CN112018930A

CN112018930A - Motor, motor actuator provided with same, and packaging pallet for conveyance

Info

Publication number: CN112018930A
Application number: CN202010423201.8A
Authority: CN
Inventors: 小柳尚久; 仓惠子; 佐野孝广; 高久幸也
Original assignee: Tokyo Parts Ind Co Ltd
Current assignee: Tokyo Parts Ind Co Ltd
Priority date: 2019-05-28
Filing date: 2020-05-19
Publication date: 2020-12-01

Abstract

The invention provides a motor which does not need to be wound by a lead wire during assembly and prevents unnecessary rotation of the motor during assembly so as to easily realize automatic assembly, a motor actuator using the motor and a packing tray for conveying. A motor (1) of the present invention has a motor case (10), a shaft (2), a bracket (30), and a power supply terminal (42). The power supply terminal (42) extends in the radial direction from the bracket (30). A rotation stop portion (37) is provided on at least one of an output surface (top cover (12)) and an opposite surface (bottom cover (34)) of the motor (1), and gripping portions (14) and (36) are provided on both the output surface and the opposite surface of the output surface of the motor. The rotation stop portion and the gripped portion are located at positions approximately 90 DEG from the position of the power supply terminal (42) with the shaft (2) as the center.

Description

Motor, motor actuator provided with same, and packaging pallet for conveyance

Technical Field

The present invention relates to a small motor suitable for automatic assembly, and a motor actuator and a packaging pallet for transportation using the small motor.

Background

Fig. 12(a) shows a structure of a motor 70 according to a conventional example. The motor 70 includes a motor case 71 having an open end and accommodating a rotor and a stator (both not shown), and a resin bracket 72 is fitted to the open end of the motor case 71. A brush (not shown) for supplying electric power to the rotor and a power supply terminal 74 electrically connected to the brush are fixedly attached to the bracket 72. The power supply terminal 74 extends to the opposite side of the output surface of the bracket 72 and is connected to one end of the lead wire 75. The other end of the lead wire 75 is coated with a coating removed for connection to a power supply, and the core wire 76 is exposed.

Fig. 12(b) shows a structure of a motor actuator 80 using a motor of the conventional example. The motor actuator 80 is composed of a lower case 81, an upper case (not shown), a motor 70 serving as a power source, a plurality of gears 82 that decelerate and transmit power, an output shaft 83, and a connector pin 84 for supplying power from a power source. The power supply terminal 74 of the motor and the connector pin 84 are connected by a wire 75.

At this time, in order to avoid unnecessary contact with the fitting portion 81a of the housing and the connector pin 84, the lead wire 75 is wired so as to pass between the partitions 85 protruding upward from the lower housing 81. The connection with the connector pin 84 is mainly made by soldering. Connection to the wiring is performed manually, and therefore, it becomes an obstacle to automatic assembly. In addition, the space S for wiring the lead wire 75 needs to be on the opposite side of the output surface of the motor 70, which is difficult to miniaturize the actuator.

Therefore, a structure is proposed in which no wire is used for connecting the motor and the connector pin, and the assembly into the housing is facilitated.

The motor actuator described in patent document 1 has the following structure: an L-shaped portion is provided on a motor-side end of a power supply portion which is formed by insert molding of a single metal plate material into a resin, and a contact portion of the L-shaped portion is brought into press contact with a flat plate-shaped power supply terminal formed on a surface opposite to an output surface of a motor. According to this configuration, the length of the metal plate protruding from the power supply portion is adjusted in consideration of the difference in the height direction position of each power supply terminal of the motor without requiring a connection step such as drawing and welding of a lead wire, so that the elastic force of the contact portion with respect to the motor is equalized, and the assembly of the motor to the actuator case is facilitated.

Prior art documents

Patent document 1: japanese patent laid-open No. 2012 and 90510.

Disclosure of Invention

However, in patent document 1, since the contact portion on the power supply portion side and the power supply terminal on the motor side are connected only by contact, if the motor itself is unnecessarily rotated at the time of assembling the motor, the position of the power supply terminal may be shifted from a predetermined position, which may cause a contact failure. Further, a space for arranging the power supply portion and the contact portion is required on the opposite side of the output surface of the motor, and it is difficult to miniaturize the entire actuator.

Accordingly, the present invention provides a motor which can be easily and automatically assembled by eliminating rotation of a lead wire when the motor is assembled and preventing unnecessary rotation of the motor itself when the motor is assembled, a motor actuator using the motor, and a transporting packing tray for housing the motor.

The embodiments of the present invention that have been completed to solve the above problems are described below. The components in the respective embodiments described below can be combined as arbitrarily as possible. The embodiments and technical features of the present invention are not limited to the following descriptions, and can be recognized based on the technical features described in the entire specification and the drawings or the inventive idea that can be grasped by a person skilled in the art from these descriptions.

A motor according to an embodiment of the present invention includes:

a motor housing having a substantially cylindrical shape and an opening at one end, and accommodating a stator and a rotor having a shaft;

a bracket mounted at an opening end of the motor housing and accommodating an electric brush; and

a power supply terminal protruding from the bracket in a radial direction;

the motor is characterized in that:

comprising:

a rotation stopper formed on at least one of an output surface of the motor housing and a surface opposite to the output surface of the bracket; and

and a gripped part formed on a surface of the motor housing opposite to the output surface of the bracket.

The rotation stopper and the gripped portion are located at positions of approximately 90 ° in a circumferential direction around the axis from the position of the power supply terminal.

The invention has the following effects:

according to the present invention, the power supply terminal is extended to the side of the motor, so that a space on the opposite side of the output surface of the motor is not required. Further, since the rotation stopper and the gripped portion are provided at predetermined positions on the power supply terminal, the motor itself can be prevented from being unnecessarily rotated when the assembly is performed by the robot hand, and thus the automatic assembly of the motor can be easily performed.

Drawings

Fig. 1 is a perspective view of a finished motor according to a first embodiment of the present invention, in which (a) is a perspective view on an output surface side and (b) is a perspective view on an opposite side of the output surface.

Fig. 2 is a sectional perspective view of the motor of fig. 1.

Fig. 3 is an exploded perspective view of the motor, in which (a) is an exploded perspective view viewed from the side opposite to the output surface, and (b) is an exploded perspective view of the bracket viewed from the output surface side.

Fig. 4 is a schematic view showing a case where the motor of fig. 1 is held by a robot hand, wherein (a) is a cross-sectional view and (b) is a plan view seen from the opposite side of the output.

Fig. 5 is a plan view showing a modification of the gripped portion in the embodiment of fig. 1.

Fig. 6 is a partial cross-sectional view for explaining a case where the motor according to the first embodiment of the present invention is gripped by a hand.

Fig. 7 is a structural diagram of a motor actuator according to a second embodiment of the present invention, in which (a) is a plan view and (b) is a perspective view of a motor housing portion.

Fig. 8 is a sectional view a-a in fig. 7.

Fig. 9 is a schematic rear view showing a motor assembled by a robot.

Fig. 10 is a plan view showing a modification of the rotation stopper according to embodiment 2 of the present invention.

Fig. 11 is a perspective view of a motor-conveying packaging tray according to embodiment 3 of the present invention.

Fig. 12 is a structural diagram of a motor and a motor actuator according to the related art, in which (a) is a perspective view of the motor and (b) is a plan view of the motor actuator.

Description of the symbols

1 Motor

2 axle

3 magnet for driving

10 Motor casing

10a motor case

11 cylindrical part

11a open end

11b step part

12 Top cover

13 bearing

14 gripped part

20 rotor

21 armature core

22 winding

23 commutator

30 bracket

31 end plate

32 brush base

33 cylindrical part

34 bottom cover

35 brush base space part

36 part to be gripped

36a center axis of the gripped part

36CP center point of the gripped part

37 rotation stopping part

Center point of 37CP rotation stopping part

38 groove part

39 bearing

40 power supply part

41 electric brush

42 power supply terminal

43 fixed part

50 motor actuator

51 lower shell

51a bottom wall

51b side surface wall

Upper end of 51c side wall

51d first supporting part

52 housing part

52a partition

52b locking part

53 Gear

54 output shaft

55 connector pin

56 second support part

60 transport and use the bale tray

61 accommodating part

61a bottom

61b side wall

61c side wall

62 gap

63 stop part

70 motor

71 Motor casing

72 bracket

74 power supply terminal

75 conducting wire

76 core wire

80 motor actuator

81 lower casing

81a fitting part

82 gear

83 output shaft

84 connector pin

85 baffle

S wiring space

100 robot hand

Lower end of 100a robot

101 output surface side gripping part

102 opposite output surface side holding part

102a center axis of the grip part

103 gap.

Detailed Description

In the present specification, in fig. 1(a), a direction parallel to the shaft 2 of the motor 1 is referred to as an "axial direction", a direction in which the shaft 2 protrudes is referred to as an "output surface side", and an opposite direction thereof is referred to as an "opposite output surface side". The radial direction about the shaft 2 is simply referred to as the "radial direction", and the rotational direction of the shaft 2 is simply referred to as the "circumferential direction". In fig. 5 and 8, the upward direction is simply referred to as "upward", and the downward direction is simply referred to as "downward".

The vertical direction does not necessarily coincide with the positional relationship or direction when the device is assembled to an actual apparatus.

Hereinafter, embodiments of the present invention will be described exemplarily based on the drawings.

(embodiment 1)

A motor according to a first embodiment of the present invention will be described with reference to fig. 1 to 3. The motor 1 includes a shaft 2, a motor case 10, a driving magnet 3 as a stator, a rotor 20, a commutator 23, a bracket 30, and a power supply unit 40.

The motor case 10 is formed of an iron material having a rigid magnetic substance, and has a cover tubular shape having a cylindrical portion 11 and a top cover 12 integrally formed with one end of the cylindrical portion 11. A through hole is formed in the center of the top cover 12, and the bearing 13 is press-fitted into the through hole.

A grip 14 is provided above the output surface side of the top cover 12. In the present embodiment, the gripped portion 14 is constituted by a single hole. The gripped portion 14 is fitted to a gripping portion (a projection having substantially the same shape as the gripped portion 14) provided in a manipulator described later, thereby preventing the motor 1 from falling off or from unnecessarily rotating when gripping the motor.

The driving magnet 3 is fixed to the inner circumferential surface of the cylindrical portion 11. In the vicinity of the opening end portion 11a at the other end of the cylindrical portion 11, a step portion 11b having a diameter slightly larger than the diameter of the inner circumferential surface of the cylindrical portion 11 is formed over the entire circumference.

The rotor 20 has an armature core 21 formed by laminating a plurality of thin steel plates and a winding 22 wound around the armature core 21, and the shaft 2 is fixed at the center. A commutator 23 is fixed to the shaft 2 and electrically connected to the winding 22.

The shaft 2 is inserted through a bearing 13 and is rotatably supported. One end of the shaft 2 protrudes from the output face of the motor 1 (the top cover 12 of the motor housing). The other end of the shaft 2 is supported by a bearing 39 fixed to a brush base 32 described later.

The bracket 30 includes an end plate 31 formed of a rigid iron material and a brush base 32 formed of a non-conductive hard resin material. The end plate 31 is insert-molded to the brush base 32.

The brush base 32 has a bottomed cylindrical shape having a cylindrical portion 33 and a bottom cover 34 integrally formed with a lower end of the cylindrical portion 33, and has a brush base space portion 35 formed inside the bottomed cylindrical shape. A recess is formed in the center of the bottom cover 34, and a bearing 39 is press-fitted into the recess. The groove 38 is provided to accommodate and fix a power supply portion 40 including a brush 41 and a power supply terminal 42, which will be described later.

A grip 36 is provided on the bottom cover 34 on the opposite side of the output surface. In the present embodiment, the gripped portion 36 is formed of a single long hole. The gripped portion 36 is provided at the same position in the radial direction as the gripped portion 14 of the top cover 12 provided to the motor housing.

A rotation stopper 37 is provided on the bottom cover 34 below the side opposite to the output surface. In the present embodiment, the rotation stopper 37 is constituted by two concave portions. The rotation stopper 37 is fitted into a locking portion (a projection having substantially the same shape as the rotation stopper 37) provided in a motor actuator case and a motor transport packaging tray described later, thereby preventing the motor 1 itself from unnecessarily rotating. The rotation stopper 37 and the gripped portion 36 are located substantially on opposite sides in the radial direction.

The end plate 31 has a ring shape with the same outer diameter and inner diameter at the center, and a notch is provided in a portion from which a power supply terminal 42 described later is drawn. The outer diameter of the end plate 31 is the same as the size of the inner peripheral surface of the step portion 11 b. After the end plate 31 is inserted into the stepped portion 11b, the opening end portion 11a of the motor case is caulked to the end plate 31, and the bracket 30 is fixed to the opening end portion 11a of the motor case.

A pair of power feeding portions 40 are provided in the brush base 32 so as to be in sliding contact with the commutator 23 and to allow a current to flow therethrough. The power feeding portions 40 are arranged symmetrically about the shaft 2 inside the bracket 30.

The power feeding portion 40 is made of an elastic conductive material such as copper or a copper alloy, and is formed in a substantially flat plate shape elongated in the radial direction. The power supply portion 40 includes a brush 41 that is in sliding contact with the commutator 23 to supply current, a power supply terminal 42 for receiving supply of electric power from the outside, and a fixing portion 43 for fixing to the brush base 32, and is formed of the same member without interruption. The fixing portion 43 is inserted into the groove 38 formed in the brush base by press-fitting or the like, and the power supply portion 40 is fixed to the brush base 32.

The power supply terminal 42 protrudes radially outward from the bracket 30 and is disposed so as to exceed the outer peripheral surface 10a of the motor case, and is a male terminal that protrudes in a so-called lateral direction. At this time, the power supply terminal 42 and the gripped portions 14 and 36 (the center point 36CP in the case where a plurality of gripped portions are provided on the output surface or the surface opposite to the output surface as shown in fig. 5 (c)) are located at positions of substantially 90 ° in the circumferential direction around the shaft 2, and the power supply terminal 42 and the rotation stopper 37 (the center point 37CP in the case where a plurality of rotation stoppers are provided on the output surface or the surface opposite to the output surface as shown in fig. 5 and 10) are located at positions of substantially 90 ° in the circumferential direction around the shaft 2. The substantially 90 ° referred to herein is, for example, a range of 90 degrees ± 10 degrees, more preferably a range of 90 degrees ± 5 degrees, and particularly preferably a range of 90 degrees ± 2 degrees.

The features of the motor of the present invention when held by a robot will be described with reference to fig. 4.

When the motor 1 is gripped by the robot hand 100, the gripping portion 14 provided above the output surface side of the top cover 12 and the gripping portion 36 provided above the opposite side of the output surface of the bottom cover 34 are respectively fitted to the output surface side gripping portion 101 and the opposite side of the output surface gripping portion 102 of the robot hand 100, whereby the motor 1 can be gripped reliably.

In the present embodiment, the grip portion 102 on the opposite side of the output surface is a convex portion having substantially the same size as the grip portion 36. In this way, the gripped portion 36 can be geometrically constrained without depending on the friction force and cannot move in any direction, and therefore, unnecessary rotation of the motor 1 at the time of assembly can be prevented.

Further, since the motor 1 is geometrically gripped, it is possible to reliably grip the object with a lower gripping force than a gripping mechanism that relies only on a frictional force. Therefore, it also contributes to downsizing and power saving of the device of the robot hand 100.

In the present embodiment, the gripped portion 36 is an elongated hole, but may have a shape different in the longitudinal direction as shown in fig. 5 (a). As shown in fig. 5(b), the gripped portion 36 may be a square hole. In this case, the grip portion 102 on the hand side is a square projection having substantially the same size. On the contrary, the gripped portion 36 may be a projection instead of a hole. In this case, the grip portion 102 on the hand side is a concave portion having substantially the same shape. As shown in fig. 5(c), the gripped portion 36 may have a plurality of holes. In this case, the gripping portion 102 on the hand side is formed as a plurality of protrusions having substantially the same shape and the same arrangement. Conversely, the gripped portion 36 may be a plurality of protrusions. In this case, the gripping portions 102 on the hand side are formed as a plurality of corresponding concave portions. In the case where the gripped

parts

14 and 36 are holes, the holes may be through holes or non-through holes. These modifications of the gripped portion 36 can be similarly applied to the gripped portion 14 on the output surface side.

As shown in fig. 6(a), the gripped

portions

14 and 36 may have a substantially tapered cross section. By forming the grip portion 102 of the manipulator to have a tapered convex shape having substantially the same shape, the central axis 36a of the gripped portion 36 can be aligned with the central axis 102a of the grip portion 102. Further, as shown in fig. 6(b), the unnecessary gap 103 is not present in the fitting portion between the gripped portion 36 and the gripping portion 102, and therefore, the accuracy of positioning and angle determination during gripping is further improved.

(embodiment 2)

An example of a motor actuator according to a second embodiment of the present invention will be described with reference to fig. 7 to 9. The motor actuator 50 includes a lower case 51, an upper case (not shown), a motor 1 serving as a power source, a plurality of gears 53 that decelerate and transmit power, an output shaft 54, and a connector pin 55 for supplying power from a power source.

The lower case 51 has a bottom wall 51a and four side walls 51b, and has a substantially rectangular container shape with one open side. Similarly, an upper case (not shown) having an opening on one surface and the opening surface are aligned and assembled to form a cover body having a predetermined internal space.

The lower case 51 is provided with a housing 52 for the motor 1. One of the receiving portions 52 is a side wall 51b of the lower case 51, and the other is provided with a partition plate 52a to prevent the axial movement of the motor 1 received in the receiving portion 52. The side wall 51b accommodates the side opposite to the output surface of the motor 1, and the partition plate 52a accommodates the side of the output surface of the motor 1.

The side wall 51b of the housing 52 is provided with a locking portion 52 b. The locking portion 52b is formed such that a projection having substantially the same shape as the rotation stopper 37 protrudes from the bottom wall 51a so as to extend along the side wall 51b, in order to reliably lock the rotation stopper 37 of the motor 1.

The motor 1 is the same as the motor of embodiment 1.

The motor 1 is assembled to the housing portion 52 from above by the robot hand 100. At this time, since the gripped

portions

14 and 36 of the motor 1 are geometrically constrained by being fitted to the output surface side gripping portion 101 and the output surface opposite side gripping portion 102 of the robot hand 100, respectively, the motor 1 itself does not unnecessarily rotate during assembly, and can be reliably assembled to the housing portion 52.

Fig. 9 is a diagram showing a state in which the motor 1 is assembled to the lower case 51 using the robot hand 100. In fig. 9, (a) shows the case of the present embodiment, (b) shows the case where the gripped portion 36 is located near the center of the bottom cover 34, and (c) shows the case where the cylindrical portion 11 of the motor housing 10 is gripped. In the example shown in fig. 9(b) and 9(c), the lower end 100a of the robot arm is in contact with the upper end 51c of the side wall 51b, and therefore the motor 1 cannot be assembled in the vicinity of the side wall 51 b.

On the other hand, in the present embodiment shown in fig. 9(a), since the gripped

parts

14 and 36 are provided in the upper direction on the output side of the motor 1 and the opposite side of the output side, when the robot 100 is used and assembled in the vicinity of the side wall 51b of the housing, the lower end 100a of the robot 100 does not come into contact with the upper end 51c of the side wall 51b of the lower housing. Therefore, the motor 1 can be provided in the vicinity of the side wall 51b of the lower case, contributing to downsizing of the entire motor actuator.

In the motor 1, since the rotation stopper 37 is assembled to the locking portion 52b, unnecessary rotation of the motor 1 itself does not occur even after the assembly. Therefore, the power supply terminal 42 extending laterally from the bracket 30 is always disposed at a predetermined position without causing positional deviation or angular deviation.

The connector pin 55 is provided so as to be close to the power supply terminal 42 at the time of assembling the motor 1, and is electrically connected by an arbitrary method. In the present embodiment, the first support portion 51d projecting upward from the bottom wall 51a and the second support portion 56 projecting downward from the upper case (not shown) are pressed into contact with each other.

The driving force of the motor 1 is transmitted to an output shaft 54 via a plurality of gears 53 including worm gears. A crank or the like, not shown, is attached to the output shaft 54.

By configuring the motor 1 and the motor actuator 50 as described above, a wire winding process is not required, and automatic mounting using a robot is facilitated. In addition, the space S on the opposite side of the output surface of the motor 1 is hardly required, which contributes to downsizing of the entire motor actuator 50.

In the present embodiment, the rotation stopper 37 is two concave portions, but may be one convex portion as shown in fig. 10 (a). As shown in fig. 10(b), the rotation stopper 37 may be provided in plural numbers of three or more. In this case, the plurality of rotation stoppers 37 may be a combination of concave portions and convex portions. As shown in fig. 10(c), the rotation stopper 37 may be a recess formed upward from below the surface opposite to the output surface. As shown in fig. 10(d), the rotation stopper may be the rotation stopper 37 or may be a plurality of guide grooves. The shape of the rotation stopper 37 is not limited.

In the present embodiment, the rotation stopper 37 is provided on the opposite side of the output surface, but may be provided only on the output surface side, or may be provided on both the output surface and the opposite output surface.

(embodiment 3)

An example of a motor packing tray according to a third embodiment of the present invention will be described with reference to fig. 11. The transport packaging tray 60 is obtained by molding a resin such as polyethylene terephthalate (PET) or Polyethylene (PE) to a thickness of 1mm or less by vacuum molding or the like. The conveying bundling tray 60 is provided with a predetermined number of accommodating portions 61 for accommodating the motors 1 in parallel. The conveying packaging tray 60 contains a predetermined number of motors 1, and then is stored in an outer box such as a corrugated cardboard box in a state of being stacked in multiple layers.

The receiving portion 61 has a substantially cylindrical bottom portion 61a for holding the cylindrical portion 11 of the motor housing 10, and side walls 61b and 61c located at both ends of the bottom portion 61 a. The side walls 61b and 61c hold the top cover 12 and the bottom cover 34 of the motor 1, respectively, against movement in the axial direction.

The bottom portion 61a is provided with a notch 62 so that the power supply terminal 42 does not contact the bottom portion 61a when the motor is housed.

The locking portion 63 is provided on the side wall 61c of the motor 1 on the bottom cover 34 side. Since the engagement portion 63 is reliably engaged with the rotation stopper 37 of the motor 1, a convex portion having substantially the same shape protrudes from the bottom portion 61a so as to extend along the side wall 61 c.

Since the rotation stopper 37 is fitted to the locking portion 63, the motor 1 itself does not rotate unnecessarily in the packaging tray even if vibration is applied during conveyance. Since the motor 1 and the gripped

portions

14 and 36 are held at predetermined positions, the robot hand can reliably grip the object at the time of taking out the object.

While the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications other than the above-described embodiments can be made without departing from the spirit of the present invention.

Claims

1. A motor, comprising:

a holder having a substantially cylindrical shape, attached to an opening end of the motor case, and accommodating a brush; and

a power supply terminal protruding from the bracket in a radial direction;

the method is characterized in that:

comprising:

2. The motor of claim 1,

3. The motor of claim 2,

the gripped portion and the rotation stopper portion are located at positions substantially opposite to each other with the shaft as a center.

4. The motor of claim 1,

at least one of the gripped portions is a non-circular hole or a non-circular projection.

5. The motor of claim 1,

at least one of the gripped portions is a plurality of holes or a projection.

6. The motor of claim 1,

the gripped part has a tapered shape.

7. The motor of claim 1,

the brush is formed of a plate material having elasticity,

one end side of the plate is the power supply terminal.

8. A motor actuator includes:

the motor of any one of claims 1 to 7;

a gear that decelerates and transmits a rotational driving force of the motor;

an output shaft that outputs a rotational driving force to the outside;

a connector pin to supply power to the motor; and

a housing for accommodating the above components,

the motor actuator is characterized in that it is,

and a locking part which is locked with the rotation stopping part is arranged on the bottom surface of the shell.

9. The motor actuator of claim 8,

the motor is assembled in the case such that the power supply terminal is substantially parallel to a bottom surface of the case.

10. The motor actuator of claim 9,

the housing is composed of a lower housing and an upper housing, and a support portion for supporting an electrical connection point between the power supply terminal and the connector pin is provided inside at least one of the lower housing and the upper housing.

11. The motor actuator of claim 10,

the gripped portion is provided at a position exposed from an opening surface of the housing when the motor is assembled to the housing.

12. A packaging pallet for motor transportation, comprising a housing portion for housing the motor according to any one of claims 1 to 7,

the packing pallet for motor transportation is characterized in that,

the housing portion has a locking portion that locks with the rotation stopper portion.

13. The motor-driven bale pallet of claim 12, wherein the bale pallet is a round-bottomed round,

an accommodating portion is formed so that the gripped portion is exposed from the accommodating portion when the motor is accommodated in the accommodating portion.

14. The motor-driven bale pallet of claim 12, wherein the bale pallet is a round-bottomed round,

the accommodating portion is provided with a notch for avoiding contact with the power supply terminal.