阅读说明：本技术 一种凸轮曲轴机构及活塞式压缩机 (Cam crankshaft mechanism and piston compressor ) 是由 杜金尧 徐敏 刘源泉 李亚荣 于 2021-09-18 设计创作，主要内容包括：本发明属于压缩机领域,尤其涉及一种凸轮曲轴机构及活塞式压缩机,凸轮曲轴机构包括凸轮曲轴,凸轮曲轴包括曲轴杆,曲轴杆的第一端连接电机的输出端,曲轴杆的第二端形成一端面,端面的外侧边缘形成一环状的轨道槽,轨道槽呈中心对称设置,且轨道槽相互垂直的两条对称轴在端面上的长度不相等；连接件,包括连杆,和分别位于连杆两端的第一连接部和第二连接部,第一连接部与轨道槽配合并可相对轨道槽滑动,第二连接部与压缩机活塞配合；电机驱动曲轴杆转动时,第一连接部在轨道槽内滑动,连杆带动压缩机活塞前后移动。本发明的凸轮曲轴机构能提高活塞式压缩机的排量及制冷量。(The invention belongs to the field of compressors, and particularly relates to a cam crankshaft mechanism and a piston compressor, wherein the cam crankshaft mechanism comprises a cam crankshaft, the cam crankshaft comprises a crankshaft rod, the first end of the crankshaft rod is connected with the output end of a motor, the second end of the crankshaft rod forms an end face, the outer edge of the end face forms an annular track groove, the track grooves are arranged in a centrosymmetric manner, and the lengths of two symmetrical shafts which are perpendicular to each other in the track groove on the end face are unequal; the connecting piece comprises a connecting rod, a first connecting part and a second connecting part, wherein the first connecting part and the second connecting part are respectively positioned at two ends of the connecting rod; when the motor drives the crankshaft rod to rotate, the first connecting part slides in the track groove, and the connecting rod drives the compressor piston to move back and forth. The cam crankshaft mechanism of the invention can improve the discharge capacity and the refrigerating capacity of the piston compressor.)

1. A cam crankshaft mechanism is characterized by comprising

The cam crankshaft comprises a crankshaft rod, the first end of the crankshaft rod is connected with the output end of the motor, the second end of the crankshaft rod forms an end face, the outer edge of the end face forms an annular track groove, the track grooves are arranged in a centrosymmetric mode, and the lengths of two symmetrical shafts, perpendicular to each other, of the track grooves on the end face are unequal;

the connecting piece comprises a connecting rod, a first connecting part and a second connecting part, wherein the first connecting part and the second connecting part are respectively positioned at two ends of the connecting rod; when the motor drives the crankshaft rod to rotate, the first connecting part slides in the track groove, and the connecting rod drives the compressor piston to move back and forth.

2. The cam-crankshaft mechanism according to claim 1, wherein two sides of the track groove located at the short symmetry axis of the track groove are respectively recessed towards opposite sides to form a first concave arc section and a second concave arc section, two sides of the track groove located at the long symmetry axis of the track groove are raised towards opposite sides to form a first convex arc section and a second convex arc section, and the first convex arc section, the first concave arc section, the second convex arc section and the second concave arc section are connected in pairs to form the track groove.

3. A cam-crank mechanism according to claim 1 or 2, wherein the side of the compressor piston adjacent to the second connecting portion is recessed inwardly to form a mounting cavity, the second connecting portion being located in the mounting cavity; a first channel is formed in the first connecting part, and a second channel is formed in the second connecting part; the cam crankshaft mechanism also comprises

A first end of the connecting pin extends into the first channel and is in interference fit with the first channel, and a second end of the connecting pin extends into the track groove and is in clearance fit with the track groove;

a wrist pin located within the second passage and having at least one end thereof extending out of the second passage and fixedly engaging the compressor piston via a fastener.

4. The cam-crankshaft mechanism according to claim 3, wherein the inner walls of the track groove are protruded to opposite sides to form a limit protruding ring, and the second end of the connecting pin is limited in the limit protruding ring and is in clearance fit with the limit protruding ring.

5. The cam-crankshaft mechanism according to claim 3, wherein said cam-crankshaft mechanism comprises a balance structure, said balance structure is disposed to protrude from said end surface, said balance structure is formed with a plurality of oil outlet holes;

a first oil duct is formed between the balance structure and the crankshaft rod, a first end of the first oil duct is located inside the crankshaft rod, a second end of the first oil duct extends from the inside of the crankshaft rod to the inside of the balance structure, a plurality of channels are formed in the balance structure in a branching mode, and the channels are communicated with the oil outlets in a one-to-one correspondence mode.

6. The cam-crank mechanism of claim 5, wherein the crank shaft has an oil applying passage formed therein, and the outer wall of the crank shaft has a second oil passage formed therein, a first end of the second oil passage communicating with the first connecting hole of the oil applying passage, and a second end of the second oil passage spiraling around the outer peripheral wall of the crank shaft to communicate with the first end of the first oil passage.

7. The cam-crankshaft mechanism according to claim 6, wherein an air outlet is formed on the end surface, an air outlet channel is formed between the end surface and the crankshaft rod, a first end of the air outlet channel is communicated with the second connecting hole of the upper oil channel, and a second end of the air outlet channel extends from the second connecting hole of the upper oil channel to the direction of the air outlet from the inside of the crankshaft rod to be communicated with the air outlet.

8. The cam-crankshaft mechanism according to claim 7, wherein said bottom wall of said track groove is formed with a plurality of oil leakage holes.

9. A cam-crankshaft mechanism according to any of claims 4-8, characterized in that the inside of the connecting pin is provided with a passage through the inside of the connecting pin.

10. A piston compressor, characterized in that it comprises a cylinder block in which a cam-crank mechanism according to any of claims 1-9 is arranged.

Technical Field

The invention belongs to the field of compressors, and particularly relates to a cam crankshaft mechanism and a piston compressor.

Background

Generally, refrigeration compressors are classified according to their control principles and can be classified into variable frequency compressors and fixed frequency compressors. In order to achieve the purposes of energy conservation and environmental protection or meet the requirement of large refrigerating capacity, the variable-frequency piston compressor occupies most of the market of the refrigerator industry. The prior reciprocating piston compressor mainly realizes the supply of different refrigerating capacities by changing the rotating speed, but because of the limitation of the structural scheme of the piston compressor, the displacement and the refrigerating capacity of the piston compressor are difficult to improve in a space with compact structure,

the present invention has been made in view of this situation.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a cam crankshaft mechanism capable of improving the discharge capacity and the refrigerating capacity of a piston type compressor and the piston type compressor.

In order to solve the above technical problem, the present invention provides a cam crankshaft mechanism, comprising

The cam crankshaft comprises a crankshaft rod, the first end of the crankshaft rod is connected with the output end of the motor, the second end of the crankshaft rod forms an end face, the outer edge of the end face forms an annular track groove, the track grooves are arranged in a centrosymmetric mode, and the lengths of two symmetrical shafts, perpendicular to each other, of the track grooves on the end face are unequal;

the connecting piece comprises a connecting rod, a first connecting part and a second connecting part, wherein the first connecting part and the second connecting part are respectively positioned at two ends of the connecting rod; when the motor drives the crankshaft rod to rotate, the first connecting part slides in the track groove, and the connecting rod drives the compressor piston to move back and forth.

Further optionally, be located the short symmetry axis department in track groove the both sides in track groove are sunken to the offside respectively and form first concave arc section and second concave arc section, be located the long symmetry axis department in track groove the both sides branch of track groove is protruding to the offside and is formed first convex arc section and second convex arc section, first convex arc section first concave arc section second convex arc section and second concave arc section two liang link to each other and form the track groove.

Further optionally, one side of the compressor piston, which is close to the second connecting portion, is recessed inwards to form a mounting cavity, and the second connecting portion is located in the mounting cavity; a first channel is formed in the first connecting part, and a second channel is formed in the second connecting part; the cam crankshaft mechanism also comprises

A first end of the connecting pin extends into the first channel and is in interference fit with the first channel, and a second end of the connecting pin extends into the track groove and is in clearance fit with the track groove;

a wrist pin located within the second passage and having at least one end thereof extending out of the second passage and fixedly engaging the compressor piston via a fastener.

Further optionally, the inner walls of the two sides of the track groove respectively protrude towards the opposite sides to form limiting convex rings, and the second end of the connecting pin is limited in the limiting convex rings and is in clearance fit with the limiting convex rings.

Further optionally, the cam crankshaft mechanism comprises a balance structure, the balance structure protrudes out of the end face, and a plurality of oil outlet holes are formed in the balance structure;

a first oil duct is formed between the balance structure and the crankshaft rod, a first end of the first oil duct is located inside the crankshaft rod, a second end of the first oil duct extends from the inside of the crankshaft rod to the inside of the balance structure, a plurality of channels are formed in the balance structure in a branching mode, and the channels are communicated with the oil outlets in a one-to-one correspondence mode.

Further optionally, an oil applying channel is formed inside the crankshaft rod, a second oil channel is formed on the outer wall of the crankshaft rod, a first end of the second oil channel is communicated with the first connecting hole of the oil applying channel, and a second end of the second oil channel extends around the outer peripheral wall of the crankshaft rod in a spiral mode to be communicated with the first end of the first oil channel.

Further optionally, an air outlet is formed in the end face, an air outlet channel is formed between the end face and the crankshaft rod, a first end of the air outlet channel is communicated with the second connecting hole of the upper oil channel, and a second end of the air outlet channel extends from the inside of the crankshaft rod to the air outlet direction from the second connecting hole of the upper oil channel to be communicated with the air outlet.

Further optionally, a plurality of oil leakage holes are formed in the bottom wall of the rail groove.

Further optionally, the interior of the connecting pin is provided with a passage through the interior of the connecting pin.

The embodiment also provides a piston compressor, which comprises a cylinder block, wherein the cylinder block is provided with the cam crankshaft mechanism.

After adopting the technical scheme, compared with the prior art, the invention has the following beneficial effects:

compared with the conventional crank connecting rod mechanism, the cam crankshaft mechanism provided by the invention has the advantages that the motor rotor drives the cam crankshaft to rotate, and the cam crankshaft can drive the piston to reciprocate twice, so that gas in the cylinder is compressed twice, the discharge capacity of the piston compressor is improved by 64 percent, and the refrigerating capacity and the energy efficiency of the compressor are greatly improved.

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention, are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without limiting the invention to the right. It is obvious that the drawings in the following description are only some embodiments, and that for a person skilled in the art, other drawings can be derived from them without inventive effort. In the drawings:

fig. 1 is a perspective view of a cam crankshaft according to an embodiment of the present invention.

Fig. 2 is a front sectional view of the cam crank mechanism according to the embodiment of the present invention.

Fig. 3 is a left side sectional view of the cam crank mechanism according to the embodiment of the present invention.

Fig. 4 is a plan view of the cam crank mechanism according to the embodiment of the present invention.

Fig. 5 is a perspective view of a connecting member of the cam crank mechanism according to the embodiment of the present invention.

Fig. 6 is a perspective view of a slide connecting pin of the cam crank mechanism according to the embodiment of the present invention.

Fig. 7 is a top-dead-center sectional view of the cam-crank mechanism of the embodiment of the present invention driving the piston to move.

FIG. 8 is a cross-sectional view of the cam-crank mechanism driving the piston to move to the bottom dead center according to the embodiment of the present invention.

Fig. 9 is a diagram comparing piston strokes of the conventional crank mechanism and the cam crank mechanism of the present embodiment.

Wherein: 10-a cylinder block; 20-a cam crankshaft; 21-a balanced structure; 22-a track groove; 23-crankshaft rod; 24-a second oil passage; 25-oiling channel; 26-a limit convex ring; 27-air outlet holes; 28-oil outlet holes; 29. a first oil passage; 30-a piston; 40-a connecting rod; 41-a second connection; 42-a first connection; 50-piston pin; 60-connecting pins; 70-a bearing assembly; 80-fixed pins.

It should be noted that the drawings and the description are not intended to limit the scope of the inventive concept in any way, but to illustrate it by a person skilled in the art with reference to specific embodiments.

Detailed Description

In the description of the present invention, it should be noted that the terms "inside", "outside", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and operate, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "contacting," and "communicating" are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

At present, the reciprocating piston 30 compressor mainly realizes the supply of different refrigerating capacities by changing the rotating speed, but due to the limitation of the structural scheme of the piston 30 compressor, the improvement of the discharge capacity and the refrigerating capacity of the piston 30 compressor in a space with a compact structure is very difficult, the embodiment skillfully utilizes the limited space in the piston 30 compressor, designs a double-stroke cam crankshaft 20 and connecting rod 40 mechanism, and can greatly improve the discharge capacity of the piston 30 compressor. The cam crankshaft 20 mechanism of the present embodiment, as shown in fig. 1-6, includes a cam crankshaft 20 and a connecting member, the cam crankshaft 20 includes a crankshaft 23, a first end of the crankshaft 23 is connected to an output end of the motor, a second end of the crankshaft 23 forms an end face, an outer edge of the end face forms an annular track groove 22, the track groove 22 is disposed in a central symmetry manner, and lengths of two symmetry axes perpendicular to the track groove 22 on the end face are different. The symmetrical structural design can make the crankshaft reach dynamic balance well and eliminate the rotation inertia force of the crankshaft.

The connecting member includes a connecting rod 40, and a first connecting portion 42 and a second connecting portion 41 respectively located at both ends of the connecting rod 40, as shown in fig. 5, 7 and 8, the first connecting portion 42 is engaged with the track groove 22 and is slidable with respect to the track groove 22, and the second connecting portion 41 is engaged with the compressor piston 30; when the motor drives the crank shaft 23 to rotate, the first connecting portion 42 slides in the track groove 22, and the connecting rod 40 moves the compressor piston 30 back and forth. In some embodiments, the first connecting portion 42 is matched with the track groove 22 in such a way that the first connecting portion 42 directly extends into the track groove 22 with a small size to be in clearance fit with the track groove 22, and in other embodiments, the bottom of the first connecting portion 42 is fixed with or extends to form a plug connector which extends into the track groove 22 to be in clearance fit with the track groove 22. In some embodiments, the second connection portion 41 is engaged with the compressor piston 30 such that the second connection portion 41 is directly and fixedly connected with the compressor piston 30, and in other embodiments, the second connection portion 41 is engaged with the compressor piston 30 such that the second connection portion 41 is detachably or fixedly connected with the compressor piston 30 through other components.

Because the assembly process of the crank connecting rod structure of the existing piston compressor needs to process a U-shaped groove at the upper end of the cylinder hole of the cylinder seat, the assembly of the connecting rod is convenient, and the cam crankshaft mechanism of the embodiment cancels the processing of the U-shaped groove of the cylinder seat, thereby reducing the process cost.

As shown in fig. 1 and 4, the track grooves 22 are arranged in a central symmetry manner, and the lengths of two symmetry axes perpendicular to each other of the track grooves 22 on the end surfaces are unequal, so that the distances from the central point of the track groove 22 to two opposite sides of the track groove 22 are different, when the motor drives the crank shaft 23 to rotate, the first connecting portion 42 moves in the track, and the first connecting portion 42 is located at the farthest end of the track groove 22 from the central point and drives the compressor piston 30 to be at the top dead center, as shown in fig. 7. The first connecting portion 42 is located at the nearest end of the track groove 22 from the center point and drives the compressor piston 30 to be at the bottom dead center, as shown in fig. 8. Because the first connecting part 42 can alternatively move between the two farthest ends and the two nearest ends in one rotation period of the crank rod 23, the compressor piston 30 can reciprocate twice in one rotation period of the crank rod 23, gas in the compressor cylinder can be compressed twice, the displacement of the compressor of the piston 30 is improved by 64 percent, and the refrigerating capacity and the energy efficiency of the compressor are greatly improved.

Further alternatively, since the stroke of the compressor piston 30 moving from the top dead center to the bottom dead center is related to the distance between the farthest end of the track groove 22 and the nearest end of the track groove 22 from the center point, that is, the stroke of the compressor piston 30 is equal to the distance between the farthest end of the track groove 22 and the center point-the distance between the nearest end of the track groove 22 and the center point, in order to increase the stroke of the compressor piston 30, it is necessary to increase the distance between the farthest end of the track groove 22 and the center point, and to decrease the distance between the nearest end of the track groove 22 and the center point, therefore, the present embodiment forms the first concave arc section and the second concave arc section by respectively recessing the two sides of the track groove 22 at the short symmetry axis of the track groove 22 to the opposite sides, forms the first convex arc section and the second convex arc section by protruding the two sides of the track groove 22 at the long symmetry axis of the track groove 22 to the opposite sides, the first convex arc section, the first concave arc section, the second convex arc section, The second convex arc segment and the second concave arc segment are connected two by two to form the track groove 22, as shown in fig. 1 and 4. The orbital slot 22 is designed to increase the stroke of the compressor piston 30 to further increase the compressor displacement and cooling capacity.

Further alternatively, as shown in fig. 7 and 8, one side of the compressor piston 30 close to the second connecting portion 41 is recessed inwards to form a mounting cavity, and the second connecting portion 41 is located in the mounting cavity; a first channel is formed in the first connecting portion 42, and a second channel is formed in the second connecting portion 41; the cam-crankshaft 20 mechanism further includes a connecting pin 60, a first end of the connecting pin 60 extends into the first channel and is in interference fit with the first channel, and a second end of the connecting pin 60 extends into the track groove 22 and is in clearance fit with the track groove 22; the cam crankshaft 20 mechanism further includes a wrist pin 50, the wrist pin 50 being located within the second passage, and at least one end of the wrist pin 50 extending out of the second passage and fixedly engaging the compressor piston 30 via a stationary member. As shown in fig. 7 and 8, the fixing member may be optionally a fixing pin 80. The cam crankshaft 20 rotates to drive the connecting pin 60 to move in the track groove 22, the connecting pin 60 slides to drive the connecting rod 40 to move back and forth, and the connecting rod 40 moves back and forth to drive the piston 30 to move back and forth.

Further alternatively, as shown in fig. 1-3, the inner walls of the two sides of the track groove 22 are respectively protruded to the opposite sides to form a limiting convex ring 26, the second end of the connecting pin 60 is limited in the limiting convex ring 26 and is in clearance fit with the limiting convex ring 26, and the setting of the limiting convex ring 26 plays a role in guiding and positioning the connecting pin 60.

Further alternatively, as shown in fig. 1-3, the cam crankshaft 20 mechanism comprises a balance structure 21, the balance structure 21 is disposed with a protruding end surface, and a plurality of oil outlet holes 28 are formed on the balance structure 21; as shown in fig. 2, 3 oil outlet holes 28 are formed in the balance structure 21, the number of the oil outlet holes 28 is not limited to 3, and the number of the oil outlet holes 28 can be adjusted as needed. The refrigerant oil is subjected to centrifugal force, and the oil can be sufficiently supplied to each portion of the compressor piston 30. Alternatively, the oil outlet holes 28 are respectively located at different orientations of the balance structure 21, thereby further facilitating the oil thrown from the oil outlet holes 28 to be uniformly supplied to various portions of the piston 30. A first oil channel 29 is formed between the balance structure 21 and the crankshaft 23, a first end of the first oil channel 29 is located inside the crankshaft 23, a second end of the first oil channel 29 extends from the inside of the crankshaft 23 to the inside of the balance structure 21, and the first oil channel branches inside the balance structure 21 to form a plurality of channels, and the channels are respectively communicated with the oil outlet holes 28 in a one-to-one correspondence mode. An upper oil passage 25 is formed inside the crank shaft 23, a second oil passage 24 is formed on an outer wall of the crank shaft 23, a first end of the second oil passage 24 is communicated with a first connection hole of the upper oil passage 25, and a second end of the second oil passage 24 spirals around an outer peripheral wall of the crank shaft 23 to be communicated with a first end of the first oil passage 29. Optionally, the oil feeding channel 25 is arranged in an eccentric structure, so as to increase the rotation radius of the oil feeding channel, according to the calculation formula w of centrifugal oil pumping, 2 × g × h/R ^2, and under the condition that the angular velocity w is not changed, the larger R is, the larger the oil pumping height h is, and the better the oil pumping effect is.

An oil pumping structure is arranged in or below the upper oil passage 25, the oil pumping structure pumps oil in an oil pool at the bottom of the compressor of the piston 30 into the upper oil passage 25, and oil in the upper oil passage 25 is supplied to the balance structure 21 along the second oil passage 24 and the first oil passage 29 to lubricate the whole mechanism.

Further optionally, as shown in fig. 1 to 4, an air outlet 27 is formed on the end surface, an air outlet channel is formed between the end surface and the crankshaft 23, a first end of the air outlet channel is communicated with the second connecting hole of the upper oil channel 25, a second end of the air outlet channel extends from the inside of the crankshaft 23 to the direction of the air outlet 27 through the second connecting hole of the upper oil channel 25 to be communicated with the air outlet 27, and the air outlet 27 is configured to maintain the air pressure balance in the upper oil channel 25, so that the oil in the compressor oil sump can be better pumped into the upper oil channel 25. The existence of the air outlet hole 27 causes the center of mass of the upper end of the crankshaft to deviate, and in order to realize the dynamic balance of the cam crankshaft 20, the arrangement position of the balance structure 21 deviates from the geometric center of the cam crankshaft 20 to the opposite direction of the arrangement position of the air outlet hole 27, as shown in fig. 4, the air outlet hole 27 is positioned between the center point of the track groove 22 and the farthest end of the track groove 22, so that the existence of the air outlet hole 27 causes the center of mass of the crankshaft to deviate to the left, and the balance structure 21 is arranged at the position of the geometric center of the cam crankshaft 20 to deviate to the right.

Further optionally, a plurality of oil leakage holes are formed in the bottom wall of the track groove 22, so that oil accumulation in the track groove 22 is prevented from affecting the height of an oil pool at the bottom of the compressor of the piston 30 and affecting oil pumping.

Further alternatively, as shown in fig. 6, the inside of the connecting pin 60 is provided with a passage penetrating the inside of the connecting pin 60, thereby preventing the possibility that the refrigerant oil cannot be supplied to the lower end of the first connecting portion 42.

The operation of the cam-crankshaft 20 mechanism of the present embodiment is as follows: the motor rotor drives the cam crankshaft 20 to rotate, the track groove 22 drives the connecting pin 60 to move in the track, the sliding connecting pin 60 drives the connecting rod 40 and the piston 30 to reciprocate, and the motion track of the connecting rod 40 is a straight line, which is different from the motion track of the cam crankshaft 20. The state of one cycle stroke of the piston 30 shown in fig. 7 and 8 is the closed loop from fig. 7 → fig. 8 → fig. 7.

Fig. 9 is a comparison graph of the stroke of the piston 30 of the conventional crank mechanism and the cam-crankshaft 20 mechanism of the present embodiment, compared with the conventional crank mechanism, the cam-crankshaft 20 mechanism of the present embodiment can perform two times of compression by the piston 30 under the condition that the cam-crankshaft 20 rotates once, the displacement of the piston 30 compressor is increased by 64%, and the cooling capacity and energy efficiency of the compressor are greatly improved.

The embodiment also provides a piston 30 type compressor, wherein the piston 30 type compressor comprises a cylinder block 10, and the cam crankshaft 20 mechanism is arranged in the cylinder block 10. A bearing assembly 70 is provided between the lower surface of the end surface of the cam crankshaft 20 and the cylinder block 10, to reduce the friction force of the rotation of the cam crankshaft 20.

Although the present invention has been described with reference to a preferred embodiment, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims.