Traction gear device and robot

Abstract

Traction transmission device (1) which transmits a driving force of a motor (2) which drives a drive shaft (3) to an output shaft (6) using a circumferential intermediate member (10) which is stretched between a drive wheel (4) which is attached to the drive shaft (3) and an output wheel (5) which is attached to the output shaft (6), wherein the traction transmission device (1) comprises: a housing (20) with which a sealing structure is formed that seals a space in which the enclosing intermediate member (10) is arranged; a first bracket (40) to hold the motor (2); and a second bracket (8) to rotatably hold the output shaft (6), wherein a support, which is the first support (40) and / or the second support (8), is attached to the housing (20) to form part of the sealing structure, and wherein a sealant (45, 42) is provided which closes a gap between the holder (40) and the housing (20), characterized in that an elongated hole (22) is formed in the holder (40), and the holder (40) is attached to the housing (20) by an adjusting screw (43) which is screwed through the elongated hole (22) and tightened in the housing (20).

Description

Area

[0001] The present invention relates to a traction gear device that transmits a driving force of a motor to an output shaft using a circumferential intermediate element that is stretched between a drive wheel and an output wheel, and to a robot. background

[0002] In a traction drive device that transmits the driving force of a motor to an output shaft, a flexible, encircling link, such as a belt or chain, is stretched between a drive wheel, which rotates according to the driving force of the motor, and a driven wheel, which rotates around the output shaft. The encircling link receives the driving force from the driven wheel and rotates between the drive and driven wheels, thus rotating the driven wheel. If the tension of the encircling link decreases, it becomes difficult to transmit driving force from the drive wheel to the driven wheel. To maintain the tension that enables the transmission of driving force from the drive wheel to the driven wheel, it is necessary to adjust the tension of the encircling link.

[0003] Patent literature 1 discloses that an actuator device comprising a clasping intermediate element for transmitting a driving force from a motor to an actuator is provided with a tension adjustment unit that adjusts the tension of the clasping intermediate element. A fastening screwed through an elongated hole formed in an actuator mount is tightened in a motor mount, thereby securing the motor to the actuator. By loosening the fastening, the motor and the actuator can be moved relative to each other in the longitudinal direction of the elongated hole. The tension adjustment unit adjusts the tension of the clasping intermediate element by the relative movement between the motor and the actuator.

[0004] German publication DE 103 04 189 A1 discloses an electric power steering device with a motor, which includes a speed-reducing mechanism comprising a belt for connecting an input pulley and an output pulley and a means for adjusting the belt tension. Furthermore, publication D1 discloses a housing for the speed-reducing mechanism, which has a circumferential wall that is fluid-tight against the circumferential wall and an end wall.

[0005] German patent application DE 10 2007 008 246 A1 discloses a device for tensioning the belt of an electric power steering drive. The document further discloses an elongated hole formed in a bracket, through which the center distance between the steering shaft and the motor shaft can be adjusted. Citation list of patent literature

[0006] Patent literature 1: Published Japanese patent application no. 2017-8971 Overview Technical Problem

[0007] A traction transmission device may be installed in a location exposed to harmful substances that could cause a change or breakage of the encircling link or a decrease in transmission force. Examples of harmful substances include water, oil, chemicals, and dust. To protect the encircling link from these harmful substances, it is necessary to isolate it from the environment in which the harmful substances exist by placing it in a sealed enclosure.

[0008] However, in the actuator device described in patent literature 1, the elongated hole is provided in the actuator holder, which forms an exterior part of the actuator device, and therefore there is a problem in that the encircling intermediate element cannot be arranged in a sealed space.

[0009] The present invention was made in view of the above circumstances, and its objective is to provide a traction gear device that is able to more easily adjust the tension of an encircling intermediate member in a sealed space. Solution to the problem

[0010] To solve the aforementioned problem, a traction device with the features of the independent claim of the present invention is provided. Advantageous embodiments of the invention are defined in the dependent claims, the description, and the drawings of the present invention.

[0011] Accordingly, a traction transmission device that transmits a driving force from a motor driving a drive shaft to an output shaft, using an encircling intermediate member stretched between a drive wheel attached to the drive shaft and an output wheel attached to the output shaft, the traction transmission device comprising: a housing forming a sealing structure that seals a space in which the encircling intermediate member is arranged; a first support for holding the motor;and a second bracket for rotatably holding the output shaft, wherein a bracket, which is the first bracket and / or the second bracket, is attached to the housing to form part of the sealing structure, and wherein a sealing means is provided which closes a gap between the bracket and the housing, characterized in that an elongated hole is formed in the bracket, and the bracket is fastened to the housing by an adjusting screw which is screwed through the elongated hole and tightened in the housing. Advantageous effect of the invention

[0012] The traction gear device according to the present invention achieves the advantageous effect that an encircling intermediate member can be arranged in a sealed space. Brief description of the drawings Fig. Figure 1 is a cross-sectional view showing a main part of a traction gear device according to a first embodiment of the present invention. Fig. 2 is a top view showing part of the Fig. Figure 1 of the traction gear device shows where a bracket is provided. Fig. 3 is a view showing a cross-section along a line III-III in Fig. 2 shows. Fig. 4 is an enlarged view of one in Fig. Part A shown in section 1. Fig. 5 is an enlarged view of one in Fig. Part B shown in section 3. Fig. Figure 6 is a view showing a robot according to a second embodiment of the present invention. Fig. 7 is a view showing a cross-section along a line VII-VII in Fig. 6 shows. Description of embodiments

[0013] A traction drive device and a robot according to embodiments of the present invention are described below with reference to the drawings. The present invention is not necessarily limited to these embodiments. First embodiment.

[0014] Fig. Figure 1 is a cross-sectional view showing a main part of a traction device 1 according to a first embodiment of the present invention. The traction device 1 transmits a driving force from a motor 2 to an output shaft 6 using a circumferential intermediate element 10. The motor 2 rotates a drive shaft 3. A drive wheel 4 is attached to the drive shaft 3. The drive wheel 4 rotates depending on the driving force of the motor 2. An output wheel 5 is attached to the output shaft 6.

[0015] The encircling intermediate link 10 is stretched between the drive wheel 4 and the driven wheel 5. The encircling intermediate link 10 is a friction belt made of rubber or the like, such as a flat belt or a V-belt. The encircling intermediate link 10 can be a toothed belt made of rubber or the like, a chain made of iron or the like.

[0016] The traction gear device 1 comprises a housing 20 that defines a space 60 in which the encircling intermediate member 10 is arranged. A bracket 40, which is a first bracket, and a bracket 8, which is a second bracket, are attached to the housing 20. The bracket 40 holds the motor 2. The bracket 40 closes an opening formed in the housing 20 from outside the space 60. The motor 2 is held in a position in which the drive wheel 4 enters the space 60 from outside the space 60 through the opening.

[0017] A bearing 7 is provided on the bracket 8. The bracket 8 rotatably holds the output shaft 6 via the bearing 7. The bracket 8 closes an opening formed in the housing 20 from outside the space 60. The output shaft 6 is held in a position in which the output gear 5 enters the space 60 from outside the space 60 through the opening.

[0018] A cover 11 is attached to the housing 20, thereby closing off a portion of the housing 20, forming the space 60. The space 60 is enclosed by the housing 20, the bracket 40, the support 8, and the cover 11. The housing 20, the bracket 40, the support 8, and the cover 11 form a sealing structure that seals the space 60. With such a sealing structure, the space 60 is isolated from its environment. The support 40 and the support 80 are attached to the housing 20, thus forming part of the sealing structure.

[0019] A sealant 12, which closes a gap between the housing 20 and the cover 11, is provided on a region of the housing 20 that is in contact with the cover 11. A sealant 41, which closes a gap between the bracket 40 and the motor 2, is provided on a region of the bracket 40 that is in contact with the motor 2. A sealant 42, which closes a gap between the bracket 40 and the housing 20, is provided on a region of the bracket 40 that is in contact with the housing 20. The sealant 42 is provided along an outer edge of the bracket 40 and surrounds the motor 2 in an annular manner. A sealant 9, which closes a gap between the bracket 8 and the housing 20, is provided on a portion of the bracket 8 that is in contact with the housing 20. The sealant 9 is provided along an outer edge of the bracket 8 and surrounds the output shaft 6 in an annular manner.With the sealing means 9, 12, 41 and 42 provided on the traction gear device 1, the enclosing intermediate member 10 can be arranged in a space 60 which is hermetically closed and is able to prevent the ingress of air into the space 60 from outside the space 60.

[0020] A projecting area 21 is formed outside the space 60 in the housing 20. A tension adjustment screw 30 extends through the projecting area 21. A tension adjustment fitting 31 is attached to the bracket 40. A fastening screw 33 is screwed through the tension adjustment fitting 31 and tightened in the bracket 40 to secure the tension adjustment fitting 31 to the bracket 40.

[0021] A portion of the tension adjustment screw 30, near its tip, is screwed through the tension adjustment fitting 31. A nut 32 is attached to the tension adjustment screw 30 at the screw tip end of the tension adjustment fitting 31. The tension adjustment screw 30, the tension adjustment fitting 31, the nut 32, and the fastening screw 33 form a tension adjustment mechanism. The tension adjustment mechanism adjusts the tension of the encircling intermediate member 10. In the first embodiment, the tension adjustment mechanism adjusts the tension of the encircling intermediate member 10 by moving the bracket 40 integrated with the motor 2. The tension adjustment mechanism is located outside the space 60.

[0022] The traction device 1, used at a production site or the like, can be installed in a location exposed to harmful substances. A harmful substance is one that causes a change or breakage of the encircling intermediate member 10 or a decrease in the transmission force, and which may be in the form of substances such as water, oil, chemicals, and dust. In the traction device 1, the encircling intermediate member 10 is arranged in the space 60, which is hermetically sealed by the sealing structure, thus isolating the encircling intermediate member 10 from an environment containing such a harmful substance. As a result, the traction device 1 can reduce the change and breakage of the encircling intermediate member 10 and the decrease in the transmission force across the encircling intermediate member 10.

[0023] While the encircling intermediate element in the traction device 1 is located within the sealed space 60, a configuration that does not require isolation from the harmful substance is located outside of space 60. The traction device 1 can protect the encircling intermediate element 10 with a small and simple sealing structure, compared to a case where the entire traction device 1 is sealed.

[0024] Fig. 2 is a top view showing part of the Fig. Figure 1 of the traction gear device shows where the bracket 40 is provided. Fig. 3 is a view showing a cross-section along a line III-III in Fig. 2 shows. Fig. Figure 2 shows an area where the motor 2 and the bracket 40 are located when viewed from below. Fig. 1 are planned.

[0025] A fastening screw 50 secures the motor 2 to the bracket 4. Two elongated holes 22 are formed in the bracket 40. The longitudinal direction of the elongated hole 22 is perpendicular to the drive shaft 3, which corresponds to a direction parallel to a straight line passing through the drive shaft 3 and the output shaft 6. An adjusting screw 43, serving as a fastening tool, is screwed through each of the two elongated holes 22. The bracket 40 is fastened to the housing 20 by the adjusting screw 43, which is screwed through the elongated hole 22 and tightened in the housing 20. Fig. 2 each of the elongated holes 22 is provided in an area that is covered by a screw head of the adjusting screw 43. Fig. Figure 3 shows a cross-section of an area of ​​the Fig. 2 configuration shown, where an elongated hole 22 is provided, the cross-section being parallel to the longitudinal direction.

[0026] A sealant 45 is designed to surround the elongated holes 22 and fill a gap between the bracket 40 and the housing 20. The sealant 45 is provided in each of the two elongated holes 22. Fig. The sealing elements 42 and 45, which are concealed by the holder 40, are shown by dashed lines. The sealing element 45, as provided, prevents air from entering the space 60 through the elongated holes 20 from outside the space 60.

[0027] The tension adjustment is now described by the tension adjustment mechanism. The adjusting screw 43 is loosened until the mounting of the bracket 40 to the housing 20 is released, allowing the bracket 40 to move longitudinally. If the tension is insufficient, the tension adjustment mechanism pulls the tension adjustment element 31 toward the protruding section 21 by turning the tension adjustment screw 30 after the adjusting screw 43 has been loosened. As the tension adjustment element 31 is pulled toward the protruding section 21, the bracket moves to the right. Fig. 2, together with the tension adjusting fitting 31. The movement of the bracket 40 causes the drive shaft 3 to move away from the output shaft 6. The distance between the drive shaft 3 and the output shaft 6 increases, thereby increasing the tension of the encircling intermediate member 10. Once the distance between the drive gear 4 and the output gear 5 has increased sufficiently for the tension to transmit a driving force from the drive gear 4 to the output gear 5, the bracket 40 is secured to the housing 20 by tightening the adjusting screw 43. After the tension adjusting fitting 31 has been pulled towards the projecting area 21, the bracket 40 is secured to the housing 20 by tightening the adjusting screw 43. In this way, the tension adjusting mechanism performs an adjustment to increase the tension of the encircling intermediate member 10.

[0028] Conversely, if the tension is too high, the tension adjustment mechanism moves the tension adjustment fitting 31 away from the projecting area 21 by turning the tension adjustment screw 30 in a direction opposite to the direction in which the tension is increased. As the tension adjustment fitting 31 moves away from the projecting area 21, the bracket 40 moves within the Fig. 2 to the left, together with the tension-adjusting fitting 31. The movement of the bracket 40 causes the drive shaft 3 to move in one direction, so that it approaches the output shaft 6. By moving the drive shaft 3 closer to the output shaft 6, the tension of the encircling intermediate member 10 is reduced. After the encircling intermediate member 10 has been loosened sufficiently to achieve a suitable tension, the bracket 40 is secured to the housing 20 by tightening the adjusting screw 43. In this way, the tension-adjusting mechanism performs an adjustment to reduce the tension of the encircling intermediate member 10.

[0029] In the traction device 1, the tension of the encircling intermediate member 10, which is arranged in the space 60, can be adjusted by the tension adjusting screw 30, which is turned outside the space 60. As a result, the traction device 1 can adjust the tension of the encircling intermediate member 10 without opening the sealing structure.

[0030] Fig. 4 is an enlarged view of one in Fig. In the area shown in Figure 1, the sealant 42 is inserted into a recess 46 formed in the holder 40. The recess 46 is filled with a lubricant 44, such as grease. The recess 46 can be provided in the housing 20 instead of the holder 40, or it can be provided in both the holder 40 and the housing 20. The recess 46 need only be formed in the holder 40 and / or the housing 20.

[0031] In a state where the bracket 40 is attached to the housing 20, the sealant 42 is pressed into the recess 46. When the bracket 40 is released from the housing 20 by loosening the adjusting screw 43 at the time of tension adjustment, the sealant 42 expands due to an elastic force. As a result, the tensioning device 1 can maintain a state in which the gap between the bracket 40 and the housing 20 is closed by the sealant 42 during tension adjustment.

[0032] Since the lubricant 44 is enclosed in the recess 46, the sealant 42 can easily slide along the surface of the housing 20 while maintaining contact between the housing 20 and the sealant 42. As a result, the traction device 1 can easily move the bracket 40 while maintaining the condition in which the gap between the bracket 40 and the housing 20 is closed by the sealant 42.

[0033] Fig. 5 is an enlarged view of one in Fig. 3 shown area B. The sealant 45 is similar to the one in Fig. 4. Sealing material 42 shown is provided. The sealing material 45 is inserted into a recess 47 formed in the holder 40. The recess 47 is filled with the lubricant 44, such as grease. The recess 47 can be provided in the housing 20 instead of the holder 40, or it can be provided in both the holder 40 and the housing 20. The recess 47 need only be formed in the holder 40 and / or in the housing 20.

[0034] The traction device 1 can maintain a state in which the gap between the bracket 40 and the housing 20 is closed by the sealing agent 45 at the time of tension adjustment. Since the lubricant 44 is further enclosed in the recess 47, the traction device 1 can easily move the bracket 40 while maintaining the state in which the gap between the bracket 40 and the housing 20 is closed by the sealing agent 45.

[0035] For the sealants 42 and 45, a material is used that exhibits elasticity, resistance to environmental influences, and resistance to chemicals, and that can be reused. A material such as nitrile rubber, fluorocarbon rubber, or silicone rubber can be used for the sealants 42 and 45. Since the sealants 42 and 45 are provided, the tensioning device 1 can adjust the tension of the encircling intermediate member 10 while maintaining the hermetic seal of the space 60. A material similar to that of the sealants 42 and 45 can also be used for the sealants 9, 12, and 41 mentioned above.

[0036] In the first embodiment, the tension adjustment mechanism changes the relative position between the drive shaft 3 and the output shaft 6 by moving the position of the drive shaft 3 while keeping the position of the output shaft 6 constant, thereby adjusting the tension of the encircling intermediate member 10. The tension adjustment mechanism only needs to change the relative position between the drive shaft 3 and the output shaft 6, and it can move the position of the output shaft 6 while keeping the position of the drive shaft 3 constant. The tension adjustment mechanism can also move both the drive shaft 3 and the output shaft 6. Therefore, the tension adjustment mechanism only needs to relocate the bracket 40 and / or the bracket 8.

[0037] The traction device 1 is not limited to the type in which both the bracket 40 and the bracket 8 form part of the sealing structure. The traction device 1 need only be of a type in which the bracket 40 and / or the bracket 80 form part of the sealing structure. The traction device 1 need only have a configuration in which the bracket 40 and / or the bracket 8 is movable for the purpose of tension adjustment and forms part of the sealing structure. As a result, in the traction device 1, the encircling intermediate member 10 can be arranged in the sealed space 60, and the sealed space 60 can be maintained during tension adjustment.

[0038] According to the first embodiment, the traction device 1 comprises the housing 20, which forms a sealing structure, the support 40, and the bracket 8, wherein the support 40 and / or the bracket 8 is attached to the housing 20 to form part of the sealing structure. As a result, the traction device 1 achieves the effect that the encircling intermediate member 10 is arranged in the sealed space 60. Second embodiment.

[0039] Fig. Figure 6 is a view showing a robot 70 according to a second embodiment of the present invention. The robot 70 comprises a traction device 1 according to the first embodiment. In the second embodiment, the components that are identical to those of the first embodiment are designated by the same reference numerals, and essentially different configurations are described.

[0040] The robot 70 is a machine that performs work on a workpiece, such as a product. The robot 70 comprises a base 71, a shaft section 72 which is rotatably mounted relative to the base 71, a shaft section 73 which is connected to the shaft section 72, a shaft section 74 which is connected to the shaft section 73, and a distal end section 75 which is connected to the shaft section 74. The distal end section 75 is equipped with a hand for gripping the workpiece. Fig. Figure 6 omits the hand illustration. The shaft sections 72, 73, and 74 and the end section 75 form an arm unit contained within the robot 70. The robot 70 changes its position by rotating the connecting sections between each pair of adjacent shaft sections 72, 73, and 74, and by rotating the connecting section between the shaft section 72 and the base 71. The robot 70 can move the distal end section 75 into different positions by changing its orientation.

[0041] Fig. 7 is a view showing a cross-section along a line VII-VII in Fig.Figure 6 shows the traction device 1, which is arranged in a housing 76 of the robot 70. The motor 2 is attached to the shaft section 34. The output shaft 6 is located at a connection point between the shaft section 74 and the distal end section 75. In the robot 70, the traction device 1 transmits the drive force of the motor 2, which is located at a position different from that of the connection point, to the output shaft 6, which is located at the connection point.

[0042] According to the second embodiment, the robot 70 includes the traction device 1 according to the first embodiment, such that the encircling intermediate member 10 can be arranged in the sealed space 60. In a case where the robot 70 is installed in a location exposed to harmful substances, the encircling intermediate member 10 can be isolated from the environment in which the harmful substance exists. As a result, the robot can reduce the risk of damage to and breakage of the encircling intermediate member 10 and minimize a reduction in the transmission force due to the encircling intermediate member 10. Since the encircling intermediate member 10 can be sealed by a smaller and simpler sealing structure in the robot 70, it is possible to achieve both miniaturization of the robot 70 and protection of the encircling intermediate member 10.

[0043] The traction device 1 can be used for a device other than the robot 70. The traction device 1 can be used for a device installed at a manufacturing site, such as a conveyor that moves a workpiece, factory equipment, or a machine tool. Even in a situation where the traction device 1 is used for a device installed at a location exposed to harmful substances, the encircling intermediate element 10 can be protected from the harmful substance.

[0044] The configurations described in the above embodiments are merely examples of the content of the present invention, and they can be combined with other known techniques and partially omitted and / or modified without departing from the scope of the present invention. Reference symbol list 1 Traction gear device; 2 Motors; 3 Drive shaft; 4 drive wheel; 5 Output gear; 6 Output shaft; 7 warehouses; 8, 40 bracket; 9, 12, 41, 42, 45 sealant; 10 encircling intermediate element; 11 Cover; 20, 76 cases; 21 above area; 22 elongated holes; 30 tension adjustment screw; 31 Tension adjusting fitting; 32 Mother; 33, 50 fastening screw; 43 Adjusting screw; 40 lubricants; 46, 47 Exclusion; 60 rooms; 70 robots; 71 base; 72, 73, 74 shaft area; 75 distal end

Claims

[1] Traction transmission device (1) which transmits a driving force from a motor (2) driving a drive shaft (3) to an output shaft (6) using a wrap-around intermediate member (10) which is stretched between a drive wheel (4) attached to the drive shaft (3) and an output wheel (5) attached to the output shaft (6), wherein the traction transmission device (1) comprises: a housing (20) with which a sealing structure is formed that seals a space in which the enclosing intermediate member (10) is arranged; a first bracket (40) to hold the motor (2); and a second bracket (8) to rotatably hold the output shaft (6), wherein a support, which is the first support (40) and / or the second support (8), is attached to the housing (20) to form part of the sealing structure, and wherein a sealant (45, 42) is provided which closes a gap between the holder (40) and the housing (20), characterized by , that a slot (22) is formed in the holder (40), and the holder (40) is attached to the housing (20) by an adjusting screw (43) which is screwed through the slot (22) and tightened in the housing (20). [2] Traction device (1) according to claim 1, wherein the sealing means (45) surrounds the elongated hole (22). [3] Traction device (1) according to claim 1, wherein the sealing medium (42) surrounds the motor (2). [4] Traction gear device (1) according to claim 2 or 3, wherein the sealing agent (45, 42) is arranged in a recess (46, 47) formed in the holder (40) and / or the housing (20), and wherein a lubricant (44) is enclosed in the recess (46, 47). [5] Traction device (1) according to any one of claims 1 to 4, further comprising a tension adjustment mechanism configured to adjust the tension of the encircling intermediate member (10) by moving the holder (40) to a state in which the adjusting screw (43) is loosened. [6] Traction device (1) according to claim 5, wherein the tension adjustment mechanism is provided outside the space (60). [7] Robot (70) with the traction gear device (1) according to any one of claims 1 to 6.

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