Patent Application
20190203744
The invention relates to a reciprocating pneumatic motor. More specifically, the invention relates to a pneumatic motor having reduced noise as compared to prior art pneumatic motors.
Pneumatic motors are well known in the industry. Typically, pneumatic motors include a cylinder head, a cylinder, a first piston housing, a second piston housing, a piston, and a piston rod. Air is received into an inlet at the cylinder head and the piston rod reciprocates to continuously move the piston right and left. The air flows into the cylinder and the air pressure forces the piston to go down. When the air is vented, the tension from a spring pushes the piston upward. However, one problem with prior-art pneumatic jacks is the noise that accompanies operation of the motor. Disclosed herein are embodiments of air motors that have reduced noise output in comparison with prior art pneumatic motors.
The following presents a simplified summary of the invention in order to provide a basic understanding of some aspects of the invention. This summary is not an extensive overview of the invention. It is not intended to identify critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some concepts of the invention in a simplified form as a prelude to the more detailed description that is presented elsewhere herein.
In one embodiment, a reduced-noise pneumatic motor, includes a housing having a cap disposed at a first end, the cap having an air inlet; a base disposed at a second end, the base having an air outlet hole formed therein configured to at least partially receive a noise damping system, and a piston pump extending therethrough; and bolts extending from the cap to the base to secure the cap and the base to the housing. A pneumatic piston is also disposed within the housing, and includes a shuttle valve situated within a central bore of the pneumatic piston. A piston rod has a first end extending into the piston pump and a second end secured to a spring which biases the piston rod against the pneumatic piston. The air outlet hole has a first portion having a first diameter and a second portion having a second diameter, where the second portion extends partially along the depth of the base. The noise damping system includes a foam member which is received into the second portion of the air outlet hole; a wire mesh component disposed atop the foam member; a retention cap situated atop the wire mesh component; and a bolt that extends through the retention cap and the wire mesh to secure the noise damping system to the base.
In another embodiment, in a reduced-noise pneumatic motor having a housing having a cap disposed at a first end, the cap having an air inlet; a base disposed at a second end, the base having an air outlet hole formed therein, and a piston pump extending therethrough; a pneumatic piston disposed within the housing, the pneumatic piston including a shuttle valve situated within a central bore of the pneumatic piston; and a piston rod having a first end extending into the piston pump and a second end secured to a spring which biases the piston rod against the pneumatic piston; the improvement includes a noise damping system. The noise damping system is configured to engage with the air outlet hole, and includes an air-receiving element. Air exits the pneumatic motor through the air outlet hole, and is received by the air-receiving element, which dampens the sound caused by the air exiting from the pneumatic motor.
In still yet another embodiment, A reduced-noise pneumatic motor has a housing with a cap disposed at a first end, the cap having an air inlet; a base disposed at a second end, the base having an air outlet hole formed therein and configured to at least partially receive a noise damping system, and a piston pump extending therethrough; and bolts extending from the cap to the base to secure the cap and the base to the housing. A pneumatic piston is disposed within the housing, and includes a shuttle valve situated within a central bore of the pneumatic piston. A piston rod has a first end extending into the piston pump and a second end secured to a spring which biases the piston rod against the pneumatic piston.
The base 3 has corresponding holes 31 for receiving the bolts 21. The bolts 21 may be screwed into the holes 31 to maintain the bolts 21 in position. An opening 32 formed into the base 3 receives a pump piston housing 33. An inside diameter of an upper portion of the pump piston housing 33 has a bearing 331, a washer 332, and a seal 333 (e.g., a u-cup seal) which extend through the base 3 and lock onto a piston pump cover 35. A lower portion of the piston pump housing 33 has an oil seal 334, a washer 335, and a hex nut 336.
The piston 4 is a substantially cylindrical body having a first seal ring 41 positioned at the top of the piston 4 and a second seal ring 41′ positioned at the bottom of the piston 4. A piston cap 42 sits atop an indented surface on the top of the piston 4.
As shown in
One end of the piston rod 5 extends through the piston pump cover 35 into the piston pump 33. The other end locks into a spring cap 51 to which a spring 52 is attached. When assembled, the spring cap 51 abuts the bottom of the piston 4. As is known to those of skill in the art, the spring 52 enables the reciprocating motion of the piston rod 5.
In use, compressed air enters through the air inlet opening 23, which pushes the piston 4 forward inside the housing 1, thereby compressing the spring 52. When the seal ring 41 passes by grooves 11 formed in the housing 1 (
A significant amount of noise can be generated by the motor during its operation. This is detrimental for several reasons, not the least of which is the undesirable effects that it can have on the hearing of a person in close proximity to the motor. Accordingly, a motor configuration having reduced noise levels without reducing the efficiency of the motor is desirable. In one embodiment, shown in
The motor 100 may be substantially to the motor 10 described above, except as is set forth below. Reference numerals corresponding to components of the motor 100 are used to identify the same or substantially the same components in the motor 100. In the embodiment shown in
One or more openings 3010 are formed into the base 3000. A first portion 3010a of the opening 3010 having a first diameter extends from an inside surface 3005 through to an outside surface 3007 of the base 3000. In an embodiment, the diameter of the first portion 3010a of the opening 3010 is between about 2 and 4 mm, and preferably about 3 mm. A second portion 3010b of the opening 3010 may extend partially inward from the outside surface 3007 toward the inside surface 3005 of the base 3000. In an embodiment, the diameter of the second portion 3010b of the opening 3010 is between about 10 and 15 mm, and preferably about 12 mm. The second portion 3010b may be recessed approximately 4 to 6 mm deep, measured from the outside surface 3007 of the base 3000.
In the embodiment shown in
A formed piece of foam (or other similar material, such as a sponge) is inserted into the opening second portion 3010b. The foam may be any material that is sufficiently porous and flexible that the air can pass through without significant impedance. For example, materials which may be appropriate include but are not limited to polyurethane (polyester), polyethylene, latex rubber foam, high density charcoal (e.g., Supreem foam), evlon, rebond foam, closed-cell foams, etc. In embodiments, the foam material may be selected based on the foam's ability to absorb sound.
A wire mesh 3020, having an elongated shape is placed adjacent the outside surface 3007 such that it covers the foam piece(s) 3015. The wire mesh 3020 protects the foam pieces 3015 and keeps them in place within the base 3000. A retention cap 3025, having a shape substantially similar to the wire mesh 3020, is situated atop the wire mesh 3020. The retention cap 3025 includes a plurality of holes, through which air may be exhausted. The retention cap 3025 and the wire mesh 3020 (and therefore the foam pieces 3015) are secured to the base 3000 via a mechanical fastener 3030, such as a screw.
In use, the air exits through the motor 100 as described above. Here, however, the foam pieces 3015 absorb a portion of the sound caused by the air escaping from the motor 100. However, because of the porous nature of the foam 3015, the air is not prevented from exiting the motor 100. Likewise, the wire mesh 3020 and the retention cap 3025 include holes which allow the exiting air to escape. Accordingly, the efficiency of the motor 100 is not reduced; however, the noise due to operation of the motor 100 is decreased.
In another embodiment, illustrated in
In still another embodiment, a motor 1000 is substantially similar to the motor 100, as illustrated in
At the outside edge of the base 5000, the diameter of the openings 5010 may be enlarged in order to receive a tube 500, as described below. Accordingly, the openings 5010 may have a first portion 5010a with a first diameter, and a second portion 5010b with a second diameter, the second diameter being larger than the first diameter. The second diameter 5010b of the opening 5010 may be substantially the same as the outside diameter of tubing 500 which may be inserted into the openings such that the tubing 500 is maintained in place in the openings 5010 at least during operation of the motor 1000. Optionally, the tubing 500 may be adhered inside the opening 5010 for a more permanent connection.
The tubing 500 may be any semi-hard plastic tubing, having a diameter of approximately 0.25 inches, although other materials and sizes may additionally or alternately be appropriate and acceptable. Holes 505 may be formed along the length of the tubing 500. In one embodiment, holes 505 in the tubing 500 are formed along two perpendicular planes (e.g., along the x- and y-planes illustrated in
In use, as the air exits the motor 1000 through the openings 5010, it travels down the length of the tubing 500, and exits through the holes 505 formed in the tubing 500. Due to the lengthened path that the air has to exit the motor via the tubing 500, the overall noise of the air motor is reduced.
Generally, the air motors 10, 100, 100 described herein are used with hydraulic jacks, as shown in
Many different arrangements of the described invention are possible without departing from the spirit and scope of the present invention. Embodiments of the present invention are described herein with the intent to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. A skilled artisan may develop alternative means of implementing the disclosed improvements without departing from the scope of the present invention.
Further, it will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures and description need to be carried out in the specific order described. The description should not be restricted to the specific described embodiments.
