Patent Application
20220161386
The disclosure relates to a pneumatic device, and more particularly to a pneumatic device for removing rust, scale or undesirable material on a work surface.
Referring to
However, when such conventional pneumatic rust removing gun is in use, the repetitive striking movements of the piston 93 and the impact block 95 usually result in generation of strong vibration that can cause discomfort to a user. In order to reduce the vibration, the conventional pneumatic rust removing gun is provided with a rubber pad (not shown) for shock absorption, the effect of which, however, is rather limited.
Therefore, the object of the disclosure is to provide a pneumatic device that can alleviate the drawback of the prior art.
According to the disclosure, a pneumatic device is adapted to be connected to an air supply device. The pneumatic device includes a casing unit, a cylinder, a hollow piston rod, an impact unit and a resilient member.
The casing unit surrounds an axis, defines a first chamber, a receiving space and a front space that are arranged along the axis, and has an air inlet that is adapted to allow entry of air from the air supply device. The receiving space is disposed between and in spatial communication with the first chamber and the front space.
The cylinder is movably received in the receiving space, and has a surrounding wall, a partition wall, an air passage unit and an annular groove. The surrounding wall surrounds the axis. The partition wall extends in a direction transverse to the axis, and is surrounded by and connected to the surrounding wall such that the partition wall divides an inner space of the surrounding wall into a second chamber opened towards the first chamber, and a releasing room opened towards the front space. The air passage unit is formed in the surrounding wail. The annular groove is indented from an inner surface of the surrounding wall, and is disposed about the axis.
The hollow piston rod movably extends from the first chamber into the second chamber, and is in sliding engagement with the inner surface of the surrounding wall. The piston rod has an inlet channel, a communicating room and an air hole unit. The inlet channel extends along the axis and is in spatial communication with the first chamber. The communicating room is separated from the inlet channel, and is in spatial communication with the second chamber. The air hole unit is in spatial communication with the inlet channel and the communicating room.
The impact unit is detachably mounted in the releasing room of the cylinder and has an impact portion that is exposed outwardly from the casing unit. The resilient member is disposed in the front space and is connected resiliently between the casing unit and the impact member for pushing the impact unit towards the piston rod.
The cylinder and the piston rod are movable reciprocally relative to each other along the axis to change between a pneumatic state, where the air hole unit spatially communicates the inlet channel with the annular groove, and spatially communicates the annular groove with the communicating room and the second chamber, such that the air is allowed to travel from the inlet channel into the second chamber, so as to move the impact portion of the impact unit away from the casing unit, and an air discharging state, where the air passage unit spatially communicates the second chamber with the receiving space, and spatially communicates the receiving space with the releasing room, such that the air is allowed to travel from the second chamber into the releasing room and to be discharged out of the casing unit, so as to move the impact portion of the impact unit towards the casing unit by restoring action of the resilient member.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, of which:
Before the present disclosure is described in greater detail, it should be noted that where considered appropriate, reference numerals or terminal portions of reference numerals have been repeated among the figures to indicate corresponding or analogous elements, may optionally have similar characteristics.
Referring to
The casing unit 1 surrounds an axis (X), defines a first chamber 101, a receiving space 100 and a front space 102 that are arranged along the axis (X), and has an air inlet 114 that is adapted to allow entry of the compressed air from the air supply device 8. The receiving space 100 is disposed between and in spatial communication with the first chamber 101 and the front space 102.
In the present embodiment, the casing unit 1 includes a handheld member 11, a main tube member 12, a front tube member 13, a first gasket 14 and a second gasket 15.
The main tube member 12 is threadedly and detachably connected to the handheld member 11. The front tube member 13 is threadedly and detachably connected to the main tube member 12. The first gasket 14 is an O-ring, and is disposed between the handheld member 11 and the main tube member 12 so as to establish an airtight seal therebetween. The second gasket 15 is an O-ring, and is disposed between the main tube member 12 and the front tube member 13 so as to establish an airtight seal therebetween.
Specifically, referring to
The cover component 112 is disposed between the first chamber 101 and the receiving space 100, is formed with a through hole 1120, and has a main cover 116, an inner airtight ring 117, an outer airtight ring 118 and a retaining ring 119.
The main cover 116 is formed with the through hole 1120. The inner airtight ring 117 surrounds the through hole 1120, and is connected between the main cover 116 and the piston rod 4 so as to establish an air tight seal therebetween. The outer airtight ring 118 surrounds the main cover 116, and is connected between the main cover 116 and the hollow body 111 so as to establish an air tight seal therebetween. The retaining ring 119 is partially embedded in an inner surface of the hollow body 111 and abuts against a bottom end of the main cover 116 for maintaining position of the main cover 116. It should be noted that, in the present embodiment, the inner and outer airtight rings 117, 118 are O-rings that are embedded in the main cover 116, and the retaining ring 119 is a C-type retaining ring (i.e., snap ring or C-clip), but they are not limited thereto.
The main tube member 12 of the casing unit 1 is hollow, has opposite open ends, surrounds the axis (X) and defines the receiving space 100. The main tube member 12 is formed with an internal thread 121 threadedly engaged with the external thread 113 of the handheld member 11, and an external thread 122 opposite to the internal thread 121 along a direction of the axis (X).
The front tube member 13 of the casing unit 1 is hollow, has opposite open ends, surrounds the axis (X) and defines the front space 102. The front tube member 13 has a mounting portion 131, a housing portion 133 and a stopping portion 134 that are arranged along the axis (X). The mounting portion 131 is formed with an internal thread threadedly engaged with the external thread 122 of the main tube member 12. The housing portion 133 defines a stepped inner surface. The main tube member 12 abuts against a shoulder section of the stepped inner surface defined by the housing portion 133.
The operating unit 2 includes a valve assembly 21 and a pressing member 22. The valve assembly 21 includes an air valve 211, a plug piece 212, a conical spring 213 and two third gaskets 214.
The air valve 211 is disposed in the valve opening 115 of the handheld member 11, and is movable to permit or prevent spatial communication between the air inlet 114 and the first chamber 101 (see
The pressing member 22 is mounted to the handheld member 11, and is operable to move the air valve 211. Specifically, the pressing member 22 is pivoted to the handheld member 11 for movably abutting against an end portion of the air valve 211 that protrudes from the handheld unit 11 (see
Referring to
The surrounding wall 31 surrounds the axis (X). The partition wall 32 extends in a direction substantially perpendicular to the axis (X), and is surrounded by and connected to the surrounding wall 31 such that the partition wall 32 divides an inner space of the surrounding wall 31 into a second chamber 103 opened towards the first chamber 101, and a releasing room 104 opened towards the front space 102.
The air passage unit 310 is formed in the surrounding wall 31, and includes at least one first passage 312 and at least one second passage 313 that are formed through the surrounding wall 31. The at least one second passage 313 spatially communicates the receiving space 100 with the releasing room 104.
It should be noted that, in the present embodiment, the air passage unit 310 includes four first passages 312 and six second passages 313. The diameter of the second passages 313 is smaller than that of the first passages 312. The first passages 312 are angularly spaced apart from each other with respect to the axis (X). The second passages 313 are also angularly spaced apart from each other with respect to the axis (X). However, numbers and configurations of the first and second passages 312, 313 are not limited to the present embodiment.
The annular groove 311 is indented from an inner surface of the surrounding wall 31, and is disposed about the axis (X). The distance between the annular groove 311 and the releasing room 104 is greater than the distance between the at least one first passage 312 and the releasing room 104.
Referring to
The piston rod 4 further has an channel 43, a communicating room 44 and an air hole unit 40.
The inlet channel 43 extends through the first segment 41, along the axis (X), into the second segment 42, and is in spatial communication with the first chamber 101. The communicating room 44 is formed in the second segment 42, is separated from the inlet channel 43, and is in spatial communication with the second chamber 103.
The air hole unit 40 is in spatial communication with the inlet channel 43 and the communicating room 44, and includes at least one first hole 45, at least one second hole 46 and at least one third hole 47.
Referring specifically to
It should be noted that, in the present embodiment, the air hole unit 40 includes two first holes 45, two second holes 46 and two third holes 47. The first and second holes 45, 46 extend radially with respect to the axis (X), and are angularly spaced apart from each other. The third holes 47 extend in a direction of axis (X) and are disposed at opposite sides of the axis (X). However, numbers and configurations of the first, second and third holes 45, 46, 47 are not limited to the present embodiment.
Referring again to
The resilient member 6 is disposed in the front space 102 of the casing unit 1, and is connected resiliently between the casing unit 1 and the impact member 5 for pushing the impact unit 5 towards the piston rod 4. In the present embodiment, the resilient member 6 is a coiled compression spring extending along the axis (X), and has opposite ends abutting respectively against the needle seat 51 and the stopping portion 134 of the front tube member 13 of the casing unit 1.
Referring to
When the cylinder 3 and the piston rod 4 are in the pneumatic state, the air hole unit 40 spatially communicates the inlet channel 43 with the annular groove 311 and the annular groove with the communicating room 44 and spatially communicates the second chamber 103, such that the air is allowed to travel from the inlet channel 43 into the second chamber 103, so as to move the impact portion 521 of the impact unit 5 away from the casing unit 1.
When the cylinder 3 and the piston rod 4 are in the air discharging state, the air passage 310 spatially communicates the second chamber 103 with the receiving space 100, and the receiving space 100 with the releasing room 104, such that the air is allowed to travel from the second chamber 103 into the releasing room 104 and to be discharged out of the casing unit 1, so as to move the impact portion 521 of the impact unit 5 towards the casing unit 1 by restoring action of the resilient member 6.
Specifically, prior to the operation, the pressing member 22 is not pressed (see
To start the operation, the pressing member 22 is pressed toward the casing unit 1, allowing the compressed air (I) to travel from the air inlet 114 into the first chamber 101 and the inlet channel 43. During this period of time, the piston rod 4 is forced by the compressed air (I) towards the releasing room 104.
Once the cylinder 3 and the piston rod 4 come into the pneumatic state (see
It should be noted that, when the cylinder 3 and the piston rod 4 come into the air discharging state (see
Through repetition of the abovementioned process, the impact portion 521 is able to remove rust, scale or undesirable material from the work surface.
Referring to
Referring to
In sum, in virtue of configurations of the air passage unit 310 of the cylinder 3 and the air hole unit 40 of the piston rod 4 and disposition first and second chambers 101, 103, the pneumatic device of the present disclosure has a better shock absorbing effect than does the prior art, and vibration during the operation can be effectively reduced.
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects, and that one or more features or specific details from one embodiment may be practiced together with one or more features or specific details from another embodiment, where appropriate, in the practice of the disclosure.
While the disclosure has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
