CN104358703A - An Assembly Structure of Shaft and Rotor Suitable for Cold Assembly - Google Patents

Abstract

The invention discloses a shaft and rotor assembly structure suitable for cold assembly, which comprises a rotor and a shaft provided with a long shaft part, wherein the long shaft part is provided with a rotor mounting position, the rotor is sleeved on the rotor mounting position of the shaft, the outer edge of the long shaft part is provided with a cutting edge, the outer edge of the long shaft part is locally provided with a projection with a certain taper, and the axis of the long shaft part is hollowed out and screwed with a screw. According to the assembly structure of the shaft and the rotor, which is suitable for cold assembly, the improvement modes of physical structures such as trimming and conicity are added on the shaft, the hooping force of the shaft and the rotor after the shaft is rotationally assembled is increased, and the reliable assembly of the shaft and the rotor is realized.

Description

An Assembly Structure of Shaft and Rotor Suitable for Cold Assembly

technical field

The invention relates to the field of compressors, in particular to an assembly structure of a shaft and a rotor suitable for cold assembly. the

Background technique

In refrigeration compressors, the assembly of the shaft and the rotor is usually achieved by interference shrink fitting. The interference heat packing mainly utilizes the thermal expansion and contraction properties of the material. Put the thermally expanded rotor on the shaft. When the rotor recovers, it will generate a clamping force on the shaft to ensure the tight connection between the shaft and the rotor. The thermal charging method needs to heat the rotor. During the assembly process, the deformation of the rotor is large, which is prone to quality problems. Especially for some small machines, the thermal charging method often causes prominent quality problems due to its excessive deformation. the

Contents of the invention

In view of this, in order to solve the above technical problems, the present invention provides a shaft and rotor assembly structure suitable for cold assembly, adding trimming and taper on the shaft to improve the physical structure, and increasing the shaft and rotor after the transfer. The clamping force of the rotor realizes the reliable assembly of the shaft and the rotor. the

The purpose of the present invention is achieved through the following technical solutions:

An assembly structure of a shaft and a rotor suitable for cold assembly, comprising a shaft and a rotor provided with a long shaft portion, the long shaft portion is provided with a rotor mounting position, and the rotor is sleeved on the rotor mounting position of the shaft, It is characterized in that: the outer edge of the long axis is provided with trimming, the outer edge of the long axis is partially provided with a protrusion with a certain taper, and the axis of the long axis is hollowed out and screwed into it.

The edge trimming refers to the neat edge trimming of the long axis along the axial direction; the protrusion refers to the protrusion with a certain taper along the axial direction of the long axis. Due to the trimming and protrusions on the outer edge of the long shaft, the cross-section of the shaft changes from a regular circle to an irregular approximate circle, matching with the regular circle inside the rotor, and the inner diameter of the rotor is slightly smaller than the outer diameter of the shaft. Therefore, the shaft and the rotor have an interference fit, and the rotor is pushed into the rotor installation position by means of external pressure. Due to the interference between the shaft and the rotor, the rotor generates a clamping force on the shaft to achieve reliable assembly of the shaft and the rotor. The shaft center of the long shaft is hollowed out and screwed into the screw. Due to the extrusion of the screw thread, the axial outer side expands; after the rotor is installed on the shaft, the shaft expands radially by adding screws; without increasing the rotor On the premise of difficulty in press-fitting, the interference between the shaft and the rotor is increased. the

The protrusion can be arranged on the upper or lower part of the rotor installation position; the protrusion is arranged on the upper part of the rotor installation position, and the highest point of the protrusion is located at the end of the rotor installation position; the protrusion is arranged on the lower part of the rotor installation position, and the protrusion The highest point is located at the rotor installation position and the distance from the end is greater than 3mm. the

If the protrusion is arranged on the upper part of the rotor installation position, that is, at the rotor entrance of the rotor installation position, the highest point of the protrusion is located at the end of the rotor installation position, that is, at the entrance of one end of the shaft screwed into the rotor. At this time, the highest point of the protrusion and the inner diameter of the rotor squeeze each other to generate an active force, and the rotor is bound by the active force and is firmly locked on the rotor installation position. the

If the protrusion is arranged at the lower part of the rotor installation position, that is, at the end of the rotor installation position, the highest point of the protrusion must be set at a position more than 3mm away from the end of the rotor installation position. the

In addition, protrusions can be provided on both the upper and lower parts of the rotor installation site, and at this time the highest point of the lower protrusion can be located at the end of the rotor installation site. the

The cut edge includes the entire rotor mounting position and the region from the rotor mounting position to the end of the shaft. the

Due to the interference between the shaft and the rotor, in order to reduce the installation difficulty of the rotor, in addition to the trimming on the rotor mounting position, it is also necessary to set the trimming in the area between the end of the shaft and the rotor mounting position. the

The trimming is rectangular, and the width w of the trimming and the diameter r of the shaft satisfy the following relationship: (5/8)r≤w≤r. the

On a cross-sectional view of a shaft, the width of the cut edge is the chord on the cross-sectional view of the shaft. When the central angle corresponding to the chord is 60°, the width w is equal to the diameter r; when the central angle corresponding to the chord is 30°, the width w is equal to five-eighths of the diameter r. The main function of trimming is to partially reduce the interference between the shaft and the rotor, so that the interference fit between the shaft and the rotor can reach an ideal state. In addition, due to the existence of the cut edge, part of the outer surface of the shaft is an arc surface, and the other part is a flat surface, while the inner side of the rotor is an arc surface, which increases the force of the contact part between the shaft and the rotor at the cut edge, that is, the shaft and the rotor The rotor gets more clamping force. the

The inventor combined his own knowledge and found after many experiments and comparisons that when the number of cut edges is different, the corresponding length of the string needs to be adjusted to achieve the best effect. Considering that when the number of trimmings is greater than 3, the improvement of the clamping effect is not obvious, so the number of trimmings of 3 or less is used as the preferred mode. the

The number of the trimming is one, and the width w of the trimming and the diameter r of the shaft satisfy the following relationship: (3/4)r≤w≤r. the

The number of the trimmings is 2, the positions of the two trimmings are symmetrical about the axis, and the width w of the trimming and the diameter r of the shaft satisfy the following relationship: (5/8)r≤w≤(7 /8) r. the

The number of the trimmings is 3, the positions of the three trimmings form an angle of 120° with the axis, and the width w of the trimming and the diameter r of the shaft satisfy the following relationship: (5/8)r≤ w≤(3/4)r. the

The taper of the protrusion is 5°-10°, and the height is less than (1/5)r. the

The taper of the protrusions can be provided with multi-level tapers, starting from the highest point of the protrusions, there are first-level taper, second-level taper and so on. Wherein, in order to ensure that the contact surface of the rotor sleeved on the protrusion is more evenly stressed and reduce stress concentration, the size of the N-level taper must be smaller than the (N+1)-level taper, where N is a natural number. the

Description of drawings

The present invention will be further described by using the accompanying drawings, but the embodiments in the accompanying drawings do not constitute any limitation to the present invention.

Fig. 1 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 1 of the present invention. the

Fig. 2 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 1 of the present invention. the

Fig. 3 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 2 of the present invention. the

4 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 2 of the present invention. the

Fig. 5 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 3 of the present invention. the

Fig. 6 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 3 of the present invention. the

Fig. 7 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 4 of the present invention. the

Fig. 8 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 4 of the present invention. the

Fig. 9 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 5 of the present invention. the

Fig. 10 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 5 of the present invention. the

Fig. 11 is a schematic diagram of an assembly structure of a shaft and a rotor suitable for cold assembly according to Embodiment 6 of the present invention. the

Fig. 12 is a cross-sectional view of the shaft of the assembly structure of the shaft and the rotor suitable for cold assembly according to Embodiment 6 of the present invention. the

Detailed ways

In order to facilitate the understanding of those skilled in the art, the present invention will be further described in detail below with reference to the drawings and embodiments. the

Please refer to Fig. 1-2, embodiment 1 of the present invention comprises:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 11 with a long shaft and a rotor 12, the long shaft is provided with a rotor mounting position 13, and the rotor 12 is sleeved on the rotor mounting position 13 of the shaft 11 On the top, the outer edge of the long axis is provided with a trimming edge 14, and the outer edge of the long axis is partially provided with a protrusion 15 with a certain taper, and the axis 16 of the long axis is hollowed out and screwed with a screw 17.

The protrusion 15 is arranged on the upper part of the rotor installation position 13 , and the highest point of the protrusion 15 is located at the end of the rotor installation position 13 . the

The trim 14 includes the entire rotor mounting point 13 and the region from the rotor mounting point 13 to the end 18 of the shaft 11 . the

The trimming 14 is rectangular, and the number of the trimming 14 is one. The width w1 of the trimming 14 and the diameter r1 of the shaft 11 satisfy the following relationship: (3/4)r1≤w1≤r1. In this embodiment, the value of the diameter r1 is 16 mm, and the value of the width w1 is 13 mm. the

The taper of the protrusion 15 has only one degree of taper, the taper is 5°, and the protrusion height of the highest point of the protrusion 15 is 2.8mm. the

Beneficial effects of this embodiment 1: Compared with the traditional shrink-fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; the protrusion and single-cut with a taper of 5° placed at the lower part of the rotor installation position The edge ensures sufficient interference between the shaft and the rotor, and the assembled shaft and rotor have a better tightness. the

Please refer to Fig. 3-4, embodiment 2 of the present invention comprises:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 21 with a long shaft and a rotor 22, the long shaft is provided with a rotor mounting position 23, and the rotor 22 is sleeved on the rotor mounting position 23 of the shaft 21 On the top, the outer edge of the long axis is provided with trimming 24, and the outer edge of the long axis is partially provided with a protrusion 25 with a certain taper.

The protrusion 25 is arranged at the lower part of the rotor installation position 23, and the highest point of the protrusion 25 is located at the rotor installation position 23 and the distance from the end is 4mm. the

The cut edge 24 includes the entire rotor mounting location 23 and the region from the rotor mounting location 23 to the end 28 of the shaft. the

The trimming 24 is rectangular, the number of trimmings is 2, and the positions of the two trimmings are symmetrical about the axis. The width w2 of the trimming 24 and the diameter r2 of the shaft satisfy the following relationship: (5/8)r2≤w2≤( 7/8) r2. In this embodiment, the value of the diameter r2 is 14 mm, and the value of the width w2 is 10 mm. the

The taper of the protrusion 25 has only one degree of taper, the taper is 6°, and the protrusion height of the highest point of the protrusion 25 is 2.6 mm. the

Beneficial effects of this embodiment 2: Compared with the traditional shrink-fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; the protrusions with a taper of 6° and symmetrical distribution arranged at the lower part of the rotor installation position The double trimming on both sides of the shaft ensures sufficient interference between the shaft and the rotor, and the assembled shaft and rotor have a good tightness. the

Please refer to Fig. 5-6, embodiment 3 of the present invention comprises:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 31 with a long shaft and a rotor 32, the long shaft is provided with a rotor mounting position 33, and the rotor 32 is sleeved on the rotor mounting position 33 of the shaft 31 On the top, the outer edge of the long axis is provided with trimming 34 , and the outer edge of the long axis is partially provided with a protrusion with a certain taper, and the axis 36 of the long axis is hollowed out and screwed in with a screw 37 .

A protrusion 351 and a protrusion 352 are provided on the upper and lower parts of the rotor mounting position 33 , and the highest points of the two protrusions are located at the end of the rotor mounting position 33 . the

The cut edge 34 includes the entire rotor mounting location 33 and the region from the rotor mounting location 33 to the end 38 of the shaft 31 . the

The trimming 34 is rectangular, and the number of trimmings is 3. The positions of the three trimmings form an angle of 120° with the axis. The width w3 of the trimming 34 and the diameter r3 of the shaft 31 satisfy the following relationship: (5/8) r3≤w3≤(3/4)r3. In this embodiment, the value of the diameter r3 is 16 mm, and the value of the width w3 is 12 mm. the

The taper of the protrusion is provided with a secondary taper, wherein the primary taper is 3°, the secondary taper is 7°, and the protrusion height of the highest point of the protrusion is 2.9mm. the

Beneficial effects of this embodiment 3: Compared with the traditional shrink-fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; the two protrusions arranged on the upper and lower parts of the rotor installation position and symmetrically distributed in the The three trimmings on the outer edge of the shaft, among which the protrusion is provided with a secondary taper, the primary taper is 3°, and the secondary taper is 7°, which ensures sufficient interference between the shaft and the rotor, and the tightness of the assembled shaft and rotor better. the

Please refer to Fig. 7-8, embodiment 4 of the present invention includes:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 41 with a long shaft and a rotor 42, the long shaft is provided with a rotor mounting position 43, and the rotor 42 is sleeved on the rotor mounting position 43 of the shaft 41 On the top, the outer edge of the long axis is provided with a trimming 44 , and the outer edge of the long axis is partially provided with a protrusion 45 with a certain taper, and the axis 46 of the long axis is hollowed out and screwed with a screw 47 .

The protrusion 45 is arranged on the upper part of the rotor installation position 43, and the highest point of the protrusion 45 is located at the end of the rotor installation position 43;

The cut edge 44 includes the entire rotor mounting position 43 and the region from the rotor mounting position 43 to the end 48 of the shaft 41 .

The trimming 44 is rectangular, the number of trimmings is 2, and the positions of the two trimmings are symmetrical about the axis. The width w4 of the trimming and the diameter r4 of the shaft satisfy the following relationship: (5/8)r4≤w4≤(7 /8) r4. In this embodiment, the value of the diameter r4 is 16 mm, and the value of the width w4 is 12 mm. the

The taper of the protrusion 45 is provided with a secondary taper, wherein the primary taper is 3°, the secondary taper is 8°, and the protrusion height of the highest point of the protrusion 45 is 3mm. the

Beneficial effects of this embodiment 4: Compared with the traditional shrink fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; the protrusions arranged on the upper part of the rotor installation position and the symmetrically distributed Double trimming, in which the protrusion is provided with a secondary taper, the primary taper is 3°, and the secondary taper is 8°, which ensures sufficient interference between the shaft and the rotor, and the assembled shaft and rotor have a better clamping degree. the

Please refer to Figures 9-10, Embodiment 5 of the present invention includes:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 51 with a long shaft and a rotor 52, the long shaft is provided with a rotor mounting position 53, and the rotor 52 is sleeved on the rotor mounting position 53 of the shaft 51 On the top, the outer edge of the long axis is provided with a trimming 54 , and the outer edge of the long axis is partially provided with a protrusion 55 with a certain taper, and the axis 56 of the long axis is hollowed out and screwed with a screw 57 .

The protrusion 55 is disposed on the upper part of the rotor installation position 53 , and the highest point of the protrusion 55 is located at the end of the rotor installation position 53 . the

The cut edge 54 includes the entire rotor mounting position 53 and the region from the rotor mounting position 53 to the end 58 of the shaft 51 . the

The trimming 54 is rectangular, and the number of trimmings is 3. The positions of the three trimmings form an angle of 120° with the axis. The width w5 of the trimming and the diameter r5 of the shaft satisfy the following relationship: (5/8)r5≤ w5≤(3/4)r5. In this embodiment, the value of the diameter r5 is 14 mm, and the value of the width w5 is 9 mm. the

The taper of the protrusion 55 is only one degree of taper, the taper is 6°, and the protrusion height of the highest point of the protrusion 55 is 2.5mm. the

Beneficial effects of this embodiment 5: Compared with the traditional shrink-fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; the protrusions with a taper of 6° and symmetrical distribution arranged on the upper part of the rotor installation position The three cut edges on the outer edge of the shaft ensure sufficient interference between the shaft and the rotor, and the assembled shaft and rotor have a better tightness. the

Please refer to Figures 11-12, Embodiment 6 of the present invention includes:

An assembly structure of a shaft and a rotor suitable for cold assembly, including a shaft 61 with a long shaft and a rotor 62, the long shaft is provided with a rotor mounting position 63, and the rotor 62 is sleeved on the rotor mounting position 63 of the shaft 61 On the top, the outer edge of the long axis is provided with a trimming 64 , and the outer edge of the long axis is partially provided with a protrusion 65 with a certain taper, and the axis 66 of the long axis is hollowed out and screwed with a screw 67 .

The protrusion 65 is arranged at the lower part of the rotor installation position 63 , the highest point of the protrusion 65 is located at the rotor installation position 63 and the distance from the end is greater than 3mm. the

The cut edge 64 includes the entire rotor mounting location and the region from the rotor mounting location 63 to the end 68 of the shaft 61 . the

The trimming 64 is rectangular, and the number of the trimming 64 is one. The width w6 of the trimming 64 and the diameter r6 of the shaft 61 satisfy the following relationship: (3/4)r6≤w6≤r6. In this embodiment, the value of the diameter r6 is 16 mm, and the value of the width w6 is 14 mm. the

The taper of the protrusion 65 has only one degree of taper, the taper is 7°, and the protrusion height of the highest point of the protrusion 65 is 2.9mm. the

Beneficial effects of this embodiment 6: Compared with the traditional shrink-fitting, the assembly of the present invention does not require heating, and the quality of the rotor can be better guaranteed; The single cut edge on the outer edge of the shaft ensures sufficient interference between the shaft and the rotor, and the assembled shaft and rotor have a good tightness. the

Finally, it should be noted that the above examples illustrate the technical solutions of the present invention, rather than limiting the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the present invention can be The technical solution of the invention shall be modified or equivalently replaced without departing from the spirit and scope of the technical solution of the present invention. the

Claims (8)

1. An assembly structure of a shaft and a rotor suitable for cold assembly, including a rotor and a shaft with a long shaft portion, the long shaft portion is provided with a rotor installation position, and the rotor is sleeved on the rotor installation position of the shaft Above, it is characterized in that: the outer edge of the long axis is provided with trimming, the outer edge of the long axis is partially provided with a protrusion with a certain taper, and the axis of the long axis is hollowed out and screwed into it. 2. The assembly structure of shaft and rotor suitable for cold assembly according to claim 1, characterized in that: the protrusion can be arranged on the upper or lower part of the rotor installation position; the protrusion is arranged on the upper part of the rotor installation position , the highest point of the protrusion is located at the end of the rotor installation position; the protrusion is arranged at the lower part of the rotor installation position, the highest point of the protrusion is located at the rotor installation position and the distance from the end is greater than 3mm. 3 . The assembly structure of a shaft and a rotor suitable for cold assembly according to claim 1 , wherein the cut edge includes the entire rotor mounting position and the area from the rotor mounting position to the end of the shaft. 4 . 4. The assembly structure of shaft and rotor suitable for cold assembly according to claim 1, characterized in that: the trimming is rectangular, and the width w of the trimming and the diameter r of the shaft satisfy the following relationship: ( 5/8) r≤w≤r. 5. The assembly structure of shaft and rotor suitable for cold assembly according to claim 4, characterized in that: the number of the trimmed edge is one, and the width w of the trimmed edge and the diameter r of the shaft satisfy The following relationship: (3/4)r≤w≤r. 6. The assembly structure of a shaft and a rotor suitable for cold assembly according to claim 4, characterized in that: the number of the cut edges is 2, and the positions of the two cut edges are symmetrical about the axis, so The width w of the cut edge and the diameter r of the shaft satisfy the following relationship: (5/8)r≤w≤(7/8)r. 7. The assembly structure of the shaft and the rotor suitable for cold assembly according to claim 4, characterized in that: the number of the trimming is 3, and the positions of the three trimmings are 120° from the axis The included angle, the width w of the trimmed side and the diameter r of the shaft satisfy the following relationship: (5/8)r≤w≤(3/4)r. 8. The assembly structure of shaft and rotor suitable for cold assembly according to claim 2, characterized in that: the taper of the protrusion is 5°-10°, and the height is less than (1/5)r.