Patent Application
20110280754
1. Field of the Invention
The present invention relates to a cam-type pump structure for a refrigerant recycling machine. In particular, a pump apparatus uses a cam-type structure for pistons to be reciprocated in the same direction or in opposite directions so as to pump refrigerant.
2. Description of the Prior Art
Refrigerant is widely used in our daily living, such as domestic refrigerators, air conditioners, refrigerating equipment or car air conditioners. When refrigerators or air conditioners need maintenance, it is required to drain out the refrigerant. This not only pollutes the ambient air but also brings poisonous substances to harm the human body when the refrigerant is burned at a high temperature. Recently, there is a refrigerant recycling machine on the market to pump the refrigerant or the like into a specific container, which conforms to the operation safety and protects the global environment.
The existing refrigerant recycling machine doesn't have a proper design for its inside construction. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to improve the existing products.
The primary object of the present invention is to provide a cam-type pump structure for a refrigerant recycling machine, which comprises two pairs of pistons and cylinders. The two pistons are driven by a cam device. When the cam device is activated, the two pistons are reciprocated synchronously. The pistons are reciprocated in the same direction or in opposite directions. By the motion of the pistons, the present invention provides a high efficiency and is compact in size.
In order to achieve the object, the present invention comprises a main body. The main body comprises a motor at one end thereof. The motor has an output end which is a shaft. The main body has a space therein. The shaft of the motor is disposed in the space. A cam device is inserted on the shaft. The cam device comprises a central rotating body and two eccentric rotating bodies at two sides of the central rotating body. A bearing is provided at an outer end of each of the eccentric rotating bodies. An outer sleeve is provided at an outer end of the bearing. The outer sleeve has a protrusion at one end thereof and a piston at a distal end of the protrusion. The main body has a pair of openings at two sides thereof. Each opening is connected with a cylinder. The cylinder has a chamber therein to receive the piston for reciprocation.
Preferably, a fan is provided at an outer end of the motor to lower the temperature and dissipate the heat when in operation.
Preferably, the main body has a ring portion at an outer edge of the space. The ring portion is covered with a plate to seal the space.
Preferably, each cylinder is connected with a valve body. The inside of the cylinder communicates with the inside of the valve body. The valve body has an inlet and an outlet. The piston is reciprocated in the cylinder to form pressure for the valve body to provide a pump function.
Preferably, the center of the central rotating body of the cam device is formed with an axial hole for insertion of the shaft of the motor. The axial hole penetrates each eccentric rotating body and isn't located at the center of each eccentric rotating body.
Preferably, the centers of the two eccentric rotating bodies are located at different axes. When the shaft is turned to drive the central rotating body, the two eccentric rotating bodies will be turned eccentrically at different angles and the two pistons at the two sides of the cam device will be reciprocated in opposite directions. In this way, the two valve bodies are to pump synchronously, providing a better pump function.
Alternatively, the centers of the two eccentric rotating bodies are located at the same axis. When the shaft is turned to drive the central rotating body, the two eccentric rotating bodies will be turned eccentrically at the same angle and the two pistons at the two sides of the cam device are reciprocated in the same direction. In this way, the two valve bodies are to pump in turn, providing a smooth operation.
Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings.
As shown in
The main body 1 has a casing shape and comprises a motor 11 at one end thereof. A fan 12 is provided at an outer side of the motor 11. The motor 11 has an output end which is a shaft 14. The main body 1 has a space 13 therein. The shaft 14 of the motor 11 is disposed in the space 13. The cam device 2 is inserted on the shaft 14. A distal end of the shaft 14 is provided with a shaft bearing 141. The main body 1 has a pair of openings 15 at two sides thereof to receive the cylinder 3. The main body 1 has a ring portion 16 at an outer edge of the space 13. The main body 1 further comprises a plate 17 and a rubber washer 171 associated with an oil seal ring 161 to seal the space 13. The plate 17 and the rubber washer 171 are connected to the ring portion 16 with screws 172.
The cam device 2 comprises a central rotating body 21, a pair of eccentric rotating bodies 22 at two sides of the central rotating body 21, a pair of bearings 24 next to the pair of eccentric rotating bodies 22 and a pair of outer sleeves 25 next to the pair of the bearings 24. Each outer sleeve 25 has a protrusion 26 at one end thereof and a piston 27 at a distal end of the protrusion 26. The cam device 2 has an axial hole 23 along a central axis thereof. In this embodiment, the axial hole 23 penetrates through the center of the central rotating body 21, but not through the center of each eccentric rotating body 22.
The cylinder 3 is coupled to the opening 15 of the main body 1. The cylinder 3 has a chamber 31 therein to receive the piston 27 for reciprocating motion. Preferably, there are two openings 15 in this embodiment, so the cylinder 3 corresponds in number to the opening 15.
The valve body 4 is mounted on the cylinder 3. The inside of the cylinder 3 communicates with the inside of the valve body 4. The valve body 4 has an inlet 41 and an outlet 42. The piston 27 is reciprocated in the cylinder 3 to form pressure for the valve body 4 to provide a pump function.
When the motor 11 is started, the shaft 14 will be driven to turn the cam device 2 on the shaft 14. The central rotating body 21 and the two eccentric rotating bodies 22 are turned synchronously. Because the axial hole 23 is not disposed at the center of each eccentric rotating body 22, the cam device 2 is turned eccentrically. As shown in
When the motor 11 is started, the shaft 14 will be driven to turn the cam device 5 on the shaft 14. The central rotating body 51 and the two eccentric rotating bodies 52 are turned synchronously. Because the axial hole 53 is not disposed at the center of each eccentric rotating body 52, the cam device 5 is turned eccentrically. As shown in
Although particular embodiments of the present invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the present invention. Accordingly, the present invention is not to be limited except as by the appended claims.
