CN212371555U - Knurling device for motor shaft - Google Patents

Abstract

The utility model belongs to the technical field of motor shaft production equipment, and relates to a motor shaft knurling device, which comprises a first base frame, wherein a first knurling seat and a second knurling seat are oppositely arranged on the first base frame, knurling shafts are respectively arranged on the first knurling seat and the second knurling seat, knurling knives are respectively arranged on the knurling shafts, a motor linear rail is arranged on the first knurling seat, a clamping mechanism for fixing a motor shaft is arranged on the motor linear rail, a fitting shaft is arranged on the second knurling seat, two taking arms are fixedly arranged on the fitting shaft, a case is arranged on the first base frame, a first stepping motor and a second stepping motor are arranged in the case, the first stepping motor is in transmission connection with the knurling shafts, the second stepping motor is in transmission connection with the fitting shaft, a feeding mechanism and a material taking mechanism are arranged below the first base frame, and are used for solving the problem that knurling is carried out when knurling is carried out on the motor shaft at present, the workpiece is loaded and unloaded by manpower, so that the labor cost is high, the working efficiency is low, and the labor intensity of workers is high.

Description

Knurling device for motor shaft

Technical Field

The utility model belongs to the technical field of motor shaft production facility, concretely relates to motor shaft annular knurl device.

Background

An electric machine (commonly called "motor") refers to an electromagnetic device for converting or transmitting electric energy according to the law of electromagnetic induction, and a motor shaft is an important part, and the performance of the motor shaft directly affects the performance of the whole electric machine and is a main driving part in modern industrial systems. The high-torque shaft can bear larger load capacity, the high-torque shaft is in inverse proportion to the rotating speed of the motor under the condition of fixed power, the faster the rotating speed of the motor is, the smaller the torque is, the slower the rotating speed of the motor is, the larger the torque is, the load capacity of the motor in a certain range is reflected, the common shaft body is cylindrical in design, the outer peripheral surface of the common shaft body is provided with more smooth surfaces to reduce abrasion, but when the high-torque shaft bears larger load, the friction of the smooth surfaces is smaller, and the common shaft body is easy to slip, so that the. For solving above-mentioned problem, many motor shaft surfaces carry out the annular knurl processing when the processing production of motor shaft, at present, when carrying out annular knurl processing to the motor shaft, because the structural constraint of annular knurl equipment, load and get a piece through manpower more, lead to the human cost high, work efficiency is low, and workman intensity of labour is great simultaneously.

SUMMERY OF THE UTILITY MODEL

To the problem mentioned in the background art, the utility model aims at: the motor shaft knurling device is used for solving the problems that when knurling is conducted on a motor shaft at present, due to the structural limitation of knurling equipment, a workpiece is assembled and taken through manpower, the labor cost is high, the working efficiency is low, and the labor intensity of workers is high.

In order to realize the technical purpose, the utility model discloses a technical scheme as follows:

a knurling device for a motor shaft comprises a control center and a knurling machine, wherein the knurling machine comprises a first base frame, a first knurling seat and a second knurling seat are oppositely arranged on the first base frame, knurling shafts are respectively arranged on the first knurling seat and the second knurling seat, knurling knives are respectively arranged on the knurling shafts, a motor linear rail is arranged on the first knurling seat, a clamping mechanism used for fixing the motor shaft is arranged on the motor linear rail, a fitting shaft is arranged on the second knurling seat, two fitting taking arms are fixedly arranged on the fitting shaft, the motor shaft is transferred through the two fitting taking arms, the deflection of the motor shaft in the transferring process can be avoided, a first clamping jaw is arranged at the end part of each fitting taking arm, a case is arranged on the first base frame, a first stepping motor and a second stepping motor are arranged in the case, and the first stepping motor is in transmission connection with the knurling shafts, the knurling tool is characterized in that a knurling shaft is driven to rotate through a first stepping motor, so that a knurling tool is driven to rotate, a second stepping motor is in transmission connection with a fitting shaft, the fitting shaft is driven to rotate through the second stepping motor, power is provided for rotation of the fitting shaft, meanwhile, the rotation angle of a taking arm is controllable, the collision of the motor shaft with the tool is avoided, a feeding mechanism and a taking mechanism are installed below a first base frame, a motor linear rail, a clamping mechanism, the first stepping motor, the second stepping motor, the feeding mechanism and the taking mechanism are all in control connection with a control center, the control center takes a PLC (programmable logic controller) as a core, and the running time, the running sequence and the working gap time of the motor linear rail, the clamping mechanism, the first stepping motor, the second stepping motor, the feeding mechanism and the taking mechanism which are all in control connection with the control center are controlled.

In the technical scheme, the utility model discloses still make following improvement:

further, the motor linear rail comprises a slide rail, a sliding table, a screw rod and a third step motor, the screw rod is installed on the slide rail, the sliding table is installed in the slide rail in a sliding mode, the sliding table is sleeved on the screw rod and is in threaded connection with the screw rod, the screw rod is in transmission connection with the third step motor, the clamping mechanism comprises a U-shaped clamping frame, the U-shaped clamping frame is installed on the sliding table, air cylinders are installed at two ends of the U-shaped clamping frame, and top cones are installed on air cylinder shafts of the air cylinders. The cylinder drives the tip cone to move, so that the motor shaft can be axially fixed, and the motor shaft can be rotated by fixing the two ends of the motor shaft of the tip cone top column simultaneously, so that knurling can be performed by a better matched knurling tool.

Further, the outside cover of cylinder is equipped with the safety cover. The cylinder can be protected by the protective cover.

Furthermore, the middle part of the piece taking arm is of an arc structure corresponding to the knurling shaft. Due to the structural design, the collision of the part taking arm with the knurling shaft in the rotating process can be avoided.

Further, feeding mechanism includes the second bed frame, install fourth step motor on the second bed frame, install first roller and second roller on the second bed frame, install two first conveyer belts between first roller and the second roller, the one end of second bed frame is installed two and is treated the work or material rest, two of setting relatively treat to install the third roller between the work or material rest, around being equipped with two feeding zones, two between second roller and the third roller the feeding zone is located between two first conveyer belts, the equidistant fixed mounting of surface on the feeding zone has a plurality of material supporting trip, it has the support to treat that the mounting bracket has on the work or material rest, install infrared inductor on the support, fourth step motor and infrared inductor all are connected with control center. The motor shaft to be processed is conveyed to one end of the feeding belt through the first conveying belt, the motor shaft is conveyed upwards along the feeding belt through the material supporting clamping hook when the feeding belt moves, the workpiece in-place detection can be carried out through the infrared sensor, and when the motor shaft moves to the position of the infrared sensor, the control center controls the fourth stepping motor to stop to operate to wait for the workpiece taking arm to take the workpiece.

Further, the guide plates are mounted on two sides of the second base frame. The position of the motor shaft can be adjusted through the limit of the guide plate, so that the motor shaft can be better matched with the clamping mechanism.

Further, the material taking mechanism comprises a third base frame, a fifth stepping motor and two fourth roller shafts are installed on the third base frame, the fifth stepping motor is in transmission connection with any one of the fourth roller shafts, the fifth stepping motor is in transmission connection with two second conveying belts around the fourth roller shafts, a connecting frame is installed on the third base frame, a sleeve is fixedly installed on the connecting frame, a lifting rod penetrates through the sleeve, a second clamping jaw is installed at the top end of the lifting rod, a notch is axially formed in the circumference of the lifting rod, transmission teeth are formed in the notch of the lifting rod, a sixth stepping motor is installed on the third base frame, a transmission gear is installed on an output shaft of the sixth stepping motor, the transmission gear is meshed with the transmission teeth on the lifting rod, and the fifth stepping motor and the sixth stepping motor are both connected with the control center. The fifth stepping motor drives the second conveying belt to move, the sixth stepping motor can drive the lifting rod to move so as to drive the second clamping jaw to lift and take the motor shaft with the knurled finish, when the second clamping jaw completely descends on the lower portion of the second conveying belt, the taken motor shaft automatically falls on the second conveying belt, and the second conveying belt turns away the machined workpiece.

Furthermore, grooves are uniformly formed in the second conveying belt. When the second conveyer belt moves, a motor shaft on the second conveyer belt can automatically roll into the groove, so that the motor shaft is prevented from continuously rolling on the second conveyer belt.

The utility model has the advantages that:

1. can carry the motor shaft that needs annular knurl to handle through feeding mechanism, the second step motor drives a dress axle and rotates and can shift the motor shaft of treating processing on the feeding mechanism to between two knurling cutters, can accomplish the fixed to the work piece through fixture, because fixture installs on motor linear rail, drive fixture and motor shaft work piece through motor linear rail and remove and can accomplish the annular knurl to the motor shaft, the motor shaft work piece of accomplishing is processed to last removable through taking mechanism, the operating duration of the drive part of each part through control center control, the automatic annular knurl processing of motor shaft can be accomplished to operation order and working gap time, be favorable to practicing thrift the human cost, and the production efficiency is improved, and the work burden of staff is lightened.

Drawings

The present invention can be further illustrated by the non-limiting examples given in the accompanying drawings;

fig. 1 is a schematic structural view of a knurling device of a motor shaft according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a knurling machine in an embodiment of a knurling device for a motor shaft of the present invention;

fig. 3 is a schematic structural view of a motor linear rail and a clamping mechanism in an embodiment of the present invention;

fig. 4 is a schematic structural view of a feeding mechanism in an embodiment of the present invention;

fig. 5 is a schematic view of a longitudinal structure of a feeding mechanism in an embodiment of the present invention;

fig. 6 is a schematic structural view of a material taking mechanism in an embodiment of the present invention;

FIG. 7 is a schematic view of the structure of the pick-up arm for picking up a work piece from the feeding belt according to the embodiment of the present invention;

fig. 8 is a first schematic view of the structure state of the clamping mechanism during clamping according to the embodiment of the present invention;

fig. 9 is a schematic view of a second structural state of the clamping mechanism during clamping according to the embodiment of the present invention;

fig. 10 is a schematic structural view of the pickup mechanism for picking up the parts according to the embodiment of the present invention;

fig. 11 is a schematic structural view of the pickup mechanism after the pickup is completed in the embodiment of the present invention;

the main element symbols are as follows:

the device comprises a first base frame 11, a first knurling base 12, a second knurling base 13, a knurling shaft 14, a loading shaft 16, a workpiece taking arm 17, a first claw 172, a case 18, a clamping mechanism 2, a sliding rail 21, a sliding table 23, a screw rod 25, a third stepping motor 26, a U-shaped clamping frame 27, a cylinder 281, a protective cover 282, a feeding mechanism 3, a second base frame 31, a first roller shaft 321, a second roller shaft 322, a third roller shaft 323, a feeding belt 34, a support 351, an infrared inductor 35, a guide plate 37, a four stepping motor 38, a workpiece waiting frame 39, a material taking mechanism 4, a third base frame 41, a fourth roller shaft 42, a second conveying belt 43, a connecting frame 44, a sleeve 45, a lifting rod 46, a transmission gear 461, a sixth stepping motor 47, a transmission gear 471 and a motor shaft 5.

Detailed Description

In order to make the present invention better understood by those skilled in the art, the technical solutions of the present invention are further described below with reference to the accompanying drawings and examples.

Examples

As shown in fig. 1-2, a knurling device for a motor shaft comprises a control center and a knurling machine, wherein the knurling machine comprises a first base frame 11, a first knurling base 12 and a second knurling base 13 are relatively installed on the first base frame 11, knurling shafts 14 are installed on the first knurling base 12 and the second knurling base 13, knurling cutters 15 are installed on the knurling shafts 14, a motor linear rail is installed on the first knurling base 12, a clamping mechanism 2 for fixing the motor shaft 5 is installed on the motor linear rail, a fitting shaft 16 is installed on the second knurling base 13, two fitting taking arms 17 are fixedly installed on the fitting shaft 16, the motor shaft 5 is transferred through the two fitting arms 17, and the deflection of the motor shaft 5 in the transferring process can be avoided. A first claw 172 is arranged at the end part of the workpiece taking arm 17, a case 18 is arranged on the first base frame 11, a first stepping motor and a second stepping motor are arranged in the case 18, the first stepping motor is in transmission connection with the knurling shaft 14, the knurling shaft 14 is driven to rotate by the first stepping motor so as to drive the knurling cutter 15 to rotate, the second stepping motor is in transmission connection with the assembling shaft 16, the assembling shaft 16 is driven to rotate by the second stepping motor so as to provide power for the rotation of the assembling shaft 16, meanwhile, the rotating angle of the workpiece taking arm 17 is controllable so as to prevent the motor shaft 5 from colliding with the cutter, a feeding mechanism 3 and a material taking mechanism 4 are arranged below the first base frame 11, a motor linear rail, a clamping mechanism 2, the first stepping motor, the second stepping motor, the feeding mechanism 3 and the material taking mechanism 4 are all in control connection with a control center, wherein the control center takes a PLC (programmable logic controller) as a core, and the motor linear rail, the clamping mechanism, The clamping mechanism 2, the first stepping motor, the second stepping motor, the feeding mechanism 3 and the material taking mechanism 4 are all controlled by the control center to control the running time, the running sequence and the working clearance time.

Specifically, as shown in fig. 3 and 10, the motor linear rail includes a slide rail 21, a sliding table 23, a screw rod 25 and a third step motor 26, the screw rod 25 is installed on the slide rail 21, the sliding table 23 is installed in the slide rail 21 in a sliding manner, the sliding table 23 is sleeved on the screw rod 25 and is in threaded connection with the screw rod 25, and the screw rod 25 is in transmission connection with the third step motor 26. The clamping mechanism 2 comprises a U-shaped clamping frame 27, the U-shaped clamping frame 27 is installed on the sliding table 23, air cylinders 281 are installed at two ends of the U-shaped clamping frame 27, and tip cones 29 are installed on air cylinder shafts of the air cylinders 281. Drive the apical cone 29 through the cylinder 281 and remove, can carry out axial fixity to motor shaft 5, fix through the both ends of the apical cone 29 apical post motor shaft 5 simultaneously and still make motor shaft 5 rotatable to cooperation knurling sword 15 that can be better carries out the annular knurl, and wherein, the outside cover of cylinder 281 is equipped with safety cover 282, can protect cylinder 281 through safety cover 282.

Specifically, as shown in fig. 7, the middle of the pick arm 17 is of an arc-shaped configuration corresponding to the knurling shaft 14. Due to the structural design, the part taking arm 17 can be prevented from colliding with the knurling shaft 14 in the rotating process.

Specifically, as shown in fig. 4 and 5, the feeding mechanism 3 includes a second base frame 31 and a first conveyor belt 33, a fourth stepping motor 38 is installed on the second base frame 31, a first roller 321 and a second roller 322 are installed on the second base frame 31, two first conveyor belts 33 are installed between the first roller 321 and the second roller 322, two opposite material waiting frames 39 are installed at one end of the second base frame 31, a third roller 323 is installed between the two material waiting frames 39, two feed belts 34 are wound between the second roller 322 and the third roller 323, the two feed belts 34 are located between the two first conveyor belts 33, a plurality of material supporting hooks 341 are fixedly installed on the outer surface of the feed belt 34 at equal intervals, a support 351 is installed on the material waiting frame 39, an infrared inductor 35 is installed on the support 351, and the fourth stepping motor 38 and the infrared inductor 35 are both connected to the control center. Motor shaft 5 that will treat processing is carried to feed zone 34 one end through first conveyer belt 33, feed zone 34 moves the time through holding in the palm material trip 341 with motor shaft 5 along feed zone 34 upwards transport, can carry out the work piece through infrared inductor 35 and detect that targets in place, when motor shaft 5 removed to infrared inductor 35 position, control center control fourth step motor 38 stall waiting to get an arm 17 and get a piece, wherein, deflector 37 is all installed to the both sides of second bed frame 31, spacing through deflector 37 can be adjusted motor shaft 5 position, make the better cooperation fixture 2 of motor shaft 5 ability.

Specifically, as shown in fig. 6, the material taking mechanism 4 includes a third base frame 41, a fifth stepping motor 49 and two fourth roller shafts 42 are mounted on the third base frame 41, the fifth stepping motor 49 is connected with any one of the fourth roller shafts 42 in a transmission manner, two second conveyor belts 43 are wound on the two fourth roller shafts 42, a connecting frame 44 is mounted on the third base frame 41, a sleeve 45 is fixedly mounted on the connecting frame 44, a lifting rod 46 penetrates through the sleeve 45, a second claw 48 is mounted at the top end of the lifting rod 46, a gap is axially formed on the circumference of the lifting rod 46, a transmission tooth 461 is formed in the gap of the lifting rod 46, a sixth stepping motor 47 is mounted on the third base frame 41, a transmission gear 471 is mounted on an output shaft of the sixth stepping motor 47, the transmission gear is engaged with the transmission tooth 461 on the lifting rod 46, both the fifth stepping motor 49 and the sixth stepping motor 47 are connected with a control center, the second conveyor belt 43 is uniformly provided with grooves 431. Drive the second conveyer belt 43 through fifth step motor 49 and remove, thereby sixth step motor 47 can drive lifter 46 and remove and thereby drive second jack catch 48 and go up and down to get the piece to motor shaft 5 that the annular knurl was accomplished, when second jack catch 48 descends in second conveyer belt 43 lower part completely, motor shaft 5 that takes off is from walking on second conveyer belt 43, the work piece of processing completion is walked away by second conveyer belt 43, when the design of recess 431 can make second conveyer belt 43 remove, motor shaft 5 on the second conveyer belt 43 can roll into in the recess 431 by oneself, avoid motor shaft 5 to last the rolling on second conveyer belt 43.

When the motor shaft processing device is used, the motor shaft 5 to be processed is placed on the first conveying belt 33, the fourth stepping motor 38 drives the first roller shaft 321 to rotate under the control of the control center to drive the first conveying belt 33 to move, and the second rotating shaft 322 synchronously rotates under the transmission action of the first conveying belt 33 and drives the feeding belt 34 to rotate. When the motor shaft on the first conveyor belt 33 moves to the position of the feed belt 34, because the feed belt 34 is obliquely arranged, the motor shaft 5 cannot move continuously, while the feed belt 34 can lift the motor shaft 5 at the end part to move along the feed belt 34 through the material supporting clamping hook 341 when rotating, when the motor shaft 5 moves to the position of the infrared sensor 35 (as shown in fig. 4), the infrared sensor 35 feeds back a workpiece in-place signal to the control center, the control center controls the fourth stepping motor 38 to stop working, and simultaneously controls the second stepping motor to work to drive the part mounting shaft 16 to rotate to drive the part taking arm 17 to rotate for a fixed angle, the first clamping jaw 172 of the part taking arm 17 takes the motor shaft 5 at the position of the infrared sensor 35 from the feed belt 34 (as shown in fig. 7), after the rotation of the part taking arm 17 is finished, the motor shaft 5 on the first clamping jaw 172 is positioned between the two air cylinders 281, and the control center air cylinder 281 starts to clamp the motor shaft 5 through, As shown in fig. 9), and the pick arm 17 returns to wait for the next pick. After the motor shaft 5 is clamped by the air cylinder 281, the control center controls the third stepping motor 26 and the first stepping motor to start, the third stepping motor 26 drives the screw rod 25 to rotate to drive the sliding table 23 to move for a preset distance, and the sliding table 23 moves to drive the U-shaped clamping frame 27 and the fixed motor shaft 5 to synchronously move to finish knurling. After knurling is finished, the sliding table 23 drives the U-shaped clamping frame 27 and the fixed motor shaft 5 to move above the material taking mechanism 4, at this time, the control center controls the fifth stepping motor 49 and the sixth stepping motor 47 to work, the fifth stepping motor 49 drives the second conveying belt 43 to move, and the sixth stepping motor 47 drives the lifting rod 46 to ascend by a preset height, so that the second clamping jaw 48 clamps the motor shaft 5 (as shown in fig. 10); then, the sixth stepping motor 47 rotates to drive the lifting rod 46 to descend, so that the second clamping jaw 48 descends by a preset height, at this time, the second clamping jaw 48 is located at the lower part of the second conveying belt 43, the motor shaft 5 on the second clamping jaw 48 falls on the second conveying belt 43, and the fourth stepping motor 38 is started again after single knurling, and the next knurling is performed according to the steps.

It is right above the utility model provides a pair of motor shaft annular knurl device introduces in detail. The description of the specific embodiments is only intended to facilitate an understanding of the method of the invention and its core ideas. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims (8)

1. The utility model provides a motor shaft knurling device, includes control center and knurling machine, its characterized in that: the knurling machine comprises a first base frame (11), wherein a first knurling seat (12) and a second knurling seat (13) are relatively installed on the first base frame (11), knurling shafts (14) are installed on the first knurling seat (12) and the second knurling seat (13), knurling cutters (15) are installed on the knurling shafts (14), a motor linear rail is installed on the first knurling seat (12), a clamping mechanism (2) used for fixing a motor shaft (5) is installed on the motor linear rail, a mounting shaft (16) is installed on the second knurling seat (13), two workpiece taking arms (17) are fixedly installed on the mounting shaft (16), a first clamping jaw (172) is installed at the end part of each workpiece taking arm (17), a machine case (18) is installed on the first base frame (11), and a first stepping motor and a second stepping motor are installed in the machine case (18), the first stepping motor is in transmission connection with the knurling shaft (14), the second stepping motor is in transmission connection with the fitting shaft (16), the feeding mechanism (3) and the material taking mechanism (4) are installed below the first base frame (11), and the motor linear rail, the clamping mechanism (2), the first stepping motor, the second stepping motor, the feeding mechanism (3) and the material taking mechanism (4) are all in control connection with the control center.

2. The knurling device of a motor shaft of claim 1, wherein: the motor linear rail comprises a sliding rail (21), a sliding table (23), a screw rod (25) and a third step motor (26), the screw rod (25) is installed on the sliding rail (21), the sliding table (23) is installed in the sliding rail (21) in a sliding mode, the sliding table (23) is sleeved on the screw rod (25) and is in threaded connection with the screw rod (25), the screw rod (25) is in transmission connection with the third step motor (26), the clamping mechanism (2) comprises a U-shaped clamping frame (27), the U-shaped clamping frame (27) is installed on the sliding table (23), air cylinders (281) are installed at two ends of the U-shaped clamping frame (27), and top cones (29) are installed on air cylinder shafts of the air cylinders (281).

3. The knurling device of a motor shaft of claim 2, wherein: the outer cover of the air cylinder (281) is provided with a protective cover (282).

4. The knurling device of a motor shaft of claim 1, wherein: the middle part of the piece taking arm (17) is of an arc structure corresponding to the knurling shaft (14).

5. The knurling device of a motor shaft of claim 1, wherein: the feeding mechanism (3) comprises a second base frame (31), a fourth stepping motor (38) is installed on the second base frame (31), a first roller shaft (321) and a second roller shaft (322) are installed on the second base frame (31), two first conveying belts (33) are installed between the first roller shaft (321) and the second roller shaft (322), two material waiting frames (39) which are oppositely arranged are installed at one end of the second base frame (31), a third roller shaft (323) is installed between the two material waiting frames (39), two feeding belts (34) are wound between the second roller shaft (322) and the third roller shaft (323), the two feeding belts (34) are located between the two first conveying belts (33), a plurality of material supporting clamping hooks (341) are fixedly installed on the outer surface of each feeding belt (34) at equal intervals, a support (351) is installed on each material waiting frame (39), install infrared inductor (35) on support (351), fourth step motor (38) and infrared inductor (35) all are connected with control center.

6. The knurling device of a motor shaft of claim 5, wherein: and guide plates (37) are arranged on two sides of the second base frame (31).

7. The knurling device of a motor shaft of claim 1, wherein: the material taking mechanism (4) comprises a third base frame (41), a fifth stepping motor (49) and two fourth roller shafts (42) are installed on the third base frame (41), the fifth stepping motor (49) is in transmission connection with any one of the fourth roller shafts (42), two second conveying belts (43) are wound on the two fourth roller shafts (42), a connecting frame (44) is installed on the third base frame (41), a sleeve (45) is fixedly installed on the connecting frame (44), a lifting rod (46) penetrates through the sleeve (45), a second claw (48) is installed at the top end of the lifting rod (46), a notch is axially formed in the circumference of the lifting rod (46), a transmission tooth (461) is formed in the notch of the lifting rod (46), a sixth stepping motor (47) is installed on the third base frame (41), and a transmission gear (471) is installed on an output shaft of the sixth stepping motor (47), the transmission gear (471) is meshed with transmission teeth (461) on the lifting rod (46), and the fifth stepping motor (49) and the sixth stepping motor (47) are both connected with the control center.

8. The knurling device of a motor shaft of claim 7, wherein: the second conveying belt (43) is uniformly provided with grooves (431).

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