Patents by Inventor Toshifumi Maehara

Toshifumi Maehara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8869950
    Abstract: Disclosed is a structure such that when pad clips are to be mounted, it is possible to handle return springs and the pad clips as integral articles, thereby facilitating mounting work. Constraining sections are provided at both axial ends of each of the pad clips. Furthermore, the return springs are composed of inner spring elements and outer spring elements. These two types of spring elements are helical torsion springs provided with helical sections. Abutting sections are provided on the spring elements, respectively. The abutting sections are pressed against the inner surfaces of the constraining sections by elastic restoring forces. Moreover, the central axes of the coil sections are substantially oriented in the rotational direction of the rotor.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: October 28, 2014
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventors: Toshifumi Maehara, Daisuke Kobayashi
  • Patent number: 8573370
    Abstract: A cam housing assembly oscillates in association with rotation of an eccentric cam which is attached to a camshaft and is allowed to press a clutch by cam pins of the cam housing assembly. A pair of piston assemblies are provided of which each includes a piston which can slide within a sleeve, a spindle and a nut which screws on to the spindle and are supported in hole portions in a caliper body so as to oscillate therein, whereby a brake pad is pressed against by a plug after the spindle, the nut and the piston are sequentially pressed by pressing a clutch by the cam pins. Since the spindle and the nut are screwed on to each other through a reversible screw, a gap is adjusted automatically as the pad wears.
    Type: Grant
    Filed: July 21, 2010
    Date of Patent: November 5, 2013
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Publication number: 20130025981
    Abstract: Disclosed is a structure such that when pad clips are to be mounted, it is possible to handle return springs and the pad clips as integral articles, thereby facilitating mounting work. Constraining sections are provided at both axial ends of each of the pad clips. Furthermore, the return springs are composed of inner spring elements and outer spring elements. These two types of spring elements are helical torsion springs provided with helical sections. Abutting sections are provided on the spring elements, respectively. The abutting sections are pressed against the inner surfaces of the constraining sections by elastic restoring forces. Moreover, the central axes of the coil sections are substantially oriented in the rotational direction of the rotor.
    Type: Application
    Filed: April 8, 2011
    Publication date: January 31, 2013
    Applicant: AKEBONO BRAKE INDUSTRY CO., LTD
    Inventors: Toshifumi Maehara, Daisuke Kobayashi
  • Publication number: 20120205209
    Abstract: A joining link, a strut, and first and second expansion levers constitute an expansion and contraction device. At the time of the braking, the proximal end portion of both of the expansion levers are mutually pressed from the opposite sides by first and second pressing members constituting a driving device. The reaction due to the braking is offset by the joining link portion, whereby a large force is not applied to the back plate or the like.
    Type: Application
    Filed: November 4, 2010
    Publication date: August 16, 2012
    Inventors: Haruo Tsuzuku, Hiroyasu Ishikawa, Hiroshi Ikegami, Hideki Kakizaki, Toshifumi Maehara
  • Patent number: 8235189
    Abstract: A cylinder body 60 of a wheel cylinder assembly 6 for expanding a pair of brake shoes 3 and 4 by a pair of pistons 31 and 32 brought into contact with the respective brake shoes has a shape of a single straight pipe with both ends which are opened. The cylinder body 60 includes a first cylinder portion 35 for the one 32 of the pistons and a second cylinder portion 34 for the other 31 of the pistons. A valve seat 43 of a control valve 39 is arranged between the cylinder portions 34 and 35.
    Type: Grant
    Filed: June 10, 2008
    Date of Patent: August 7, 2012
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Publication number: 20110017553
    Abstract: A cam housing assembly oscillates in association with rotation of an eccentric cam which is attached to a camshaft and is allowed to press a clutch by cam pins of the cam housing assembly. A pair of piston assemblies are provided of which each includes a piston which can slide within a sleeve, a spindle and a nut which screws on to the spindle and are supported in hole portions in a caliper body so as to oscillate therein, whereby a brake pad is pressed against by a plug after the spindle, the nut and the piston are sequentially pressed by pressing a clutch by the cam pins. Since the spindle and the nut are screwed on to each other through a reversible screw, a gap is adjusted automatically as the pad wears.
    Type: Application
    Filed: July 21, 2010
    Publication date: January 27, 2011
    Applicant: AKEBONO BRAKE INDUSTRY CO., LTD.
    Inventor: Toshifumi MAEHARA
  • Publication number: 20100236878
    Abstract: Among abutment parts (Af, Bf, Cf, Ar) of pad-side engagement parts (11a, 11b) and support-member-side engagement parts (10a, 10a), a portion (Af) which bears a tangential force (Ff) applied to the pad (5a, 6a) during a forward rotation of the rotor on a forward side of the forward rotation of the rotor is positioned inwardly in a radial direction of a rotor with respect to a virtual tangent (k) at a centroid (O) of the pad (5a, 6a) of a virtual circle having a center identical with a center of the rotor and passing through said centroid (O). Among the abutment parts (Af, Bf, Cf, Ar), portions (Bf, Cf) which bear a rotational moment (Mf) applied to the pad (5a, 6a) during the forward rotation of the rotor are positioned at the circumferential both end parts of a support member (2a) and outwardly in the radial direction of the rotor with respect to the virtual tangent (k).
    Type: Application
    Filed: March 10, 2010
    Publication date: September 23, 2010
    Applicant: AKEBONO BRAKE INDUSTRY CO., LTD.
    Inventor: Toshifumi MAEHARA
  • Patent number: 7661515
    Abstract: A solid box-shape structure is constituted by fitting a torque transmitting ring 23 to a guide hole 17 on a guide plate 11 to pivotably hold a lining member 13 and fixing the guide plate 11 to a torque receive plate 3. A braking torque is directly transmitted to the guide plate 11 by the torque transmitting ring 23 by pressing the lining member 13 to a disc rotor by a first link plate 7 and a second link plate 5 arranged on an inner side of the box-shape structure. A solid structure and alleviation of processing accuracy are made to be compatible with each other by constituting transmission of a press force and transmission of a torque by independent members in this way.
    Type: Grant
    Filed: April 20, 2006
    Date of Patent: February 16, 2010
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Patent number: 7490703
    Abstract: A parking-brake operating mechanism is provided with an adjusting spindle, a cam shaft to which a parking lever is connected, and a thrust transmitting assembly disposed between the cam shaft and the adjusting spindle. The thrust transmitting assembly includes a rolling roller which can roll between the cam shaft and the adjusting spindle. Rolling curved surfaces are provided respectively at the cam shaft and the adjusting spindle. The rolling roller is disposed in contact with the rolling curved surfaces.
    Type: Grant
    Filed: December 7, 2005
    Date of Patent: February 17, 2009
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Publication number: 20080302620
    Abstract: A cylinder body 60 of a wheel cylinder assembly 6 for expanding a pair of brake shoes 3 and 4 by a pair of pistons 31 and 32 brought into contact with the respective brake shoes has a shape of a single straight pipe with both ends which are opened. The cylinder body 60 includes a first cylinder portion 35 for the one 32 of the pistons and a second cylinder portion 34 for the other 31 of the pistons. A valve seat 43 of a control valve 39 is arranged between the cylinder portions 34 and 35.
    Type: Application
    Filed: June 10, 2008
    Publication date: December 11, 2008
    Inventor: Toshifumi Maehara
  • Patent number: 7438160
    Abstract: A caliper 2a is disposed between rotation input side and rotation output side engagement portions 8, 9 of a support member 3a so as to restrict the movement of the caliper 2a in a circumferential direction of a rotor 1. A guide pin 26 which supports the caliper 2a is passed through guide holes 22 formed in pressure plates 11 which make up respective pads 10b in such a manner as to be capable of sliding in an axial direction of the rotor 1, whereby the caliper 2a is supported on the respective pads 10b attachably and detachably to the support member 3a while being allowed to move in the axial direction of the rotor 1 relative to the respective pads 10b.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: October 21, 2008
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Patent number: 7178645
    Abstract: A brake apparatus having an automatic clearance adjusting mechanism with an overadjustment preventer constituted such that a piston is constituted by a structure of being divided in a plug piston 16 and a ring piston 14. The plug piston 16 is integrated with an adjusting nut 20, a bearing 21, a bearing support plate 22 and a spring holder 23. An outer side claw portion 23a of the holder is locked by an outer side groove 16 of the plug piston. The plug piston 16 integrated with the respective parts is inserted to fit to the ring piston 14 to thereby prevent the outer side claw portion 23a of the holder from being detached.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: February 20, 2007
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Patent number: 7178643
    Abstract: A cam mechanism 7 provided as a shoe drive mechanism includes a cam supporting plate 21 being loosely and rotatably fitted on an anchor pin 10 for receiving a shoe operating force, a first cam plate 23 rotatably connected to the cam supporting plate 21 at an outer cam supporting position which is a position shifted away from the anchor pin 10 radially outwardly of the drum, a second cam plate 25 rotatably connected to the cam supporting plate 21 at an inner cam supporting position which is away from the anchor pin 10 toward an operating force generator 6, so that a pair of brake shoes 3, 4 are opened outwardly by the separate cam plates 23, 25, respectively.
    Type: Grant
    Filed: June 2, 2004
    Date of Patent: February 20, 2007
    Assignee: Akebono Brake Endustry Co., Ltd.
    Inventors: Toshifumi Maehara, Katsuhiro Miyata, Yukimasa Mitsude, Takayuki Mukasa, Takeshi Noda, Yoshiaki Saitoh
  • Publication number: 20060260885
    Abstract: A support member is provided with an inner side attaching member and a pair of torque receiving members. Each of the torque receiving members is provided with a drawing anchor portion. A cross-section of the drawing anchor portion is formed into an L-shape, an end portion of which is bent to an outer diameter side of the rotor. An engaging protrusion is provided in a pad. The engaging protrusion is opposed to the drawing anchor portion in the circumferential direction.
    Type: Application
    Filed: May 17, 2006
    Publication date: November 23, 2006
    Inventor: Toshifumi Maehara
  • Publication number: 20060237270
    Abstract: A solid box-shape structure is constituted by fitting a torque transmitting ring 23 to a guide hole 17 on a guide plate 11 to pivotably hold a lining member 13 and fixing the guide plate 11 to a torque receive plate 3. A braking torque is directly transmitted to the guide plate 11 by the torque transmitting ring 23 by pressing the lining member 13 to a disc rotor by a first link plate 7 and a second link plate 5 arranged on an inner side of the box-shape structure. A solid structure and alleviation of processing accuracy are made to be compatible with each other by constituting transmission of a press force and transmission of a torque by independent members in this way.
    Type: Application
    Filed: April 20, 2006
    Publication date: October 26, 2006
    Inventor: Toshifumi Maehara
  • Patent number: 7070025
    Abstract: An automatic clearance adjusting device 10 that automatically adjusts the position of brake shoes (3, 4) based on the wear includes an adjuster gear that is rotatably depending on the amount of how much the brake shoes are parted from each other, a cam plate (25) rotated integrally with the adjuster gear (23) to drive the strut (27) that restricts the position of the brake shoes (3, 4), and an adjuster restricting lever (33) that restricts the rotation of the adjuster gear (23) based on the pressing force from the wheel cylinder (6) that parts between the pair of brake shoes (3, 4).
    Type: Grant
    Filed: September 20, 2004
    Date of Patent: July 4, 2006
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Publication number: 20060124407
    Abstract: A parking-brake operating mechanism is provided with an adjusting spindle, a cam shaft to which a parking lever is connected, and a thrust transmitting assembly disposed between the cam shaft and the adjusting spindle. The thrust transmitting assembly includes a rolling roller which can roll between the cam shaft and the adjusting spindle. Rolling curved surfaces are provided respectively at the cam shaft and the adjusting spindle. The rolling roller is disposed in contact with the rolling curved surfaces.
    Type: Application
    Filed: December 7, 2005
    Publication date: June 15, 2006
    Inventor: Toshifumi Maehara
  • Patent number: 7044275
    Abstract: In a drum brake device having a shoe drive cam, the braking force of which is mechanically controlled according to a reaction force acting on an anchor pin by a brake shoe, the cam plate 76 pivotally supported by the anchor pin 10 and the lever plate 30, to which a shoe operating force is given by the operating force generating means 6, are connected to each other being capable of rotating relatively via a pair of cam pins 21, 23 coming into contact with the brake shoes 3, 4, and the transmitting mechanism of the input system composed of the lever plate 30 and the pair of cam pins 21, 23 and the transmitting mechanism of the control system composed of the pair of cam pins 21, 23 and the cam plate 76 are put into a separate state in which a direct power transmission is not conducted between them.
    Type: Grant
    Filed: June 15, 2004
    Date of Patent: May 16, 2006
    Assignee: Akebono Brake Industry Co., Ltd.
    Inventor: Toshifumi Maehara
  • Publication number: 20060054425
    Abstract: A support member 3a for supporting a caliper 2a and pads 10a and 10b includes an inner-side mounting member 17 disposed inwardly of an inner side of a rotor, and a torque receiving member 18 which is separate from the inner-side mounting member 17. The inner-side mounting member 17 and the torque receiving member 18 are connected together by bolts 21 at a position disposed radially outwardly of an outer peripheral edge of the rotor. With this construction, the inner-side mounting member 17 and the torque receiving member 18 can be formed respectively into simple shapes, and besides an operation for machining the torque receiving member 18 can be easily carried out. By doing so, the above problem can be solved.
    Type: Application
    Filed: August 15, 2005
    Publication date: March 16, 2006
    Inventor: Toshifumi Maehara
  • Publication number: 20060054430
    Abstract: A caliper 2a is disposed between rotation input side and rotation output side engagement portions 8, 9 of a support member 3a so as to restrict the movement of the caliper 2a in a circumferential direction of a rotor 1. A guide pin 26 which supports the caliper 2a is passed through guide holes 22 formed in pressure plates 11 which make up respective pads 10b in such a manner as to be capable of sliding in an axial direction of the rotor 1, whereby the caliper 2a is supported on the respective pads 10b attachably and detachably to the support member 3a while being allowed to move in the axial direction of the rotor 1 relative to the respective pads 10b.
    Type: Application
    Filed: September 13, 2005
    Publication date: March 16, 2006
    Inventor: Toshifumi Maehara