CN214292954U

CN214292954U - Hand-held electric tool and impact mechanism for hand-held electric tool

Info

Publication number: CN214292954U
Application number: CN202022624931.2U
Authority: CN
Inventors: 麻立国; 任宏胜; 黄康; 陈满河
Original assignee: Techtronic Cordless GP
Current assignee: Techtronic Cordless GP
Priority date: 2020-11-13
Filing date: 2020-11-13
Publication date: 2021-09-28
Anticipated expiration: 2030-11-13

Abstract

The utility model discloses a hand-held type electric tool and an impact mechanism for hand-held type electric tool. The hand-held electric tool includes an impact mechanism, a transmission mechanism, and a drive mechanism. The impact mechanism includes: a spindle adapted to receive a tool; a hammer head connected to the spindle and adapted to be operatively connected to a tool; a piston cylinder adapted for reciprocating movement relative to the spindle and the ram; and an anvil connected to the piston cylinder. When the piston cylinder reciprocates, the anvil can impact the hammer head to act on the cutter and the workpiece. The piston cylinder includes a connecting portion having opposing arms. A space is defined between the arm portions. The connecting pin is mounted to the arm portion and extends in the space. The gasket is sleeved on the end of the connecting pin in the space. The support member is fitted over the connecting pin and positioned between the washer and the arm portion to space the washer from the arm portion. The support members can reduce relative movement or friction between the piston cylinder and other components as the piston cylinder is reciprocally driven, thereby reducing the chance of wear or fracture of the piston cylinder.

Description

Hand-held electric tool and impact mechanism for hand-held electric tool

Technical Field

The utility model relates to a hand-held type electric tool, for example electric hammer. The utility model relates to an impact mechanism for hand-held type electric tool.

Background

The electric hammer is a handheld electric tool with wide application. Electric hammers generally have an impact mechanism that can be driven to perform an impact operation. As an example, CN101821062B and CN203956874U disclose electric hammers having impact mechanisms, respectively.

SUMMERY OF THE UTILITY MODEL

Embodiments of the present invention provide a different or improved hand-held power tool, such as but not limited to an electric hammer. Embodiments of the present invention also provide a different or improved (e.g., more durable) impact mechanism for a hand-held power tool.

According to a first aspect of the present invention, there is provided a hand-held electric tool comprising an impact mechanism, a transmission mechanism, and a drive mechanism. The drive mechanism is operatively connected to the impact mechanism through a transmission mechanism. The impact mechanism includes: a spindle adapted to removably receive a tool; a hammer head connected to the spindle and adapted to be operatively connected with a tool when the spindle receives the tool; a piston cylinder adapted for reciprocating movement relative to the spindle and the ram; and an anvil connected to the piston cylinder. When the piston cylinder reciprocates relative to the main shaft and the hammer head, the anvil can impact the hammer head to act on the cutter and further act on a workpiece. The piston cylinder has a connecting portion having opposing arms defining a space therebetween, the arms having mounting portions. The impact mechanism further comprises a connecting pin. The connecting pin is mounted to the arm portion through the mounting portion and extends in the space. The connecting pin is connected with the transmission mechanism. The washer is sleeved on at least one end of the connecting pin, which is located in the space. The support member is fitted over the connecting pin and between the washer and the arm portion to space the washer and the arm portion apart.

In one embodiment of the first aspect, the transmission mechanism has a rocker bearing. The connecting pin may have a through hole that receives the rocker shaft of the rocker bearing. In one example, the rocker shaft presses the washer and the support member against an inner surface of the arm portion of the piston cylinder to at least partially secure the washer and the support member when the rocker shaft passes through the through hole of the connecting pin.

The support member may be made by a rapid mass (mass production) molding process. In one embodiment of the first aspect, the support member is a stamping. In one embodiment of the first aspect, the support member is a laser cutter.

In one embodiment of the first aspect, the support member is a wear member or a wear member.

In one embodiment of the first aspect, the support member is a coating applied to the arm.

In one embodiment of the first aspect, the support member is a metal piece.

In one embodiment of the first aspect, the impact mechanism comprises two washers, which are fitted over opposite ends of the connecting pin in the space. Optionally, the impact mechanism may include additional washers.

In one embodiment of the first aspect, the support member comprises two support members that fit over the connecting pin and between the respective washer and the respective arm portion to space the respective washer and the respective arm portion apart.

In one embodiment of the first aspect, the support member comprises an engagement portion for engaging to the arm portion.

In one embodiment of the first aspect, the joint has a clamping portion for clamping to the arm. For example, the engagement portion has opposing grips that cause the support member to at least partially surround the arm such that the support member is non-rotatably secured to the arm.

In one embodiment of the first aspect, the support member comprises a single support member that is sleeved over the connecting pin and between the washers and the arm portions, respectively, to space the respective washers and the respective arm portions apart.

In one embodiment of the first aspect, the single support member has a generally U-shaped cross-section in plan view. Optionally, the single support member abuts an inner surface of the piston cylinder defining the space such that the support member is non-rotatably fixed to the arm.

In one embodiment of the first aspect, the support member is non-rotatably fixed to the arm.

In one embodiment of the first aspect, the hand-held power tool is an electric hammer.

According to a second aspect of the present invention, an impact mechanism for a hand-held power tool is provided. The impact mechanism includes: a spindle adapted to removably receive a tool; a hammer head connected to the spindle and adapted to be operatively connected with a tool when the spindle receives the tool; a piston cylinder adapted for reciprocating movement relative to the spindle and the ram; and an anvil connected to the piston cylinder. When the piston cylinder reciprocates relative to the main shaft and the hammer head, the anvil can impact the hammer head to act on the cutter. The piston cylinder has a connecting portion having opposing arms defining a space therebetween, the arms having mounting portions. The impact mechanism further comprises a connecting pin. The connecting pin is mounted to the arm portion through the mounting portion and extends in the space. The connecting pin is adapted to be connected to the transmission mechanism such that the impact mechanism is operatively connected to the drive mechanism via the transmission mechanism. The washer is sleeved on at least one end of the connecting pin, which is located in the space. The support member is fitted over the connecting pin and between the washer and the arm portion to space the washer and the arm portion apart.

The support member may be made by a rapid mass (mass production) molding process. In one embodiment of the second aspect, the support member is a stamping. In one embodiment of the second aspect, the support member is a laser cutter.

In one embodiment of the second aspect, the support member is a wear or wear-resistant member.

In one embodiment of the second aspect, the support member is a coating applied to the arm.

In one embodiment of the second aspect, the support member is a metal piece.

In one embodiment of the second aspect, the impact mechanism comprises two washers, which are fitted over opposite ends of the connecting pin in the space. Optionally, the impact mechanism may include additional washers.

In one embodiment of the second aspect, the support member comprises two support members that fit over the connecting pin and are each located between a respective washer and a respective arm portion to space the respective washer and the respective arm portion apart.

In one embodiment of the second aspect, the support member comprises an engagement portion for engaging to the arm portion.

In one embodiment of the second aspect, the joint has a clamping portion for clamping to the arm. For example, the engagement portion has opposing grips that cause the support member to at least partially surround the arm such that the support member is non-rotatably secured to the arm.

In one embodiment of the second aspect, the support member comprises a single support member that is sleeved over the connecting pin and between the washers and the arm portions, respectively, to space the respective washers and the respective arm portions apart.

In one embodiment of the second aspect, the single support member has a generally U-shaped cross-section in plan view. Optionally, the single support member abuts an inner surface of the piston cylinder defining the space such that the support member is non-rotatably fixed to the arm.

In one embodiment of the second aspect, the support member is non-rotatably fixed to the arm.

In one embodiment of the second aspect, the hand-held power tool is an electric hammer.

According to a third aspect of the present invention, an impact mechanism for a hand-held power tool is provided. The impact mechanism includes a piston cylinder assembly. The piston cylinder assembly has: a piston cylinder, a connecting pin, a washer, and a support member. The piston cylinder includes a connecting portion having opposing arms defining a space therebetween, the arms having a mounting portion. The connecting pin is mounted to the arm portion through the mounting portion and extends in the space. The connecting pin is adapted to be connected to a transmission mechanism. The transmission mechanism is used for connecting the piston cylinder assembly to the driving mechanism for reciprocating motion. The washer is sleeved on at least one end of the connecting pin, which is located in the space. The support member is fitted over the connecting pin and between the washer and the arm portion to space the washer and the arm portion apart.

The support member may be made by a rapid mass (mass production) molding process. In one embodiment of the third aspect, the support member is a stamping. In one embodiment of the third aspect, the support member is a laser cutter.

In one embodiment of the third aspect, the support member is a wear or wear-resistant member.

In one embodiment of the third aspect, the support member is a coating applied to the arm.

In one embodiment of the third aspect, the support member is non-rotatably fixed to the arm.

By sleeving the support member on the connecting pin and spacing the washer from the arm between the washer and the arm, relative movement or friction between the piston cylinder and the washer caused when the piston cylinder is driven at a higher reciprocating frequency can be effectively reduced, thereby reducing the chance of wear and even breakage of the piston cylinder. At the same time, the washer is arranged between the transmission mechanism (such as a rocker shaft of the rocker bearing) and the supporting member, so that the relative movement or friction between the supporting member and the transmission mechanism is reduced, and the abrasion chance of the transmission mechanism is further reduced. In general, the cooperation of the support member, the washer and the piston cylinder makes the impact mechanism (in particular the piston cylinder) more durable and makes the impact operation smoother, and increases the service life of the hand-held power tool.

Drawings

Fig. 1 is a schematic cross-sectional view of an impact mechanism of a conventional electric hammer;

FIG. 2A is a schematic exploded view of a piston cylinder assembly of the impact mechanism of FIG. 1;

FIG. 2B is a schematic view of the piston cylinder assembly of FIG. 2A;

fig. 3 is a schematic exploded view of a piston cylinder assembly for an electric hammer according to an embodiment of the present invention;

FIG. 4A is a schematic cross-sectional view of an electric hammer incorporating the piston cylinder assembly of FIG. 3;

FIG. 4B is another schematic cross-sectional view of an electric hammer incorporating the piston cylinder assembly of FIG. 3;

fig. 5 is a schematic exploded view of a piston cylinder assembly of an impact mechanism for an electric hammer according to another embodiment of the present invention;

FIG. 6A is a schematic cross-sectional view of an electric hammer incorporating the piston cylinder assembly of FIG. 5; and

fig. 6B is another schematic cross-sectional view of an electric hammer incorporating the piston cylinder assembly of fig. 5.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other constructions and of being practiced or of being carried out in various ways.

Detailed Description

Fig. 1 to 2B schematically show an impact mechanism 100 of an electric hammer. The impact mechanism 100 may be driven by a drive mechanism through a transmission mechanism.

The impact mechanism 100 includes a main shaft 104 supported at both ends by bushings or

bearings

102A, 102B. The front end of the spindle 104 defines a space 104S1 for removably receiving a tool (not shown). A tool holder (not shown) may be disposed on the forward end of the main shaft 104 for receiving a tool (e.g., a drill bit). The main shaft 102 defines an inner space 104S2 communicating with the space 104S1 at the middle and rear end portions. The hammer head 106 is disposed in the internal space 104S 2. A piston cylinder 110 having an anvil 108 is at least partially received within the interior space 104S 2. The piston cylinder 104 may be driven to reciprocate within the inner space 104S2 so that an anvil 108 of the piston cylinder strikes the hammer head 106, thereby applying an impact to a tool attached to the front end of the main shaft 104.

The piston cylinder 110 has a cylinder portion 110A and a connecting portion 110B at a rear end. A cylinder portion 110A of a piston cylinder 110 fixedly receives the anvil 108. The connecting portion 110B of the piston cylinder 110 may be connected to a drive mechanism. As shown in fig. 2A and 2B, the connecting portion 110B of the piston cylinder 110 has opposing arm portions 110BA1, 110BA 2. The two arms 110BA1, 110BA2 have circular through holes 110BH1, 110BH2, respectively. Vias 110BH1, 110BH2 are generally aligned (e.g., overlapping in cross-section when viewed from the side). A space is defined between the two arms 110BA1, 110BA 2. The through holes 110BH1, 110BH2 and the spaces are used to receive the connecting pins 112. The connecting pin 112 is used to connect the piston cylinder 110 to the wobble shaft bearing 114 and thus to the drive mechanism so that the piston cylinder 110 can be driven by the drive mechanism to reciprocate relative to the main shaft 102 within the interior space 104S2 of the main shaft 102. The connecting pin 112 has a through hole 112H for receiving the connecting portion of the rocker bearing 114 (the connecting portion 114B of the rocker bearing 114 extends through the through hole 112H). When the connecting pin 112 is mounted to the connecting portion 110B of the piston cylinder 110, two

circular washers

116A, 116B are respectively fitted over both ends of the connecting pin 112 and are respectively located on opposite inner surfaces of the arm portions 110BA1, 110BA 2. The connecting pin 112 and the connecting portion 114B of the rocker bearing 114 are configured and dimensioned such that when the connecting pin 112 receives the connecting portion 114B of the rocker bearing 114, the connecting portion 114B of the rocker bearing 114 locks the

washers

116A, 116B against the inner surfaces of the arms 110BA1, 110BA2, respectively.

The drive mechanism for driving the impact mechanism 100 includes an output shaft 120 supported at both ends by needle bearings 118A and ball bearings 118B, respectively. The output shaft 120 is connected to or is part of a prime mover (not shown), such as an electric motor, to be rotated by the prime mover about the axis of rotation X. The output shaft 120 is drivingly connected to the piston cylinder 110 via the rocker bearing 114. The rocker bearing 114 includes a bearing portion 114A and a connecting portion 114B. The bearing portion 114A is fitted to the output shaft 120 between both ends. The connecting portion 114B of the rocker bearing 114 is inserted through the through hole 112H of the connecting pin as described above. The rocker bearing 114 can be considered a transmission.

In the electric hammer of fig. 1 to 2B, the piston cylinder 110 may be formed of an aluminum alloy material, and the

washers

116A, 116B may be formed of a steel material.

During operation of the impact mechanism 100 of the electric hammer described above, the output shaft 120 is driven by the drive mechanism to rotate about the rotation axis X. Rotation of the output shaft about the axis of rotation X will cause the wobble bearing 114 to move, which in turn drives the piston cylinder 110 via the connector pin 112 to reciprocate relative to the main shaft 104 within the interior space 104S2 of the main shaft 104. This reciprocating motion causes the anvil 108 of the piston cylinder 110 to repeatedly strike the hammer head, thereby applying an impact to the drill bit in the space 104S1 connected to the front end portion of the main shaft. Generally, the drive mechanism will cause the piston cylinder 110 to move at a relatively high reciprocating frequency (e.g., about 5000 bpm). During such high frequency reciprocation, the wobble bearing 114 is likely to cause the

washers

116A, 116B to rotate or move against the inner surfaces of the arms 110BA1, 110BA2 of the piston cylinder 110. This may easily cause wear of the piston cylinder 110 and may even cause breakage of the piston cylinder 110, thereby reducing the service life of the electric hammer.

Fig. 3 is a piston cylinder assembly for an electric hammer according to an embodiment of the present invention. The piston cylinder assembly of fig. 3 is similar to the piston cylinder assembly of fig. 2A and 2B, with the primary difference being that the piston cylinder assembly of fig. 3 further includes a bearing member disposed thereon. The main difference will be mainly described below.

Referring to fig. 3, the piston-cylinder assembly includes a piston cylinder 310, a connecting pin 312,

washers

316A, 316B, and

support members

350A, 350B. The piston cylinder 310 has a cylinder portion and a connecting portion at a rear end. The cylinder portion of the piston cylinder 310 fixedly receives the anvil. The connection of the piston cylinder 310 may be connected to a drive mechanism. The connection portion of the piston cylinder 310 has opposing arm portions 310BA1, 310BA 2. The two arms 310BA1, 310BA2 have circular through holes 310BH1, 310BH2, respectively. Vias 310BH1, 310BH2 are generally aligned (e.g., overlapping in cross-section when viewed from the side). A space is defined between the two arms 310BA1, 310BA 2. The through holes 310BH1, 310BH2 and the spaces are used to receive the connecting pins 312. The connecting pin 312 is used to connect the piston cylinder 310 to the wobble rod bearing and thus to the drive mechanism so that the piston cylinder 310 can be driven by the drive mechanism to reciprocate relative to the main shaft. The connecting pin 312 has a through hole 312H for receiving the connecting portion of the rocker bearing. Two

circular washers

316A, 316B are respectively disposed at opposite ends of the connecting pin 312 adjacent to opposite inner surfaces of the arm portions 310BA1, 310BA2 when the connecting pin 312 is mounted to the connecting portion of the piston cylinder 310.

Support members

350A, 350B are respectively sleeved at both ends of the connecting pin 312 between the opposite inner surfaces of the

washers

316A, 316B and the arms 310BA1, 310BA2 to space the

respective washers

316A, 316B and the

respective arms

316A, 316B apart. The

support members

350A, 350B have a generally flat spacer portion and upper and lower opposing engagement portions extending from the spacer portion. The spacer portion defines a through hole to facilitate the

support members

350A, 350B to be fitted over the connection pin 312. The engaging portions extend partially toward each other to form a gripping portion. The clip portion is such that the

support member

350A, 350B may at least partially surround the arm 310BA1, 310BA2 and thus be non-rotatably secured to the arm 310BA1, 310BA 2. The

support members

350A, 350B are stamped parts, which may be made of metal and have wear or wear resistance. The connecting portion of the connecting pin 312 and the rocker bearing is configured and dimensioned such that when the connecting pin 312 receives the connecting portion of the rocker bearing, the connecting portion of the rocker bearing locks the

support members

350A, 350B against the inner surfaces of the arm portions 310BA1, 310BA 2. The piston cylinder 310 may be formed of an aluminum alloy material and the

washers

316A, 316B may be formed of a steel material.

During operation, the drive mechanism will cause the piston cylinder 310 to move at a high reciprocating frequency. During such high frequency reciprocating motion, the

support members

350A, 350B may effectively reduce relative motion or friction between the piston cylinder 310 and the

washers

316A, 316B as the piston cylinder 310 is driven at higher reciprocating frequencies, thereby reducing the chance of wear or even breakage of the piston cylinder 310. At the same time, the disposition of the

washers

316A, 316B between the drive mechanism (e.g., the rocker shaft of the rocker bearing) and the

support members

350A, 350B reduces the relative movement or friction between the

support members

350A, 350B and the drive mechanism, thereby reducing the chance of wear of the drive mechanism.

Fig. 4A and 4B illustrate an electric hammer incorporating the piston cylinder assembly of fig. 3. The structure of the hammer is similar to that of fig. 1 and will therefore not be described in detail here. In some embodiments, the piston cylinder assembly of fig. 3 may be employed in the electric hammer of fig. 1-2B.

Fig. 5 is a piston cylinder assembly for an electric hammer according to another embodiment of the present invention. The piston cylinder assembly of fig. 5 is similar to the piston cylinder assembly of fig. 3 with the main difference being the support member. Only this major difference will be described below.

Referring to fig. 5, the piston-cylinder assembly includes a piston cylinder 510, a connecting pin 512,

washers

516A, 516B, and a support member 550. The piston cylinder 510 has a cylinder portion and a connecting portion at a rear end. The cylinder portion of the piston cylinder 510 fixedly receives the anvil. The connection of the piston cylinder 510 may be connected to a drive mechanism. The connecting portion of the piston cylinder 510 has opposing arms 510BA1, 510BA 2. The two arms 510BA1, 510BA2 have circular through holes 510BH1, 510BH2, respectively. Vias 510BH1, 510BH2 are generally aligned (e.g., overlapping in cross-section when viewed from the side). A space is defined between the two arms 510BA1, 510BA 2. The through holes 510BH1, 510BH2 and the space are used to receive the connecting pins 512. The connecting pin 512 is used to connect the piston cylinder 510 to the wobble rod bearing and thus to the drive mechanism so that the piston cylinder 510 can be driven by the drive mechanism to reciprocate relative to the main shaft. The connecting pin 512 has a through hole 512H for receiving the connecting portion of the rocker bearing 512H. Two

circular washers

516A, 516B are respectively fitted over both ends of the connecting pin 512 when the connecting pin 512 is mounted to the connecting portion of the piston cylinder 510, and are respectively adjacent to the opposite inner surfaces of the arm portions 510BA1, 510BA 2. A single support member 550, which is generally U-shaped in cross-section, is sleeved over the connection pin 512. The support member 550 has generally flat opposing spacer portions and connecting portions connecting the spacer portions. The spacers are generally parallel to each other and are located between opposing inner surfaces of the

washers

516A, 516B and the arms 510BA1, 510BA2, respectively, to space the

respective washers

516A, 516B and the

respective arms

516A, 516B apart. The spacer defines a through hole to facilitate the support member 550 to be fitted over the connection pin 512. The connecting portion extends substantially perpendicular to the spacer portion at an end of the spacer portion. The support member 550 is sized to abut against the interior surface of the piston cylinder defining the space. Specifically, the support member 550 is sized such that both the spacer and the connector portions thereof may abut against the inner surface of the piston cylinder 510, such that the support member 550 may be non-rotatably secured to the arm portions 510BA1, 510BA 2. The support member 550 is a stamped part, which is made of metal and has wear or abrasion resistance. The connecting portion of the connecting pin 512 and the rocker bearing is configured and dimensioned such that when the connecting pin 512 receives the connecting portion of the rocker bearing, the connecting portion of the rocker bearing locks the spacer portion of the support member 550 against the inner surfaces of the arm portions 510BA1, 510BA 2. The piston cylinder 510 may be formed from an aluminum alloy material, while the

washers

516A, 516B may be formed from a steel material.

Fig. 6A and 6B illustrate an electric hammer incorporating the piston cylinder assembly of fig. 5. The structure of the hammer is similar to that of fig. 1 and will therefore not be described in detail here. In some embodiments, the piston-cylinder assembly of fig. 5 may be employed in the electric hammer of fig. 1-2B.

The above description describes a plurality of embodiments of the electric hammer as a hand-held electric tool of the present invention. It should be understood that the present invention is not limited to an electric hammer, but may be any hand-held power tool having a prime mover and an impact mechanism for performing impact operations. Further, it should be understood that the features of the hand held power tool in one embodiment may be combined with, substituted for, etc. the features of the hand held power tool in another embodiment to provide additional embodiments. The hand-held power tool of the present invention may have a different structure as shown, and may have increased or decreased functions or structural features. For example, the number of support members or washers may be one, two, or more. The support member may be made of metal or other material (e.g., wear/abrasion resistant material). The support member may be formed by a rapid mass (mass) forming process such as, but not limited to, stamping, laser cutting, and the like. Wear resistance/abrasion resistance of the support member. The support member may be a separate component or a coating applied to the connection portion of the piston cylinder. The washer may have a different shape (e.g., non-circular). The piston cylinder may have different configurations, such as a different number of arms. The arm may have a through hole or other mounting portion for mounting the connecting pin. The connecting pin may have other connecting mechanisms to connect with the transmission mechanism. The drive mechanism may be an electric motor or any other type of prime mover. The hand-held power tool may be dc-powered, ac-powered or hybrid ac-dc-powered. It will be appreciated by persons skilled in the art that numerous variations and/or modifications may be made to the invention as shown in the specific embodiments without departing from the scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims

1. An impact mechanism for a hand-held power tool, comprising:

a spindle adapted to removably receive a tool;

a hammer head connected to the spindle and adapted to be operatively connected with a tool when the spindle receives the tool;

a piston cylinder adapted for reciprocating movement relative to the spindle and the ram; and

an anvil connected to the piston cylinder, the anvil being adapted to strike the hammer head to act on the tool when the piston cylinder is reciprocated relative to the spindle and the hammer head;

the method is characterized in that:

the piston cylinder includes a connecting portion having opposing arms defining a space therebetween, the arms having a mounting portion; and is

The impact mechanism further includes:

a connecting pin mounted to the arm portion by the mounting portion and extending in the space, the connecting pin for connection with a transmission mechanism such that the impact mechanism is operatively connected to the drive mechanism by the transmission mechanism;

a washer fitted over at least one end of the connecting pin located in the space; and

a support member that is fitted over the connecting pin and between the washer and the arm portion to space the washer and the arm portion apart.

2. The impact mechanism of claim 1, wherein: the supporting component is a stamping part or a laser cutting part.

3. The impact mechanism of claim 1, wherein: the support member is a wear member or an anti-wear member.

4. The impact mechanism of claim 1, wherein: the support member is a coating applied to the arm.

5. The impact mechanism of any one of claims 1 to 4, wherein: the impact mechanism comprises two gaskets which are respectively sleeved on the opposite end parts of the connecting pin and positioned in the space.

6. The impact mechanism of claim 5, wherein: the support members include two support members that fit over the connecting pins and are respectively located between the respective washers and the respective arm portions to space the respective washers and the respective arm portions apart.

7. The impact mechanism of claim 6, wherein: the support member includes an engagement portion for engaging to the arm portion.

8. The impact mechanism of claim 7, wherein: the joint has a clamping portion for clamping to the arm such that the support member is non-rotatably secured to the arm.

9. The impact mechanism of claim 5, wherein: the support member includes a single support member that is fitted over the connecting pin and is located between the washers and the arm portions, respectively, to space the respective washers and the respective arm portions apart.

10. The impact mechanism of claim 9, wherein: the single support member has a generally U-shaped cross-section in plan view such that the support member is non-rotatably secured to the arm.

11. The impact mechanism of any one of claims 1 to 3, wherein: the support member is non-rotatably fixed to the arm.

12. A hand-held power tool, comprising:

the impact mechanism of any one of claims 1-11;

a transmission mechanism; and

a drive mechanism operatively connected to the impact mechanism through the transmission mechanism.

13. An impact mechanism for a hand held power tool, characterized by: the method comprises the following steps:

a piston cylinder assembly having:

a piston cylinder including a connecting portion having opposing arms defining a space therebetween, the arms having a mounting portion;

a connecting pin mounted to the arm portion by the mounting portion and extending in the space, the connecting pin being adapted to connect with a transmission for connecting the piston cylinder assembly to a drive mechanism for reciprocating movement;

14. The impact mechanism of claim 13, wherein: the supporting component is a stamping part or a laser cutting part.

15. The impact mechanism of claim 13, wherein: the support member is a wear member or an anti-wear member.

16. The impact mechanism of claim 13, wherein: the support member is a coating applied to the arm.

17. The impact mechanism of any one of claims 13 to 15, wherein: the support member is non-rotatably fixed to the arm.