JP2007120692A - Resilient force generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device capable of accumulating a strong force by a small motor and generating a strong resilient force. <P>SOLUTION: The resilient force generating device 1 is constituted by winding a twist spring 5 around a shaft for pivoting an actuating member 3 with a supporting point and fixed to a housing and by forming a cam follower contacting with a cam outer circumference surface at a cam follower rod end by rolling friction. One end of the twist spring 5 is fixed to a housing and the other end is fixed at an actuator rod 13-1 of an actuating member and the twist spring 5 functions to generate a resilient force by accumulating a force by the rotation of the actuating member and releasing the constraint of the cam follower. In this case, an outer circumference surface profile wherein a normal of the cam circumference surface at a point of the application of a force and a line connecting a supporting point of the actuating member and the rotation axial center of the cam follower is vertical or approximately vertical is provided and a cam and a rotation driving device of the cam for releasing the constraint of the actuating member by its step are provided in the resilient force generating device. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  INDUSTRIAL APPLICABILITY The present invention is suitable for use in places that require a large resilience, such as an amusement device, rescue robot, press machine, hammering device, etc. Relates to the device.

  There are a wide range of fields that require strong resilience, such as kickers in robots, legs with jump functions, and press machines and hammering devices in the metal processing field.

  As a means for generating an elastic force, as shown in FIG. 10, the upper part of the fulcrum J of the actuator A as shown in FIG. O Applying an elastic force to the left side of the ball as viewed in the figure, for example, or as shown in FIG. 10B, the lower part of the fulcrum J of the actuator A is displaced in the direction of the arrow to Further, as shown in FIG. 10 (c), application of force is applied to the object O, for example, a ball, directly by the solenoid S. Further, as shown in FIG. 11, the elastic force generated when the elastic body E is expanded and contracted is applied to the object O.

On the other hand, as shown in FIG. 12, there is known an apparatus that applies an elastic force to the back surface of the belt in order to peel off the transported material remaining on the surface of the conveyor belt (see, for example, Patent Document 1). In this prior art, as shown in FIG. 12A (FIG. 4 in the cited patent document), a roller 116 (cam follower) that is in rolling contact with the inner peripheral surface of the cam 111 fixed to the cam shaft 110 By rotating clockwise, the rod 115 is raised, and in this process, the elastic spring 118 placed on the spring receiver 117 is compressed in the case 119, and the roller 116 (cam follower) suddenly moves at the stepped portion of the cam 111. By displacing in the vertical direction, the compressive force of the elastic spring 118 is released, and an elastic force is applied to the hammer head 120 formed integrally with the rod 115. As a result, as shown in FIG. 12B (FIG. 5 in Patent Document 1), the hammer head 120 is caused to collide with the back surface of the conveyor belt 101 in the return process from the head pulley 102 in the hopper 109, and the conveyor belt 101. The transported material remaining on and attached to the surface is peeled off. In FIG. 12, reference numeral 119a denotes a stopper, which stops the spring receiver 117 at this position. In FIG. 12B, 108 is a motor that functions to rotate the cam 111, 104 is a driving sprocket wheel, 105 is a driven sprocket wheel, 106 is a chain, and 107 is an idler.
JP 2001-151332 A

On the other hand, in a camera, a mechanism for accumulating a force in a torsion spring and releasing a force accumulated in the torsion spring by a cam and operating a shutter to perform a shutter operation is also known (for example, in Patent Document 2). (See FIGS. 1 and 2).
Japanese Patent Application Laid-Open No. 07-219010

  However, the elastic force generating device using the solenoid S shown in FIG. 9 has advantages such as high speed and being able to be operated with a simple control mechanism, but requires a large current and increases weight. There is also a problem that requires a large space. It is also conceivable to use a pneumatic cylinder instead of the solenoid S. In that case, the space can be reduced, and there is an advantage that it can be operated by a simple control mechanism, but there is a problem that the speed is low and the resilience is reduced. Furthermore, although the apparatus using the elastic body E shown in FIG. 10 is high-speed, it requires a complicated mechanism and a control mechanism such as a force accumulation mechanism and a force release mechanism.

  On the other hand, the technique disclosed in Patent Document 1 does not have a means for accumulating a large force with a small motor, and is a mechanism that requires a large amount of power. Further, Patent Document 2 does not teach a means for accumulating a large force with a small motor.

  An object of the present invention is to provide an elastic force generating device capable of accumulating a large force with a small motor and generating a strong elastic force.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that an operating member having a cam follower part and an actuator rod part is pivotally supported by a fulcrum (joint) and is fixed at one end around an axis fixed to the housing. Is fixed to the housing and the other end is fixed to the actuator rod portion, and functions to generate an elastic force in the actuator rod portion by accumulating force by rotating the actuating member and releasing the restraint of the cam follower portion. A cam follower that winds the torsion spring and contacts the outer peripheral surface of the cam by rolling friction at the end of the cam follower rod is further formed. The normal line of the outer peripheral surface and the line segment connecting the fulcrum of the actuating member and the rotation axis of the cam follower are perpendicular or A Tamabachi force generating device and a rotary drive of the cam and said cam to release the restraint of the actuating member by the step portion and having an outer peripheral surface profile at an angle in the vicinity thereof.

  According to the second aspect of the present invention, at the top dead center (UD) of the cam rotation cycle, the direction of the force (F) transmitted from the outer peripheral surface of the cam to the cam follower and the rotation axis of the cam are 2. The elastic force generating device according to claim 1, wherein cams are arranged so as to coincide with each other.

  According to a third aspect of the present invention, there is provided a cam rotation state detecting means, and a control means for controlling to stop or start the cam rotation based on a signal from the detection means. The elastic force generating device according to claim 1 or claim 2.

  According to the present invention, a simple and small device configuration is used to apply a strong resilience to an object by an actuator by accumulating a large force in a torsion spring with a small motor and a small torque and releasing it instantaneously. Can do.

  When the invention according to claim 2 and claim 3 is used, the timing of the generation of the elastic force can be adjusted in a state where the torque for rotating the cam is zero, and a strong elastic force is targeted at the desired timing. Can be applied.

The elastic force generating apparatus of the present invention has the following main components. That is,
1) Mechanism for accumulating a large force in a torsion spring with a small motor 2) Mechanism for holding (locking) the force accumulated in the torsion spring 3) Mechanism for releasing the restraint of restoring the torsion spring and generating a strong resilience

  In the elastic force generating device of the present invention, in order to accumulate a large force in a torsion spring with a small motor, the cam (geared motor) rotates the cam and displaces the cam follower in contact with the cam outer peripheral surface by rolling friction. In the process of accumulating the force in the torsion spring, the line connecting the fulcrum of the actuating member and the rotation center of the cam follower and the normal of the outer peripheral surface of the cam at the point of action of the force are always perpendicular or near an angle. In addition, a cam profile is formed. Thus, in the process of accumulating the force from the cam rotated by the motor to the torsion spring via the cam follower and the cam follower rod, the direction of the force and the line segment connecting the fulcrum of the operating member and the rotation center of the cam follower are formed. The angle becomes 90 ° or an angle close thereto, and the rotational torque of the cam is accumulated in the torsion spring with the minimum force.

FIG. 1 shows an elastic force generating apparatus according to an embodiment of the present invention. In FIG. 1, 1 is an elastic force generating device, 2 is a housing, and a fulcrum (joint) 4 comprising a shaft 4-1 that pivotally supports a pair of operating members 3 is fixed. In this embodiment, as shown in FIGS. 1 and 2, the actuating member 3 has a substantially inverted L-shaped profile that is bent at a fulcrum (joint) 4. The operating member 3 includes an actuator rod 3-1 and a cam follower rod 3-2 with a fulcrum (joint) 4 as a boundary.

  As shown in FIGS. 1, 3, 4, 6, and 7, a cam follower 6 is rotatably disposed at the end of the cam follower rod 3-2. In this embodiment, the cam follower 6 is an outer race of a needle bearing that is pivotally supported at the ends of a pair of cam follower rods 3-2 as shown in FIG. The cam follower 6 is in contact with the outer peripheral surface of the cam 7 by rolling friction.

  On the other hand, a pair of torsion springs 5 are wound around the axis 4-1 of the fulcrum (joint) 4 in the operating member 3 between the inner wall surface of the housing 2 and the operating member 3 as shown in FIGS. Yes. As shown in FIGS. 3, 4, 6, and 7, one end of the pair of torsion springs 5 is fixed to the inner wall surface of the housing 2, and the other end is connected to the actuator rod 3-1 of the pair of operating members 3. It is fixed.

  Reference numeral 7 denotes a cam, which is fixed to a shaft 8 pivotally supported by the housing 2 as shown in FIG. Thus, as shown in FIGS. 1, 3, 4, 6, and 7, the outer peripheral surface of the cam 7 is in contact with the cam follower 6 by rolling friction. The cam 7 is rotationally driven by a geared motor 9 via a shaft 8.

  On the other hand, in this embodiment, as shown in FIGS. 1 and 7A and 7B, a limit switch cam 11 is fixed to the shaft 8 at one end. The limit switch 10 is turned on and off by the rotation of the cam 11.

Next, the force F required to displace the rotational axis of the cam follower 6 around the fulcrum 4 of the actuating member 3 when accumulating force in the torsion spring 5 by the rotation of the cam 7 will be described. here,
τ _s : Spring torque (resistance force)
F: Force (operating force) required to displace the rotational axis of the cam follower 6 around the fulcrum 4 of the operating member 3
X: distance between the center of the fulcrum 4 of the actuating member 3 (axial center of the shaft 4-1) and the acting point of the force F α: the center of the fulcrum 4 (axial center of the shaft 4-1) and the rotation center of the cam follower 6 Is the angle formed by the line n connecting the two and the direction of the force F, the following relationship is established between the magnitude of the operating force F and α.

Thus, when α = 90 °, F _min = τ _s / X, and F is minimum. Accordingly, when the actuating member 3 swings around the fulcrum 4, it passes through the rotation center of the cam follower 6 of the line segment n connecting the center of the fulcrum 4 (the axis of the shaft 4-1) and the rotation center of the cam follower 6. The profile of the cam 7 is determined so that the perpendicular and the tangent to the outer peripheral surface of the cam 7 at the point of application of the force F are always 90 ° or in the vicinity thereof. When the actuating member 3 swings around the fulcrum 4, a perpendicular line passing through the rotation center of the cam follower 6 of the line segment n connecting the center of the fulcrum 4 (axis center of the shaft 4-1) and the rotation center of the cam follower 6 When the point at which the tangent to the outer peripheral surface of the cam 7 is always 90 ° at the point of application of the force F is continued, the profile of the cam 7 shown in FIGS. 3, 4, 6 and 7 is obtained.

The output torque τ _m of the geared motor 9 necessary for accumulating the force in the torsion spring 5 becomes minimum when α = 90 °, and is expressed by the following equation.

ｄ：力Ｆの方向と、カム７の駆動軸８の軸心間の垂直距離（図３）

d: vertical distance between the direction of the force F and the axis of the drive shaft 8 of the cam 7 (FIG. 3)

Next, the relationship between the output torque τ _m of the geared motor 9 required for accumulating the force in the torsion spring 5, the geometrical relationship of the mechanism, and the static parameters is shown in the following equation.

Ｋ：ばね定数
Ｎ：捻りばね５の箇数
θ_ｍａｘ：捻りばね５に最大に力を蓄積したときのアクチュエータロッド３−１の角度（図４におけるアクチュエータロッド３−１の位置１と位置３とのなす角度）
θ_ｓ：捻りばね５に力を蓄積している途次におけるアクチュエータロッド３−１の角度、たとえば位置１と位置２とのなす角度
Ｌ：支点（ジョイント）４の中心（軸４−１の軸心）と、力Ｆの作用点間の距離（図４参照）
Ｈ：支点（ジョイント）４の中心（軸４−１の軸心）と、カム７の駆動軸（軸８）の軸心の鉛直方向距離（図４参照）

K: spring constant N: number of torsion springs 5 θ _max : angle of actuator rod 3-1 when force is accumulated in the torsion spring 5 to the maximum (position 1 and position 3 of actuator rod 3-1 in FIG. Angle)
θ _s : Angle of actuator rod 3-1 in the course of accumulating force in torsion spring 5, for example, angle formed by position 1 and position 2 L: Center of fulcrum (joint) 4 (axis of axis 4-1 Heart) and the distance between the application points of force F (see Fig. 4)
H: Vertical distance between the center of the fulcrum (joint) 4 (axis of the shaft 4-1) and the axis of the drive shaft of the cam 7 (axis 8) (see FIG. 4)

In the elastic force generating device of the present invention, while the force is accumulated in the torsion spring 5, the vertical distance d between the operating force F and the shaft center of the drive shaft (shaft 8) of the cam 7 shown in FIG. The torque τ _s and the operating force F of the torsion spring 5 increase and increase. During that time, the output torque τ _m of the geared motor 9 increases and decreases as shown in FIG. The results shown in FIG. 5 are obtained when H = 53.22 mm, N = 2, K = 3 N · m / deg, and θ _max = 22 °.

The important point of the result shown in FIG. 5 is that the more the force is accumulated in the torsion spring 5, the smaller the motor (geared motor 9) torque may be. In the elastic force generating device of the present invention, a large force can be accumulated in the torsion spring 5 with a small motor (geared motor 9) torque. When H = 53.22 mm, N = 2, K = 3 N · m / deg, θ _max = 22 °, a motor (geared motor) required to accumulate 132 N · m of torque in the pair of torsion springs 5 The torque of 9) was a peak torque of about 9 N · m, as shown in FIG.

FIG. 6 shows the geometric positional relationship of the actuating member 3 composed of the cam 7, the actuator rod 3-1 and the cam follower rod 3-2 in the process of accumulating the force in the torsion spring 5. 6A shows the state at the time when the cam 7 starts to rotate, FIG. 6B shows the intermediate stage of rotation of the cam 7, and FIG. 6C shows the final stage of rotation of the cam 7 (top dead center: UD ( upper dead point)). As shown in FIG. 6C, in the final stage of accumulation of the force on the torsion spring 5, the direction of the force F passes through the axis of the drive shaft (shaft 8) of the cam 7. When the drive of the motor (geared motor 9) is stopped in this state, the mechanism of the elastic force generating device is locked with the motor drive torque τ _m = 0, and the maximum force can be maintained on the torsion spring 5. In order to control the rotation of the cam 7 (drive of the geared motor 9), the limit switch 10 and the limit switch 10 are turned on and off as shown in FIGS. 1 and 7A and 7B. A switch cam 11 is provided.

  In this embodiment, the mechanical limit switch is used to control the rotation of the cam 7. However, the present invention is not limited to this, and an optical sensor or a rotation sensor such as a motor may be used. Of course you can.

  When the locked mechanism is released and the motor (geared motor 9) is further driven, the cam 7 rotates clockwise from the state shown in FIG. 6C, and the cam follower 6 abruptly cams 7 at the step portion immediately after. Is displaced around the center of the fulcrum (joint) 4 (the axis of the axis 4-1) in the axial direction of the drive shaft (axis 8). In other words, the force accumulated in the torsion spring 5 is released immediately after the restraint of the swing of the actuating member 3 is released, and a strong elastic force of the actuator rod 3-1 is generated.

As described above, the elastic force generating device of the present invention does not require a rotation sensor such as an encoder, and does not require motor rotation switching or any other special mechanism, and does not require a motor that rotates in one direction ( It is controlled only by the geared motor 9) and the limit switch 10. The control sequence is as follows.
1) The cam 7 is rotated by a motor (geared motor 9) so as to accumulate force in the torsion spring 5 until the limit switch 10 is turned on.
2) When the limit switch 10 is turned on, the cam 7 stops rotating and the mechanism is locked. When the lock is released and the cam 7 is rotated clockwise from the state of FIG. 6C by the motor (geared motor 9) in order to generate an elastic force to the actuator rod 3-1, at a desired timing, the cam follower Reference numeral 6 denotes a stepped portion of the cam 7, which is suddenly displaced around the center of the fulcrum (joint) 4 (the axis of the shaft 4-1) in the axial direction of the drive shaft (shaft 8) of the cam 7 (the limit switch 10 is turned off). ).
3) The cam 7 is rotated by the motor (geared motor 9) to accumulate force in the torsion spring 5 until the limit switch 10 is turned on again.
These states are shown in FIGS. 7 (a) and 7 (b). FIG. 7A shows a process of accumulating force in the torsion spring 5, and the limit switch 10 is OFF. When the force is fully accumulated in the torsion spring 5, the limit switch 10 is turned on as shown in FIG. 7B. There, the motor (geared motor 9) stops and the mechanism is locked. When the mechanism is unlocked from this state and the motor (geared motor 9) is driven to rotate clockwise as viewed in FIG. 6, the restraint state of the actuating member 3 (cam follower rod 3-2) is released, and the torsion spring 5 is restored. A strong elastic force is generated in the actuator rod 3-1 by the force.

  FIG. 8 shows an aspect when the present invention is applied to a kick device of a soccer robot 13. In this case, a panel is attached to the actuator rod 13-1.

  9 (a) and 9 (b) show an embodiment in which the elastic force generating device of the present invention is applied to a jump function of a robot foot. FIG. 9A shows the appearance of the robot foot, and FIG. 9B shows the elastic force generating device inside the foot. In this embodiment, a torsion spring 25 is wound around a fulcrum 24. The fulcrum 24 is fixed to the housing 22 and supports the actuator rod 23-1 so as to be rotatable.

  In the state shown in FIG. 9B, the force is fully accumulated in the torsion spring 25, a limit switch (not shown) is activated, and the rotation of the cam 27 is locked by the stop of the geared motor 29. Immediately before the step portion of the cam 27, the outer peripheral surface of the cam 27 and the cam follower 26 are in contact with each other. When the lock of the mechanism is released from this state and the cam 27 is rotated clockwise, the cam follower 26 is suddenly displaced at the stepped portion of the cam 27, and a strong elastic force is generated downward on the actuator 23-1. Then the robot jumps.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. The schematic diagram which shows the relationship between the segment n which connects the fulcrum of the operating member which consists of an actuator rod and a cam follower rod in this invention, and the rotation center of a cam follower, and the action direction of force. The longitudinal cross-sectional view which shows the relationship between the cam of an elastic force generating apparatus, an action member, and a torsion spring based on one Example of this invention The longitudinal cross-sectional view which shows the geometric parameter in each step of the force accumulation | storage of the elastic force generation apparatus based on one Example of this invention According to an embodiment of the present invention, the motor torque of the elastic force generating device and the force τ _s accumulated in the torsion spring, the vertical distance d between the rotation center of the cam follower and the rotation center of the cam, and the cam are transmitted to the cam follower. Graph showing the relationship between the magnitude of torque and motor drive torque τ _m It is a front view which shows the positional relationship of the actuating member which consists of the cam of the force accumulation process in the elastic force generation apparatus based on one Example of this invention, and an actuator rod and a cam follower rod, (a) is a force accumulation start time, ( (b) is a step in the middle, and (c) is a diagram showing a step in which full force accumulation is performed. It is a front view which shows the operating state of the limit switch for motor drive control and the cam for limit switches in the elastic force generator which concerns on one Example of this invention, (a) is a limit switch OFF, (b) is It is a figure which shows the time of a limit switch ON. The perspective view which shows the example which applied the resilience generating apparatus based on one Example of this invention to the kicker of a soccer robot It is a perspective view which shows the aspect which applied the elastic force generation apparatus based on the other Example of this invention to the jump mechanism of a robot leg part, (a) is an external view, (b) is an internal perspective view. It is the model which shows the conventional elastic force generation means, (a) is an example which makes force act on an actuator contrary to the elastic force application direction in the upper part of a fulcrum, (b) is the elastic force application direction in the lower part of a fulcrum. (C) is a figure which shows the example which applies the elastic force to a target directly by the solenoid S. Schematic diagram showing a conventional elastic force generating means using an elastic body E It is a front view which shows the conventional deposit | attachment removal apparatus of the belt surface using a cam and a spring, (a) is a detailed view, (b) is a general view.

Explanation of symbols

1 bullet repelling force generator 2 housing 3 actuating member 3-1 actuator rod 3-2 cam follower rod 4 fulcrum (joint)
4-1 shaft 5 torsion spring 6 cam follower 7 cam 8 shaft 9 geared motor 10 limit switch 11 limit switch cam 13 robot 13-1 actuator rod portion 22 housing 23-1 actuator rod 24 fulcrum 25 torsion spring 26 cam follower 27 cam 28 shaft 29 geared motor 101 conveyor belt 102 head pulley 104 driving sprocket wheel 105 driven sprocket wheel 106 chain 107 idler 108 motor 109 hopper 110 camshaft 111 cam 115 rod 116 roller 117 spring receiver 118 rebound spring 119 case 119a stopper 120 hammer head S solenoid J fulcrum A Actuator O Repulsive force target E Elastic body

Claims (3)

  A shaft (4-1) that pivots an operating member (3) having a cam follower part (3-2) and an actuator rod part (3-1) at a fulcrum (joint) (4) and is fixed to the housing (2). ), One end thereof is fixed to the housing (2) and the other end is fixed to the actuator rod portion (3-1). The force is accumulated by the rotation of the actuating member (3), and the cam follower portion (3 -2) is wound around a torsion spring (5) that functions to generate an elastic force in the actuator rod part (3-1) by releasing the restraint, and rolls to the end of the cam follower rod (3-2). The cam follower (6) that contacts the outer peripheral surface of the cam (7) is formed by friction, and the cam outer portion at the point of application of the force (F) transmitted from the outer peripheral surface of the cam to the cam follower by the rotation of the cam (7). The normal line of the surface and the line segment connecting the fulcrum (4) of the actuating member (3) and the rotational axis of the cam follower (6) have a profile that is perpendicular or near the angle, and the actuating member ( 3. An elastic force generating device comprising a cam (7) for releasing the restraint of 3) and a rotation driving device (9) for the cam.   At the top dead center (UD) of the rotation cycle of the cam (7), the direction of the force (F) transmitted from the outer peripheral surface of the cam (7) to the cam follower (6) and the rotation axis of the cam (7) The elastic force generating device according to claim 1, wherein cams (7) are arranged so as to coincide with each other. A detecting means (10) for rotating the cam (7) is provided, and a control means for controlling to stop or start the turning of the cam (7) based on a signal from the detecting means is provided. The elastic force generating apparatus according to claim 1 or 2.

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