooves 230 and the installation ribs 240 enables the reduction gear assembly to only cooperate with the installation ribs 240, which can effectively reduce the contact area between the rear end portion 200 and the reduction gear assembly and prevent the rear end portion 200 from deforming due to excessive temperature.

[0041] In some preferred embodiments, at least one anti-rotation protrusion 250 is further provided on the outer sidewall of the rear end portion 200. The anti-rotation protrusion 250 is adapted to cooperate with the housing of the power tool to limit the rotation of the rear end portion 200 relative to the housing of the power tool. Specifically, two anti-rotation protrusions 250 are provided on the outer sidewall of the rear end portion 200. The two anti-rotation protrusions 250 are symmetrically arranged on the rear end portion 200. The anti-rotation protrusion 250 is located on the side of the rear end portion 200 away from the front end portion 100, and the anti-rotation protrusion 250 extends along the insertion direction.

[0042] As Figures 6-7 shown, the present application further provides a power tool, which includes a housing 400 and the above gearbox. Four third screw holes 410 are provided on the housing 400. The positions of the third screw holes 410 correspond to the first screw hole 111 and the second screw hole 211. The fixing bolt 300 is adapted to pass through the first screw hole 111 and the second screw hole 211 and then connect to the third screw hole 410, so that while connecting the front end portion 100 and the rear end portion 200, the fixing bolt 300 can mount the gearbox on the housing 400. An anti-rotation groove 420 for cooperating with the anti-rotation protrusion 250 is further formed on the housing 400. The two anti-rotation protrusions 250 are respectively embedded in the two anti-rotation grooves 420, thereby restricting the rotation of the gearbox relative to the housing 400.

[0043] The basic principles, main features and advantages of the present application have been described above. Those skilled in the art of this industry should understand that the present application is not limited by the above embodiments. What is described in the above embodiments and the specification is only the principle of the present application. Without departing from the spirit and scope of the present application, the present application will have various changes and improvements, and these changes and improvements all fall within the scope of the present application claimed. The scope of protection claimed by the present application is defined by the appended claims and their equivalents.

Claims

1. A gear box for an electric tool, characterized in that: It includes a front end portion, a rear end portion and a fixing bolt for connecting the front end portion and the rear end portion, the front end portion and the rear end portion are respectively provided with a plurality of front fixing portions and rear fixing portions at mutually connected positions, each of the front fixing portions is provided with a first screw hole for the fixing bolt to pass through, and each of the rear fixing portions is provided with a second screw hole corresponding to the first screw hole, and the fixing bolt is suitable for passing through the first screw hole and the second screw hole and then connecting with the screw hole on the power tool housing, so that the gear box can be installed on the housing of the power tool while connecting the front end portion and the rear end portion.

2. The gearbox according to claim 1, characterized in that: A limiting platform is provided on the inner side wall of the connecting end of the front end portion, a first side wall is formed between the limiting platform and the connecting end face of the front end portion, a connecting portion is provided on the connecting end face of the rear end portion, the connecting portion extends toward the front end portion along the plug-in direction, when the front end portion is connected to the rear end portion, the end face of the connecting portion abuts against the limiting platform, and the outer side wall of the connecting portion fits with the first side wall.

3. The gearbox according to claim 2, characterized in that: A connecting tongue is arranged on the connecting end surface of the front end portion, and a connecting slot for movably plugging the connecting tongue is arranged on the outer side wall of the connecting portion. The connecting tongue is a cantilever structure with one end connected to the front end portion and the other end extending toward the rear end portion along the plugging direction, and the connecting slot extends in the direction away from the front end portion along the plugging direction.

4. The gearbox according to claim 2, characterized in that: A closed-loop groove is also formed on the outer side wall of the connecting portion, a sealing member is arranged in the closed-loop groove, and the sealing member is interference-fitted with the closed-loop groove.

5. The gearbox according to claim 4, characterized in that: The sealing member is an O-type gasket, and the cross-sectional diameter of the O-type gasket is larger than the depth and width of the closed-loop groove; The depth of the closed-loop groove refers to the radial dimension of the closed-loop groove along the connecting portion, and the width of the closed-loop groove refers to the axial dimension of the closed-loop groove along the connecting portion.

6. The gearbox according to claim 3 or 4, characterized in that: A plurality of mounting grooves are also provided on the inner side wall of the rear end portion, and the mounting grooves extend along the plug-in direction. The mounting grooves are circumferentially spaced apart on the inner side wall of the rear end portion, and mounting ribs are formed between two adjacent mounting grooves. The mounting ribs are suitable for interference fit with the inner gear ring to realize the connection between the inner gear ring and the rear end portion.

7. The gearbox according to claim 6, characterized in that At least one anti-rotation protrusion is arranged on the outer side wall of the rear end portion, and the anti-rotation protrusion is suitable for cooperating with the power tool housing to limit the rotation of the rear end portion relative to the power tool housing.

8. The gearbox according to claim 7, characterized in that Two anti-rotation protrusions are arranged on the outer side wall of the rear end portion, and the two anti-rotation protrusions are symmetrically arranged on the outer side wall of the rear end portion away from one end of the front end portion, and the two anti-rotation protrusions extend along the plugging direction.

9. The gearbox according to claim 1, characterized in that: The front end portion is made of aluminum alloy, and the rear end portion is made of polyhexamethylene adipamide.

10. An electric tool, characterized in that: It includes a shell and a gear box as described in any one of claims 1 to 9, wherein a plurality of third screw holes are arranged on the shell, and the positions of the third screw holes correspond to the positions of the first screw holes, and the fixing bolts are suitable for passing through the first screw holes and the second screw holes and then connecting with the third screw holes, so that the fixing bolts can connect the front end portion and the rear end portion while the gear box can be installed on the shell.

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