Split crankcase of refrigeration compressor

Abstract

The utility model discloses a split type crankcase of a refrigeration compressor, which relates to liquid variable volume machinery, the split type crankcase comprises a crankcase base, a shaft hole body and a cylinder hole body, the shaft hole body is fixedly connected with the crankcase base, and the cylinder hole body is fixedly connected with the crankcase base. Compared with the prior art that a crankshaft seat and an air cylinder seat are fixedly connected with a box body base through bolts, the assembling precision of a crankcase is easily affected. According to the utility model, the crankcase base and the shaft hole body as well as the crankcase base and the cylinder hole body are in interference fit, so that the matching is firm and high in precision, and the assembly process is also simple. And moreover, a piston and a cylinder hole body oil groove can be additionally arranged in the cylinder hole body, so that the performance of the crankcase is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to liquid variable volume type machinery, concretely relates to a kind of split type crankcase of refrigeration compressor specially applicable to the parts, component or accessory of pump or pumping system of elastic fluid. BACKGROUND

[0002] Refrigeration compressor for refrigerator has a long history, and almost all refrigeration compressor crankcases for refrigerator are integrally formed by pouring, and the cast iron blanks formed need to be finally put into use through complex processes. Generally, after the crankcase casting is demoulded, it needs to be processed by at least five large special equipment, and five sets of large special clamps are matched, including the processing of high-pressure cavity hole and screw hole, the processing of stator surface and cylinder surface, the processing of drain hole, the processing of outer bearing surface, and the honing processing of shaft hole and cylinder hole.

[0003] With the diversification of market demand and the increasingly fast updating speed of products, the types of crankcases are increasingly diversified, the crankcase processing equipment is special, and the crankcase itself is also one-to-one special for compressor, so as to cause the sharp rise of equipment cost, processing cost and organization cost.

[0004] Therefore, the split type crankcase has greater efficiency and cost advantage compared with the traditional integrally formed crankcase in special design and processing for specific equipment. Although the prior art also has a split type crankcase, such as the "split type crankcase for refrigerator compressor" disclosed in the announcement No. CN210859129U, the fixing of crankshaft seat and base of the box body adopts bolt connection, and the cylinder seat and the crankshaft seat are also connected by utility bolt, which is too high in requirement for screw hole processing of split part and base part and assembly equipment, and the probability of unqualified products is relatively large in actual application process. UTILITY MODEL CONTENTS

[0005] The utility model aims at processing crankcase base, shaft hole body and cylinder hole body separately, reducing processing difficulty, and enabling the crankcase to be assembled according to equipment, so as to be high in production efficiency. Another object of the utility model is to adopt interference fit between crankcase base and shaft hole body and between crankcase base and cylinder hole body, so as to be firm and high in precision, and the assembly process is simple.

[0006] The utility model achieves the above technical objects through the following technical means.

[0007] A split type crankcase of refrigeration compressor, characterized by comprising crankcase base, shaft hole body and cylinder hole body, the shaft hole body is fixedly connected with the crankcase base, and the cylinder hole body is fixedly connected with the crankcase base.

[0008] The shaft hole body mounting hole and the cylinder hole body mounting hole are cross and perpendicular.

[0009] Further, the cylinder hole body mounting hole is located in the middle of the planar part of the crankcase base.

[0010] Further, the cylinder hole body mounting hole is a through hole, and the cylinder hole body mounting hole is in interference fit with the cylinder hole body.

[0011] As preferred, the cylinder hole body is provided with a piston, and the piston 4 is a stepped cylindrical structure, the outer diameter of both ends is equal to the inner diameter of the cylinder hole body, and the outer diameter of the middle part is smaller than that of both ends.

[0012] Further, the shaft hole body mounting hole provided on the crankcase base is a stepped hole, the shaft hole body mounting hole is provided with an upper fitting hole section and a lower fitting hole section, and the diameter of the upper fitting hole section is greater than that of the lower fitting hole section.

[0013] As preferred, the cylinder hole body is a thin-walled hollow tube structure, and the inner wall of the cylinder hole body is provided with an annular cylinder hole body oil groove.

[0014] Further, the shaft hole body is a stepped shaft provided with a hole in the center, the outer wall of the shaft hole body is respectively an upper fitting shaft section and a lower fitting shaft section from top to bottom, and the diameter of the upper fitting shaft section is greater than that of the lower fitting shaft section.

[0015] Further, the shaft hole body is in interference fit with the shaft hole body mounting hole, the upper fitting shaft section is in interference fit with the upper fitting hole section, and the lower fitting shaft section is in interference fit with the lower fitting hole section.

[0016] Further, the outer wall of the cylinder hole body is fixedly installed with the crankcase base, the cylinder hole body is provided with a piston, and the inner wall of the cylinder hole body is in close fit with the piston.

[0017] As preferred, the crankcase base and the shaft hole body and the cylinder hole body are castings.

[0018] The utility model has the following gain effects:

[0019] Compared with the prior art that the crankshaft seat and the cylinder seat are fixedly connected with the box base through bolts, the assembly precision of the crankcase is easily affected. The utility model adopts interference fit between the crankcase base and the shaft hole body and between the crankcase base and the cylinder hole body, the fit is firm and the precision is high, and the assembly process is simple. The utility model improves the qualified rate and the production efficiency of products, and the piston and the cylinder hole body oil groove can be added in the cylinder hole body, and the performance of the crankcase is improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is the three-dimensional structure schematic view of the crankcase base of the utility model.

[0021] Figure 2 It is the assembly section view of the crankcase of the utility model.

[0022] Figure 3 It is the explosion section view of the crankcase of the utility model.

[0023] Figure 4 It is the structure schematic view of the shaft hole body of the utility model.

[0024] Figure 5 It is the structure schematic view of the cylinder hole body of the utility model.

[0025] In the drawing, 1-crankcase base, 11-cylinder hole body matching part, 12-cylinder hole body mounting hole, 13-shaft hole body mounting hole, 131-upper matching hole section, 132-lower matching hole section, 2-shaft hole body, 21-upper matching shaft section, 22-lower matching shaft section, 3-cylinder hole body, 31-cylinder hole body oil groove, 4-piston. DETAILED DESCRIPTION

[0026] The utility model will be further explained in connection with the drawings and specific embodiments, but the protection scope of the utility model is not limited to this.

[0027] Example one:

[0028] As Figures 1 to 5 Indicated, a split type crankcase of refrigeration compressor, including crankcase base 1 and cylinder hole body 3 and shaft hole body 2, the fixed connection between the shaft hole body 2 and the crankcase base 1, the fixed connection mode is interference fit, the fixed connection between the cylinder hole body 3 and the crankcase base 1. The connection mode between the fixed connection mode and the shaft hole body 2 and the crankcase base 1 is identical, and the interference fit between the cylinder hole body 3 and the crankcase base 1 is also realized.

[0029] The refrigeration compressor for refrigerator has a long history, and almost all the crankcase of refrigeration compressor for refrigerator is integrally formed by pouring, and the cast iron blank formed needs to pass through complex processes to finally put into use. Generally speaking, the crankcase casting needs to pass through the processing of at least five large special equipment after demoulding, and is matched with five sets of large special clamps, including the processing of high-pressure cavity hole and screw hole, the processing of stator face and cylinder face, the processing of drain hole, the processing of outer bearing face, the honing processing of shaft hole and cylinder hole.

[0030] With the diversification of market demand and the increasingly fast updating speed of products, the types of crankcases are increasingly diversified, the crankcase processing equipment is special, and the crankcase itself is also one-to-one special for the compressor, so as to cause the sharp rise of equipment cost, processing cost and organization cost.

[0031] Part of the crankcases is split crankcases, but this part of the split crankcases is connected through screws, and the perpendicularity of shaft holes and cylinder holes, the coaxiality and cylindricity of shaft holes and outer bearing holes on the crankcases are extremely high, and the cylindricity is required to reach 50 microns, so the screw holes of the split part and the base part of the split crankcase are too high for the processing and assembly equipment, and the probability of unqualified products is relatively high in the actual application process.

[0032] Moreover, in the actual use of the large-diameter cylinder hole, the existing large-diameter piston matching surface matched with the cylinder hole needs to be processed with an oil groove, and the number of the oil groove can be one or more. Due to the bolt fixation, the inner cylindrical surface of the cylinder hole can not be a complete cylindrical surface, in order to ensure the cylindricity and other key shape and position tolerances of the piston, the processing difficulty of the oil groove is relatively large.

[0033] In summary, the forming and processing of the crankcase of the refrigerator refrigeration compressor are difficult, the whole process cost is high, the precision of the final part is difficult to guarantee, and different specifications are diversified and cannot be replaced, which brings many inconveniences to production, development and operation.

[0034] And in the embodiment, a split crankcase of a refrigeration compressor is provided, compared with the traditional integrated crankcase, the utility model is split crankcase structure. On the one hand, the mold of the crankcase of the utility model is not as complex as the mold structure of the traditional integrated crankcase. Moreover, after each part is made, the surface is more flat than the integrated integrated crankcase, less processing is required, and high-precision threaded holes do not need to be processed for the fixation and installation of the crankcase base 1, the shaft hole body 2 and the cylinder hole body 3 like the existing split crankcase. The installation is more convenient.

[0035] The main body of the crankcase base 1 is a plate structure, a cuboid cylinder hole body matching part 11 is arranged on the plate structure of the crankcase base 1, and a cylinder hole body mounting hole 12 is arranged at the middle position of the cuboid cylinder hole body matching part 11. The axis of the cylinder hole body mounting hole 12 is parallel to the surface of the plate structure of the crankcase base 1, and the inner cylindrical surface of the cylinder hole body mounting hole 12 is close to tangent to the upper surface of the plate structure of the crankcase base 1.

[0036] The cylinder hole body mounting hole 12 is a through hole structure, that is, the cylinder hole body mounting hole 12 is a through hole provided in the cylinder hole body fitting part 11 in a cuboid shape. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed by interference fit, so that the cylinder hole body 3 is fixed on the cylinder hole body mounting hole 12.

[0037] The interference fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 can use liquid nitrogen or other low-temperature substances to cool the cylinder hole body 3, so that the cylinder hole body 3 shrinks when cold. The tolerance band of the cylinder hole body 3, which is originally above the tolerance band of the cylinder hole body mounting hole 12, falls below the tolerance band of the cylinder hole body mounting hole 12, so that the cylinder hole body 3 can be easily put into the cylinder hole body mounting hole 12, thereby fixing and mounting the cylinder hole body 3 and the cylinder hole body mounting hole 12.

[0038] When the temperature of the cylinder hole body 3 returns to room temperature, the tolerance band of the cylinder hole body 3 returns to above the tolerance band of the cylinder hole body mounting hole 12, so that the outer surface of the cylinder hole body 3 is pressed against the inner wall of the cylinder hole body mounting hole 12, tightly contacts, and forms interference fit. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed together.

[0039] Because the cylinder hole body 3 and the cylinder hole body mounting hole 12 are complete cylindrical surface structures that are not damaged, the specific position or angle of the fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 does not need to be considered, and the fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 does not need to consider the restriction of other structures except the hole shaft fit, so the assembly is convenient.

[0040] The interference fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 can also choose to heat the cylinder hole body mounting hole 12 to increase the inner diameter of the cylinder hole body mounting hole 12. Under the same or similar temperature conditions, the outer wall diameter of the cylinder hole body 3 is the same as that of the cylinder hole body mounting hole 12, but the tolerance band of the outer wall of the cylinder hole body 3 is above that of the cylinder hole body mounting hole 12.

[0041] Therefore, under normal circumstances, the cylinder hole body 3 cannot be put into the cylinder hole body mounting hole 12, so the cylinder hole body mounting hole 12 is heated to cause the hole diameter of the cylinder hole body mounting hole 12 to expand, and the tolerance band of the cylinder hole body mounting hole 12 is above the tolerance band of the cylinder hole body 3, so that the cylinder hole body 3 can be put into the inside of the cylinder hole body mounting hole 12.

[0042] When the cylinder hole body mounting hole 12 cools down, the tolerance band of the cylinder hole body mounting hole 12 is below the tolerance band of the cylinder hole body 3, the outer surface of the cylinder hole body 3 is pressed against the inner wall of the cylinder hole body mounting hole 12, and a tight contact is formed, thus forming an interference fit. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed together.

[0043] A shaft hole body mounting hole 13 is arranged in the middle of the plate structure of the crankcase base 1, and the extension line of the axis of the shaft hole body mounting hole 13 is perpendicular to the extension line of the axis of the cylinder hole body mounting hole 12 and is in the same plane.

[0044] The shaft hole body mounting hole 13 arranged on the crankcase base 1 is in a stepped hole structure, and the shaft hole body mounting hole 13 can be divided into an upper fitting hole section 131 and a lower fitting hole section 132, the diameter of the hole section of the upper fitting hole section 131 is greater than the diameter of the hole section of the lower fitting hole section 132. The upper fitting hole section 131 is above the lower fitting hole section 132.

[0045] The cylinder hole body 3 is a uniform thin-walled hollow tube structure as a whole, and a cylinder hole body oil groove 31 in an annular structure is arranged in the inner wall of the cylinder hole body 3. The cylinder hole body oil groove 31 can be arranged in the interior of the cylinder hole body 3. The cylinder hole body oil groove 31 cooperates with the piston 4 to lubricate the piston 4.

[0046] The shaft hole body 2 is a stepped shaft with a through hole structure arranged at the center position, and the outer wall of the shaft hole body 2 is respectively provided with an upper fitting shaft section 21 and a lower fitting shaft section 22 from top to bottom, and the diameter of the upper fitting shaft section 21 is greater than the diameter of the lower fitting shaft section 22.

[0047] The fitting and mounting mode between the shaft hole body 2 and the shaft hole body mounting hole 13 is also an interference fit, the upper fitting shaft section 21 and the upper fitting hole section 131 are interference fitted, and the lower fitting shaft section 22 and the lower fitting hole section 132 are interference fitted. The interference fit mode is described above, and thus is omitted here.

[0048] The outer wall of the cylinder hole body 3 is fixedly mounted with the crankcase base 1, and the inner wall of the cylinder hole body 3 is tightly fitted with the piston 4. The piston 4 can tightly adhere to the inner wall of the cylinder hole body 3 and slide along the axis of the cylinder hole body 3.

[0049] Example Two:

[0050] The structure of this embodiment is similar to that of Example One, and is further extended on the basis of Example One.

[0051] As shown in Figures 1 to 5 A split crankcase of a refrigeration compressor comprises a crankcase base 1 and a cylinder bore body 3 and a shaft bore body 2, the shaft bore body 2 is fixedly connected with the crankcase base 1 in the form of interference fit, and the cylinder bore body 3 is fixedly connected with the crankcase base 1.

[0052] The refrigeration compressor for refrigerator has a long history, and almost all the refrigeration compressor crankcases for refrigerator are integrally formed by casting, and the cast iron blanks need to be finally put into use through complex processes. Generally, after the crankcase casting is demolded, it needs to be processed by at least five large special equipment, and five sets of large special clamps are matched, including the processing of high-pressure cavity and screw hole, the processing of stator surface and cylinder surface, the processing of drain hole, the processing of outer bearing surface, and the honing processing of shaft hole and cylinder hole.

[0053] With the diversification of market demand and the increasingly fast updating speed of products, the types of crankcases are increasingly diversified, the crankcase processing equipment is special, and the crankcase itself is also one-to-one special for the compressor, so as to cause the sharp rise of equipment cost, processing cost and organization cost.

[0054] Part of the crankcases are split crankcases, but this part of the split crankcases is connected through screws, and the perpendicularity of the shaft hole and the cylinder hole on the crankcase, the coaxiality and the cylindricity of the shaft hole and the outer bearing hole are extremely high, and the requirements reach 50 microns, so the split crankcase connected through screws has too high requirements for the screw hole processing and assembly equipment of the split part and the base part, and the probability of unqualified products is relatively large in actual application.

[0055] Moreover, in the actual use of large-diameter cylinder holes, the existing large-diameter piston matching surface matched with the cylinder hole needs to be processed with an oil groove, and the number of oil grooves can be one or more. Due to the fixing through bolts, the inner cylindrical surface of the cylinder hole can not be a complete cylindrical surface, in order to ensure the cylindricity and other key form and position tolerances of the piston, the processing difficulty of the oil groove is relatively large.

[0056] In summary, the forming and processing of the crankcase of the refrigeration compressor for refrigerator are difficult, the whole process cost is high, the precision of the final part is difficult to guarantee, and different specifications are numerous and cannot be replaced, which brings many inconveniences to production, development and operation.

[0057] And in the embodiment provides a kind of split crankcase of refrigeration compressor, compared with traditional integrated crankcase, the utility model is split crankcase structure.On the one hand, the mold of the crankcase of the utility model is not the mold structure of traditional integrated crankcase complex.And after each part is made, the surface is more flat than integrated integrated crankcase, needs less processing, and does not need to process high-precision threaded hole for the fixed installation of crankcase base 1 and shaft hole body 2 and cylinder hole body 3 like existing split crankcase.Installation is more convenient.

[0058] The main body of the crankcase base 1 is a plate structure, and a cuboid cylinder hole body matching part 11 is arranged on the plate structure of the crankcase base 1, and a cylinder hole body mounting hole 12 is arranged at the middle position of the cuboid cylinder hole body matching part 11. The axis of the cylinder hole body mounting hole 12 is parallel to the surface of the plate structure of the crankcase base 1, and the inner cylindrical surface of the cylinder hole body mounting hole 12 is close to tangent to the upper surface of the plate structure of the crankcase base 1.

[0059] The cylinder hole body mounting hole 12 is a through hole structure, that is, the cylinder hole body mounting hole 12 is a through hole arranged in the cuboid cylinder hole body matching part 11. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed by interference fit, so as to fix the cylinder hole body 3 on the cylinder hole body mounting hole 12.

[0060] The interference fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 can use liquid nitrogen and other low-temperature substances to cool the cylinder hole body 3, so that the cylinder hole body 3 shrinks when cold, so that the tolerance band range of the cylinder hole body 3 above the tolerance band range of the cylinder hole body mounting hole 12 falls below the tolerance band range of the cylinder hole body mounting hole 12, so that the cylinder hole body 3 can be easily put into the cylinder hole body mounting hole 12, so as to fix and install the cylinder hole body 3 and the cylinder hole body mounting hole 12.

[0061] When the temperature of the cylinder hole body 3 returns to room temperature, the tolerance band range of the cylinder hole body 3 returns to above the tolerance band range of the cylinder hole body mounting hole 12 at this time, so that the outer surface of the cylinder hole body 3 is extruded and tightly contacted with the inner wall of the cylinder hole body mounting hole 12, forming interference fit. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed together.

[0062] Because the cylinder hole body 3 and the cylinder hole body mounting hole 12 are both complete cylindrical surface structures, not being damaged, the specific position or angle of the cooperation between the cylinder hole body 3 and the cylinder hole body mounting hole 12 does not need to be considered, and the cooperation between the cylinder hole body 3 and the cylinder hole body mounting hole 12 does not need to consider the hole shaft cooperation or other structure limitation cooperation, so the assembly is convenient.

[0063] The interference fit between the cylinder hole body 3 and the cylinder hole body mounting hole 12 can also select to heat the cylinder hole body mounting hole 12, so that the inner diameter of the cylinder hole body mounting hole 12 increases. Under the same or similar temperature conditions, the outer wall diameter of the cylinder hole body 3 is the same as that of the cylinder hole body mounting hole 12, but the tolerance band of the outer wall of the cylinder hole body 3 is above that of the cylinder hole body mounting hole 12.

[0064] Therefore, under normal circumstances, the cylinder hole body 3 cannot be put into the cylinder hole body mounting hole 12, so the cylinder hole body mounting hole 12 is heated, and after the hole diameter of the cylinder hole body mounting hole 12 is heated and expanded, the tolerance band of the cylinder hole body mounting hole 12 is above the tolerance band of the cylinder hole body 3, so that the cylinder hole body 3 can be put into the inside of the cylinder hole body mounting hole 12.

[0065] After the cylinder hole body mounting hole 12 cools down, the tolerance band of the cylinder hole body mounting hole 12 is below the tolerance band of the cylinder hole body 3, the outer surface of the cylinder hole body 3 is extruded with the inner wall of the cylinder hole body mounting hole 12, and the interference fit is formed. The cylinder hole body mounting hole 12 and the cylinder hole body 3 are firmly fixed together.

[0066] The shaft hole body mounting hole 13 is arranged in the middle of the plate-shaped structure of the crankcase base 1, and the extension line of the axis of the shaft hole body mounting hole 13 intersects perpendicularly with the extension line of the axis of the cylinder hole body mounting hole 12 on the same plane.

[0067] The shaft hole body mounting hole 13 arranged on the crankcase base 1 is in a stepped hole structure, and the shaft hole body mounting hole 13 can be divided into two interference fit sections, i.e., an upper fit hole section 131 and a lower fit hole section 132, and the diameter of the hole section of the upper fit hole section 131 is greater than that of the lower fit hole section 132. The upper fit hole section 131 is above the lower fit hole section 132.

[0068] The cylinder hole body 3 is a uniform thin-walled hollow tube structure as a whole, and a cylinder hole body oil groove 31 in an annular structure is arranged in the inner wall of the cylinder hole body 3. The cylinder hole body oil groove 31 can be arranged in the inside of the cylinder hole body 3. The cylinder hole body oil groove 31 cooperates with the piston 4 to lubricate the piston 4.

[0069] The shaft hole body 2 is a stepped shaft with a through hole structure in the center position. The outer wall of the shaft hole body 2 is respectively provided with an upper matching shaft section 21 and a lower matching shaft section 22 from top to bottom. The diameter of the upper matching shaft section 21 is larger than that of the lower matching shaft section 22.

[0070] The matching installation mode between the shaft hole body 2 and the shaft hole body mounting hole 13 is also interference fit. The upper matching shaft section 21 and the upper matching hole section 131 are interference fit, and the lower matching shaft section 22 and the lower matching hole section 132 are interference fit. The interference fit mode is described above, so it is omitted here.

[0071] The outer wall of the cylinder hole body 3 is fixedly installed with the crankcase base 1, and the inner wall of the cylinder hole body 3 is tightly matched with the piston 4. The piston 4 can tightly adhere to the inner wall of the cylinder hole body 3 and slide along the axis of the cylinder hole body 3.

[0072] The crankcase base 1, the shaft hole body 2 and the cylinder hole body 3 are castings.

Claims

1. A split crankcase for a refrigeration compressor, characterized in that, The application relates to a crankcase base (1) and a shaft hole body (2) and a cylinder hole body (3), the shaft hole body (2) is fixedly connected with the crankcase base (1), and the cylinder hole body (3) is fixedly connected with the crankcase base (1). The crankcase base (1) is provided with a shaft hole body mounting hole (13), the crankcase base (1) is provided with a cylinder hole body matching part (11), and the axis of the shaft hole body mounting hole (13) is perpendicular to the axis of a cylinder hole body mounting hole (12).

2. A split crankcase for a refrigerant compressor as set forth in claim 1 wherein, The cylinder hole body matching part (11) is located on one side of the crankcase base (1), and the cylinder hole body mounting hole (12) is located in the middle of the planar part of the crankcase base (1).

3. A split crankcase for a refrigerant compressor as set forth in claim 2 wherein, The cylinder hole body mounting hole (12) is a through hole, and the cylinder hole body mounting hole (12) is in interference fit with the cylinder hole body (3).

4. A split crankcase for a refrigerant compressor as set forth in claim 1 wherein, The cylinder hole body (3) is provided with a piston (4), the piston (4) is a stepped cylindrical structure, the outer diameter of both ends is equal to the inner diameter of the cylinder hole body (3), and the outer diameter of the middle part is smaller than that of both ends.

5. A split crankcase for a refrigerant compressor as claimed in claim 1 or 2 or 3 or 4, wherein, The shaft hole body mounting hole (13) provided on the crankcase base (1) is a stepped hole, the shaft hole body mounting hole (13) is provided with an upper matching hole section (131) and a lower matching hole section (132), and the diameter of the upper matching hole section (131) is larger than that of the lower matching hole section (132).

6. A split crankcase for a refrigerant compressor as defined in claim 1 or 2 or 3 or 4, characterized in that The cylinder hole body (3) is a thin-walled hollow tube structure, and the inner wall of the cylinder hole body (3) is provided with an annular cylinder hole body oil groove (31).

7. A split crankcase for a refrigerant compressor as set forth in claim 5 wherein, The shaft hole body (2) is a stepped shaft with a hole in the center, the outer wall of the shaft hole body (2) is respectively an upper matching shaft section (21) and a lower matching shaft section (22) from top to bottom, and the diameter of the upper matching shaft section (21) is larger than that of the lower matching shaft section (22).

8. A split crankcase for a refrigerant compressor as set forth in claim 7 wherein, The shaft hole body (2) is in interference fit with the shaft hole body mounting hole (13), the upper matching shaft section (21) is in interference fit with the upper matching hole section (131), and the lower matching shaft section (22) is in interference fit with the lower matching hole section (132).

9. A split crankcase for a refrigerant compressor as claimed in claim 1 or 2 or 3 or 4 or 7 or 8, characterized in that The outer wall of the cylinder hole body (3) is fixedly installed with the crankcase base (1), the cylinder hole body (3) is provided with a piston (4), and the inner wall of the cylinder hole body (3) is in close fit with the piston (4).

10. A split crankcase for a refrigerant compressor as defined in claim 1 or 2 or 3 or 4 or 7 or 8, characterized by The crankcase base (1), the shaft hole body (2) and the cylinder hole body (3) are castings.

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