JP4798147B2 - Brake structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a brake structure wherein energy loss to be caused by axial movements and inclination of first and second rotors is reduced, and a first rotation shaft and a second rotation shaft are standardized. <P>SOLUTION: In a drive unit 11, a first motor 12 and a second motor 13 are placed so that the axis of the first rotation shaft 14 agrees with that of the second rotation shaft 15. In a brake chamber 21 sectioned between the first motor 12 and the second motor 13, the first and second rotors 36, 41, a stator 43, a pair of brake discs 42a, 42b, and a piston 51 are held. The first rotation shaft 14 and a first cylindrical member 31 are fastened together with a first nut 34 with the first rotation shaft 14 inserted. The second rotation shaft 15 and a second cylindrical member 38 are fastened together with a second nut 39 with the second rotation shaft 15 inserted. In the first cylindrical member 31, a recess 33 is formed on the side of the second-motor to hold at least the first nut 34. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a brake structure, and in particular, is disposed between a first motor and a second motor that are arranged so that the axes of the respective rotating shafts coincide with each other, and the first rotation of the first motor. The present invention relates to a brake structure that brakes the rotation of a first rotor that can rotate integrally with a shaft and a second rotor that can rotate together with a second rotation shaft of a second motor.

  As a brake structure, for example, there is one that is mounted on a drive unit having two motors that are arranged so that the axes of the respective rotating shafts coincide with each other and respectively drive the left and right wheels. And as shown in FIG. 3, this brake structure 100 is installed between the 1st motor 101 and the 2nd motor 102 as two motors. The brake structure 100 includes a first rotor 105 and a second rotor 106 that are spline-fitted to the first rotating shaft 103 of the first motor 101 and the second rotating shaft 104 of the second motor 102, respectively, and the first rotor. 105 and a pair of brake disks 108 and 109 provided so as to sandwich the second rotor 106 therebetween. A stator 107 is provided between the first rotor 105 and the second rotor 106 that can move in the axial direction and cannot rotate. In the brake structure 100, the piston 110 is arranged on the first motor 101 side. When an operating means (not shown) is operated to operate the piston 110, the piston 110 moves to the second motor 102 side and moves to the brake disc. 108 is pressed. Then, the first rotor 105, the second rotor 106, the stator 107, and the pair of brake disks 108 and 109 come into contact with each other to generate a frictional force, thereby braking the rotation of the first rotating shaft 103 and the second rotating shaft 104. .

In addition, as a drive device equipped with a brake structure, each drive shaft has two travel motors that are aligned in the axial direction, and a brake is coupled to each travel motor shaft between the two travel motors. Has been proposed (see, for example, Patent Document 1). As another brake structure, a disc brake is proposed in which a mounting body is spline-fitted to the outer end portion of the rotating shaft, and the mounting body is prevented from coming off by a rotation stopper and a fastener. (For example, refer to Patent Document 2). In the disc brake described in Patent Document 2, the plurality of disc plates and the rotation shaft are integrated by fitting the plurality of disc plates to the attachment body that is spline-fitted with the outer end portion of the rotation shaft. It is configured to be rotatable.
German Patent Application Publication DE102004032167A1 Japanese Utility Model Publication No. 54-107780

However, the conventional brake structure 100 has the following problems (1) to (3).
(1) There is a dimensional tolerance between the bearing that supports the first rotating shaft 103 of the first motor 101 and the housing to which the bearing is attached. Then, as shown in FIG. 4A, a gap A exists between the bearing 112 and the housing 113 on the side opposite to the side where the brake structure 100 is provided due to the accumulation of the dimensional tolerances. Therefore, the first rotation shaft 103 is movable in the axial direction by the gap A. Therefore, when a thrust force acts on the first rotating shaft 103, the first rotating shaft 103 moves in the axial direction by the gap A, and accordingly, the first rotor 105 and the brake disk 108 are easily brought into contact with each other. . Such a gap between the bearing and the housing also exists in the bearing that supports the second rotating shaft 104. Therefore, the conventional brake structure 100 has a problem that the first rotor 105 and the second rotor 106 may come into contact with the brake discs 108 and 109 during non-braking, resulting in energy loss.

  (2) The first rotor 105 is coupled to the first rotating shaft 103 so as to be movable in the axial direction. As shown in FIG. 4B, an outer spline 114 provided on the first rotating shaft 103 and There is a gap S between the inner spline 115 provided in the first rotor 105. Therefore, the first rotor 105 may be tilted from the state indicated by the two-dot chain line in FIG. 4C to the state indicated by the solid line in FIG. As shown in FIG. 4C, the inclination angle θ1 with respect to the axial direction when the first rotor 105 is inclined is equal to the inclination angle θ2 with respect to the direction orthogonal to the axial direction, and the dotted line in FIG. The triangle V1 illustrated with diagonal lines is similar to the triangle V2 illustrated with solid diagonal lines in FIG. 4C. Therefore, the following relational expression (a) is established between the inclination of the first rotor 105 and the displacement amount B of the first rotor 105 in the axial direction.

なお、δ隙間、ｄは第１ロータの厚さ、Ｒは第１ロータの外半径、ｒはスプライン半径である。関係式（ａ）より、第１ロータ１０５をスプライン嵌合する第１回転軸１０３のスプライン半径ｒが小さいほど第１ロータ１０５の軸線方向への変位量Ｂは大きくなる。そして、第１ロータ１０５が傾いて軸線方向に変位した分、第１ロータ１０５はステータ１０７又はブレーキディスク１０８と接触、若しくは第１ロータ１０５とステータ１０７又はブレーキディスク１０８との間のクリアランスが小さくなる。したがって、従来のブレーキ構造１００においては、第１ロータ１０５が回転する際に抵抗を受けてエネルギー損失が増大するという問題がある。なお、第２ロータ１０６の内スプラインと第２回転軸１０４の外スプラインとにおいても隙間は存在するため、第２ロータ１０６とブレーキディスク１０９との間においても、同様にエネルギー損失が生じるという問題がある。

Δ gap, d is the thickness of the first rotor, R is the outer radius of the first rotor, and r is the spline radius. From the relational expression (a), the amount of displacement B in the axial direction of the first rotor 105 increases as the spline radius r of the first rotating shaft 103 for spline-fitting the first rotor 105 decreases. The first rotor 105 is in contact with the stator 107 or the brake disk 108, or the clearance between the first rotor 105 and the stator 107 or the brake disk 108 is reduced by the amount of the first rotor 105 tilted and displaced in the axial direction. . Therefore, the conventional brake structure 100 has a problem in that energy loss increases due to resistance when the first rotor 105 rotates. In addition, since there is a gap between the inner spline of the second rotor 106 and the outer spline of the second rotating shaft 104, there is a problem that energy loss similarly occurs between the second rotor 106 and the brake disk 109. is there.

  (3) In the conventional brake structure 100, since the piston 110 is disposed on the first motor 101 side, the first rotating shaft 103 is made longer than the second rotating shaft 104, and the first rotor 105 is spline-fitted. enable. For this reason, separate ones must be prepared for the first rotating shaft 103 and the second rotating shaft 104, which is economically disadvantageous. If the first and second rotating shafts 103 and 104 have the same length, the second rotating shaft 104 is unnecessarily long, so the width of the entire drive unit is increased. There is also a problem that it ends up.

  In Patent Document 1, a brake structure installed between two motors is disclosed, but there is no description that suggests countermeasures for problems (1) to (3). Further, Patent Document 2 only discloses that the disk plate is attached to the outer end portion of the rotating shaft via an attachment body, and the disk brake described in Patent Document 2 is between two motors. There is no description about the points to be arranged. Therefore, in patent document 2, there is no description which suggests regarding the countermeasure of a problem like (3).

  The present invention has been made in view of the above-mentioned problems, and its object is to reduce energy loss due to movement and inclination of the first rotor and the second rotor in the axial direction, and An object of the present invention is to provide a brake structure that can share a single rotating shaft and a second rotating shaft.

  In order to achieve the above object, the invention according to claim 1 is arranged between a first motor and a second motor arranged so that axes of respective rotary shafts coincide with each other, and In the brake structure for braking the rotation of the first rotor that can rotate integrally with the first rotating shaft of one motor and the second rotor that can rotate integrally with the second rotating shaft of the second motor, the first rotating shaft and the first A bearing that rotatably supports the two rotation shafts, at least a pair of brake disks that are disposed so as to sandwich the first rotor and the second rotor, and that are movable in the axial direction and are not rotatable; A stator provided between the rotor and the second rotor, which is movable in the axial direction and is not rotatable, and is provided closer to the first motor than the pair of brake disks. The first fastening is performed with the operating body capable of pressing the brake disc on the first motor side of the pair of brake discs toward the first rotor and the first rotating shaft being inserted and in contact with the bearing. A first cylindrical member fastened to the first rotating shaft by a member and the first rotor being spline-fitted, and a second fastening member in a state in which the second rotating shaft is inserted and in contact with the bearing A second cylindrical member fastened to the second rotating shaft by which the second rotor is spline-fitted, and the first cylindrical member opens to the second motor side and at least the first The gist is that a recess for accommodating one fastening member is formed.

  In this invention, when the operating body operates, the brake disk on the first motor side presses the first rotor, moves the first rotor to the second motor side, and presses it against the stator. Then, the stator moves to the second motor side to press the second rotor, and moves the second rotor to the second motor side to press it against the brake disk on the second motor side. Accordingly, the first rotor and the second rotor come into contact with the pair of brake discs and the stator, and friction is generated between the first rotor and the second rotor and the pair of brake discs and the stator. The rotation of the two rotors is braked.

  Moreover, since the 1st cylinder member and the 2nd cylinder member are each contact | abutted to the bearing by which the movement was controlled, the movement to the axial direction of a 1st rotating shaft and a 2nd rotating shaft is controlled. Therefore, since the first rotor and the second rotor are restrained from moving in the axial direction during non-braking, energy loss caused by the first rotor and the second rotor coming into contact with the brake disk during non-braking can be reduced.

  In addition, even if the diameters of the first rotating shaft and the second rotating shaft are the same as the conventional ones, the first rotor and the second rotor are spline-fitted to the first cylindrical member and the second cylindrical member, respectively. The difference between the outer radii of the first rotor and the second rotor and the spline radii of the first cylindrical member and the second cylindrical member is smaller than in the prior art. Therefore, even if the first rotor and the second rotor are inclined, the displacement amount in the axial direction of the first rotor and the second rotor is small, and the first rotor and the second rotor are caused by receiving extra resistance from the brake disc. Energy loss can be reduced.

  Further, in the recess, the first cylindrical member is fastened to the first rotating shaft by the first fastening member, and the first rotor is spline-fitted with the first cylindrical member regardless of the length of the first rotating shaft. The first rotor and the first rotation shaft can rotate integrally. Therefore, since the thing of the same length as a 2nd rotating shaft can be used as a 1st rotating shaft, a 1st rotating shaft and a 2nd rotating shaft can be made common without trouble.

  According to a second aspect of the present invention, in the first aspect of the present invention, the concave portion is formed so as to be able to accommodate the first fastening member and the second fastening member, and the second fastening is provided in the concave portion. The gist is that the member is also accommodated.

  In this invention, the second fastening member is accommodated in the recess. Therefore, since it is not necessary to leave an interval for disposing the second fastening member between the first cylinder member and the second cylinder member, the length of the drive device on which the brake structure is mounted remains the same as before, The first rotating shaft and the second rotating shaft can be shared.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the diameter of the first motor side end of the first cylinder member and the second motor side end of the second cylinder member. The diameter is formed to be the same as the outer diameter of the inner ring of the bearing and is used as a wet brake.

  In this invention, even if the first cylinder member and the second cylinder member are fastened to the first rotating shaft and the second rotating shaft in a state where they are in contact with the bearings, the oil remains in the sliding portion between the inner ring of the bearing and the rolling element. Can flow smoothly.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to reduce the energy loss resulting from the movement and inclination to the axial direction of a 1st rotor and a 2nd rotor, it can make a 1st rotating shaft and a 2nd rotating shaft common. it can.

Hereinafter, an embodiment in which the present invention is embodied in a brake structure for a battery-type forklift drive unit will be described with reference to the drawings.
As shown in FIG. 1, a drive unit 11 as a driving device for a battery-type forklift has a first motor 12 for driving the left wheel and a second motor 13 for driving the right wheel in series, that is, the first motor 12. It arrange | positions so that the axis line of the 1st rotating shaft 14 and the 2nd rotating shaft 15 of the 2nd motor 13 may correspond. The first rotating shaft 14 of the first motor 12 and the second rotating shaft 15 of the second motor 13 are the same. In the drive unit 11, a first housing 16 and a second housing 17 are joined by bolts 18. The first housing 16 and the second housing 17 are each provided with a first partition wall 19 and a second partition wall 20 extending so as to protrude inward from the inner periphery thereof, and a brake chamber 21 capable of storing oil is provided as a first motor 12. And the second motor 13.

  In the brake chamber 21, a protruding end 22 of the first rotating shaft 14 extends from the first motor side, and a protruding end 23 of the second rotating shaft 15 extends from the second motor side. In the present embodiment, the left side of FIG. 1 is described as the first motor side, and the right side of FIG. 1 is described as the second motor side. The first rotating shaft 14 is rotatably supported by a pair of first bearings 24 attached to the first partition wall 19. The second rotating shaft 15 is rotatably supported by a pair of second bearings 25 attached to the second partition wall 20. In FIG. 1, only the first bearing 24 and the second bearing 25 on the side close to the brake chamber 21 are illustrated. A lid member 27 is fastened to the wall surface of the first partition wall 19 opposite to the side wall surface of the brake chamber 21 by a bolt 26, and the first bearing 24 is clamped and fixed by the first partition wall 19 and the lid member 27. Has been. A lid member 29 is fastened to the wall surface of the second partition wall 20 opposite to the side wall surface of the brake chamber 21 by bolts 28, and the second bearing 25 is sandwiched and fixed by the second partition wall 20 and the lid member 29. ing.

  An outer spline 30 is formed on the protruding end portion 22 of the first rotating shaft 14, and a male screw portion (not shown) is formed on the tip side of the outer spline 30. The protruding end portion 22 is inserted into the first cylinder member 31 and is spline-fitted with the first cylinder member 31.

  The first cylindrical member 31 is formed with a tapered portion 32 at the intermediate portion, and the diameter S1 of the end portion 31a on the first motor 12 side is set to be the same as the diameter P1 of the inner ring of the first bearing 24. ing. The first cylindrical member 31 is formed with a recess 33 that opens to the second motor 13 side, and a male screw portion (not shown) of the protruding end 22 protrudes into the recess 33. And the 1st nut 34 as a 1st fastening member is screwed by the external thread part of the protrusion end part 22. As shown in FIG. The first nut 34 fastens the first rotating shaft 14 and the first cylinder member 31 with the first cylinder member 31 pressed against the first bearing 24. An outer spline 35 is formed on the outer peripheral portion of the first cylindrical member 31 and is engaged with the annular first rotor 36 by spline. The spline radius r1 of the first cylindrical member 31 is formed to be larger than the diameter S1 of the end portion on the first motor 12 side.

  The first rotor 36 is configured to be able to rotate integrally with the first cylindrical member 31 and to be slidable in the axial direction of the first rotating shaft 14. Further, the spline radius r1 of the first cylindrical member 31 to which the first rotor 36 is spline-fitted is larger than the radius of the first rotating shaft 14. Therefore, the difference between the outer radius R1 of the first rotor 36 and the spline radius r1 of the first cylindrical member 31 (the first rotor 36 compared to when the first rotor 36 is spline-fitted to the first rotating shaft 14). The ring width) is smaller.

  On the other hand, an outer spline 37 is formed on the protruding end portion 23 of the second rotating shaft 15, and a male screw portion (not shown) is formed on the tip side of the outer spline 37. The protruding end portion 23 is inserted into the second cylindrical member 38 so that the male screw portion protrudes and is spline-fitted with the second cylindrical member 38.

  In the second cylindrical member 38, the diameter S2 of the end 38a on the second motor 13 side is set to be the same as the diameter P2 of the inner ring of the second bearing 25. The second cylindrical member 38 is pressed against the second bearing 25 and fastened to the second rotating shaft 15 by a second nut 39 as a second fastening member screwed to the male screw portion of the protruding end portion 23. And the recessed part 33 of the 1st cylinder member 31 is comprised so that both the 1st nut 34 and the 2nd nut 39 can be accommodated while opening so that the 2nd cylinder member 38 may be opposed. For this reason, the second nut 39 and the projecting end portion 23 extending toward the first motor 12 relative to the second nut 39 are accommodated in the recess 33 of the first cylindrical member 31. In addition, an outer spline 40 is formed on the outer peripheral portion of the second cylindrical member 38 and is spline-fitted with an annular second rotor 41. The spline radius r2 of the second cylindrical member 38 is formed to be larger than the diameter S2 of the end portion on the second motor 13 side.

  The second rotor 41 is configured to be able to rotate integrally with the second rotating shaft 15 and to be slidable in the axial direction of the second rotating shaft 15. Further, the spline radius r <b> 2 of the second cylindrical member 38 in which the second rotor 41 is spline-fitted is larger than the radius of the second rotating shaft 15. Therefore, the difference between the outer radius R2 of the second rotor 41 and the spline radius r2 of the second cylindrical member 38 (the second rotor 41) compared to when the second rotor 41 is spline-fitted to the second rotating shaft 15. The ring width) is smaller.

  The brake chamber 21 is provided with a pair of annular brake disks 42 a and 42 b so as to sandwich the first rotor 36 and the second rotor 41, and between the first rotor 36 and the second rotor 41. An annular stator 43 is provided between them.

  A friction material (not shown) is attached to the pair of brake disks 42a and 42b on the surfaces facing the first rotor 36 and the second rotor 41, respectively, and a clearance (not shown) is provided between the first rotor 36 and the second rotor 41. Is set. The brake discs 42a and 42b are formed with a plurality of protrusions 44 and 45 on their outer peripheral portions so that the brake discs 42a and 42b cannot rotate and can slide in the axial direction. The protrusions 44 and 45 are fitted into a groove (not shown) formed in the first housing 16 or the second housing 17.

  A friction material (not shown) is attached to the stator 43 on a surface facing the first rotor 36 and a surface facing the second rotor 41. A plurality of protrusions 46 are formed on the outer periphery of the stator 43 so that the stator 43 cannot rotate and can slide in the axial direction. The protrusion 46 is fitted with a groove (not shown) formed inside the first housing 16, and a hole 48 through which the spring pin 47 can be inserted is formed.

  On both sides of the spring pin 47, first and second return springs 49 and 50 are provided between the stator 43 and the brake disks 42a and 42b and between the stator 43 and the brake disks 42a and 42b. The spring pin 47 supports the first and second return springs 49 and 50 on both sides thereof. The first and second return springs 49 and 50 have their respective brake discs 42a and 42b so as to ensure a clearance between the brake discs 42a and 42b and the first rotor 36 and the second rotor 41 during non-braking. Is urged away from the first rotor 36 and the second rotor 41.

  A piston 51 is provided between the brake disk 42 a close to the first motor 12 and the first partition wall 19 as an operating body capable of pressing the brake disk 42 a toward the first rotor 36. The piston 51 has a fixed ring 52 fixed to the first partition wall 19, a rotatable cam ring 53 that is movable in the axial direction, and a steel that is sandwiched between the fixed ring 52 and the cam ring 53 so as to be able to roll. And a sphere 54. In addition, the structure of the fixing ring 52, the cam ring 53, and the steel ball 54 is comprised similarly to the fixing ring, cam ring, and steel ball which are disclosed by Unexamined-Japanese-Patent No. 2000-289588. In the fixed ring 52 and the cam ring 53, a fixed cam groove 55 and a movable cam groove 56 are formed on the end surfaces facing each other. The cam ring 53 is configured to rotate when an operation mechanism (not shown) is operated, and is configured to move to the brake disk 42a side and press the brake disk 42a when rotated.

  Even if the length of the first rotating shaft 14 does not reach the first rotor 36, the first rotating shaft 14 is coupled to the first rotor 36 via the first cylindrical member 31. ing. Therefore, the first rotor 36 is configured to rotate integrally with the first rotating shaft 14 even if the first rotating shaft 14 and the second rotating shaft 15 having the same length are used. Further, the output side end portions (not shown) of the first and second rotary shafts 14 and 15 existing on the side opposite to the projecting end portions 22 and 23 of the first rotary shaft 14 and the second rotary shaft 15 are helical gears. It connects so that it may link with the gear mechanism which is not shown in figure. The gear mechanism is configured to transmit the rotational force to the left and right wheels of the forklift when the first rotating shaft 14 and the second rotating shaft 15 rotate.

Next, the operation of the drive unit 11 configured as described above will be described.
The drive unit 11 rotates the first rotating shaft 14 of the first motor 12 and the second rotating shaft 15 of the second motor 13, and transmits the rotational force to the left and right wheels of a battery-type forklift (not shown) via a gear mechanism. A forklift is driven. When the forklift is accelerated or decelerated during traveling of the forklift, a thrust force is applied to the first rotating shaft 14 and the second rotating shaft 15 from a gear mechanism having a helical gear. At this time, even if the first rotating shaft 14 moves to the left in FIG. 1 along the axial direction, the movement of the first rotating shaft 14 is restricted because the first cylindrical member 31 is in contact with the first bearing 24. Is done. Similarly, even if the second rotary shaft 15 tries to move to the right side in FIG. 1 along the axial direction, the second cylindrical member 38 is in contact with the second bearing 25, so that the second rotary shaft 15 moves. Is regulated. Therefore, even when a thrust force is applied to the first rotating shaft 14 and the second rotating shaft 15 during acceleration / deceleration of the forklift, the first rotor 36 and the second rotor 41 are restricted from moving in the axial direction. As a result, energy loss caused by the first rotor 36 and the second rotor 41 contacting the brake disks 42a and 42b, respectively, during non-braking can be reduced.

  Further, since there are spline gaps between the first rotor 36 and the first cylinder member 31 and between the second rotor 41 and the second cylinder member 38, for example, the first rotor 36 and When the vibration is applied to the second rotor 41, the first rotor 36 and the second rotor 41 may be inclined. However, as shown in FIG. 1, the first rotor 36 is spline-fitted with the first cylindrical member 31, and the spline radius r <b> 1 is larger than the radius of the first rotating shaft 14, so the outer radius R <b> 1 of the first rotor 36. And the spline radius r1 of the first cylindrical member 31 is small. Therefore, even when the first rotor 36 is inclined, the displacement amount of the first rotor 36 in the axial direction is small. Therefore, a clearance can be secured between the first rotor 36, the stator 43, and the brake disk 42a, and energy loss caused by the first rotor 36 tilting and receiving extra resistance from the stator 43 or the brake disk 42a is reduced. be able to. Also in the second rotor 41, the difference between the outer radius R2 of the second rotor 41 and the spline radius r2 of the second cylindrical member 38 is smaller than that of the conventional brake structure. Energy loss caused by receiving extra resistance from 42b can be reduced.

  Further, when an operating mechanism (not shown) of the drive unit 11 is operated and the cam ring 53 rotates, the cam ring 53 moves to the second motor side and presses the brake disk 42a on the first motor side. Then, the brake disc 42 a presses the first rotor 36 to move it to the second motor side and presses it against the stator 43. The stator 43 is pressed by the first rotor 36 and moves to the second motor side to press the second rotor 41, and the second rotor 41 moves to the second motor side and the brake disc on the second motor side. 42b. Accordingly, the first rotor 36 contacts the brake disk 42 a and the stator 43, and the second rotor 41 contacts the brake disk 42 b and the stator 43. Further, friction is generated between the first rotor 36 and the brake disk 42 a and the stator 43 and between the second rotor 41 and the brake disk 42 b and the stator 43. As a result, the first rotor 36 and the second rotor 41 are braked, and the forklift stops.

In this embodiment, the following effects can be obtained.
(1) The first cylindrical member 31 is fastened to the first rotating shaft 14 in a state of being in contact with the first bearing 24. The second cylinder member 38 is fastened to the second rotating shaft 15 in contact with the second bearing 25. Therefore, the first rotor 36 and the second rotor 41 are restricted from moving in the axial direction during non-braking, and the first rotor 36 and the second rotor 41 come into contact with the brake disks 42a and 42b, respectively, during non-braking. The resulting energy loss can be reduced.

  (2) The first rotor 36 is spline-fitted with the first cylindrical member 31 in which the first rotating shaft 14 is inserted. The second rotor 41 is spline-fitted with the second cylindrical member 38 in which the second rotating shaft 15 is inserted. Therefore, it is possible to reduce energy loss caused by the first rotor 36 and the second rotor 41 receiving useless resistance from the stator 43 or the brake disks 42a and 42b.

  (3) The first rotating shaft 14 is inserted into the first cylindrical member 31 and fastened to the first cylindrical member 31 with the protruding end 22 protruding into the recess 33. The first rotor 36 is spline-fitted with the first cylindrical member 31 at a position closer to the second motor 13 than the tip of the protruding end 22. Therefore, even if the first rotating shaft 14 and the second rotating shaft 15 are made common, the first rotor 36 can be configured to rotate integrally with the first rotating shaft 14.

  (4) The recess 33 accommodates both the first nut 34 and the second nut 39. Therefore, since it is not necessary to provide a space for disposing the second nut 39 between the first cylinder member 31 and the second cylinder member 38, the axial direction dimension of the drive unit 11 remains the same as the conventional one, and the first rotation. The shaft 14 and the second rotating shaft 15 can be shared.

  (5) Oil is stored in the brake chamber 21 that houses the first rotor 36, the second rotor 41, the pair of brake disks 42 a and 42 b, and the stator 43. The diameter S1 of the end 31a of the first cylindrical member 31 on the first motor 12 side is set to be the same as the diameter P1 of the inner ring of the first bearing 24. The diameter S2 of the end 38a of the second cylinder member 38 on the second motor 13 side is set to be the same as the diameter P2 of the inner ring of the second bearing 25. Accordingly, the oil can smoothly flow into the sliding portion between the inner ring and the rolling element in the first bearing 24 and the second bearing 25, and the durability of the first bearing 24 and the second bearing 25 is reduced. Can be suppressed.

  (6) Here, when the first cylinder member 31 and the second cylinder member 38 are fastened to the first rotating shaft 14 and the second rotating shaft 15 respectively by bolts, a screw hole into which the bolt can be screwed is formed on the rotating shaft. There is a need to. However, since the first nut 34 is used as the first fastening member and the second nut 39 is used as the second fastening member, there is no need to form screw holes in the first rotating shaft 14 and the second rotating shaft 15. It can suppress that the intensity | strength of the 1st rotating shaft 14 and the 2nd rotating shaft 15 falls.

  (7) The spline radius r1 of the first cylindrical member 31 is formed to be larger than the diameter S1 of the end portion 31a on the first motor 12 side. The spline radius r2 of the second cylinder member 38 is formed to be larger than the diameter S2 of the end 31a on the second motor 13 side. Accordingly, the first cylindrical member 31 is compared with the case where the first cylindrical member and the second cylindrical member having the same diameter as the inner rings of the first bearing 24 and the second bearing 25 and having a constant diameter are used. In addition, the spline radii r1 and r2 of the second cylindrical member 38 can be increased. As a result, the amount of displacement in the axial direction of the first rotor 36 and the second rotor 41 when the first rotor 36 and the second rotor 41 are tilted can be reduced.

The embodiment is not limited to the above, and may be embodied as follows, for example.
○ The shape of the first cylinder member may be changed, or the shape of the second cylinder member may be changed. For example, the diameter of the first motor 12 side end of the first cylinder member 31 may be larger than the diameter of the inner ring of the first bearing 24, or the diameter of the end of the second cylinder member 38 on the second motor 13 side. May be larger than the diameter of the inner ring of the second bearing 25. However, in this case, it is necessary that the flow path of the oil flowing between the inner ring and the rolling element in the first bearing 24 and the second bearing 25 is not completely blocked. In addition, if the target durability can be sufficiently ensured even if the ring width of the first rotor 36 is reduced without interfering with the piston 51, the end portion on the second motor 13 side of the first cylindrical member 31 is provided. The diameter of 38a may be enlarged. If the target durability can be sufficiently ensured even if the ring width of the second rotor 41 is reduced, the diameter of the end portion of the second cylinder member 38 on the first motor 12 side may be increased. Further, the first cylinder member may be formed so that the outer diameter of the first cylinder member is constant, or the second cylinder member may be formed so that the outer diameter of the second cylinder member is constant. .

  (Circle) you may arrange | position a 2nd fastening member outside the recessed part of a 1st cylinder member. In this case, for example, the thickness of the stator 43 is increased, and an interval in which the second fastening member can be disposed between the first rotor 36 and the second rotor 41 is ensured.

  (Circle) you may change the member used as a 1st fastening member and a 2nd fastening member. For example, a first bolt is used instead of the first nut 34, a screw hole into which the first bolt can be screwed is formed in the first rotating shaft 14, and the first cylinder is screwed into the screw hole. The member 31 may be fastened to the first rotating shaft 14 while being pressed against the first bearing 24. Further, a second bolt is used in place of the second nut 39, a screw hole into which the second bolt can be screwed is formed in the second rotary shaft 15, and the second bolt is screwed into the screw hole to thereby form the second cylinder. The member 38 may be fastened to the second rotating shaft 15 while being pressed against the second bearing 25. However, in this case, the depth and diameter of the screw holes formed in the first rotating shaft 14 and the second rotating shaft 15 are set so that the first rotating shaft 14 and the second rotating shaft 15 can sufficiently secure the target strength. Need to design.

  The first rotor and the second rotor may be divided into a plurality of parts in the axial direction. In this case, an annular intermediate plate in which a friction material is attached between the plurality of divided first rotors is interposed, and a circle in which the friction material is attached between the plurality of divided second rotors. An intermediate intermediate plate is interposed. When the cam ring 53 moves to the second motor side and presses the brake disk 42a, the plurality of first rotors come into contact with the brake disk 42a, the stator 43, and the intermediate plate, and the rotation of the first rotor is braked. At the same time, the plurality of second rotors come into contact with the brake disc 42b, the stator 43 and the intermediate plate, and the rotation of the second rotor is braked.

  O You may change the structure of the action body which can press a brake disc toward a 1st rotor. For example, as shown in FIG. 2, a piston 57 is provided between the brake disks 42 a and 42 b and the first partition wall 19. An annular pressure receiving portion 58 is provided on the outer peripheral portion of the piston 57, and a protrusion 59 is provided at the first motor side corner of the brake chamber 21 facing the pressure receiving portion 58. Further, a pressure action chamber 60 is defined between the pressure receiving portion 58 and the protrusion 59. In this configuration, oil is supplied to the pressure working chamber 60 at the time of braking and the pressure inside the pressure working chamber 60 is made higher than that of the brake chamber 21 to move the piston 57 to the first motor 12 side. The piston 57 is separated from the brake disks 42a and 42b by lowering the pressure in the chamber 60 and setting the pressure acting chamber 60 to the same pressure as the brake chamber 21. Further, air may be used instead of oil as a fluid to be supplied for adjusting the pressure in the pressure working chamber 60.

  ○ As long as the first rotating shaft can be rotatably supported, the type of the first bearing is not particularly limited. Similarly, the type of the second bearing is not particularly limited as long as the second rotating shaft can be rotatably supported. For example, a roller bearing may be used as the first bearing, and a roller bearing may be used as the second bearing.

  The present invention may be used as a brake structure of a device other than a battery-type forklift drive unit as long as the first motor and the second motor arranged in series are used as a drive source. The present invention may be used, for example, as a brake structure for a drive device that drives traveling of an industrial vehicle other than a forklift.

  If the present invention is used as a brake structure for a device that requires a relatively small braking force, the present invention may be a dry brake.

The partial fracture | rupture schematic cross section of the brake structure of this embodiment. The typical fragmentary sectional view of the brake structure in another embodiment. The partially broken schematic cross section which shows the conventional brake structure. (A) is a partial schematic cross-sectional view showing a support state of a first rotating shaft of a first motor by a bearing in a drive unit having a conventional brake structure, and (b) is a diagram showing the relationship between the first rotating shaft and the first rotor. The schematic diagram which shows the state fitted by the spline, (c) is a schematic diagram which shows the state which the 1st rotor inclined.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 12 ... 1st motor, 13 ... 2nd motor, 14 ... 1st rotating shaft, 15 ... 2nd rotating shaft, 24 ... 1st bearing, 25 ... 2nd bearing, 31 ... 1st cylinder member, 34 ... 1st fastening First nut as member, 36 ... first rotor, 38 ... second cylindrical member, 39 ... second nut as second fastening member, 41 ... second rotor, 42a ... brake disc, 42b ... brake disc, 43 ... Stator, 51... Piston as an operating body.

Claims (3)

A first rotor that is disposed between a first motor and a second motor that are arranged such that the axes of the respective rotating shafts coincide with each other, and that can rotate integrally with a first rotating shaft of the first motor; In the brake structure for braking the rotation of the second rotor that can rotate integrally with the second rotating shaft of the second motor,
A bearing that rotatably supports the first rotating shaft and the second rotating shaft;
At least a pair of brake discs arranged so as to sandwich the first rotor and the second rotor, movable in the axial direction and not rotatable;
A stator provided between the first rotor and the second rotor, movable in the axial direction and non-rotatable;
An actuator that is provided closer to the first motor than the pair of brake discs, and capable of pressing the brake disc on the first motor side of the pair of brake discs toward the first rotor;
A first tubular member that is fastened to the first rotating shaft by a first fastening member in a state in which the first rotating shaft is inserted and in contact with the bearing; and the first rotor is spline-fitted,
A second cylindrical member that is fastened to the second rotary shaft by a second fastening member in a state in which the second rotary shaft is inserted and in contact with the bearing, and the second rotor is spline-fitted. Prepared,
The brake structure according to claim 1, wherein the first cylindrical member is formed with a recess that opens to the second motor side and accommodates at least the first fastening member. The recess is formed so as to accommodate the first fastening member and the second fastening member,
The brake structure according to claim 1, wherein the second fastening member is also accommodated in the recess. The diameter of the first motor side end of the first cylinder member and the diameter of the second motor side end of the second cylinder member are respectively formed to be the same as the outer diameter of the inner ring of the bearing,
The brake structure according to claim 1 or 2, which is used as a wet brake.

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