CN219054301U - Axial impact structure and power tool - Google Patents

Abstract

The utility model relates to the technical field of power tools, and particularly discloses an axial impact structure and a power tool. The axial impact structure comprises a transmission shaft and an output shaft which are coaxially arranged, the upper end face of the transmission shaft is in contact fit with the lower end face of the output shaft, at least two convex parts are uniformly distributed on the lower end face of the output shaft along the circumferential direction, impact grooves and impact bosses are arranged on the upper end face of the transmission shaft at intervals along the circumferential direction, the impact bosses are provided with impact faces with certain arc lengths, and the number of the impact grooves and the number of the impact bosses are integer multiples of the convex parts. Compared with the prior art, the axial impact structure of the structure has lower impact frequency, more abrupt axial impact force, larger impact force and better impact effect. In the continuous separation and contact matching process of the convex part, the impact groove and the impact boss, the resistance point is fewer, the integral resistance and abrasion are smaller, the service life is longer, and the energy consumption and the cost are lower.

Description

Axial impact structure and power tool

Technical Field

The utility model relates to the technical field of power tools, in particular to an axial 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. Common impact power tools are configured with either axial impact structures or radial impact structures.

Fig. 1 and 2 show an axial impact structure in the prior art, which includes a lower impact seat 30 fixedly arranged and an upper impact seat 20 arranged opposite to the lower impact seat 30, wherein the upper impact seat 20 is fixedly arranged on an output shaft 10, the output shaft 10 is driven by a power source to perform rotational movement, and the output shaft has a certain movement space in the 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 has the following defects:

(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.

Disclosure of Invention

The utility model aims to provide an axial impact structure and a power tool with improved structure, so as to solve the defects in the prior art.

In order to solve the technical problems, the technical scheme provided by the utility model is as follows: the utility model provides an axial impact structure, includes transmission shaft and the output shaft of coaxial setting, the up end of transmission shaft with the lower terminal surface contact cooperation of output shaft, rotary motion can be done to the transmission shaft, rotary motion and axial motion can be done to the output shaft, be provided with two at least convex parts along circumferencial direction equipartition on the lower terminal surface of output shaft, be provided with on the up end of transmission shaft along circumferencial direction interval and strike recess and impact boss, impact boss is provided with the impact surface that has certain arc length, impact recess and impact boss's quantity is the integer multiple of convex part.

In a preferred embodiment, the protrusions are rolling elements.

In a preferred embodiment, the protruding portion is a steel ball, a containing groove for containing the steel ball is formed in the lower end face of the output shaft, 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 protruding portion is integrally formed on the lower end surface of the output shaft.

In a preferred embodiment, the impact groove is provided with a guide surface at a position where at least one end of the impact groove abuts the impact boss.

In a preferred embodiment, guide surfaces are arranged at the positions where the two ends of the impact groove are adjacent to the impact boss.

In a preferred embodiment, the arc length of the impact groove is greater than the arc length of the impact boss.

The embodiment also provides a power tool, which at least comprises the axial impact structure.

In a preferred embodiment, the output shaft is provided with a first pin hole extending inwards from the center of the lower end surface, the transmission shaft is provided with a second pin hole extending inwards from the center of the upper end surface, and the transmission shaft 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 in clearance fit with at least the first pin hole or the second pin hole.

Compared with the prior art, the axial impact structure and the power tool have 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.

Drawings

FIG. 1 is a schematic view of a prior art power tool incorporating an axial impact structure;

FIG. 2 is a schematic view of an exploded view of an axial impact structure of the power tool of FIG. 1;

FIG. 3 is a schematic view of a part of a power tool incorporating an axial impact structure according to the present embodiment;

fig. 4 is a schematic view showing an explosion state structure of the axial impact structure in this embodiment.

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. 3 and 4, an axial impact structure applied to a power tool of the present embodiment includes a transmission shaft 40 and an output shaft 10 coaxially disposed, wherein the transmission shaft 40 is driven by a power source to perform rotational movement, and the output shaft 10 has a certain axial movement space to perform rotational movement and axial movement. 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, the upper end surface of the transmission shaft 40 is in contact with the lower end surface of the output shaft 10. As a special feature of this embodiment, 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. 2, so that after the axial impact, the steel ball is kept for a certain time in the high axial pressure state formed by the axial impact, 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.

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 (10)

1. The utility model provides an axial impact structure, its characterized in that, including coaxial transmission shaft and the output shaft that sets up, the up end of transmission shaft with the lower terminal surface contact cooperation of output shaft, rotary motion can be done to the transmission shaft, rotary motion and axial motion can be done to the output shaft, be provided with two at least convex parts along the circumferencial direction equipartition on the lower terminal surface of output shaft, be provided with on the up end of transmission shaft along the circumferencial direction interval and strike recess and impact boss, impact boss is provided with the impact surface that has certain arc length, impact recess and impact boss's quantity is the integer multiple of convex part.

2. The axial impact structure of claim 1, wherein the protrusions are rolling elements.

3. The axial impact structure according to claim 2, wherein the convex portion is a steel ball, and a lower end surface of the output shaft is provided with a receiving groove for receiving the steel ball, the steel ball being rollable in the receiving groove.

4. An axial impact structure according to claim 3, 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 smaller than the diameter of said steel ball.

5. The axial impact structure according to claim 1, wherein the convex portion is integrally formed on a lower end face of the output shaft.

6. An axial impact structure according to any one of claims 1-5, wherein at least one end of the impact groove is provided with a guide surface at a position adjacent to the impact boss.

7. The axial impact structure according to claim 6, wherein both ends of the impact groove are provided with guide surfaces at positions adjacent to the impact boss.

8. The axial impact structure of any one of claims 1-5 or 7, wherein the arc length of the impact groove is greater than the arc length of the impact boss.

9. A power tool comprising at least an axial impact structure according to any one of claims 1-8.

10. The power tool according to claim 9, wherein the output shaft is provided with a first pin hole extending inward from a center of the lower end surface, the drive shaft is provided with a second pin hole extending inward from a center of the upper end surface, and further comprising a connecting pin fittingly connected to the first pin hole and the second pin hole, respectively, the connecting pin being clearance-fitted with at least the first pin hole or the second pin hole.

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