TWI611869B - Improved structure of pneumatic grinding machine - Google Patents

Description

Improved structure of pneumatic grinding machine

The invention relates to a pneumatic grinder, and more particularly to a pneumatic grinder that operates in a hand-held manner.

Figures 7 and 8 show a conventional small hand-held pneumatic grinder comprising a rotating shaft 5 which is connected by a thread 51 to a collet assembly 6, and the collet assembly 6 is securely clamped Abrasive member 7. When the pneumatic grinder is used, the operator holds the hand and controls the introduction of the high-pressure gas to drive the rotating shaft 5 to rotate, thereby driving the collet assembly 6 and the grinding member 7 to rotate, and the grinding member 7 is in contact with the workpiece for grinding. The workpiece.

The aforementioned thread 51 connected between the rotating shaft 5 and the collet assembly 6 is designed to be a right-handed thread according to the usual practice of the general mechanical structure. Accordingly, in order to cooperate with the right-hand thread 51 and prevent the shaft 5 from being loosened when the shaft 5 is driven to rotate, the rotation direction of the shaft 5 is from the shaft 5 toward the grinding member 7. The direction of the direction should be designed to be clockwise. However, when the workpiece is ground, a large amount of sparks are ejected. Since the shaft 5 is rotated in a clockwise direction, the spark will be sprayed toward the operator as shown in Fig. 10, which causes discomfort and even safety concerns.

For the trouble caused by the above-mentioned spark ejecting direction, the operator has to change the posture of the hand-held pneumatic grinder to cause the spark to be ejected in other directions; or change the position of the self in the environment, and face the workpiece sideways. , so that the spark is sprayed in other directions. Although these methods can continue to operate the grinder, the posture of the hand is awkward, or the operation space is narrow, which causes the grinding action to be very unsmooth, thereby affecting the results of the grinding.

However, the foregoing problem can be solved not only by changing the direction in which the rotating shaft 5 rotates the grinding member 7. In detail, the collet assembly 6 includes a collet holder 61, a collet 62, and a fixed cover 63. The collet 62 has a quarter-shaped arcuate clip 621 with a gap between the clips 621. The collet 62 is tightly fixed in the collet holder 61 by the fixing cover 63, and the four clamping blocks 621 are forced to be fastened to fasten a cylindrical abrasive member 7, wherein the collet is fixed. The lid 63 and the collet holder 61 are coupled by a right-handed thread 64. The problem is that if only the direction of rotation of the grinding member 7 is changed by the rotating shaft 5, the rotating shaft 5 will be released from the right-hand thread 51 of the collet assembly 6 during the rotation, and the fixing cover 63 will also be self-contained. The right-handed thread 64 on the collet 61 is loosened, thereby causing the four clamps 621 of the collet 62 to be unable to tighten the abrasive member 7, thereby preventing the abrasive member 7 from rotating to grind the workpiece. Furthermore, if the four clips 621 of the collet 62 are designed to be non-arc and have an angular shape in order to solve the above problem, in order to push the grinding member 7 to rotate by the angular direction, it is necessary to match the grinding member with the corresponding shape. However, the grinding parts on the market are all cylindrical, so this method will hinder the difficulty and improve the effect.

The main object of the present invention is to provide a pneumatic grinding machine, wherein the rotating shaft is viewed from the direction of the grinding member, the air inlet of the cylinder is disposed on the right side, and the air outlet is disposed on the left side, thereby driving the rotating shaft to rotate counterclockwise, thereby The spark generated during grinding is ejected away from the user; and the thread used to lock the grinding member is left-handed to avoid loosening during operation.

For the purpose of the foregoing, the present invention provides an improved structure of a pneumatic grinder comprising a pneumatic motor module having a motor body, a cylinder, a front cover and a rear cover, wherein the motor body Provided in the cylinder, the front cover and the rear cover are respectively disposed on the front side and the rear side of the cylinder, and the air motor module is positioned in a casing by the front cover and the rear cover; the motor body extends a rotating shaft fixedly connected to a collet assembly, wherein the collet assembly is provided with a plurality of slightly open-shaped clamping blocks for clamping an abrasive member, each clamping block is provided with a diagonal abutting surface and abuts against the collet assembly. And clamping the clips to fix the grinding member; the air motor module is provided with an air inlet passage and an exhaust passage, thereby guiding the airflow to drive the motor body to drive the rotating shaft to rotate, and thereby driving the collet assembly and the The grinding member rotates; the rotating shaft is fixedly coupled to the collet assembly by a first thread segment, wherein the first thread segment is a left-hand thread; the air inlet passage is disposed at the rear cover and communicates with the cylinder, Exhaust air The passage is disposed in the cylinder, and the rotating shaft is viewed in the direction of the grinding member, the intake passage is disposed at a right side of the rear cover, and the exhaust passage is disposed at a left side of the cylinder, so that the guided airflow drives the The shaft rotates in a counterclockwise direction.

In one embodiment, the collet assembly includes a collet holder, a collet, and a fixing cover; the collet holder is fixedly coupled to the rotating shaft by the first threaded portion, and the collet is embedded in the collet holder Inside, wherein each of the clamping blocks is disposed on the collet; the fixing cover presses each of the clamping blocks and abuts each of the inclined abutting faces against the collet holder, thereby retracting the clamping blocks to fix the grinding member, and the fixing cover is The collet holder is fixedly coupled by a second threaded section, wherein the second threaded section is a left-handed thread.

The above objects and advantages of the present invention will be readily understood from the following detailed description of the embodiments of the invention.

Referring to Figures 1 and 2, there is shown a first embodiment of the improved structure of the pneumatic grinder provided by the present invention having a housing 1 with a pneumatic motor module 2 disposed therein. The air motor module 2 includes a motor body 21, a cylinder 22, a front cover 23 and a rear cover 24. The front cover 23 and the rear cover 24 are respectively disposed on the front side and the rear side of the cylinder 22, respectively. The wall 22 is positioned against the interior of the housing 1 thereby positioning the cylinder 22. The cylinder 22 extends a positioning pin 221 on one side of the front cover and the rear cover, and thereby positions the front cover 23 and the rear cover 24 with each other. The motor body 21 and a plurality of blades 211 radially disposed on the motor body 21 are disposed in the cylinder 22, and a rotating shaft 25 is protruded outwardly of the cylinder 22, and the motor body 21 can drive the rotating shaft 25 to rotate.

The rotating shaft 25 is fixedly connected to a collet assembly 3 for clamping an abrasive member 4, and the grinding member 4 is driven by the rotation of the rotating shaft 25 to grind the workpiece. In the embodiment, the collet assembly 3 includes a collet holder 31, a collet 32, and a fixing cover 33. One end of the collet holder 31 is provided with a screw hole 311, and the rotating shaft 25 is A threaded section 312 is threaded, where the first threaded section 312 is a left-handed thread. The other end of the collet holder 31 is provided with a receiving hole 313 for the collet 32 to be embedded therein. The collet 32 is provided with a plurality of slightly open clips 321 , and an abrasive member 4 is accommodated between each of the clips 321 . Each of the clips 321 has a slight flexibility and can abut against each other after being stressed. The fixing cover 33 is locked to the receiving hole 313 of the collet holder 31 by a second thread segment 331, thereby pressing the collet 32 to fit in the receiving hole 313; each clamping block 321 is provided There is a slanting abutment surface 322, and each of the clamping blocks 321 is pressed by the fixing cover 33 to abut the edge of the accommodating hole 313 with the slanting abutting surface 322, thereby abutting against each other to clamp the grinding member 4. It is further defined that the second thread segment 331 is a left-handed thread.

On the other hand, as shown in FIG. 3, the air motor module 2 is provided with an intake passage 26 and an exhaust passage 27 for guiding airflow into and out of the cylinder 22, thereby driving the motor body 21 to rotate, thereby driving The rotating shaft 25 rotates and synchronously drives the collet assembly 3 and the grinding member 4 to rotate for grinding the workpiece. In the present embodiment, the intake passage 26 is disposed in the rear cover 24 and communicates with the cylinder 22, and the exhaust passage 27 is disposed in the cylinder 22 with the rotating shaft 25 facing the grinding member (as shown in the figure) In the direction of the arrow, the intake passage 26 is disposed to the right of the rear cover 24, and the exhaust passage 27 is disposed to the left of the cylinder 22. Accordingly, the high-pressure gas enters the right side of the cylinder 22 from the intake passage 26, and flows to the left in the counterclockwise direction to be discharged from the exhaust passage 27, thereby driving the motor body 21 to rotate in the counterclockwise direction, thereby driving The rotating shaft 25 is rotated in a counterclockwise direction to rotate the collet assembly 3 and the grinding member 4 in a counterclockwise direction.

According to the configuration of the above structure and the mechanical design of the steering of the shaft, the invention is used in the counterclockwise direction (in the direction of the grinding member 4 in the direction of the grinding member 4) as shown in FIG. The spark generated by the grinding is sprayed away from the operator to avoid operator injury. In addition, corresponding to the rotation direction of the rotating shaft, the first thread segment connected between the collet assembly and the rotating shaft, and the fixing screw on the collet assembly and the second thread segment on the collet holder adopt a left-hand thread. The above spiral connection relationship can be prevented from being loosened during the rotation.

On the other hand, one of the differences between the present invention and the conventional structure is that the high pressure gas drives the direction of rotation of the motor body, in other words, in the conventional structure, as shown in Fig. 9, the direction of the rotating shaft 5 is toward the grinding member ( As shown in the direction of the arrow in the figure, the intake passage 811 is provided to the left of the rear cover 81, and the exhaust passage 821 is provided to the right of the cylinder 82, so that high-pressure gas can enter the cylinder 82 from the intake passage 811. The left side flows to the right in the clockwise direction and is discharged from the exhaust passage 821, whereby the motor body 83 is driven to drive the grinding member 7 at the rear end to rotate in the clockwise direction. Further, the cylinder 22 of the present invention (refer to FIG. 3) can be rotated by 180 degrees from the cylinder 82 of the conventional structure, and the position of the exhaust passage 821 can be changed to the left. The cylinder 22 of the invention is such that the cylinder 22 of the present invention can be completed without excessive design and manufacturing costs.

Further, as shown in Fig. 9, the positioning pin 822 of the cylinder 82 of the prior art is disposed on the right side of the cylinder 82, and after being reversed and used as the cylinder of the present invention, the positioning pin is switched to the left of the cylinder. Accordingly, the front cover 23 of the present invention is provided with a left pin hole 231 at the corresponding position on the left side as shown in FIG. 3 for the positioning pin 221 of the cylinder 22 to be inserted and positioned. Further, the front cover 23 of the present invention is further provided with a right pin hole 232 on the right side, wherein the right pin hole 232 is bilaterally symmetrical with the left pin hole 231, but the right pin hole 232 is connected to the front cover 84 by a conventional structure. The right pin hole 841 comes from the right side; in other words, since the front cover 84 has a right pin hole 841 disposed on the right side thereof, it is only necessary to provide a left pin hole on the left side of the conventional front cover 84. It can be used as the front cover 23 of the present invention. On the other hand, the front cover having the left and right pin holes can provide the present invention and the conventional structure, and can effectively reduce the overall cost.

The figures shown in Figures 5 and 6 are the second embodiment of the present invention; this embodiment is based on the first embodiment described above, and is a structural change of the collet assembly. In the embodiment, the end of the rotating shaft 25 is recessed with a through hole 251, and the collet assembly 3 is only provided with the collet 32. The collet 32 and the through hole 251 are mutually coupled with the first thread segment 312. The first thread segment 312 is screwed, whereby the collet 32 is fixedly coupled to the rotating shaft 25. Further, as the collet 32 locks into the through hole 251, the clips 321 of the collet 32 are further abutted against the edge of the through hole 251 by the slanting surface 322, so that the clips 321 are placed against each other. The abrasive member 4 can be clamped. Accordingly, in this embodiment, the rotating shaft 25 is driven to rotate the collet 32 and the grinding member 4 in the counterclockwise direction (the direction of the rotating shaft 25 toward the grinding member 4), thereby causing the spark to In addition to the effect of being sprayed away from the direction of the operator, the left-handed thread of the collet 32 and the fitting hole 251 of the rotating shaft 25 prevents the collet 32 from being loosened during the rotation, and can be used normally.

However, the above description of the embodiments is merely illustrative of the invention and is not intended to limit the invention, and the replacement of equivalent elements is still within the scope of the invention.

In summary, it will be apparent to those skilled in the art that the present invention can achieve the foregoing objectives and is in accordance with the provisions of the Patent Law.

1‧‧‧shell

2‧‧‧Air motor module

21‧‧‧Motor body

211‧‧‧ leaves

22‧‧‧ cylinder

221‧‧‧Locating pin

23‧‧‧ front cover

231‧‧‧Left pin hole

232‧‧‧right pin hole

24‧‧‧ Back cover

25‧‧‧ shaft

251‧‧‧ hole

26‧‧‧Intake passage

27‧‧‧Exhaust passage

3‧‧‧ Collet assembly

31‧‧‧Clamp holder

311‧‧‧ screw hole

312‧‧‧First thread segment

313‧‧‧ accommodating holes

32‧‧‧Clamp

321‧‧‧Clamp

322‧‧‧ obliquely

33‧‧‧Fixed cover

331‧‧‧Second thread segment

4‧‧‧Abrased parts

5‧‧‧ shaft

51‧‧‧ thread

6‧‧‧ Collet assembly

61‧‧‧Clamp holder

62‧‧‧ Collet

621‧‧‧Clamp

63‧‧‧Fixed cover

64‧‧‧Right thread

7‧‧‧Abrased parts

81‧‧‧Back cover

811‧‧‧Intake passage

82‧‧‧ cylinder

821‧‧‧Exhaust passage

822‧‧‧Locating pin

83‧‧‧Motor body

84‧‧‧ front cover

841‧‧‧right pin hole

1 is a perspective exploded view of a first embodiment of the present invention; FIG. 2 is a longitudinal cross-sectional view of a first embodiment of the present invention; and FIG. 3 is an exploded perspective view of a pneumatic motor module according to a first embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 5 is a perspective exploded view of a second embodiment of the present invention; FIG. 6 is a schematic longitudinal cross-sectional view of a second embodiment of the present invention; FIG. 8 is a schematic longitudinal sectional view of a conventional structure; FIG. 9 is an exploded perspective view of a conventional structure air motor module; FIG. 10 is a schematic view showing a state of use of the conventional structure.

1‧‧‧shell

2‧‧‧Air motor module

21‧‧‧Motor body

211‧‧‧ leaves

22‧‧‧ cylinder

221‧‧‧Locating pin

23‧‧‧ front cover

24‧‧‧ Back cover

25‧‧‧ shaft

26‧‧‧Intake passage

27‧‧‧Exhaust passage

3‧‧‧ Collet assembly

31‧‧‧Clamp holder

311‧‧‧ screw hole

312‧‧‧First thread segment

313‧‧‧ accommodating holes

32‧‧‧Clamp

321‧‧‧Clamp

322‧‧‧ obliquely

33‧‧‧Fixed cover

331‧‧‧Second thread segment

4‧‧‧Abrased parts

Claims (4)

An improved structure of a pneumatic grinder includes a pneumatic motor module having a motor body, a cylinder, a front cover and a rear cover, wherein the motor body is disposed in the cylinder, and the front The cover and the rear cover are respectively disposed on the front side and the rear side of the cylinder, and the air motor module is positioned in a casing by the front cover and the rear cover; the motor body extends out of a rotating shaft, and the rotating shaft is fixedly connected to a cylinder a clip assembly, wherein the collet assembly is provided with a plurality of slightly open clips for clamping the common abrasive parts of the market, each of the clips is provided with a slanting abutting surface and abutting the collet assembly, thereby folding the clips Blocking the fixed grinding member; the air motor module is provided with an intake passage and an exhaust passage, thereby guiding the airflow to drive the motor body to drive the rotating shaft to rotate, and thereby driving the collet assembly and the grinding member to rotate; The shaft is fixedly connected to the collet assembly by a first thread segment, wherein the first thread segment is a left-hand thread; the air inlet passage is disposed at the rear cover and communicates with the cylinder, and the exhaust passage is disposed at the cylinder The cylinder to the Views of the axis of the grinding member in the direction of the intake passage provided in the rear of the right, left disposed in the exhaust passage of the cylinder, so that the guided gas flow driving the shaft is rotated in the counterclockwise direction. The improved structure of the pneumatic grinder according to claim 1, wherein the collet assembly comprises a collet holder, a collet and a fixing cover; the collet holder and the rotating shaft are fixedly connected by the first thread segment, The collet is embedded in the collet holder, wherein each of the clips is disposed on the collet; the fixing cap presses each of the clips and the respective reclining surfaces abut against the collet holder, thereby collapsing each The clamping block fixes the grinding member, and the fixing cover is fixedly connected with the collet holder by a second thread segment, wherein the second thread segment is a left-handed thread. The improved structure of the pneumatic grinder as claimed in claim 1, wherein the collet assembly comprises a collet; the rotating shaft is recessed with an insertion hole, and the collet is fixedly connected with the insertion hole by the first thread segment. The improved structure of the pneumatic grinder according to claim 1, wherein the front cover is provided with two left and right symmetrical pin holes, and the cylinder is provided with a positioning pin facing one side of the front cover, and the cylinder is positioned by the cylinder The pin is inserted into one of the pin holes to be positioned with the front cover.