1. Field of the Invention
The present invention relates to a scroll apparatus with an axial gap control function, and more particularly to a scroll apparatus capable of controlling the axial gap between a fixed scroll and an orbiting scroll of the scroll apparatus.
2. Description of Related Art
As a traditional scroll apparatus such as a scroll compressor inevitably comes with two substantial drawbacks as described below.
Firstly, when the traditional scroll compressor shuts down, its fixed scroll is in contact with its orbiting scroll, thus giving rise to an increase of frictional force when the scroll compressor is started again.
Secondly, the flange disposed at the top of a frame, a positioning pin and an axial gap plate are fixed at their center to prevent the fixed scroll from rotating. However, the flange, positioning pin and axial gap plate collide with each other during the operation of the scroll compressor, not only making noise, but also giving rise to a leak to the chamber of the scroll compressor. Further, improper wear will occur at the lateral surface and the end surface between the fixed scroll and the orbiting scroll and will reduce the life of use and the reliability of the scroll compressor.
In present scroll compressor related patents, each of these prior arts has its advantages and disadvantages, but none of them can totally overcome the aforementioned shortcomings.
R.O.C. Patent Publication No. 586580 entitled “Improved scroll compressor pump assembly” is illustrated in FIGS. 1 and 2. The compressor 7 comprises an orbiting scroll 74, a fixed scroll 72, a press member 71, a circular base 73, a fixture (not numbered in the figure) for fixing the orbiting scroll 74 and the fixed scroll 72, and a frame 75 mounted into a housing (not shown in the figure) of the compressor. The fixture is fixed onto the periphery of the frame 75 corresponding to the fixed scroll 72 by at least two positioning bases 731, and the positioning bases 731 are fixed onto the frame 75 by the circular base 73. The circular base 73 is coupled with the frame 75 after the frame 75 is fixed inside the housing. The press member 71 is correspondingly fixed to the top of the positioning base 731 and the press member 71 presses on and fixes the fixed scroll 72 and the frame 75, such that an Oldham ring 751 still can be installed between the orbiting scroll 74 and the frame 75, and the limit section 752 of the Oldham ring 751 is provided for limiting the moving direction of the orbiting scroll 74. The fixture still can limit the revolving movement of the orbiting scroll 74 with respect to the fixed scroll 72 and prohibit any rotation so as to change the volume of the compression chamber of the fixed scroll and produce a compression effect to a refrigerant. Therefore, the objective of this prior art resides on reducing any deformation of the mechanical structure during the assembling process of the frame and the housing. Its function resides in improving the assembling precision of the positioning base and the fixed scroll. Its effect resides on changing the volume of the compression chamber of the fixed scroll and the orbiting scroll to produce a compression effect to a refrigerant. Its disadvantages include an increased number of components (press plate), a louder noise (rotation and axial gap) and a large stan-up frictional force.
As disclosed in U.S. Pat. No. 5,407,335, a compressor includes a frame inside a housing, and the frame supports a second scroll and adds a guide post for fixing a fixed scroll into its position and determining the total axial displacement. A circular plate is provided for preventing the rotary movement and axial movement of the fixed scroll, and the guide post is coupled to an end surface of the circular plate, and then secured to the frame by bolts. Therefore, the objective of this prior art is to prevent the axial and rotary movements of the fixed scroll. Its function is to provide an axial compliant function. Its effect is to seal the compression chamber of the fixed scroll and the orbiting scroll and produce a compression effect for the refrigerant. Its advantages includes a more precise positioning of the fixed scroll, a lower noise, and a smaller start-up frictional force. Its disadvantages include an increased number of components and a more complicated axial gap control, which causes a breakdown easily.
As disclosed in U.S. Pat. No. 5,743,720, the fixed scroll is mounted vertically downward to its fixed ring, and its plate spring is installed between its fixed scroll and fixed ring. Therefore, this prior art has the advantages of a reduced number of components, a more precise positioning of the fixed scroll, a lower noise and a smaller start-up frictional force. However, the axial gap control between the two scrolls is still too complicated and will cause a breakdown easily due to its improper control method.
In other words, the aforementioned prior arts have their advantages and disadvantages, but none of them can totally overcome the shortcomings of the prior arts and definitely require further improvements.