Abstract: The dental handpiece of a center-injection type has a bur sleeve (8, 9) having an axial through hole capable of receiving and detachably holding therein a cutting bur having an axial through hole, upper and lower bearings (10, 11) for rotatably supporting the bur sleeve (8, 9), and an injection nozzle (5) capable of being inserted into the axial through hole of the cutting bur from its proximal end for injecting cooling water through the other end. The dental handpiece (1) further has an upper seal means (17) arranged to seal the space between the upper region of the bur sleeve (8, 9) and the upper bearing (10), and a lower seal means (17?9 arranged to seal the space between the lower region of the bur sleeve (8, 9) and the lower bearing (11).

Abstract: A dental handpiece has a head section, a neck section, a grip section connected to the grip section, and a drive unit connected to the grip section. The handpiece also has a detent unit for preventing relative rotation between the neck and grip sections. The detent unit includes a detent pin arranged axially slidably in the grip section, a spring for biasing the pin proximally so that the distal end of the pin is arranged inside the grip section in a rest position, and a catch formed at the proximal end of the neck section for receiving the pin for engagement. When the drive unit is brought into connection to the grip section, the pin is pressed distally to project out of the grip section into engagement in the catch, to thereby prevent relative rotation between the neck section and the grip section.

Abstract: A dental handpiece where the chip air line is selectively switched to the ON-state for using both water and chip air, and to the OFF-state for using only water. The dental handpiece has a switching valve between the circumferential chip air channel and the chip air line in the handpiece body for selectively allowing and preventing communication. Opening the valve switches the communication to the ON-state in which chip air is allowed to pass from the circumferential chip air channel into the chip air line. Closing the valve switches the communication to an OFF-state in which chip air is prevented from passing from the circumferential chip air channel into the chip air line.

Abstract: A dental handpiece capable of withstanding a higher torque load includes a driving source which rotates a first rotating shaft 3 which is supported rotatably in a rear casing 2R, which transmits rotation to a second rotating shaft 9 which is supported rotatably in a front casing 2F. First and second bearings 12,14 are disposed at a predetermined interval in a jacket 8 fixed in the front casing 2F to rotatably support the second rotating shaft 9, and a third bearing 13 is disposed between the first and second bearings 12,14. The third bearing 13 reduces the whirling of the second rotating shaft 9, thereby preventing the wearing and chipping of the teeth of gears caused by a shift of meshing positions between a first gear 5 and a second gear 10 and a shift of meshing positions between a third gear 11 and a fourth gear 73.

Abstract: A dental handpiece where the chip air line is selectively switched to the ON-state for using both water and chip air, and to the OFF-state for using only water. The dental handpiece has a switching valve between the circumferential chip air channel and the chip air line in the handpiece body for selectively allowing and preventing communication. Opening the valve switches the communication to the ON-state in which chip air is allowed to pass from the circumferential chip air channel into the chip air line. Closing the valve switches the communication to an OFF-state in which chip air is prevented from passing from the circumferential chip air channel into the chip air line.

Abstract: Disclosed is a dental handpiece wherein the chip air line is selectively switched to the ON-state for using both water and chip air, and to the OFF-state for using only water. The dental handpiece has a switching valve provided between the circumferential chip air channel and the chip air line in the handpiece body for selectively allowing and preventing communication therebetween, wherein opening of the valve switches the communication to the ON-state in which chip air is allowed to pass from the circumferential chip air channel into the chip air line, whereas closing of the valve switches the communication to an OFF-state in which chip air is prevented from passing from the circumferential chip air channel into the chip air line.

Abstract: A dental handpiece has a head section, a neck section, a grip section connected to the grip section, and a drive unit connected to the grip section. The handpiece also has detent means for preventing relative rotation between the neck and grip sections. The detent means includes a detent pin arranged axially slidably in the grip section, spring means for biasing the pin proximally so that the distal end of the pin is arranged inside the grip section in a rest position, and catch means formed at the proximal end of the neck section for receiving the pin for engagement. When the drive unit is brought into connection to the grip section, the pin is pressed distally to project out of the grip section into engagement in the catch means, to thereby prevent relative rotation between the neck section and the grip section.

Abstract: A dental handpiece having a grip with a head in which a treatment tool may be detachably attached. A front casing portion of the grip is continuous to a rear casing portion at an obtuse angle. A first rotary shaft is rotatably supported in the rear casing portion. A cylindrical jacket extends from the head and is arranged in the front casing portion toward the first rotary shaft. A second rotary shaft is rotatably supported in the jacket, and is operatively connected to the treatment tool at one end and to the first rotary shaft at the other end via a gear. The rotary shafts transmit driving force to the head section to drive the treatment tool. The jacket is provided with an engagement groove on its circumferential surface. An engaging device disposed in the rear casing portion detachably engages the groove, thereby fixing the jacket in the front casing portion.

Abstract: The dental handpiece of a center-injection type has a bur sleeve (8, 9) having an axial through hole capable of receiving and detachably holding therein a cutting bur having an axial through hole, upper and lower bearings (10, 11) for rotatably supporting the bur sleeve (8, 9), and an injection nozzle (5) capable of being inserted into the axial through hole of the cutting bur from its proximal end for injecting cooling water through the other end. The dental handpiece (1) further has an upper seal means (17) arranged to seal the space between the upper region of the bur sleeve (8, 9) and the upper bearing (10), and a lower seal means (17?9 arranged to seal the space between the lower region of the bur sleeve (8, 9) and the lower bearing (11).

Abstract: A dental handpiece is disclosed which comprises a grip section having a head section in which a treatment tool is detachably attached, and a drive section detachably connected thereto. The grip section comprises a casing having front and rear casing portions, with the front casing portion being continuous to the rear casing portion at an angle; a first rotary shaft rotatably supported in the rear casing portion, a cylindrical jacket extending from the head section and arranged and fixed in the front casing portion toward the first rotary shaft, and a second rotary shaft rotatably supported in the jacket, and operatively connected to the treatment tool at one end and to the first rotary shaft at the other end via a gear. The driving force from the drive section is transmitted by means of the first and second rotary shafts to the head section to drive the treatment tool. The jacket is provided with an engagement groove on its circumferential surface.

Abstract: The present invention relates to a dental head unit capable of measuring a root canal length of a patient. The head unit includes a head section having a sleeve rotatably supported therein for detachably holding a cutting tool therein, a neck section extending proximally from the head section and having a proximal end for connecting to a handpiece body, a contact capable of detachably contacting the cutting tool for providing electric connection to the cutting tool when in contact, and a contact holder fixed to a proximal end of the contact and axially slidable with respect to the neck section. The contact holder has a lead attachment to which a lead for electrically connecting the contact to a root canal length measuring device is detachably attached. The present invention also relates to a contact holder assembly including the contact and the contact holder.

Abstract: The present invention relates to a dental head unit capable of measuring a root canal length of a patient. The head unit includes a head section having a sleeve rotatably supported therein for detachably holding a cutting tool therein, a neck section extending proximally from the head section and having a proximal end for connecting to a handpiece body, a contact capable of detachably contacting the cutting tool for providing electric connection to the cutting tool when in contact, and a contact holder fixed to a proximal end of the contact and axially slidable with respect to the neck section. The contact holder has a lead attachment to which a lead for electrically connecting the contact to a root canal length measuring device is detachably attached. The present invention also relates to a contact holder assembly including the contact and the contact holder.

Abstract: A transmission timing control section latches operational data received from an operating section in timing corresponding to a channel set in a channel setting section, compares the latched operational data and last operational data stored in a temporarily storage section and judges whether or not the latched operational data is identical with the last operational data. In case of the judgment for those to be identical with each other, no transmission instructing signal is outputted, and the transmission of the communication data is stopped in that timing. In case of the judgment for those not to be identical with each other, a transmission instructing signal is outputted from the transmission timing control section to a transmitting section to transmit the communication data in that timing.

Abstract: A connection-fighting type game machine that enables game character progression when game machines are physically connected together. The connection-fighting type liquid crystal game machine may be connected to another game machine of the same kind. Convex and concave sections of the housing of each machine assist in aligning the machines when they are connected together. A growth degree changing processing section improves the growth degree of the character that has gained a victory, performs a growth degree changing processing by leaving as it is or lowering the growth degree of the character that has suffered a defeat.

Abstract: A connection-fighting type game machine and a connection-fighting type game method enable game character progression in an independent use state, or in a connected-fighting use state. The connection-fighting type liquid crystal game machine can be used independently, thereby causing a built-in character to grow according to input information from an operation input section that stores growth degree information of the grown character. The game machine may also be connected to another game machine of the same kind. An outcome processing section reads out the growth degree information of the characters stored in the respective game machines, and then causes them to fight in a predetermined fighting manner. A growth degree changing processing section improves the growth degree of the character that has gained a victory, performs a growth degree changing processing by leaving as it is or lowering the growth degree of the character that has suffered a defeat.

Abstract: A right looper release mechanism in an overlock sewing machine is disclosed comprising a vertically movable needle having a needle thread, a right looper disposed under the vertically movable needle and reciprocally movable in a direction crossing the vertically movable needle, a rear driving lever attached to the right looper and engaged in a right looper shaft so as to be freely turned relative thereto, a front driving lever fixed to the right looper shaft, a fixing screw member inserted in a throughhole of the front driving lever so as to be freely turned, said fixing screw member having a male screw being screwed into a female screw 3a of the rear driving lever so as to transmit a motion of the right looper shaft to the rear driving lever by way of the front driving lever, and an elastic member for elastically biasing the fixing screw member in a direction to release the fixing screw member so as to be unscrewed from the female screw of the rear driving lever.

Abstract: Thread guide devices capable of easily and quickly performing a threading operation with an excellent operability, whereby a thread is hardly come off or entangled, and hence a sewing operation is hardly interrupted when the thread is come off or entangled, leading to an excellent sewing operating performance. Each thread guide device of sewing machine includes a thread guide member disposed between a thread spool and a tension device respectively provided on a body for guiding a thread from the thread spool, and the thread guide member comprises a base end portion attached to one end of a thread guide groove portion which is opened at an upper end of the body, a tip end portion having an inclination portion which is elastically brought into contact with a rear side wall of the body at a front surface of the inclination portion, and a thread accommodation space which is defined in a lower end portion of the thread guide groove portion.

Abstract: A bed structure for an overlock machine comprises a fixed bed formed by connecting an extension bed to a portion of the front side of a main bed, a substantially box-shaped free arm cover transversely slidably and removably disposed contiguously with a main frame beside a throat plate so as to cover a looper; and a substantially U-shaped auxiliary bed having a front portion, a side portion and a rear portion, disposed so as to surround all sides of of the free arm cover excluding one side of the free arm cover adjacent to the main frame with the front portion thereof inserted in a gap between the extension bed and the free arm cover and with the end surfaces of the lower wall and the lower side wall of the side portion thereof in contact with the side surfaces of the main frame and joined to the extension bed with a horizontal land portion formed in the surface of the front portion thereof fitted in a horizontal groove formed in the corresponding surface of the extension bed so as to be transversely movable r

Abstract: A ball conveying game apparatus including a plurality of ball support portions provided on a vertical game board surface, a protrusible and retractable plunger provided at at least one of the ball support members, and a manual operating member such as a pressing member linked on an operational basis to the ball support member through a predetermined interlocking mechanism so that a ball can be transferred from one to another of the ball support members along a ball moving course by operating the manual operating member. The ball is conveyed from a starting point to a goal point by a plurality of choosable ball moving courses arranged in the ball moving course. Selection from among the choosable ball moving courses is made by operating the manual operating member. In playing the ball conveying game apparatus, therefore, a player is required to dexterously manipulate the manual operating member. Various ways of playing are possible.