CN219054300U

CN219054300U - Combined impact structure and power tool

Info

Publication number: CN219054300U
Application number: CN202320006331.0U
Authority: CN
Inventors: 李双群; 刘玉宏; 张焕发; 骆锐
Original assignee: Zhejiang Xinhe Powder Metallurgy Products Co ltd
Current assignee: Zhejiang Xinhe Powder Metallurgy Products Co ltd
Priority date: 2023-01-03
Filing date: 2023-01-03
Publication date: 2023-05-23
Anticipated expiration: 2033-01-03

Abstract

The utility model relates to the technical field of power tools, and particularly discloses a combined impact structure and a power tool. The combined impact structure comprises an output shaft, a transmission shaft, an axial impact structure, a radial impact structure and a return spring, wherein the axial impact structure comprises at least two convex parts which are uniformly arranged on the lower end face of the output shaft along the circumferential direction, and impact grooves and impact bosses which are arranged on the upper end face of the transmission shaft at intervals along the circumferential direction; the radial impact structure comprises impact wings symmetrically arranged on the output shaft and impact seats sleeved on the outer side of the transmission shaft and capable of axially moving relative to the transmission shaft. The combined impact structure of the structure is integrated with the axial impact structure and the radial impact structure, so that not only can axial impact be realized, but also radial impact can be realized, and the working efficiency of the power tool is further improved.

Description

Combined impact structure and power tool

Technical Field

The utility model relates to the technical field of power tools, in particular to a combined impact structure and a power tool.

Background

In some applications, when the resistance encountered by the electric wrench or the electric drill is too large, the power source output by the electric wrench or the electric drill is not enough to meet the requirement. Therefore, a power tool having an impact function has been developed, and when the depth of penetration of a screw, a drill, etc., increases and external resistance increases, an impact force is generated by the impact structure, thereby making the application range of the electric wrench or the electric drill wider.

Conventional impact power tools are configured with only axial impact structures or radial impact structures, i.e., existing impact power tools can only achieve radial impact or axial impact. Compared with a non-impact power tool, the performance of the non-impact power tool is obviously improved, and the application range is wider. However, a power tool having only a radial impact or axial impact function still has room for improvement in performance.

Disclosure of Invention

The utility model aims to provide a combined impact structure with an axial impact function and a radial impact function and a power tool, so as to further improve the performance and the application range of the impact power tool.

In order to solve the technical problems, the technical scheme provided by the utility model is as follows: a modular impact structure comprising at least:

an output shaft configured to be rotatable and axially movable

A transmission shaft configured to be capable of rotating, an upper end surface of the transmission shaft being in contact engagement with a lower end surface of the output shaft,

the axial impact structure comprises at least two convex parts which are uniformly arranged on the lower end face of the output shaft along the circumferential direction, and impact grooves and impact bosses which are arranged on the upper end face of the transmission shaft at intervals along the circumferential direction, wherein the number of the impact grooves and the number of the impact bosses are integer multiples of that of the convex parts;

the radial impact structure comprises impact wings symmetrically arranged on an output shaft and impact seats sleeved on the outer side of the transmission shaft and capable of axially moving relative to the transmission shaft, the impact wings extend radially outwards from the position, adjacent to the lower end, of the output shaft, a pair of impact blocks are symmetrically arranged on the end face, facing to the output shaft, of the impact seats, impact grooves for accommodating the impact wings are arranged between the adjacent impact blocks, and the axial movement space of the impact seats is larger than the axial depth of the impact grooves; and

and the reset spring is arranged on one side of the impact seat, which is far away from the output shaft.

In a preferred embodiment, the protruding portion is integrally formed on the lower end surface of the output shaft; or, the convex part is a steel ball, the lower end face of the output shaft is provided with a containing groove for containing the steel ball, and the steel ball can roll in the containing groove.

In a preferred embodiment, the depth of the receiving groove is larger than the radius of the steel ball, and the diameter of the opening of the receiving groove is smaller than the diameter of the steel ball.

In a preferred embodiment, the impact boss is provided with an impact surface having an arc length, the arc length of the impact groove being greater than the arc length of the impact boss.

In a preferred embodiment, the impact piece is arranged as a guide surface adjacent to the striking surface of the impact groove and/or the side of the impact wing.

In a preferred embodiment, the impact seat is provided with an inner hole for accommodating the transmission shaft, and a transmission structure is arranged between the inner hole and the transmission shaft.

In a preferred embodiment, the transmission structure comprises a pair of transmission grooves symmetrically arranged on the inner wall of the inner hole and extending along the axial direction, and a pair of transmission parts arranged on the outer wall of the transmission shaft and matched with the transmission grooves.

In a preferred embodiment, the transmission part is a steel ball, and the outer wall of the transmission shaft is provided with a containing groove for containing the steel ball.

In a preferred embodiment, the side of the impact seat remote from the output shaft is provided with a spring receiving cavity extending axially from the end face.

The power tool at least comprises the combined impact structure, the output shaft is provided with a first pin hole extending inwards from the center of the lower end face, the transmission shaft is provided with a second pin hole extending inwards from the center of the upper end face, and the power tool further comprises a connecting pin which is respectively connected with the first pin hole and the second pin hole in an adapting mode, and the connecting pin is at least in clearance fit with the first pin hole or the second pin hole.

The combined impact structure and the power tool of the embodiment, wherein the combined impact structure is integrated with the axial impact structure and the radial impact structure, so that not only can axial impact be realized, but also radial impact can be realized, and the working efficiency of the power tool is further improved.

Drawings

FIG. 1 is a schematic view showing a partial structure of a power tool provided with a combined impact structure according to the present embodiment;

FIG. 2 is a schematic diagram showing an explosion state of the radial impact structure in the present embodiment;

FIG. 3 is a schematic view showing an explosion state structure of the axial impact structure in the present embodiment;

FIG. 4 is a schematic view of a prior art power tool incorporating an axial impact structure;

fig. 5 is a schematic view of an exploded state structure of the axial impact structure in the power tool of fig. 4.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the utility model.

In the description of the present utility model, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", "inner", "outer", etc., are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, integrally connected, or detachably connected; may be a communication between the interiors of two elements; may be directly or indirectly through an intermediate medium, and the specific meaning of the terms in the present utility model will be understood by those skilled in the art in specific cases.

As shown in fig. 1 to 3, a combined impact structure applied to a power tool of the present embodiment includes a transmission shaft 40 and an output shaft 10 coaxially arranged, and an upper end surface of the transmission shaft 40 is in contact fit with a lower end surface of the output shaft 10. The transmission shaft 40 is driven by a power source to perform rotary motion, and the output shaft 10 has a certain axial motion space and can perform rotary motion and axial motion. It should be noted that, the connection between the transmission shaft and the power source and the power transmission between the transmission shaft and the output shaft are not the utility model points of the present application, and thus are not described in detail herein.

In this embodiment, the output shaft 10 is provided with a first pin hole 11 extending inward from the center of the lower end surface, and the drive shaft 40 is provided with a second pin hole 44 extending inward from the center of the upper end surface. Wherein the connecting pin 50 is adapted to be connected with the first pin hole 11 and the second pin hole 44, respectively. And, the connecting pin 50 is clearance fitted with at least the first pin hole or the second pin hole, so that the output shaft 10 can move both axially and rotationally.

In this embodiment, as shown in fig. 1-3, at least two protrusions are uniformly distributed on the lower end surface of the output shaft 10 along the circumferential direction, and impact grooves 41 and impact bosses 42 are disposed on the upper end surface of the transmission shaft 40 at intervals along the circumferential direction.

Wherein the impact boss 42 is provided with an impact surface having an arc length, preferably the arc length of the impact groove is greater than the arc length of the impact boss. And, the number of the impact grooves 41 and the impact bosses 42 is an integer multiple of the protruding portions.

Preferably, in this embodiment, the protrusions are rolling elements, preferably steel balls 60, and the number is 2. Correspondingly, in this embodiment, the number of the impact grooves 41 and the impact bosses 42 is 4, which is 2 times the number of the steel balls.

In this embodiment, the lower end surface of the output shaft 10 is provided with 2 receiving grooves 12 for receiving the steel balls 60, and the steel balls 60 are rollably disposed in the receiving grooves 12.

Preferably, the depth of the accommodating groove 12 is larger than the radius of the steel ball 60, and the diameter of the opening of the accommodating groove is smaller than the diameter of the steel ball 60, so that the steel ball cannot fall out of the accommodating groove after the arrangement.

In the axial impact structure according to the present embodiment, during operation, the steel ball 60 is located in the impact groove 41, and when the depth of penetration of the screw, the drill bit, etc. increases and the external resistance increases, the steel ball 60 is separated from the impact groove 41 and contacts with the impact surface of the impact boss 42, and during this process, the output shaft 10 is driven to move forward to form an axial impact.

In this embodiment, the impact boss 42 is provided with an impact surface having a certain arc length, where the "certain arc length" is a certain distance that the steel ball can slide on the impact surface compared with the tooth tip in the prior art shown in fig. 5, so that after the axial impact, the steel ball is kept in the high axial pressure state formed by the axial impact for a certain time, and especially for the impact electric drill, the impact effect formed by the axial direction is better.

The convex portion described in this embodiment may be integrally formed on the lower end surface of the output shaft 10. In comparison, in the scheme that the convex part is a rolling body, rolling friction is arranged between the rolling body and the impact groove and the impact boss, so that the resistance is smaller, the power provided by a required power source is smaller, the cost and the energy consumption are saved, the abrasion is smaller, and the service life is longer.

Preferably, in this embodiment, guide surfaces 43 are provided at positions where both ends of the impact groove 41 abut against the impact boss 42. The purpose of the guide surface 43 is to make it easier for the steel ball to come out of the impact groove. The guide surfaces 43 are provided at both ends of the impact groove 41 so that the axial impact structure is suitable for a power tool that can be rotated in the forward and reverse directions. If the guide surface 43 is provided only at one end of the striking groove 41, it is applicable only to a power tool rotating in one direction.

Fig. 4 and 5 show an axial impact structure in the prior art, which includes a lower impact seat 30 fixedly disposed and an upper impact seat 20 disposed opposite to the lower impact seat 30, wherein the upper impact seat 20 is fixedly disposed on an output shaft 10, the output shaft 10 is driven by a power source to perform a rotational motion, and the output shaft has a certain motion space in an axial direction.

The end surface of the lower impact seat 30 facing the upper impact seat 20 is provided with a lower impact end surface gear ring 31, and the end surface of the upper impact seat 20 facing the lower impact seat 30 is provided with an upper impact end surface gear ring 21 which is in fit engagement with the lower impact end surface gear ring 31. In the working process, the output shaft 10 rotates under the action of a power source, and the lower impact end face gear ring 31 and the upper impact end face gear ring 21 are repeatedly meshed and separated along with the rotation of the output shaft 10, so that the output shaft 10 axially reciprocates while rotating, and axial impact is realized.

The axial impact structure of the above prior art has the drawbacks that:

(1) The lower impact face gear ring 31 is in gear engagement with the upper impact face gear ring 21, and the frequency of impact is high during the engagement and disengagement process, so that the duration of the impact state or the non-impact state is short, and the impact effect is to be improved.

(2) Based on the structural characteristics of the gears, the engagement and disengagement processes are linear, and the generated impact force is small.

(3) When the power tool is in an impact environment for a long time, the teeth of the impact end face gear ring 31 and the upper impact end face gear ring 21 are inevitably worn, the impact effect is affected after the wear, and the service life of the axial impact structure based on gear engagement is short.

(4) In the process of the engagement and disengagement of the lower impact face gear ring 31 and the upper impact face gear ring 21, each tooth generates resistance, the resistance points are more, the overall resistance is larger, and the required power source power is larger.

Compared with the axial impact structure in the prior art, the axial impact structure of the embodiment has the following beneficial effects:

(1) The number of the convex parts, the impact grooves and the impact bosses in the circumferential direction is smaller, the frequency of axial impact is far lower than that of the impact in the gear meshing mode, but the duration time of the impact state or the non-impact state is far higher than that of the axial impact structure in the gear meshing mode, so that the impact effect is better.

(2) Based on the axial fall between the impact groove and the impact boss, the generated axial impact force is more abrupt in the process of continuous contact fit between the convex part and the impact groove and the impact boss, so that the impact force is larger, and the impact effect is better.

(3) When the power tool is in the impact environment for a long time, compared with the engagement and disengagement between the gear rings, the abrasion between the convex part and the impact groove and the impact boss in the embodiment is smaller, the service life is longer, the structure is simpler, and the production cost is lower.

(4) In the continuous separation and contact matching process of the convex part, the impact groove and the impact boss, the resistance points are fewer, the overall resistance is smaller, the required power of the power source is smaller, and the energy consumption and the cost can be saved more.

(5) The axial impact structure is arranged between the end faces of the transmission shaft and the output shaft, so that no extra space is occupied, the axial impact structure can be combined with a radial impact structure in the prior art, the installation and the use of the existing radial impact structure are not affected, and the combined impact type power tool capable of achieving radial impact and axial impact is formed.

As a feature of the present embodiment, not only the axial impact structure described above is provided, but also the combined impact structure of the present embodiment includes a radial impact structure. As shown in fig. 1 and 2, the radial impact structure includes impact wings 13 symmetrically disposed on the output shaft 10, and an impact seat 70 axially movable with and sleeved on the outside of the drive shaft 40.

Wherein the impact wings 13 extend radially outwards from the position of the output shaft adjacent to the lower end, a pair of impact blocks 72 are symmetrically arranged on the end surface of the impact seat 70 facing the output shaft 10, and an impact groove 73 for accommodating the impact wings 13 is arranged between the adjacent impact blocks 72.

In this embodiment, the impact seat 70 is mounted in the cavity 110 inside the housing 100, and the axial movement space of the impact seat 70 in the cavity 110 is larger than the axial depth of the impact groove 73.

In this embodiment, a return spring 90 is also installed in the cavity 110. Preferably, a spring receiving chamber 75 extending in the axial direction from the end surface is provided on a side of the impact seat 70 away from the output shaft, and one end of a return spring 90 is mounted in the spring receiving chamber 75. By providing the spring receiving chamber 75, the axial length of the return spring can be increased, and a longer return spring can provide a greater elastic force.

In this embodiment, the impact seat 70 is provided with an inner hole 71 for accommodating the transmission shaft 40, and a transmission structure is provided between the inner hole 71 and the transmission shaft 40. In particular to the present embodiment, the driving structure includes a pair of driving grooves 74 symmetrically disposed on the inner wall of the inner hole and extending in the axial direction, and a pair of driving parts disposed on the outer wall of the driving shaft 40 and adapted to the driving grooves 74. Preferably, in this embodiment, the transmission part is a steel ball 80, and the outer wall of the transmission shaft 40 is provided with a receiving groove 45 for receiving the steel ball.

In the combined impact structure of the embodiment, when the external resistance of the power tool is relatively small in the working process, the transmission shaft 40 drives the impact seat 70 to rotate through the transmission structure, the impact wings 13 are positioned in the impact grooves 73, the impact wings 13 are acted on by the impact blocks 72 to drive the output shaft 10 to rotate, and no radial and axial impact is generated. As the depth of penetration of the screw, bit, etc. increases, the external resistance experienced by the power tool increases, and the impact seat 70 gradually displaces axially downward, compressing the return spring 90. The impact seat 70 continuously moves downwards until the impact wings 13 are separated from the impact grooves 73, the upper end face of the impact block 72 passes over the lower end face of the impact wings 13, the impact seat 70 is quickly reset under the reset action of the reset spring 90, and the impact block 72 knocks the impact wings 13, so that one radial impact is realized. In the process that the upper end surface of the impact block 72 passes over the lower end surface of the impact wing 13, the steel ball 60 is separated from the impact groove 41 and contacts with the impact surface of the impact boss 42 due to the continuous high-speed rotation of the transmission shaft, and in the process, the output shaft 10 is driven to move forwards to form an axial impact.

In this embodiment, the striking surface 76 of the impact block 72 abutting the impact groove 73 is provided as a guide surface so that the impact wing can be smoothly removed from the impact groove. As an equivalent, the guide surfaces may also be provided on the sides of the impact wings.

In summary, the foregoing description is only of the preferred embodiments of the utility model, and is not intended to limit the utility model to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the utility model.

Claims

1. A modular impact structure comprising at least:

an output shaft configured to be rotatable and axially movable

2. The modular impact structure of claim 1 wherein said boss is integrally formed on a lower end surface of said output shaft; or, the convex part is a steel ball, the lower end face of the output shaft is provided with a containing groove for containing the steel ball, and the steel ball can roll in the containing groove.

3. The modular impact structure of claim 2 wherein the depth of said receiving groove is greater than the radius of said steel ball and the diameter of the opening of said receiving groove is less than the diameter of said steel ball.

4. The modular impact structure of claim 1 wherein said impact boss is provided with an impact surface having an arc length, said impact groove having an arc length greater than an arc length of said impact boss.

5. A combined impact structure according to claim 1, characterized in that the striking face of the impact block abutting the impact groove and/or the side face of the impact wing are provided as guiding faces.

6. A modular impact structure according to any one of claims 1 to 5, wherein the impact socket is provided with an internal bore for receiving the drive shaft, a drive structure being provided between the internal bore and the drive shaft.

7. The modular impact structure of claim 6 wherein the drive structure includes a pair of symmetrically disposed axially extending drive slots on the inner wall of the bore and a pair of drive portions disposed on the outer wall of the drive shaft and adapted to the drive slots.

8. The modular impact structure of claim 7, wherein the driving portion is a steel ball, and the outer wall of the driving shaft is provided with a receiving groove for receiving the steel ball.

9. A modular impact structure according to any one of claims 1 to 5, wherein the side of the impact seat remote from the output shaft is provided with a spring receiving cavity extending axially from the end face.

10. A power tool comprising at least a combination impact structure according to any one of claims 1-9, said output shaft being provided with a first pin hole extending inwardly from the centre of the lower end face, said drive shaft being provided with a second pin hole extending inwardly from the centre of the upper end face, and further comprising a connecting pin adapted to be connected to the first pin hole and the second pin hole, respectively, said connecting pin being in clearance fit with at least said first pin hole or said second pin hole.