Rotary tool

Abstract

Provided is a compact rotary tool. A rotary tool comprises: a first mechanism capable of applying a first load to a clutch part; and a second mechanism capable of applying a second load to the clutch part.

Description

rotary tools

[0001] The present disclosure relates to rotary tools.

[0002] Patent Document 1 discloses a torque driver that can perform tightening with a desired tightening torque. The torque driver disclosed in Patent Document 1 has a coil spring that biases the main shaft toward the base end of the cylindrical portion.

[0003] Japanese Patent Application Publication No. 2018-134713

[0004] a first mechanism capable of applying a first load to the clutch unit; and a second mechanism capable of applying a second load to the clutch unit. The second mechanism is configured to apply a first load to the clutch unit and to transmit a second load to the clutch unit. The second mechanism is configured to apply a first load to the clutch unit and to transmit a second load to the clutch unit. The second mechanism is configured to apply a first load to the clutch unit and to transmit a second load to the clutch unit.

[0005] FIG. 1 is a cross-sectional view showing the configuration of a rotary tool according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along III-III of FIG. 1. FIG. 3 is an exploded perspective view and a perspective view of a switching unit. FIG. 4 is a view explaining the operating mechanism of the switching unit in a first mode. FIG. 5 is a view explaining the operating mechanism of the switching unit in a second mode. FIG. 6 is a cross-sectional view taken along VII-VII of FIG. 1. FIG. 7 is a cross-sectional view taken along VIII-VIII of FIG. 1. FIG. 7 is a cross-sectional view explaining the operating mechanism of the rotary tool in a first mode. FIG. 8 is a view explaining the operating mechanism of the rotary tool when transitioning to idling. FIG. 9 is a graph showing the relationship between set torque and spring load. FIG. 10 is a cross-sectional view showing the configuration of a rotary tool according to a second embodiment of the present disclosure.

[0006] In the torque driver disclosed in Patent Document 1, in order to increase the tightening torque, it is necessary to increase the maximum amount of compression of the coil spring, in other words, to increase the size of the coil spring. Therefore, in the torque driver disclosed in Patent Document 1, there is a risk that the torque driver will become larger as the tightening torque increases.

[0007] On the other hand, as described below, according to one aspect of the present disclosure, a small rotary tool can be realized.

[0008] An embodiment of the present disclosure will be described. For convenience of explanation, components having the same functions as components previously described will be denoted by the same reference numerals, and their explanations may not be repeated. "Parallel" does not mean strictly parallel, but includes an error of about ±5°. "Perpendicular" does not mean strictly perpendicular, but includes an error of ±5°.

[0009] 1 and 2 are cross-sectional views showing a configuration of a rotary tool 101 according to a first embodiment of the present disclosure. Each of FIGS. 1 and 2 is a cross-section passing through an axis A and parallel to the axis A.

[0010] The rotary tool 101 may have a shape extending from the tip to the rear end along the axis A. An example of such a shape is a rod shape. The rotary tool 101 may include a tip portion 1, a drive unit 2, a gripping portion 3, a switching unit 4, a clutch unit 5, a first mechanism 6, and a second mechanism 7. The first mechanism 6 may include an adjustment mechanism 8, a first elastic body 9, and a first support member 10. The second mechanism 7 may include a second elastic body 11 and a second support member 12. The rotary tool 101 may also have a housing 13, and the drive unit 2, the switching unit 4, the clutch unit 5, the first mechanism 6, and the second mechanism 7 may be located inside the housing 13.

[0011] The tip portion 1 is located on the tip side. The tip portion 1 is a portion that comes into contact with a screw, for example, when performing an operation of fastening or loosening a screw. The tip portion 1 is rotatable around an axis A. The axis A may be located at the center of the rotary tool 101 when viewed in the longitudinal direction of the rotary tool 101.

[0012] The drive unit 2 generates a first rotational drive force for rotating the tip portion 1. The first rotational drive force may be a mechanical and / or electrical drive force generated by at least one component provided in the drive unit 2. As the at least one component, the drive unit 2 may have a battery cell 51, a motor 52 that operates using the battery cell 51 as a power source, and a gear unit 53 that transmits the force generated by the motor 52.

[0013] The grip portion 3 receives an input of a second rotational driving force for rotating the tip portion 1. The grip portion 3 is located closer to the rear end than the tip portion 1. The grip portion 3 may receive an input of the second rotational driving force from outside the rotary tool 101. The second rotational driving force may be a driving force generated when a user of the rotary tool 101 grips the grip portion 3 and manually turns the rotary tool 101.

[0014] In the embodiment of the present disclosure, the first rotational driving force is an electric driving force generated by the motor 52 or the like, and the second rotational driving force is a driving force generated by manually rotating the rotary tool 101. Therefore, in the first mode in which the first rotational driving force is transmitted from the drive unit 2 to the tip end portion 1, the tip end portion 1 rotates automatically. In the second mode in which the second rotational driving force is transmitted from the grip unit 3 to the tip end portion 1, the tip end portion 1 rotates manually.

[0015] The switching unit 4 switches between a first mode in which a first rotational driving force is transmitted from the driving unit 2 to the tip portion 1 and a second mode in which a second rotational driving force is transmitted from the gripping unit 3 to the tip portion 1 .

[0016] Fig. 3 is a cross-sectional view taken along line III-III in Fig. 1. Fig. 3 is a cross-section perpendicular to axis A. Fig. 4 is an exploded perspective view and a perspective view of the switching unit 4. In Fig. 4, the exploded perspective view of the switching unit 4 is denoted by reference numeral 1001, and the perspective view of the switching unit 4 is denoted by reference numeral 1002.

[0017] The switching unit 4 has a carrier 54, a lock pin 55, a lock cam 56, and a lock ring 57. The carrier 54 transmits driving force mainly in the first mode. The lock pin 55 is fitted into the carrier 54. The lock cam 56 is fitted into the carrier 54 and transmits driving force mainly in the second mode. The carrier 54 is fitted into the lock ring 57.

[0018] 5 is a diagram illustrating the operation mechanism of the switching unit 4 in the first mode. This operation mechanism has a first stage and a second stage, and the diagram showing the first stage is given the reference numeral 1003, and the diagram showing the second stage is given the reference numeral 1004.

[0019] In the first mode, the switching unit 4 performs the following operation. In the first stage, when the motor 52 rotates, the carrier 54 begins to rotate in direction D1 around the axis A. In the second stage, the carrier 54 and the lock pin 55 come into contact with each other at contact point C1, and at almost the same time, the carrier 54 and the lock cam 56 come into contact with each other at contact point C2. As a result, the positional relationship between the lock pin 55 and the lock cam 56 does not change, and the lock cam 56 rotates around the axis A.

[0020] 6 is a diagram illustrating the operation mechanism of the switching unit 4 in the second mode. This operation mechanism has a first stage, a second stage, and a third stage, and the diagram showing the first stage is given the reference numeral 1005, the diagram showing the second stage is given the reference numeral 1006, and the diagram showing the third stage is given the reference numeral 1007.

[0021] In the second mode, the switching unit 4 performs the following operation. In a first stage, the carrier 54, the lock pin 55, the lock cam 56, and the lock ring 57 rotate in direction D2 around the axis A. In a second stage, the carrier 54, the lock pin 55, and the lock ring 57 continue to rotate in direction D2, but the lock cam 56 is less likely to rotate in direction D2 than the carrier 54, the lock pin 55, and the lock ring 57 due to, for example, resistance from screw tightening. As a result, the carrier 54 and the lock cam 56 come into contact at a contact point C3. In a third stage, the carrier 54 and the lock pin 55 come into contact, but before that, the lock pin 55 and the lock cam 56 interfere with each other at an interference point F, so the carrier 54, the lock pin 55, and the lock cam 56 rotate together around the axis A or cannot rotate relative to each other.

[0022] The clutch unit 5 is interposed in the transmission path of the second rotational driving force in the second mode. The clutch unit 5 may be interposed in the transmission path of the first rotational driving force in the first mode. The clutch unit 5 limits the transmission of the second rotational driving force to the tip end 1 when the second rotational driving force exceeds a predetermined magnitude. The clutch unit 5 may have a first member 58 and a second member 59. In an embodiment of the present disclosure, the first member 58 and the second member 59 may be interposed in the transmission path of the first rotational driving force and / or the second driving force. The first member 58 and the second member 59 may each have a substantially disk-shaped bottom and a substantially columnar or cylindrical protrusion protruding from the center of the bottom. The first member 58 and the second member 59 are located inside the housing 13 of the rotary tool 101. In an embodiment of the present disclosure, the housing 13 has a grip portion 3 and a housing portion 60. The first member 58 and the second member 59 are positioned in this order from the tip side along the axis A. The tip portion 1 can rotate as the first member 58 and / or the second member 59 rotate around the axis A.

[0023] The rotary tool 101 may have a first biasing portion 61 and a second biasing portion 62. The first biasing portion 61 is in point or line contact with the clutch portion 5. The first biasing portion 61 can bias the clutch portion 5 toward the rear end. The first biasing portion 61 biases the clutch portion 5 toward the rear end by biasing the first member 58 from the tip side in a point-like or line-like manner. The number of points or lines at which the first biasing portion 61 contacts the clutch portion 5 is not limited to one and may be two or more. The clutch portion 5 may have a washer 63 located between the first member 58 and the first biasing portion 61. In this case, the first biasing portion 61 is in point or line contact with the washer 63. In the first biasing portion 61, a first contact member 64 may be in point or line contact with the clutch portion 5.

[0024] An example of the first urging portion 61 that comes into point contact with the clutch portion 5 is one that includes a thrust bearing or at least one steel ball. A first urging portion 61 that includes a thrust bearing is easier to assemble than a first urging portion 61 that includes at least one steel ball, because rolling elements such as balls are located in a cage. An example of the first urging portion 61 that comes into line contact with the clutch portion 5 is one that includes a needle bearing. Because a needle bearing has a shorter length in the direction of extension of the axis A than both a thrust bearing and a steel ball, the length of the first urging portion 61 that includes a needle bearing can be reduced in the direction of extension of the axis A of the rotary tool 101.

[0025] The "point contact" in this embodiment is not limited to point contact in the strict sense. The "point contact" in this embodiment may be point contact from a macroscopic perspective, and for example, it is sufficient that at least one of the contact portion between the clutch portion 5 and the first biasing portion 61 and the contact portion between the first biasing portion 61 and the clutch portion 5 is a sphere and they are in contact with each other. A slight surface contact from a microscopic perspective due to deformation caused by friction or the like that occurs between the clutch portion 5 and the first biasing portion 61 is allowed as "point contact" in this embodiment.

[0026] Similarly, "line contact" in this embodiment is not limited to line contact in the strict sense. "Line contact" in this embodiment may be line contact from a macroscopic perspective, and for example, it is sufficient that at least one of the contact portion of the clutch portion 5 with the first urging portion 61 and the contact portion of the first urging portion 61 with the clutch portion 5 is cylindrical and they are in contact with each other. Slight surface contact from a microscopic perspective due to deformation caused by friction or the like that occurs between the clutch portion 5 and the first urging portion 61 is allowed as "line contact" in this embodiment.

[0027] The clutch unit 5 may have a guide groove 73 at a portion that makes point or line contact with the first biasing unit 61. The guide groove 73 may guide the first contact member 64. More specifically, the guide groove 73 may guide the movement of the first contact member 64 in the circumferential direction. In an embodiment of the present disclosure, the guide groove 73 is formed circumferentially on a member (washer 63) that contacts the first contact member 64. In such a case, the first contact member 64 can be guided, reducing the risk of the first contact member 64 excessively shifting in the radial direction of a circle centered on the axis A. The radius of curvature of the recess of the guide groove 73 may be larger than the radius of curvature of the first contact member 64. In such a case, the resistance between the clutch unit 5 and the first biasing unit 61 is likely to be small. The radius of curvature of the recess of the guide groove 73 may be measured in a cross section that includes the recess and the axis A and is parallel to the axis A. For the guide groove 73, see also FIG. 10 , which will be described later.

[0028] The first contact member 64 and the structure 65 may be in point contact or line contact. The structure 65 may be, for example, annular in shape. In such a case, the resistance between the first contact member 64 and the structure 65 is reduced. The structure 65 may be provided with the above-mentioned guide groove in the portion that makes point contact or line contact with the first contact member 64.

[0029] The rotary tool 101 may be used to tighten the screw 102. The screw 102 is not particularly limited as long as it is intended for screwing, but an example of the screw 102 is a screw for fixing a cutting insert to a pocket of a cutting tool.

[0030] When using the rotary tool 101 to tighten the screw 102, the first mode and the second mode may be performed in this order. In the first mode, the tip 1 is rotated according to a first rotational driving force to tighten the screw 102. In the second mode, the tip 1 is rotated according to a second rotational driving force to further tighten the screw 102.

[0031] As the screw 102 is tightened in the second mode, a state in which the screw 102 is tightened to a predetermined tightness is reached. In this state, if the second rotational driving force is small enough that the clutch unit 5 does not restrict the transmission of the second rotational driving force to the tip end portion 1, the screw 102 stops the rotation of the rotary tool 101, preventing the rotary tool 101 from further tightening the screw 102. In this state, if the second rotational driving force is large enough that the clutch unit 5 restricts the transmission of the second rotational driving force to the tip end portion 1, excessive tightening of the screw 102 is avoided, resulting in idling, in which the gripping unit 3 rotates without the tip end portion 1 rotating. The predetermined magnitude of the second rotational driving force, which controls whether the clutch unit 5 restricts the transmission of the second rotational driving force to the tip end portion 1, can be said to correspond to the boundary between whether idling occurs and whether idling occurs. The predetermined magnitude of the second rotational driving force may correspond to an inherent torque value of the rotary tool 101, or may correspond to a torque value adjusted, for example, by a torque management unit (adjustment mechanism 8) or the like.

[0032] Figure 7 is a cross-sectional view taken along line VII-VII in Figure 1. The first member 58 may have a plurality of balls 66 arranged in an annular shape at a position facing the second member 59. In the cross-section taken along line VII-VII in Figure 1, the plurality of balls 66 may be, for example, six balls 66 arranged at 60° intervals. Figure 7 is a cross-section perpendicular to the axis A.

[0033] 8 is a cross-sectional view taken along line VIII-VIII in FIG. 1. The second member 59 may have a plurality of recesses 67 arranged in an annular shape at a position facing the first member 58. In the cross-section taken along line VIII-VIII in FIG. 1, the plurality of recesses 67 may be, for example, six recesses 67 arranged at 60° intervals. The plurality of balls 66 and the plurality of recesses 67 may be arranged so that one recess 67 faces one ball 66 at a time. The recess 67 may have a conical shape whose inner diameter decreases from the front end side to the rear end side.

[0034] 9 is a cross-sectional view illustrating the operating mechanism of the rotary tool 101 in the first mode. The first rotational driving force is transmitted in the order of the drive unit 2, the clutch unit 5, and the tip end portion 1. In the first mode, the rotary tool 101 operates according to the following operating mechanism.

[0035] The ball 66 fits into the recess 67. This allows the first member 58 and the second member 59 to rotate integrally around the axis A; in other words, the second member 59 does not rotate around the axis A relative to the first member 58. Therefore, the clutch portion 5 can transmit the first rotational driving force to the tip end portion 1, which rotates around the axis A and tightens the screw 102.

[0036] In the first mode, whether or not the first member 58, the second member 59, the third member 68, the washer 63, the ball 66, the first contact member 64, the second contact member 69, the first elastic body 9, the second elastic body 11, and the housing 13 rotate around the axis A as seen by the user of the rotary tool 101 is summarized below. Here, whether or not the first member 58, the second member 59, the third member 68, the washer 63, the ball 66, the first contact member 64, the second contact member 69, the first elastic body 9, the second elastic body 11, and the housing 13 rotate around the axis A as seen by the user of the rotary tool 101 refers to whether or not each member rotates around the axis A relatively from the user's viewpoint, and does not necessarily mean that the user can actually confirm whether or not each member is rotating from outside the rotary tool 101. The same applies to the second mode, which will be described later.

[0037] (In the case of the first mode) First member 58: Rotates Second member 59: Rotates Third member 68: Does not rotate Washer 63: Rotates Ball 66: Rotates First contact member 64: Rotates slightly or does not rotate Second contact member 69: Rotates slightly or does not rotate First elastic body 9: Does not rotate Second elastic body 11: Does not rotate Housing 13: Does not rotate The amount of rotation of the washer 63 may be less than the amount of rotation of the first member 58 or may be more than the amount of rotation of the first contact member 64. The amount of rotation means the number of rotations per unit time. The third member 68 and the second contact member 69 may each be provided to the second biasing portion 62.

[0038] The operating mechanism of the rotary tool 101 in the second mode will be described. The second rotational driving force is transmitted in this order to the gripping portion 3, the gear unit 53, the clutch portion 5, and the tip portion 1. In the second mode, the rotary tool 101 operates according to the following operating mechanism.

[0039] In the second mode where no freewheeling occurs, the ball 66 remains fitted in the recess 67, and the second member 59 does not rotate around the axis A relative to the first member 58. Therefore, the clutch portion 5 can transmit the second rotational driving force to the tip portion 1.

[0040] In the second mode where no freewheeling occurs, whether the first member 58, the second member 59, the third member 68, the washer 63, the ball 66, the first contact member 64, the second contact member 69, the first elastic body 9, the second elastic body 11, and the housing 13 rotate around the axis A as seen by the user of the rotary tool 101 is summarized below.

[0041] (In the second mode where no freewheeling occurs) First member 58: Rotating second member 59: Rotating third member 68: Rotating washer 63: Rotating ball 66: Rotating first contact member 64: Rotating second contact member 69: Rotating first elastic body 9: Rotating second elastic body 11: Rotating housing 13: Rotating first member 58, second member 59, third member 68, washer 63, ball 66, first contact member 64, second contact member 69, first elastic body 9, second elastic body 11, and housing 13 may rotate together.

[0042] Figure 10 is a diagram illustrating the operating mechanism of the rotary tool 101 during transition to idling. Figure 10 shows four cross sections taken along the X-X line in Figure 7: a free state indicated by reference numeral 1008, a torque transmission state indicated by reference numeral 1009, a clutch actuation start state indicated by reference numeral 1010, and a transition state to the next clutch hole indicated by reference numeral 1011. From the start of transition to idling, the process progresses in the order of the free state, torque transmission state, clutch actuation start state, and the transition state to the next clutch hole, until the transition to idling is completed. Figure 10 is a cross section parallel to the axis A.

[0043] When slippage occurs in the second mode, the force that tends to rotate the second member 59 about the axis A relative to the first member 58 causes the ball 66 to come out of the recess 67, and the second member 59 rotates about the axis A relative to the first member 58. Therefore, it is difficult for the clutch unit 5 to transmit the second rotational driving force to the tip end portion 1. The second biasing unit 62, the biasing structure 70, and the second member 59 rotate together with the gripping portion 3. The biasing structure 70 may have the first elastic body 9, and a structure 65 that is positioned between the first contact member 64 and the first elastic body 9 and biases the first contact member 64 toward the rear end.

[0044] In the second mode where freewheeling occurs, whether the first member 58, the second member 59, the third member 68, the washer 63, the ball 66, the first contact member 64, the second contact member 69, the first elastic body 9, the second elastic body 11, and the housing 13 rotate around the axis A as seen by the user of the rotary tool 101 is summarized below.

[0045] (When freewheeling occurs in the second mode) First member 58: Does not rotate Second member 59: Rotates Third member 68: Rotates Washer 63: Does not rotate Ball 66: Does not rotate First contact member 64: Rotates slightly or does not rotate Second contact member 69: Rotates First elastic body 9: Rotates Second elastic body 11: Rotates Housing 13: Rotates From the above, it can be seen that in the rotary tool 101, when freewheeling occurs, the second member 59 rotates around axis A relative to the first member 58 in response to the input of the second rotational driving force.

[0046] In both the first mode and the second mode, the first biasing portion 61 is in point contact or line contact with the clutch portion 5, and therefore the frictional force generated in the first biasing portion 61 is small.

[0047] According to the rotary tool 101, the contact area between the clutch portion 5 and the first biasing portion 61 is small, so that the frictional force generated in the first biasing portion 61 can be reduced, and the deterioration rate of the first biasing portion 61 can be slowed, thereby enabling a longer life. In addition, as the frictional force is reduced, the loss of the first rotational driving force in the first biasing portion 61 is small, so that the tip portion 1 can be sufficiently rotated with a small first rotational driving force, thereby enabling low power consumption of the rotary tool 101 and, in particular, miniaturization of the drive portion 2.

[0048] The second urging portion 62 is in point contact or line contact with the clutch portion 5. The second urging portion 62 is capable of urging the clutch portion 5 toward the tip. The number of points or lines at which the second urging portion 62 contacts the clutch portion 5 is not limited to one, and may be two or more. In the second urging portion 62, the second contact member 69 may play a role in making point contact or line contact with the clutch portion 5.

[0049] An example of the second urging portion 62 that comes into point contact with the clutch portion 5 is one that includes a thrust bearing or at least one steel ball. A second urging portion 62 that includes a thrust bearing is easier to assemble than a second urging portion 62 that includes at least one steel ball, because rolling elements such as balls are located in a cage. An example of the second urging portion 62 that comes into line contact with the clutch portion 5 is one that includes a needle bearing. Because a needle bearing has a shorter length in the direction of extension of the axis A than both a thrust bearing and a steel ball, the length of the second urging portion 62 that includes a needle bearing can be reduced in the direction of extension of the axis A of the rotary tool 101.

[0050] In both the first mode and the second mode, the second biasing portion 62 is in point contact or line contact with the clutch portion 5, and therefore the frictional force generated in the second biasing portion 62 is small.

[0051] According to the rotary tool 101, the contact area between the clutch portion 5 and the second urging portion 62 is small, so that the frictional force generated in the second urging portion 62 can be reduced, and the deterioration rate of the second urging portion 62 can be slowed, thereby enabling a longer life. In addition, as the frictional force is reduced, the loss of the first rotational driving force in the second urging portion 62 is small, so that the tip portion 1 can be sufficiently rotated with a small first rotational driving force, thereby enabling low power consumption of the rotary tool 101 and, in particular, miniaturization of the drive portion 2.

[0052] The first mechanism 6 is capable of applying a first load to the clutch portion 5. The direction in which the first mechanism 6 applies the first load may be a first direction G1 that is a direction along the axis A. The first direction G1 may be a direction parallel to the axis A. The second mechanism 7 is capable of applying a second load to the clutch portion 5. The direction in which the second mechanism 7 applies the second load may be the first direction G1. Here, in this embodiment, the first load and the second load affect the predetermined magnitude of the second rotational driving force that is used to control whether the clutch portion 5 limits the transmission of the second rotational driving force to the tip portion 1. More specifically, the total magnitude of the first load and the second load affects the likelihood of slippage in the clutch portion 5.

[0053] In both cases where the first elastic body 9 is a spring and where the second elastic body 11 is a spring, the load may be a spring load as defined in Japanese Industrial Standards JIS B0103:2015. The spring load may be a load applied to or generated from the spring. The unit of the load may be N (Newton) or may be a unit that can be converted to N.

[0054] The first load and the second load may be different from each other. Furthermore, the first elastic body 9 and the second elastic body 11 may have different sizes.

[0055] According to the rotary tool 101, the first mechanism 6 and the second mechanism 7 each apply a load to the clutch portion 5. This eliminates the need to provide a large mechanism in the rotary tool 101 for applying a load to the clutch portion 5. This allows the rotary tool 101 to be made smaller.

[0056] The adjustment mechanism 8 receives an adjustment operation for adjusting the first load. The first elastic body 9 extends in a first direction G1 along the axis A. The first support member 10 supports an end of the first elastic body 9 opposite the clutch portion 5. The first support member 10 may be movable by an adjustment operation for adjusting the first load.

[0057] The adjustment mechanism 8 has an adjustment cap 71 and an interlocking member 72 that interlocks with the adjustment cap 71. When the adjustment cap 71 is turned in the second direction G2, the interlocking member 72 rotates in the second direction G2 in synchronization with the adjustment cap 71. The interlocking member 72 is a so-called male screw.

[0058] The first support member 10 has a so-called female screw that screws into the interlocking member 72. As the interlocking member 72 rotates in the second direction G2, the first support member 10 can move in the direction in which the thread of the interlocking member 72 extends, i.e., in the first direction G1. The closer the position of the first support member 10 to the clutch unit 5 in the first direction G1, the greater the force that the first support member 10 applies to the first elastic body 9, and therefore the greater the force that the first elastic body 9 applies to the clutch unit 5. The first load corresponds to the force that the first elastic body 9 applies to the clutch unit 5.

[0059] The above mechanism allows for an adjustment operation to be performed to adjust the first load, which is received by the adjustment mechanism 8. It can also be said that the first load is variable by this adjustment operation.

[0060] The second load may be constant. The second elastic body 11 extends in a first direction G1 along the axis A. The second support member 12 supports an end of the second elastic body 11 opposite to the clutch unit 5. The second support member 12 may be fixed to a housing 13 of the rotary tool 101.

[0061] The term "constant second load" may mean that the second load does not change due to an adjustment operation for adjusting the first load. Specifically, the term "constant second load" may mean that the second load does not change even when an operator performs an adjustment operation for adjusting the first load via the adjustment mechanism 8. "Constant" does not mean "constant" in the strict sense, but rather allows for slight changes in the second load due to, for example, slight expansion and contraction of the second elastic body 11 due to the engagement of the clutch portion 5.

[0062] In an embodiment of the present disclosure, the second support member 12 may be fixed to the housing 13 of the rotary tool 101. Here, being fixed to the housing 13 of the rotary tool 101 means either that the second support member 12 does not move relative to the housing 13 even when an adjustment operation to adjust the first load is performed, or that the second support member 12 is physically fixed to the housing 13 (casing 60) as shown in a second embodiment of the present disclosure described below. When the second support member 12 is physically fixed to the housing 13 (casing 60), the risk of friction between the adjustment mechanism 8 and the second support member 12 can be reduced, as described below. The second support member 12 may be fixed to the grip portion 3 instead of the casing 60. The second support member 12 may be composed of multiple parts.

[0063] The first elastic body 9 and the second elastic body 11 may each be located on the distal end side of the clutch portion 5. An example of each of the first elastic body 9 and the second elastic body 11 is a spring. Examples of the spring include a coil spring and a wave spring.

[0064] Fig. 11 is a graph showing the relationship between set torque and spring load. In Fig. 11, the horizontal axis shows set torque in units of Nm. In Fig. 11, the vertical axis shows spring load in units of N. Here, the set torque may correspond to the likelihood of slippage occurring in the clutch section 5, as described above.

[0065] The characteristic T1 in Fig. 11 corresponds to the first load. The characteristic T2 in Fig. 11 corresponds to the second load. The characteristic TA in Fig. 11 corresponds to the sum of the first load and the second load. The explanation with reference to Fig. 11 applies to the case where the first elastic body 9 and the second elastic body 11 are each a spring.

[0066] Here, if a single spring is used to apply a predetermined load to the clutch unit 5, a large load would require increasing the linearity or diameter of the spring, resulting in a larger overall configuration. However, in the embodiment of the present disclosure, the configuration is made up of multiple springs, so even when the predetermined load is applied to the clutch unit 5, the overall configuration can be made smaller than if a single spring were used. More specifically, the configuration made up of multiple springs can be fitted into a limited space by carefully arranging the springs, thereby making the overall configuration smaller than if a single spring were used. Here, the term "spring" may refer to a mechanism (first mechanism 6, second mechanism 7) or an elastic body (first elastic body 9, second elastic body 11).

[0067] In the embodiment of the present disclosure, the second load is constant because the second elastic body 11 does not accept an adjustment operation for adjusting the load, unlike the first elastic body 9. Therefore, in order to adjust the spring load applied to the clutch portion (the spring load of the characteristic TA in FIG. 11 ), it is sufficient to adjust the load of the first load (the characteristic T1 in FIG. 11 ).

[0068] 11 shows an example in which the set torque range of the rotary tool 101 is 4.0 Nm to 7.5 Nm. It may be interpreted that FIG. 1 shows the case in which the set torque is 4.0 Nm, and FIG. 2 shows the case in which the set torque is 7.5 Nm. For example, even if the set torque range of the rotary tool 101 is 8 Nm to 12 Nm or 12 Nm to 16 Nm, a small rotary tool 101 can be realized by applying the first mechanism 6 having the first elastic body 9 and the second mechanism 7 having the second elastic body 11.

[0069] In the first direction G1 along the axis A, the first elastic body 9 may be longer than the second elastic body 11. In the rotary tool 101, one of the first elastic body 9 and the second elastic body 11 may be located inside the other of the first elastic body 9 and the second elastic body 11 in a plane S perpendicular to the axis A. In FIG. 1 , the second elastic body 11 is located inside the first elastic body 9. This allows the size of the mechanism capable of applying a load to the clutch portion 5 in the first direction G1 to be reduced, thereby realizing a compact rotary tool 101.

[0070] Furthermore, in a cross section passing through the axis A and parallel to the axis A, one of the first elastic body 9 and the second elastic body 11 may be located closer to the axis A than the other of the first elastic body 9 and the second elastic body 11. More specifically, the first elastic body 9 and the second elastic body 11 may be located parallel to each other. Here, "located parallel" refers to a case where the first elastic body 9 and the second elastic body 11 are not misaligned in a direction parallel to the axis A. If the lengths of the first elastic body 9 and the second elastic body 11 are different in a direction parallel to the axis A, the first elastic body 9 and the second elastic body 11 may be located parallel to each other if the shorter elastic body is located within the range of the longer elastic body. In such a case, the size of the mechanism capable of applying a load to the clutch portion 5 in the first direction G1 can be reduced, thereby realizing a compact rotary tool 101.

[0071] The first mechanism 6 and the second mechanism 7 may each be located closer to the tip end than the clutch unit 5. The first mechanism 6 and the second mechanism 7 may each be located along the first direction G1 parallel to the axis A. This allows the rotary tool 101 to be made smaller.

[0072] The second mechanism 7 may be in contact with the first mechanism 6. The second support member 12 may be in contact with the adjustment mechanism 8. This can contribute to reducing the manufacturing cost of the rotary tool 101.

[0073] 12 is a cross-sectional view showing the configuration of a rotary tool 101 according to a second embodiment of the present disclosure.

[0074] The second mechanism 7 may be spaced apart from the first mechanism 6. This can reduce the risk of friction occurring between the first mechanism 6 and the second mechanism 7. The second support member 12 may be spaced apart from the adjustment mechanism 8. This can reduce the risk of friction occurring between the adjustment mechanism 8 and the second support member 12. More specifically, of the friction involved in the adjustment mechanism 8, the influence of friction due to the second load can be reduced.

[0075] By reducing the risk of such friction, the adjustment cap 71 can be turned with a lighter force, facilitating fine adjustment of the first load. Therefore, the rotary tool 101 can be realized with high operability.

[0076] Although the embodiment of the present disclosure refers to the rotary tool 101 having a first mode and a second mode, the present disclosure is not limited thereto. For example, a rotary tool 101 having only the first mode or only the second mode may have the same configuration as the embodiment of the present disclosure. Furthermore, the embodiment of the present disclosure refers to the relationship between the loads (first load and second load) applied by the first mechanism and the second mechanism to the clutch unit 5 and the set torque (likelihood of slippage) in the second mode, i.e., the manual mode, but the present disclosure is not limited thereto. For example, the relationship between the loads (first load and second load) applied by the first mechanism and the second mechanism to the clutch unit 5 and the set torque (likelihood of slippage) may exist in the first mode, i.e., the automatic mode, and the final degree of screw tightening may be adjustable in the first mode. From the above, it can be seen that the problem that the above-mentioned invention aims to solve can be solved by a rotary tool 101 that is at least a rotary tool 101 having a shape extending from the tip to the rear end along an axis, and that is equipped with a tip portion 1 located on the tip side and rotatable around the axis, a clutch portion 5 that is interposed in the transmission path of the rotational driving force for rotating the tip portion 1 and that limits the transmission of the rotational driving force to the tip portion 1 when the rotational driving force exceeds a predetermined magnitude, a first mechanism 6 that is capable of applying a first load to the clutch portion 5, and a second mechanism 7 that is capable of applying a second load to the clutch portion.

[0077] [Summary] A rotary tool according to a first aspect of the present disclosure is a rotary tool having a shape extending from a tip to a rear end along an axis, and including: a tip portion located on the tip side and rotatable around the axis; a drive unit configured to generate a first rotational driving force for rotating the tip portion; a gripper unit configured to receive an input of a second rotational driving force for rotating the tip portion and located closer to the rear end than the tip portion; a switch unit configured to switch between a first mode in which the first rotational driving force is transmitted from the drive unit to the tip portion and a second mode in which the second rotational driving force is transmitted from the gripper unit to the tip portion; a clutch unit configured to, in the second mode, limit transmission of the second rotational driving force to the tip portion when the second rotational driving force exceeds a predetermined magnitude; a first mechanism configured to apply a first load to the clutch unit; and a second mechanism configured to apply a second load to the clutch unit.

[0078] A rotary tool according to a second aspect of the present disclosure is related to the first aspect, wherein the first mechanism includes an adjustment mechanism that accepts an adjustment operation for adjusting the first load.

[0079] A rotary tool according to aspect 3 of the present disclosure is the same as in aspect 2, wherein the first mechanism has a first elastic body extending in a direction along the axis and a first support member supporting the end of the first elastic body opposite the clutch portion, and the first support member is movable by the adjustment operation.

[0080] A rotary tool according to a fourth aspect of the present disclosure is the rotary tool of any one of the first to third aspects, wherein the second load is constant.

[0081] A rotary tool according to aspect 5 of the present disclosure is the rotary tool according to aspect 4, wherein the second mechanism has a second elastic body extending in a direction along the axis and a second support member supporting the end of the second elastic body opposite the clutch portion, and the second support member is fixed to the housing of the rotary tool.

[0082] A rotary tool according to a sixth aspect of the present disclosure is the rotary tool of the fifth aspect, wherein the second mechanism is separated from the first mechanism.

[0083] A rotary tool according to aspect 7 of the present disclosure is the same as aspect 6, wherein the first mechanism has an adjustment mechanism that accepts an adjustment operation for adjusting the first load, and the second support member is separated from the adjustment mechanism.

[0084] A rotary tool according to an eighth aspect of the present disclosure is the rotary tool of the first or second aspect, wherein the first mechanism and the second mechanism include a first elastic body and a second elastic body, respectively.

[0085] A rotary tool according to a ninth aspect of the present disclosure is the rotary tool of the eighth aspect, wherein the first elastic body is longer than the second elastic body in the direction along the axis.

[0086] A rotary tool according to aspect 10 of the present disclosure is the same as that of aspect 8 or 9, in that the other of the first elastic body and the second elastic body is located inside one of the first elastic body and the second elastic body in a plane perpendicular to the axis.

[0087] A rotary tool according to an eleventh aspect of the present disclosure is the rotary tool of any one of the first to tenth aspects, wherein the first mechanism and the second mechanism are each located closer to the tip end than the clutch portion.

[0088] A rotary tool according to a twelfth aspect of the present disclosure is the rotary tool of any one of the first to eleventh aspects, wherein the first mechanism and the second mechanism are each positioned along a direction parallel to the axis.

[0089] A rotary tool according to aspect 13 of the present disclosure is a rotary tool having a shape extending from the tip to the rear end along an axis, and includes a tip portion located on the tip side and rotatable around the axis, a clutch portion interposed in a transmission path of a rotational driving force for rotating the tip portion and limiting the transmission of the rotational driving force to the tip portion when the rotational driving force exceeds a predetermined magnitude, a first mechanism capable of applying a first load to the clutch portion, and a second mechanism capable of applying a second load to the clutch portion.

[0090] The invention according to the present disclosure has been described above based on the drawings and examples. However, the invention according to the present disclosure is not limited to the above-described embodiments. In other words, the invention according to the present disclosure can be modified in various ways within the scope of the present disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the invention according to the present disclosure. In other words, it should be noted that a person skilled in the art can easily make various modifications or corrections based on the present disclosure. It should also be noted that these modifications or corrections are included in the scope of the present disclosure.

[0091] REFERENCE SIGNS LIST 1 Tip 2 Drive section 3 Grip section 4 Switching section 5 Clutch section 6 First mechanism 7 Second mechanism 8 Adjustment mechanism 9 First elastic body 10 First support member 11 Second elastic body 12 Second support member 13 Housing 101 Rotary tool A Axis S Axis and perpendicular surface

Claims

1. A rotary tool having a shape extending from a tip to a rear end along an axis, comprising: a tip portion located on the tip side and rotatable around the axis; a drive portion that generates a first rotational driving force for rotating the tip portion; a grip portion that receives an input of a second rotational driving force for rotating the tip portion and is located on the rear end side of the tip portion; a switch portion that switches between a first mode in which the first rotational driving force is transmitted from the drive portion to the tip portion and a second mode in which the second rotational driving force is transmitted from the grip portion to the tip portion; a clutch portion that is interposed in a transmission path of the second rotational driving force in the second mode and that limits the transmission of the second rotational driving force to the tip portion when the second rotational driving force exceeds a predetermined magnitude; a first mechanism that can apply a first load to the clutch portion; and a second mechanism that can apply a second load to the clutch portion.

2. The rotary tool according to claim 1, wherein the first mechanism has an adjustment mechanism that accepts an adjustment operation for adjusting the first load.

3. A rotary tool as described in claim 2, wherein the first mechanism has a first elastic body extending in a direction along the axis and a first support member supporting the end of the first elastic body opposite the clutch portion, and the first support member is movable by the adjustment operation.

4. A rotary tool according to any one of claims 1 to 3, wherein the second load is constant.

5. A rotary tool as described in claim 4, wherein the second mechanism has a second elastic body extending in a direction along the axis and a second support member supporting the end of the second elastic body opposite the clutch portion, and the second support member is fixed to the housing of the rotary tool.

6. The rotary tool according to claim 5, wherein the second mechanism is separate from the first mechanism.

7. The rotary tool according to claim 6, wherein the first mechanism has an adjustment mechanism that accepts an adjustment operation for adjusting the first load, and the second support member is separated from the adjustment mechanism.

8. A rotary tool according to claim 1 or 2, wherein the first mechanism and the second mechanism include a first elastic body and a second elastic body, respectively.

9. The rotary tool according to claim 8, wherein the first elastic body is longer than the second elastic body in the direction along the axis.

10. A rotary tool according to claim 8 or 9, wherein, in a plane perpendicular to the axis, one of the first elastic body and the second elastic body is located inside the other of the first elastic body and the second elastic body.

11. A rotary tool according to any one of claims 1 to 10, wherein the first mechanism and the second mechanism are each located closer to the tip than the clutch portion.

12. A rotary tool according to any one of claims 1 to 11, wherein the first mechanism and the second mechanism are each positioned along a direction parallel to the axis.

13. A rotary tool having a shape extending from the tip to the rear end along an axis, comprising: a tip portion located on the tip side and rotatable around the axis; a clutch portion interposed in a transmission path of a rotational driving force for rotating the tip portion and limiting the transmission of the rotational driving force to the tip portion when the rotational driving force exceeds a predetermined magnitude; a first mechanism capable of applying a first load to the clutch portion; and a second mechanism capable of applying a second load to the clutch portion.

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