CN216883814U

CN216883814U - Power tool with vibration-proof assembly

Info

Publication number: CN216883814U
Application number: CN202190000143.6U
Authority: CN
Inventors: 爱德温·智毅·陈; 邱小平; 薛展标
Original assignee: Techtronic Cordless GP
Current assignee: Techtronic Cordless GP
Priority date: 2021-02-23
Filing date: 2021-02-23
Publication date: 2022-07-05
Anticipated expiration: 2031-02-23
Also published as: WO2022178661A1; EP4297933A1

Abstract

A power tool, comprising: an outer housing; a motor disposed within the outer housing; an output shaft for performing an operation on a workpiece, the output shaft adapted to be driven by the motor; a bearing configured to support the output shaft; an inner housing disposed at least partially within the outer housing and configured to receive a portion of the bearing; and a vibration preventing assembly configured to reduce vibration transmitted to the outer housing, wherein the vibration preventing assembly includes a first vibration preventing member installed between the bearing and the outer housing, the first vibration preventing member being adapted to be in direct or indirect contact with the bearing and the outer housing without being in direct contact with the inner housing.

Description

Power tool with vibration-proof assembly

Technical Field

The present invention relates to a power tool having an anti-vibration assembly that reduces vibration transmitted to an external housing of the power tool.

Background

Power tools utilize the rotation of a motor to provide useful torque for operations such as cutting, sanding, grinding, material removal, drilling, fastener driving, and the like. However, vibrations in power tools, particularly portable power tools, invariably reduce their operability.

One way to reduce vibration is to provide an elastic membrane on the handle portion that absorbs a portion of the vibration before it is transmitted to the user's hand. However, if the film is not thick enough, the effect is limited. However, if a thicker elastomeric membrane is wrapped around the handle portion of the power tool, not only does it increase manufacturing costs, but it also reduces the user's ergonomics of grasping the handle portion.

Accordingly, it is desirable to provide a power tool having an anti-vibration unit that effectively reduces vibration transmission.

SUMMERY OF THE UTILITY MODEL

According to an aspect of the present invention, there is provided a power tool including:

an outer housing;

a motor disposed within the outer housing;

an output shaft for performing an operation on a workpiece, the output shaft adapted to be driven by the motor;

a support unit configured to support the output shaft such that the output shaft is rotatable with respect to the outer housing;

an inner housing disposed at least partially within the outer housing and configured to receive a portion of the support unit; and

a vibration preventing assembly configured to reduce vibration transmitted to the outer case, wherein the vibration preventing assembly includes a first vibration preventing member installed between the support unit and the outer case, the first vibration preventing member being adapted to be in direct or indirect contact with the support unit and the outer case without being in direct contact with the inner case.

In an embodiment, the first vibration preventing member extends between the support unit and the outer housing in a direction substantially perpendicular to the axial direction of the output shaft.

In an embodiment, the inner housing has an opening through which the first vibration preventing member passes such that the first vibration preventing member extends between the support unit and the outer housing.

In an embodiment, the opening is a notch formed on the inner housing.

In an embodiment, the first vibration preventing member is movable between the outer case and the supporting unit.

In an embodiment, the first vibration preventing member is immovably installed between the outer case and the supporting unit.

In an embodiment, the support unit is a bearing.

In an embodiment, the support unit is a bushing.

In an embodiment, the support unit comprises a bearing and a bushing that is sleeved on and coupled to the bushing.

In an embodiment, the first vibration preventing member is independent from both the supporting unit and the outer casing.

In an embodiment, the first vibration preventing member is integrally formed with at least a part of the outer case by overmolding.

In a further embodiment, the first vibration preventing member is integrally formed with the bush.

In an embodiment, the first vibration preventing member is formed with a groove to engage with at least a portion of the external casing and/or the supporting unit.

In an embodiment, the first vibration preventing member is an elastic element.

In an embodiment, the vibration preventing assembly includes a pair of the first vibration preventing members symmetrically disposed on opposite sides of the supporting unit.

In the embodiment, the first vibration preventing member is a rubber pin.

In an embodiment, the outer housing includes a groove or a sleeve to receive the end portion of the first anti-vibration member.

In an embodiment, the first vibration preventing member is in contact with the outer case and/or the supporting unit via an intermediate damper.

In an embodiment, the vibration preventing assembly further includes a second vibration preventing member disposed between the inner housing and the outer housing at a position around the output shaft.

In an embodiment, the vibration preventing assembly further includes a third vibration preventing member disposed around the motor between the inner case and the outer case.

Drawings

Embodiments of the utility model will now be described, by way of example, with reference to the accompanying drawings, in which:

fig. 1 is a perspective view showing a power tool including a vibration preventing assembly and an inner housing of the power tool, in which an outer housing is hidden, according to a first embodiment of the present invention.

Fig. 2 is a cross-sectional view of the power tool of fig. 1 with an outer housing taken along plane a-a'.

Fig. 3 is a right side elevational view of the power tool of fig. 1 with one half of the outer housing.

Fig. 4 is a cross-sectional view showing a power tool including a vibration preventing assembly and an internal housing of the power tool according to a second embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENT (S) OF INVENTION

The present invention relates to a power tool provided with a vibration preventing assembly to effectively reduce transmission of vibration in the power tool.

Referring to fig. 1, the embodiment shows a vibration preventing assembly as a constituent part of a power tool according to the present invention. In this embodiment, the power tool is a portable power tool having: an inner housing 100; an output shaft 200 driven by a motor (not shown) to perform an operation on a workpiece (not shown); a bearing 310 partially supported by the inner housing 100 and supporting the output shaft 200. For example, the bearing 310 is a needle bearing. The portable power tool also has an outer housing 700 (shown in fig. 2 and 3) to receive at least a portion of the inner housing 100. A portion of the outer housing 700 is configured as a handle portion (not shown) that can be grasped by a user.

When the power tool is operated, the motor and the output shaft 200 generate vibrations. In particular, the vibrations are generated by the output shaft and moving parts (not shown) in the vicinity of the output shaft. The vibration is transmitted to the inner housing 100 which is in indirect contact with the output shaft. Thus, the vibration may be transmitted to the outer case 700 receiving the inner case 100.

In order to eliminate or at least reduce the transmission of vibrations to the outer housing (i.e., to the handle portion of the power tool), a vibration isolator assembly is provided for a power tool in the present invention.

In this first embodiment, the vibration preventing assembly includes a pair of first vibration preventing members 410. Each first vibration preventing member 410 is installed between the bearing 310 and the outer housing 700, and the first vibration preventing member is in direct contact with the bearing and the outer housing, not with the inner housing 100. The inner housing 100 is provided with an opening 110 through which the first vibration preventing member 410 passes such that the first vibration preventing member 410 extends between the outer housing 700 and the bearing 310 such that the first vibration preventing member 410 bypasses the inner housing 100. This is to ensure that the first vibration preventing member 410 directly absorbs at least part of the vibration energy generated mainly by the output shaft and the moving parts in the vicinity of the output shaft before the vibration energy is transmitted to the inner casing 100 and/or the outer casing 700. In another embodiment, the first vibration preventing member is in direct contact with the outer housing and/or the bearing via an intermediate damper.

The opening 110 in the inner case 110 is configured as a recess so as to minimize the possibility of contact between the first vibration preventing member 410 and the inner case 100. The recess has a general "U" shape. In other embodiments, the opening 110 may be a closed opening in any regular or irregular shape.

In this first embodiment, the two first vibration preventing members 410 are configured as a pair of elastic elements, such as a pair of rubber pins. The pair of rubber pins are symmetrically arranged on opposite sides of the bearing 310, and extend in opposite directions from the bearing 310 to the outer housing 700 in a direction perpendicular to the axial direction of the output shaft 200 and perpendicular to the axial direction of the inner housing 100. The skilled person will understand that in variants of the utility model, the inner casing 100 may or may not be symmetrical, and that "axial direction of the inner casing 100" refers to a direction perpendicular to the radial direction of the inner casing 100.

Referring to fig. 2, the outer housing 700 is provided with a groove or sleeve 710 to receive one end of each first vibration preventing member 410 at each side of the bearing 310. The other end portion of the first vibration preventing member 410 protrudes from the outer circumference of the bearing 310 such that the first vibration preventing member 410 is movable between the outer case 700 and the bearing 310. This enables the first vibration preventing member 410 to self-adjust to further release the absorbed excessive vibration energy when the first vibration preventing member 410 is excessively compressed and/or excessively deformed. In a variation of the embodiment, the first anti-vibration member is immovably mounted between the outer housing and the bearing.

Referring to fig. 1 and 3, the vibration preventing assembly further includes a second vibration preventing member 500 disposed between and in contact with the inner and

outer housings

100 and 700 so as to reduce transmission of vibration from the inner housing 100 to the outer housing 700. In this embodiment, the second vibration preventing member 500 is in direct contact with a first end of the inner housing 100 near an end tool (not shown) coupled to the output shaft to perform work on a workpiece. The second vibration preventing member 500 is disposed around the output shaft like the first vibration preventing member 400. In a variation of the embodiment, the second vibration preventing member may be in contact with the first end portion of the inner housing via the first intermediate member. In the presence of the second vibration preventing member 500, the inner case 100 is physically isolated from the outer case 700, and transmission of vibration between the inner case and the outer case is further reduced. The shape of the second vibration preventing member 500 may be customized to fit at least partially at the first end in the space between the outer case 700 and the inner case 100.

Referring to fig. 1 and 3, the vibration preventing assembly further includes a third vibration preventing member 600 disposed between and contacting the inner and

outer housings

100 and 700 so as to reduce transmission of vibration from the inner housing 100 to the outer housing 700. The third vibration prevention member 600 contacts the second end of the inner case 100 via the first intermediate member 610. The third vibration prevention member 600 is positioned around the motor. In a variation of the embodiment, the third vibration prevention member 600 may be in direct contact with the second end of the inner case 100. Like the second vibration prevention member 500, the third vibration prevention member 600 physically isolates the inner case 100 from the outer case 700 and reduces vibration transmission therebetween. The third vibration prevention member 500 may be shaped to at least partially fit at the second end in the space between the outer case 700 and the inner case 100.

In the present application, the terms "first end of the inner housing" and "second end of the inner housing" are used only for the purpose of distinguishing one from another, and may or may not be the distal end of the inner housing.

Fig. 4 shows a second embodiment of the present invention, which shows an alternative arrangement of the first vibration preventing member. In this second embodiment, the inner housing, the output shaft, the outer housing, the opening of the inner housing, the second vibration prevention member, and the third vibration prevention member may be the same as those in the first embodiment. The same reference numerals as in the first embodiment are used to denote them, and the description will not be repeated here.

In this second embodiment, the support unit is a flanged bush 320 that is partially supported by the inner housing 100 and supports the output shaft 200. The anti-vibration assembly comprises a first anti-vibration member 420, such as a rubber ring, adapted to engage at least a portion of the flanged bushing 320. The first vibration preventing member 420 is provided at one side with a groove to receive the flange of the flanged bush 320, and the opposite side of the first vibration preventing member 420 is in contact with the inner wall of the outer case 700. In an alternative embodiment, the first vibration preventing member may be integrally formed with the bush.

At least a portion of the first vibration prevention member 420 and the flanged bushing 320 extend through the opening 110 formed in the inner housing 100 and do not directly contact the inner housing 100 to ensure that the first vibration prevention member 420 directly absorbs at least a portion of the vibrational energy of the motor and output shaft before it is transmitted to the outer housing 700.

As in the first embodiment, the outer case 700 may be provided with a groove or a sleeve 710 to receive one end of each first vibration preventing member 420.

(disclaimer of exemption)

Throughout the specification and claims, unless the context requires otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the utility model as shown in the specific embodiments without departing from the spirit or scope of the utility model as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

For example, in an alternative embodiment (not shown), the first vibration preventing member is an integral member having a plurality of different shapes. In another embodiment, the vibration preventing assembly includes more than two first vibration preventing members. The or each first anti-vibration member is arranged in direct or indirect contact with the outer circumference of the bearing and with the inner surface of the outer housing. When the power tool is operated, the first anti-vibration member supports vibrations particularly in a direction in which the first anti-vibration member extends.

In the embodiment shown in fig. 1 to 4, the first vibration preventing member is shown as a rubber pin or a rubber ring independent of the bearing and the outer housing. It should be recognized that other types of anti-vibration members can also be used with the present invention. For example, the first vibration preventing member may be a coil spring in addition to being made of an elastic material. In a further variant, the first anti-vibration member may be made using overmolding and be part of the outer casing.

In the embodiment shown in fig. 1 to 4, the support unit is a non-flanged bearing 310 or a flanged bushing 320. In further variants, the support unit may be a flanged bearing or a non-flanged bush, or may comprise a bearing and a bush fitted to the bearing.

In the embodiment shown in fig. 1 to 4, the power tool is a multi-function tool. However, those skilled in the art will recognize that the vibration preventing structure of the present invention can also be applied to other types of power tools.

Unless otherwise indicated, any reference to prior art contained herein is not an admission that the information is common general knowledge.

Claims

1. A power tool, comprising:

an outer housing;

a motor disposed within the outer housing;

2. The power tool according to claim 1, wherein the first anti-vibration member extends between the support unit and the outer housing in a direction substantially perpendicular to the axial direction of the output shaft.

3. The power tool according to claim 1 or 2, wherein the inner housing has an opening through which the first anti-vibration member passes such that the first anti-vibration member extends between the support unit and the outer housing.

4. The power tool according to claim 3, wherein the opening is a notch formed on the inner housing.

5. The power tool according to any one of the preceding claims, wherein the first anti-vibration member is movable between the outer housing and the support unit.

6. The power tool according to any one of the preceding claims, wherein the first anti-vibration member is immovably mounted between the outer housing and the support unit.

7. The power tool according to any one of claims 1 to 6, wherein the support unit is a bearing.

8. The power tool according to any one of claims 1 to 6, wherein the support unit is a bushing.

9. The power tool according to any one of claims 1 to 6, wherein the support unit includes a bearing and a bushing that is fitted over and coupled to the bushing.

10. The power tool according to any one of claims 1 to 9, wherein the first anti-vibration member is independent of both the support unit and the outer housing.

11. The power tool according to any one of claims 1 to 9, wherein the first anti-vibration member is integrally formed with at least a part of the outer housing by overmolding.

12. The power tool according to claim 9, wherein the first vibration preventing member is integrally formed with the bushing.

13. The power tool according to any one of the preceding claims, wherein the first anti-vibration member is formed with a groove to engage with at least a part of the external housing and/or the support unit.

14. The power tool according to any one of the preceding claims, wherein the first anti-vibration member is an elastic element.

15. The power tool according to any one of the preceding claims, wherein the anti-vibration assembly includes a pair of the first anti-vibration members symmetrically arranged on opposite sides of the support unit.

16. The power tool according to claim 12, wherein the first anti-vibration member is a rubber pin.

17. The power tool according to any one of the preceding claims, wherein the outer housing includes a groove or sleeve to receive an end portion of the first anti-vibration member.

18. The power tool according to any one of the preceding claims, wherein the first anti-vibration member is in contact with the outer housing and/or the support unit via an intermediate damper.

19. The power tool according to any one of the preceding claims, wherein the anti-vibration assembly further comprises a second anti-vibration member disposed between the inner housing and the outer housing at a position around the output shaft.

20. The power tool according to any one of the preceding claims, wherein the anti-vibration assembly further comprises a third vibration prevention member disposed around the motor between the inner housing and the outer housing.