Howa Machinery, Ltd.

Koganei Corporation

Mitsuo Noda

Tsuyoshi Yonezawa

Akiyoshi Horikawa

Hiroshi Yoshida

Naoki Minowa

Tadanori Sugimoto

Kanji Miyata

Tuyoshi Yonezawa

Yuichi Ishitani

Naoki c/o Koganei Corporation Minova

Akiyoshi Koganei Corporation Horikawa

Naoki Koganei Corporation Minowa

Hiroshi Koganei Corporation Yoshida

Hiroshi c/o Koganei Corporation Yoshida

Akiyoshi c/o Koganei Corporation Horikawa

Naoki c/o Koganei Corporation Minowa

A pair of cylinder holesare formed in a cylinder tubein the axial direction, a slitis formed between these cylinder holes, and an iron plateis inserted in the slit covering the whole range of the movement of the pistonsin the cylinder holes. Spacersmade of a synthetic resin are interposed on both sides of the iron plateto reliably hold the iron platein the slit. The iron platedisposed between the cylinder holes works to decrease the repulsive force acting between the inner magnetsof the pistons and produce an attracting force between the iron plateand the inner magnets, and a contact surface pressure between the wear ringsof the pistonsand the wall surfaces of the cylinder holescan be adjusted to a suitable value.

Magnet type rodless cylinder

A pair of independent cylinder holesare formed in a cylinder tubeof a flat outer shape. When a pressurized fluid is alternately supplied into the cylinder tubethrough a portformed in an end cap, the internal pressure for operating the cylinders acts uniformly on the cylinder tubegreatly decreasing stress and deflection of the cylinder tube

Repulsive magnetic forces in the axial direction of cylinder tubes act between the rowsof inner magnets of pistonsaccommodated in two cylinder tubes, and the inner magnetsof the pistonscome to a halt being slightly deviated relative to the outer magnetsin the axial direction of the tube. Due to this deviation, a magnetic holding force Fc is produced between the inner and outer magnets. Since the magnetic holding force Fc is produced in a static state, a smooth movement can be attained from a static state suppressing the occurrence of a stick slip phenomenon at the start of movement as compared to the prior art, which does not produce the magnetic holding force in a static state.

A magnet type rodless cylinder provided with a slide magnetically coupled with a piston arranged in a cylinder tube and a slide able to move outside of the cylinder tube. The slide has a connection mount detachably attached to it. When attaching the connection mount, the position where the connection mount and an end cap strike/contact becomes the striking/contacting position of the piston. When using a rodless cylinder without a connection mount, the distance between the slide and an end cap when the piston is positioned at the striking/contacting position becomes longer than the striking/contacting distance due to the removal of the connection mount. Therefore, external dampers able to strike/contact the slide are detachably attached to the end caps at the slide sides. Due to this, regardless of the use or nonuse of a connection mount, the piston and slide can always stop at the striking/contacting position.

A magnet type rodless cylinder comprised of cylinder tube of a double tube structure provided with an outside tube of an elliptical flattened outside circumferential shape and two inside tubes inserted into the outside tube. When pressurized air is supplied alternately to the inside tubes from a port provided at an end cap, two pistons move reciprocatingly inside the inside tubes. Due to this reciprocating motion, this reciprocating motion causes reciprocating motion of a slide magnetically coupled with the two pistons at the outside of the outside tube. The inside pressure caused by the pressurized air acts exclusively on the inside tubes and does not directly act on the outside tube of the flattened outside circumferential shape, so the thickness of the outside tube can be reduced and, even if the cylinder tube is made a double tube structure, the total thickness will not become greater than in the past. For this reason, it is possible to provide a practical flattened type of magnetic cylinder with a small height without greatly increasing the magnetic coercive force.

Rodless cylinder

A clamping cylinder actuator has a front end cover ( ). A back surface ( ) of the front end cover ( ) has a joining surface ( ) joined to a fixed member ( ). A thin, flat gasket ( ) formed from elastic rubber materials and such is interposed between the front end cover ( ) and a front end surface of a cylinder ( ) facing the front end cover ( ). The gasket ( ) is fitted on a boss ( ) formed on the front end cover ( ) and extends over the entire back surface of the front end cover ( ) having a sealing surface ( ) surrounded by the joining surface ( ). When the front end cover ( ) is fastened to the fixed member ( ) with bolts ( ), the gasket is held between the front end cover ( ) and the fixed member ( ). The gasket ( ) prevents the loosening of the bolts ( ).

Clamping cylinder actuator

A rotary cylinder actuator has a piston rod placed in a cylinder, provided in its surface with a guide groove and capable of being moved axially between a position corresponding to a clamping angular position and a position corresponding to an unclamping angular position. A guide member is attached to the cylinder to engage in the guide groove. The piston rod turns from a first angular end position toward a second angular end position for normal turning and turns from the second angular end position toward the first angular end position for reverse turning. The opposite guide surfaces of the guide groove serve as a first guide surface for normal turning and a second guide surface for reverse turning, respectively, so that the guide member moves relative to the piston along different paths in the guide groove while the piston rod turns for normal turning and reverse turning, respectively. The first guide surface and the second guide surface are formed so that the guide member moves relative to the piston rod along a path having a shape of a section of a sine curve or a cosine curve in a final stage of movement of the piston rod, and the guide member moves relative to the piston rod so as not to produce any torque at the second angular end position.

Rotary clamping cylinder actuator

Cylinder tube for clamp cylinder

An actuator device includes a housing having a bore and an internal moving body movable within the bore in the direction along the center axis of the bore. The housing is composed of two housing members which divide the housing along the center axis. An inner surface which forms a part of the wall of the bore and two slit surfaces on both sides of the inner surface are formed on each of the housing members. When two housing members are coupled to each other by fastening the longitudinal portions of the housing members by end members, two slits extending along the entire length of the housing are defined by the slit surfaces of two housing members. Since the respective housing members have relatively simple cross sectional shapes, the housing members can be easily produced, by an extrusion process or a drawing process, at low cost. Further, since two slits are provided on the housing, an external moving body can be connected to the internal moving body by two driving members. Thus, the external force exerted on the external moving body is distributed to two driving members, whereby the strength of the actuator device is increased.

Actuator device

A rodless cylinder is coupled to an elongated base. The construction for coupling the rodless cylinder to the base includes a hollow duct formed in the bottom wall of the base and extending along the entire length of the base. A projection extending along the entire length of the duct is formed on the upper inner wall of the duct when the base and duct are formed by a drawing or extrusion process. After the base is formed, the longitudinal ends of the projection are cut off by a predetermined length from both longitudinal ends of the base. The portions of the duct from which the projections are cut off act as receiving portions into which mounting nuts are inserted, and the end faces of the remaining projection act as stoppers which abut the inserted mounting nuts to position them. The upper walls of the duct above the receiving portions are cut off to form slits opening to the upper face of the base. The slits act as mounting bolt passages of the rodless cylinder. The rodless cylinder is coupled to the base by inserting mounting bolts through bolt holes on end caps disposed on both ends of the cylinder. The bolts further pass through the slits and engage the mounting nuts placed in the receiving portions. By tightening the mounting bolt, the rodless cylinder is firmly coupled to the base.

Coupling construction between an actuator and a base

An inner seal band having flat surfaces on both sides is used for closing a slit formed on the cylinder tube of a rodless cylinder. An internal moving body is disposed in the cylinder tube and moves along the longitudinal axis of the cylinder tube. The inner seal band passes through a channel groove formed on the bottom face of the internal moving body. Thin plate-like abrasion members made of synthetic resin are adhered on the side walls of the channel groove. The abrasion members contact with the edges of the inner seal band and restricts its movement in the transverse direction. Since the abrasion members are separate members from the side walls of the channel groove, a material different from that of the side walls, such as abrasion resistant material can be used for the guide members. Further, the thickness of the guide members can be selected in accordance with the actual width of the channel groove and the difference in the width of the channel groove due to machining tolerance can be compensated for by using the guide members having appropriate thicknesses.

The elastomer dampers are disposed at both ends of the actuator cylinder in order to stop the piston moving in the cylinder at its stroke ends. The elastomer damper includes a pair of the protruding portions which abut the piston at its stroke end. The protruding portion has an tapered shape in which the cross sectional area thereof gradually decreases from the base to the top. Therefore, when the piston abuts the protruding portions and compresses the protruding portions, the braking force exerting on the piston gradually increases without sudden change. Therefore, the piston decelerates smoothly at its stroke ends. Further, since the top surface of the protruding portion is formed as a flat plane and the top surface is connected to the tapered side surface of the protruding portion by a round surface, no stress concentration occurs at this portion. Therefore, cracks or breakage of the material do not occur in the top surface even after a long operating time of the actuating cylinder.

Elastomer damper for an actuator cylinder

A rodless power cylinder includes a tube having an oblong circular cross section bore and a slit extending along the longitudinal axis of the bore and penetrating the wall of the tube. The bore includes a slit-side inner surface on which the slit opens and a counter-slit-side inner surface which opposes the slit-side inner surface. The slit-side inner surface of the bore is formed as a flat plane or a curved plane having substantially no curvature. Further, recesses are formed on the slit side inner surface at both sides of the slit. The surfaces of the recesses are formed as curved planes having a curvature larger than the curvature of the slit-side inner surface. An inner seal band made of a flat, thin metal band is provided to seal the opening of the slit. The seal band contacts the surface of the recess at its transverse edges. Therefore, a good sealing capability is achieved by the contacts between the surfaces of the recesses and the edges of the seal band.

Rodless power cylinder

The linear actuator includes a tube provided with a slit which penetrates the wall of the tube and extends parallel to the longitudinal axis of the tube. In the tube, an internal moving body is disposed. The internal moving body moves in the tube along the direction of the longitudinal axis of the tube. An external moving body is disposed outside of the tube and coupled to the internal moving body by a driving member through the slit in the tube so that the external moving body moves integrally with the internal moving body along the slit. Band guides for guiding an outer seal band and an inner seal band are attached to the external moving body. Slider members are disposed between the external moving body and the outer wall surface of the tube to avoid direct contact between the external moving body and the tube. The band guide and the slider member are formed as an integral one-piece element. Therefore, when the band guide is attached to the external moving body, the slider member is simultaneously attached to the external moving body and firmly held in place.

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Ichinomiya, Japan

Mitsuo Noda