TW201819111A - Improved structure of pneumatic grinding machine which includes a motor body, a cylinder, a front cap, and a rear cap, in which an inlet passage is arranged on a right-hand side of the rear cap and a discharge passage is arranged on a left-hand side of the cylinder - Google Patents

Abstract

An improved structure of a pneumatic grinding machine includes a motor body, a cylinder, a front cap, and a rear cap, wherein the motor body is arranged in the cylinder and is positioned in a housing by the front cap and the rear cap. A rotary spindle extends from the motor body and is fixedly connected, through a left-handed thread, to a chuck assembly that is provided for clamping a grinding member. An intake passage is arranged in the rear cap and is extended to and in communication with the cylinder. A discharge passage is arranged in the cylinder and, in observation in a direction toward the grinding member, the inlet passage is arranged on a right-hand side of the rear cap and the discharge passage is arranged on a left-hand side of the cylinder so that airflow guided thereby drives the motor body to drive the rotary spindle to rotate in a counterclockwise direction to further drive the chuck assembly and the grinding member to rotate.

Description

Improved structure of pneumatic grinder

The present invention relates to a pneumatic grinder, and more particularly to a pneumatic grinder operated by hand.

Figures 7 and 8 show a conventional small handheld pneumatic grinder, which includes a rotating shaft 5, which is connected to a collet assembly 6 by a thread 51, and the collet assembly 6 is fastened to a clamp.磨 件 7。 Grinding piece 7. When using the pneumatic grinder, the operator holds it by hand and controls the introduction of high-pressure gas to drive the rotation shaft 5 to drive the collet assembly 6 and the grinding member 7 to rotate, and makes the grinding member 7 contact the workpiece for grinding. The artifact.

The above-mentioned thread 51 through which the rotating shaft 5 and the collet assembly 6 are connected are all designed as right-handed threads in accordance with the normal practice in the general mechanical structure. According to this, in order to cooperate with the right-hand thread 51 and prevent the rotation shaft 5 from being loosened with the collet assembly 6 when driven, the rotation direction of the rotation shaft 5 is from the rotation shaft 5 to the grinding member 7 From the perspective of the direction, it should be designed clockwise. However, a large number of sparks are emitted when the workpiece is ground. Because the rotating shaft 5 rotates clockwise, the sparks will be sprayed to the operator as shown in Figure 10, which will cause discomfort and even safety concerns.

For the confusion caused by the above-mentioned spark eruption direction, the operator has to change the posture of the hand-held pneumatic grinder so that the sparks are ejected in other directions; or change the position of himself where the ambient space allows, and face the workpiece sideways , Make the sparks blow out in other directions. Although these countermeasures can still continue to operate the grinder, due to the awkward posture of the handhold or the narrow operation space, the grinding action is very smooth, which affects the grinding results.

However, the foregoing problem is not merely solved by changing the direction in which the rotating shaft 5 drives the grinding member 7 to rotate. Specifically, the collet assembly 6 includes a collet holder 61, a collet 62, and a fixed cover 63. The collet 62 has a halved arc-shaped clamping block 621 with a gap between the clamping blocks 621. It is slightly open. The collet 62 is forcedly fixed in the collet holder 61 by the fixing cover 63, and the four clamping blocks 621 are forced to close to fasten a cylindrical abrasive piece 7, wherein the fixing The cap 63 is combined with the collet holder 61 by a right-handed thread 64. The problem is that if the direction in which the rotating shaft 5 drives the grinding member 7 is simply changed, the rotating shaft 5 will be loosened from the right-handed thread 51 of the collet assembly 6 during the rotation, and the fixing cover 63 will also The right-handed thread 64 on the collet holder 61 is loosened, so that the four-clamping block 621 of the collet 62 cannot press the grinding member 7 and cannot drive the grinding member 7 to rotate to grind the workpiece. Furthermore, if the four-piece collet 621 of the collet 62 is designed to be non-curved and have edges and corners in order to solve the above-mentioned problems, in order to push the grinding member 7 to rotate by the corners and corners, it must be matched with a grinding member of a corresponding shape. However, the spare parts of the abrasives on the market are all cylindrical, so this method will be difficult and difficult to improve.

The main object of the present invention is to provide a pneumatic grinding machine. The rotation shaft is viewed from the direction of the grinding part. The air inlet of the cylinder is provided on the right side and the air outlet is provided on the left side, thereby driving the rotation shaft to rotate counterclockwise. Sparks generated during grinding are sprayed away from the user; and the thread used for the shaft to lock the grinding parts is left-handed to avoid loosening during operation.

In order to achieve the foregoing object, the present invention provides an improved structure of a pneumatic grinder, which includes an air motor module having a motor body, a cylinder, a front cover, and a rear cover, wherein the motor body The front cover and the rear cover are provided in the cylinder, and the front cover and the rear cover are respectively provided on the front side and the rear side of the cylinder. The air motor module is positioned in a housing with the front cover and the rear cover; the motor body is extended A rotating shaft is fixedly connected to a collet assembly. The collet assembly is provided with a plurality of slightly opened clamping blocks for clamping an abrasive part. Each clamping block is provided with an oblique abutment surface and tightly abuts the collet assembly. The clamping blocks are further closed to fix the grinding piece; the air motor module is provided with an intake channel and an exhaust channel, thereby guiding the air flow to drive the motor body to drive the rotation shaft, and then the collet assembly and the The abrasive part rotates; it is characterized by: The rotating shaft and the collet assembly are fixedly connected by a first thread segment, wherein the first thread segment is a left-handed thread; the air inlet passage is provided on the rear cover and communicates with the cylinder, the Exhaust The channel is arranged on the cylinder, and viewed from the direction of the rotating shaft toward the grinding member, the intake channel is arranged on the right side of the rear cover, and the exhaust channel is arranged on the left side of the cylinder, so that the guided airflow drives the The shaft rotates counterclockwise.

In an embodiment, the collet assembly includes a collet base, a collet, and a fixed cover; the collet base is fixedly connected to the rotating shaft with the first thread segment, and the collet is embedded in the collet base. Inside, each clamping block is arranged on the collet; the fixing cover presses each clamping block and makes each oblique abutment surface abut against the collet seat, and then collapsing each clamping block to fix the abrasive part, and the fixing cover and The collet seat is fixedly connected by a second thread segment, wherein the second thread segment is a left-handed thread.

The above-mentioned objects and advantages of the present invention can be easily understood from the detailed description and accompanying drawings of selected embodiments below.

Please refer to FIGS. 1 and 2, which shows a first embodiment of the improved structure of the pneumatic grinder provided by the present invention, which has a housing 1 and an air motor module 2 inside. The air motor module 2 includes a motor body 21, a cylinder 22, a front cover 23, and a rear cover 24, wherein the front cover 23 and the rear cover 24 are respectively disposed on the front side and the rear side of the cylinder 22, and respectively Abut against the wall surface inside the casing 1, thereby positioning the cylinder 22. The above-mentioned cylinder 22 extends a positioning pin 221 on one side facing the front cover and the rear cover, respectively, 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 rotation shaft 25 protrudes outward from the cylinder 22. The motor body 21 can drive the rotation shaft 25 to rotate.

On the bearing, the rotating shaft 25 is fixedly connected to a collet assembly 3 for clamping a grinding member 4, and the grinding member 4 is driven by the rotation of the rotating shaft 25 for grinding the workpiece. In this embodiment, the collet assembly 3 includes a collet base 31, a collet 32, and a fixed cover 33. One end of the collet base 31 is provided with a screw hole 311. A thread section 312 is screwed, and here the first thread section 312 is a left-hand thread. The other end of the collet base 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 clamping blocks 321, and a grinding member 4 can be accommodated between each clamping block 321. Each clamping block 321 has some flexibility and can be abutted against each other after being stressed. The fixing cover 33 is locked outside the accommodation hole 313 of the collet base 31 with a second thread section 331, thereby suppressing the collet 32 to be embedded in the accommodation hole 313; each clamping block 321 is provided There is an oblique abutment surface 322, and each clamping block 321 is pressed by the fixing cover 33, and the oblique abutment surface 322 abuts against the edge of the accommodation hole 313, and then abuts against each other to clamp the abrasive member 4. The second thread segment 331 is further defined as 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 the airflow in 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 this embodiment, the intake passage 26 is provided in the rear cover 24 and communicates with the cylinder 22, and the exhaust passage 27 is provided in the cylinder 22, with the rotating shaft 25 toward the abrasive member (as shown in the figure) In the direction of the arrow shown), the intake passage 26 is provided to the right of the rear cover 24, and the exhaust passage 27 is provided to the left of the cylinder 22. According to this, the high-pressure gas enters the right side of the cylinder 22 from the intake passage 26 and flows to the left in a counterclockwise direction and is discharged from the exhaust passage 27. Therefore, the motor body 21 is driven to rotate in a counterclockwise direction, thereby driving The rotating shaft 25 is rotated in a counterclockwise direction, so that the collet assembly 3 and the grinding member 4 are also rotated in a counterclockwise direction simultaneously.

With the configuration of the above structure and the mechanical design of the rotation of the rotating shaft, when the present invention is used, as shown in FIG. 4, because the grinding member 4 rotates in a counterclockwise direction (viewed by the rotating shaft toward the grinding member 4), The sparks generated by the grinding are sprayed away from the operator to avoid injury to the operator. In addition, corresponding to the rotation direction of the rotating shaft, the first threaded section connected between the collet assembly and the rotating shaft, and the second threaded section of the fixing cover on the collet assembly and the collet seat are all left-handed. The spiral connection relationship can be prevented from being loosened during 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 rotation direction of the motor body. In other words, in the conventional structure, as shown in FIG. 9, the rotating shaft 5 is in the direction of the abrasive member ( In the direction of the arrow as shown in the figure) In view, the intake passage 811 is provided to the left of the rear cover 81, and the exhaust passage 822 is provided to the right of the cylinder 82, so that high-pressure gas can enter the cylinder 82 from the intake passage 811. To the left, and flows to the right in a clockwise direction and is discharged from the exhaust passage 822, thereby driving the motor body 83 to drive the rear-side grinding member 7 to rotate in a clockwise direction. The cylinder 22 of the present invention (refer to the one shown in FIG. 3) is a cylinder 82 with a conventional structure, which can be reversed 180 degrees forward and backward to change the position of the exhaust passage 822 to the left. The cylinder 22 of the invention, therefore, the cylinder 22 of the invention can be completed without excessive design and manufacturing costs.

In addition, as shown in FIG. 9, the positioning pin 822 of the cylinder 82 of the conventional structure is provided on the right side of the cylinder 82, and after being reversed and used as the cylinder of the present invention, the positioning pin will be converted to the left of the cylinder According to this, the front cover 23 of the present invention is provided with a left pin hole 231 on the left corresponding position as shown in FIG. 3 for the positioning pin 221 of the cylinder 22 to be inserted and positioned. Furthermore, the front cover 23 of the present invention is provided with a right pin hole 232 on the right side, wherein the right pin hole 232 is left-right symmetrical with the left pin hole 231, but the right pin hole 232 follows the conventional structure front cover 84. The right pin hole 841 comes from the right side; in other words, because the cover 84 has a right pin hole 841 on the right side of the front cover, it is only necessary to provide an additional left pin hole on the left side of the front cover 84. It can be used as the front cover 23 of the present invention. On the other hand, such a front cover with left and right pin holes can further provide the present invention and the use of a conventional structure, and can effectively reduce the overall cost.

Figures 5 and 6 show the second embodiment of the present invention; this embodiment is based on the aforementioned first embodiment, and is a structural change of the collet assembly. In this embodiment, a recessed hole 251 is recessed at the end of the rotating shaft 25, and the collet assembly 3 is provided with only the collet 32. The collet 32 and the recessed hole 251 are mutually connected by the first thread section 312. And the first thread section 312 is a left-handed thread, so that the collet 32 is fixedly connected to the rotating shaft 25. Further, as the collet 32 is locked into the insertion hole 251, each clamping block 321 of the collet 32 is pressed against the edge of the insertion hole 251 with its oblique abutment surface 322, so that the clamping blocks 321 lean against each other. Combined to clamp the abrasive part 4. According to this, in addition to this embodiment, the rotating shaft 25 can also be used to drive the collet 32 and the grinding member 4 to rotate in a counterclockwise direction (viewed by the rotating shaft 25 toward the grinding member 4), so as to make the spark toward In addition to the effect of spraying away from the operator, the left-hand thread of the collet 32 and the insertion hole 251 of the rotating shaft 25 is used to prevent the collet 32 from loosening during the rotation, and it can be used normally.

However, the disclosure of the above embodiments is only used to illustrate the present invention and is not intended to limit the present invention. Therefore, the replacement of equivalent components should still belong to the scope of the present invention.

In summary, those skilled in the art can understand that the present invention can indeed achieve the aforementioned purpose, and it has indeed complied with the provisions of the Patent Law, and filed an application in accordance with the law.

‧‧‧Shell

2‧‧‧Air Motor Module

21‧‧‧Motor body

2111‧‧‧blades

22‧‧‧cylinder

221‧‧‧Positioning Pin

23‧‧‧ front cover

233‧‧‧Left pin hole

232‧‧‧right pin hole

24‧‧‧ back cover

25‧‧‧ shaft

251‧‧‧Embedded

26‧‧‧Air inlet channel

27‧‧‧Exhaust channel

‧‧‧ collet assembly

31 · ‧‧ collet seat

311‧‧‧Screw holes

312‧‧‧First thread section

313‧‧‧Receiving hole

32‧‧‧ collets

321‧‧‧Clamp

322‧‧‧inclined

33‧‧‧Fixed cover

331‧‧‧Second thread section

4‧‧‧ Abrasive parts

5‧‧‧ shaft

51 · ‧‧Thread

6‧‧‧ Collet Assembly

61 · ‧‧ collet holder

62‧‧‧ collets

621‧‧‧ Clamping block

63‧‧‧Fixed cover

64‧‧‧ Right-hand thread

7‧‧‧ Abrasives

81 · ‧‧ back cover

811‧‧‧Air inlet channel

82‧‧‧cylinder

827‧‧‧Exhaust channel

822‧‧‧Positioning Pin

83‧‧‧Motor body

84‧‧‧ front cover

841‧‧‧right pin hole

Fig. 1 is a schematic exploded perspective view of the first embodiment of the present invention; Fig. 2 is a schematic longitudinal sectional view of the first embodiment of the present invention; Fig. 3 is an exploded schematic view of the pneumatic motor module of the first embodiment of the present invention; Figure 5 is a schematic view of the first embodiment of the present invention; Figure 5 is a schematic three-dimensional exploded view of the second embodiment of the present invention; Figure 6 is a schematic longitudinal sectional view of the second embodiment of the present invention; Figure 7 is a conventional structure A three-dimensional exploded schematic diagram; FIG. 8 is a longitudinal sectional schematic diagram of a conventional structure; FIG. 9 is an exploded schematic diagram of a conventional structure air motor module; and FIG. 10 is a schematic diagram of a used state of the conventional structure.

Claims (4)

An improved structure of a pneumatic grinder includes an air 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. The air motor module is positioned in a housing with the front cover and the rear cover; the motor body extends a rotating shaft, and the rotating shaft is fixedly connected to a cylinder. The collet assembly is provided with a plurality of slightly opened clamping blocks for clamping commonly used abrasive parts on the market. Each clamping block is provided with an oblique abutting surface and tightly abuts the collet assembly, so that each clamping block is closed. The grinding piece is fixed; the air motor module is provided with an intake passage and an exhaust passage, thereby guiding the air flow to drive the motor body to drive the rotation shaft, and then the collet assembly and the grinding piece to rotate; : The rotating shaft and the collet assembly are fixedly connected by a first thread segment, wherein the first thread segment is a left-handed thread; the intake passage is provided on the rear cover and communicates with the cylinder, and the exhaust passage is provided on the cylinder To Viewing from the direction of the rotating shaft to the grinding member, the air inlet passage is provided to the right of the rear cover, and the exhaust passage is provided to the left of the cylinder, so that the guided airflow drives the shaft to rotate counterclockwise. The improved structure of the pneumatic grinder according to claim 1, wherein the collet assembly includes a collet base, a collet and a fixed cover; the collet base is fixedly connected with the rotating shaft by the first thread segment, The collet is embedded in the collet holder, wherein each clip block is provided on the collet; the fixed cover presses each clip block and makes each oblique abutment surface abut against the collet holder, and then closes each clip block to The abrasive part is fixed, and the fixing cover and the collet base are fixedly connected by a second thread segment, wherein the second thread segment is a left-handed thread. The improved structure of the pneumatic grinder according to claim 1, wherein the collet assembly includes a collet; the shaft is recessed with an embedded hole, and the collet and the embedded hole are fixedly connected 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 a positioning pin is provided on one side of the cylinder facing the front cover, and the cylinder uses the positioning The pin is inserted into one of the pin holes and is positioned with the front cover.