TWI487545B - Electric injection device for linear dental - Google Patents

Description

Linear dental electric injection device

The present invention relates to a dental electric injection device for injection of an injection such as an anesthetic in dental treatment, particularly a linear dental electric syringe.

The injection of an anesthetic agent in dental treatment has been carried out in recent years using a sputum electric injection device. The applicant of the present invention has developed a shovel-type electric injection device as described above and has been widely used, and the device has been disclosed as Japanese Laid-Open Patent Publication No. 2001-70444 (Patent Document 1). The cymbal syringe disclosed in Patent Document 1 includes a pinion that rotates by a planetary gear mechanism that is a reducer by a motor with a reducer, and a ejector that meshes with the pinion. The pusher is a rubber plunger that is filled with the sputum of the injection liquid by the forward movement from the initial position, and the injection liquid is ejected from the injection needle of the rubber plug that pierces the sputum. In order to inject the injection into the oral cavity, the advancement of the pusher is performed at an extremely slow moving speed of 30 mm / 60 seconds, 30 mm / 100 seconds, 30 mm / 200 seconds. When the operation of the injection is completed, the push rod must be retracted. The action is formed: the push rod can be freely moved by hand by interrupting the connection between the pinion meshing with the rack of the push rod and its driving mechanism. Push back to the initial position.

There are two problems to be solved in the electric injector of the above configuration. One of them is: when the front end of the push rod is pressed against a rubber plunger made of glass filled with a liquid medicine, although it is extremely rare, it sometimes deviates from its center position. Moving into contact with the inner wall of the glass tube causes cracking of the glass tube. The inventors of the present invention have found that one of the causes of the above-mentioned cracking is the rack-and-pinion mechanism. Since the push rod requires a sending force of 300 N (about 30 kg) (that is, a discharge pressure of the chemical liquid at the time of injection), when the push rod advances while maintaining the above pressure, the motor vibrates in a direction of being detached from the load, and The tip end of the rack of the push rod propelled by the "pinion gear driven by the motor" acts to maintain the force at the 90° position, and the front end of the push rod is disengaged from the specific rectilinear position. That is, the front end of the push rod is displaced from its center position with respect to the rubber plunger of the crucible. Another problem is that the planetary-gear mechanism is used as a speed reducer, and the drive structure of the rack-and-pinion is complicated. Moreover, the means for interrupting the connection between the pinion and the drive mechanism becomes a complicated structure. The disadvantages of the class.

[Patent Document 1] Japanese Patent Laid-Open No. 2001-70444

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary shaft and a push rod which are a motor (reduction motor) to which a reducer is attached as an engine, and which can be arranged in a straight line by a simple mechanism to solve the forward drive of the push rod. The linear dental electric injection device of the above-mentioned problem.

Another object of the present invention is to provide a linear dental electric injection device that simply pushes the push rod back to its initial position when the injection operation is completed by a simple mechanism.

According to the present invention, there is provided a linear dental electric injection device, the linear dental electric injection device comprising a housing for fixing a power injector unit, the power injector unit comprising: a fixed housing, the fixed housing at the front end The utility model has a cylindrical space for inserting the bearing socket, and has a connector for detachably connecting the bearing seat inserted into the cylindrical space, and a motor with a reducer is coupled at the rear end (deceleration) a push rod having a male thread, the push rod having a male thread forming a line with the drive shaft, and configured to be movable in a non-rotational manner in a long axis direction; and a rotating barrel, the rotating barrel being in the box The body is disposed coaxially with the drive shaft of the motor and coupled to the drive shaft of the motor and rotated by the drive shaft; and the nut is formed by a pair of arm-shaped nut halves facing each other, The pair of rear half arms of the arm nut half opposite to each other are rotatably attached to the rotating cylinder and protrude forwardly beyond the front end of the rotating cylinder, and have a male thread with the push rod on the front inner surface a female thread; and a lock ring configured to move between a rearward position of the "the female thread of the arm nut half and the male thread of the push rod" and the forward position to release the engagement a long axis direction and rotatable; and a bushing pin that is pressed by the yoke when the yoke is inserted into the cylindrical space and is coupled to the cylindrical space to cause the lock ring to move from the front position to a rear position; and a coil spring that presses the lock ring back to the front position when the bearing seat is not inserted into the cylindrical space; and causes the nut to rotate around the push rod by utilizing the rotation of the rotating cylinder, thereby Push the putter forward.

According to the present invention, the push rod having the male thread preferably has: a flat surface opposite to each other in the axis direction of the shaft; the fixing box is provided with a guiding hole having a cross-sectional shape conforming to the cross-sectional shape of the push rod, and the push rod is passed through the push rod Movement in the long axis direction in the rotated state becomes possible.

Preferably, the arm nut half has an outer circular arc surface having an inclined circular arc surface at a front protruding portion thereof, and a flat surface parallel to the long axis direction, and is disposed in a groove hole formed in a front portion of the rotary cylinder Internally, and rotatably coupled to the rotating cylinder by a pivot pin. Preferably, the lock ring has an inner cylindrical surface which is a front projection for receiving the half of the arm nut and has an outer circular surface that engages with the half of the arm nut at the rear position. The inclined cam surface of the inclined circular surface; and the front end of the lock ring is provided with a thrust bearing for rotational contact with the end surface of the operating pin. a coil spring, wherein one end is engaged with a protrusion formed at a rear end of the arm nut half, and the other end is engaged with a seat formed at a rear end of the lock ring, and in a normal state, the arm nut half The portion is pushed outward in the radial direction, and the lock ring is pushed toward the front position, and the female thread of the arm nut half is separated from the male thread of the push rod.

In a preferred embodiment of the present invention, the power transmission mechanism for transmitting the rotation of the drive shaft to the rotary cylinder is further included, and the power transmission mechanism is formed by a flat cam surface facing each other, which is opposite to each other. a flat cam surface formed at a front end portion of the drive shaft; and an annular outer circumferential groove formed at a rear end portion of the rotating cylinder; and a hole formed in the outer circumferential groove; and a locking ball, The locking ball is received in the hole; and the annular torsion band having a notch, the annular torsion band that pushes the locking ball toward the flat cam surface, and is surrounded by a leaf spring that is fitted into the annular outer circumferential groove form.

Referring to the drawings, in particular, FIGS. 1 and 2, the linear dental electric injection device of the present invention is generally indicated by reference numeral 10 and includes a housing 14 that is fixed and houses the power injector unit 12. The outer casing 14 includes a battery case 18 for housing a battery 16 as a power source. The power injector unit 12 includes a fixed case 20 having a cylindrical space 24 at the front end thereof into which the socket 22 can be inserted, and a detachable connection of the cymbal holder 22 inserted into the cylindrical space 24 At the connector 26 there, a motor (reduction motor) 28 to which a reducer is attached is fixed to the rear end of the casing 20. The drive shaft 30 is coupled to the rotation shaft of the reduction motor 28, and is rotatably supported by a bearing 21 provided in the casing 20. The push rod 32 having a male thread is aligned with the axis of the rotary shaft. The ground is disposed in the long axis direction of the injection device. The push rod 32 has a head portion 33 at the front end and has a small male thread 34 having a pitch throughout its entire length, and a flat side surface 36 opposed to each other parallel to the axis of the long axis direction. The fixing case 20 is provided with a guiding hole 38 having a cross-sectional shape conforming to the cross-sectional shape of the push rod 32, that is, the guiding hole 38 is formed by a circular arc surface facing each other and parallel sides facing each other. By pushing the push rod 32 through the guide hole 38, the push rod 32 can be non-rotatably moved in the long axis direction (refer to Fig. 6). The rotary cylinder 40 is a drive shaft 30 that is disposed coaxially with the drive shaft 30 of the motor and that is coupled to the motor through the power transmission mechanism 42 and has a long axis that can coaxially receive the push rod 32. The pupil 44 to the direction. Reference numeral 39 is a thrust bearing which can form a rotational contact with the end surface of the rotary cylinder 40.

Referring to FIGS. 2, 3, and 7, the power transmission mechanism 42 is configured by a flat cam surface 46 that faces each other, and the flat cam surface 46 that faces each other is formed at the front end portion of the drive shaft 30. And an annular outer circumferential groove 48 formed at a rear end portion of the rotating cylinder 40; and a hole 50 formed in the outer circumferential groove 48; and a locking ball 52, the locking ball 52 The annular torsion belt 54 is received in the hole 50; and the notched annular torsion band 54 is fitted to the annular outer circumferential groove 48 and formed by a leaf spring. During the operation, the flat cam surface 46 of the drive shaft 30 is slightly forward of the arcuate outer peripheral surface 47 (a position having a large radius from the axis of the drive shaft 30) and is engaged with the locking ball 52. The notched annular torsion band 54 is expanded, and the spring action generated by the foregoing action causes the locking ball 52 to be pressed against the position of the flat cam surface 46, so that the drive shaft 30 is coupled to the rotating cylinder 40, and The rotation of the drive shaft 30 is transmitted to the rotary cylinder 40. When an excessive load is generated, since the rotation of the rotary cylinder 40 is prevented, a relative rotational movement is initiated between the rotary cylinder and the drive shaft 30 of the motor 28, so that the arcuate outer peripheral surface 47 of the drive shaft 30 resists The spring of the notched annular torsion band 54 is rotatably contacted with the locking ball 52, and then the flat cam surface 46 of the drive shaft 30 faces the locking ball 52, thereby causing the locking ball 52 to fall into the flat cam surface 46. The above-described continuous operation causes the drive shaft 30 to continuously idling the rotary cylinder 40 in a state where the rotation of the drive shaft 30 is not transmitted to the rotary cylinder 40.

It can be clearly seen from Fig. 3, Fig. 4 and Fig. 5 that a pair of each other A nut 57 formed by the opposing arm nut half 56 is provided in the rotating cylinder 40. Each of the arm-shaped nut halves 56 has an outer circular arc surface 58 and a flat surface 60 that is parallel in the long-axis direction, and is formed in the long-axis direction of the front portion of the rotary cylinder 40 due to the flat surface. The inside of the groove hole 62 is disposed so as not to rotate, and is rotatably coupled to the rotating cylinder 40 by the lateral pivot pin 64. The arm nut half 56 protrudes forward from the front end surface of the rotating cylinder 40, has an inclined circular arc surface 66 at the front protruding portion, and has a female meshing engagement with the male screw 34 of the push rod 32 on the front inner surface. Thread 68. The lock ring 70 has an inner cylindrical surface 74, and the inner cylindrical surface 74 is provided with an inclined cam surface 72 which can receive the front projection of the arm nut half 56 and can be engaged with the arm screw The inclined circular surface 66 of the cap half 56. The lock ring 70, in order to engage the female thread 68 of the arm nut half 56 with the male thread 34 of the push rod 32, may be in the "inclined cam surface 72 that allows the arm nut half 56 to rotate toward the push rod 32, Engaged between the rearward position of the inclined circular arc surface 66" of the arm nut half 56 and the front position of the "engagement of the engagement between the inclined cam surface 72 and the inclined circular arc surface 66 in order to release the engagement" The movement is in the longitudinal direction and is rotatably fitted to the cylindrical inner surface 25 of the fixed casing 20.

As shown in FIGS. 2 and 6, the plurality of bushing pins 75 are inserted: pin holes 76 formed in the circumferential direction at equal intervals on the fixed casing 20, and the length of each pin is: when the bearing When the seat 22 is inserted into the cylindrical space 24 and is coupled to the cylindrical space 24, it is pressed by the end surface of the cymbal holder 22 to urge the lock ring 70 to move from the front position to the rear position. Preferably, the lock ring 70 is provided at a front end thereof for rotating between the end faces of the bushing pins 75. Thrust bearing 78 that is touched. Further, a coil spring 80 is provided which presses the lock ring 70 forward when the yoke seat 22 is not inserted into the cylindrical space 24, that is, in a normal state. One end of the coil spring 80 is engaged with the protruding portion 59 formed at the rear end of the arm nut half 56, and the other end is engaged with the seat portion 71 formed at the rear end of the lock ring 70. In the normal state, the arm is the arm. The nut half 56 is urged radially outwardly with its thread 68 separated from the thread 34 of the push rod 32.

Reference numeral 82 is a switch for starting the motor 28. The outer casing is preferably formed of a plastic material, and the above-described constituent members of the electric injector unit 12 are made of metal.

Hereinafter, the operation of the electric injection device of the present invention will be described. Since the cymbal holder 22 is not inserted into the cylindrical space 24 of the fixed casing 20, the lock ring 70 is located at the front position, so that the bushing pin 75 is pushed forward and is in a standby state in the cylindrical space 24 of the fixed casing 20. The push rod 32 temporarily retreats to the initial position. When the connector 26 is operated, the cymbal holder 22 accommodating the medicinal liquid filling cartridge 84 is inserted into the cylindrical space 24 of the fixed casing 20 and coupled thereto, and the cymbal holder 22 presses the bushing pin 75 from the rear end surface thereof. The lock ring 70 is caused to move from the front position to the rear position against the action of the coil spring 80. The inclined cam surface 72 of the lock ring 70 engages with the inclined circular arc surface 66 of the arm nut half 56, causing the arm nut half 56 to rotate toward the push rod 32, thereby making the arm nut half 56 The female thread 68 engages with the male thread 34 of the push rod 32. Prior to the injection operation, it is undoubted that the dental double-ended injection needle (shown in phantom in Figure 1) will be inserted into the sputum 84 and mounted on the pedestal holder 22. Then, the switch 82 is operated to start the motor 28. Once the motor is activated, the rotation of the motor 28 will be transmitted to the rotating cylinder 40 through the drive shaft 30 and the power transmitting mechanism 42. For this reason, since the nut 57 rotates around the push rod 32, the push rod is acted upon by the action of the thread. 32 straight forward at a very low speed. The rubber plunger 86 of the crucible 84 is pressed by the push rod 32, and the chemical liquid is discharged through the injection needle.

In the event that an excessive load is generated by the injection device during the injection operation, as will be explained above, the drive shaft 30 will idle the rotary cylinder 40 without transmitting the rotation to the rotary cylinder 40. By the rotation of the drive shaft 30, the arcuate outer peripheral surface 47 of the drive shaft 30 is rotationally contacted with the locking ball 52, and then the locking ball 52 is pressed by the spring of the annular torsion belt 54 having the notch to be pressed in the radial direction. The inside is dropped into the flat cam surface 46. When the above-described continuous motion is repeated, the sound generated between the metals is emitted from the power transmission mechanism, whereby the user can know that the injection device is in an excessive load state, and operates the switch 82 to stop the rotation of the motor 28.

When the injection operation is completed, the operating connector 26 pulls the cymbal holder 22 out of the cylindrical space 24. As a result, since the press-in of the bushing pin 75 is released, the lock ring 70 is pushed back from the rear position to the front position by the action of the spring 80, and the arm nut half 56 is pivoted by the pivot pin 64. The center is rotated outward in the radial direction, and by the above operation, the female screw 68 of the arm nut half 56 is disengaged from the male screw 34 of the push rod 32. In this way, the pusher 32 that has advanced can be freely returned to its initial position by hand using a pressing device such as a plastic (not shown).

According to the present invention, since the nut can be caused to rotate around the push rod, and the push rod is pushed straight by the above-mentioned thread action, there is no need to attach a reducer The rotation of the motor makes a special reducer for further deceleration.

10‧‧‧Linear Dental Electric Syringes

12‧‧‧Power injector unit

14‧‧‧Shell

20‧‧‧Fixed box

22‧‧‧匣 Bearing

24‧‧‧Cylinder space

26‧‧‧Connector

28‧‧‧Motor with gearbox (gearmotor)

30‧‧‧Drive shaft

32‧‧‧Puts with male threads

34‧‧‧Small pitch male thread

40‧‧‧Rotating cylinder

42‧‧‧Power transmission mechanism

46‧‧‧flat cam surface

48‧‧‧Circular peripheral groove

50‧‧‧ hole

52‧‧‧Card ball

54‧‧‧Round torsion belt

56‧‧‧ Arm nut half

57‧‧‧ nuts

59‧‧‧Protruding

66‧‧‧Slanted arc surface

70‧‧‧Lock ring

71‧‧‧seat

72‧‧‧ tilt cam surface

75‧‧‧ bushing pin

78‧‧‧ thrust bearing

80‧‧‧Helical spring

Fig. 1 is an overall perspective view of a linear dental electric injection device of the present invention.

Fig. 2 is a cross-sectional side view in the longitudinal direction of the dental electric injection device shown in Fig. 1.

Fig. 3 is an exploded perspective view showing a rotating cylinder having a nut formed by a half of an arm nut and a lock ring.

Fig. 4 is a front view of the rotary cylinder and the nut shown in Fig. 3.

Fig. 5 is a longitudinal sectional view showing the relationship between the nut and the lock ring of Fig. 3.

Fig. 6 is a cross-sectional view taken along line 6-6 of Fig. 2.

Fig. 7 is a cross-sectional view taken on line 7-7 of Fig. 2.

10‧‧‧Linear Dental Electric Syringes

12‧‧‧Power injector unit

14‧‧‧Shell

16‧‧‧Battery

18‧‧‧ battery case

20‧‧‧Fixed box

21‧‧‧ bearing

22‧‧‧匣 Bearing

24‧‧‧Cylinder space

25‧‧‧ inside the cylinder

26‧‧‧Connector

28‧‧‧Motor with gearbox (gearmotor)

30‧‧‧Drive shaft

32‧‧‧Puts with male threads

33‧‧‧ head

34‧‧‧Small pitch male thread

36‧‧‧flat side

38‧‧‧ Guide hole

39‧‧‧ thrust bearing

40‧‧‧Rotating cylinder

42‧‧‧Power transmission mechanism

44‧‧‧膛孔

46‧‧‧flat cam surface

48‧‧‧Circular peripheral groove

50‧‧‧ hole

52‧‧‧Card ball

54‧‧‧Round torsion belt

56‧‧‧ Arm nut half

57‧‧‧ nuts

59‧‧‧Protruding

62‧‧‧Ditch hole

64‧‧‧ horizontal sales

66‧‧‧Slanted arc surface

68‧‧‧Female thread

70‧‧‧Lock ring

71‧‧‧seat

72‧‧‧ tilt cam surface

75‧‧‧ bushing pin

76‧‧ ‧ pinhole

78‧‧‧ thrust bearing

80‧‧‧Helical spring

82‧‧‧ switch

84‧‧‧Drug filling 匣

86‧‧‧Rubber plunger

Claims (5)

A linear dental electric injection device, comprising: a housing for fixing a power injector unit, wherein the power injector unit comprises: a fixing box body having a cylindrical space at the front end for inserting the bearing seat And a connector that can detachably couple the cymbal holder inserted into the cylindrical space to the connector, and a motor (reduction motor) with a reducer coupled to the rear end; and a push with a male thread a rod having a male thread formed in line with a drive shaft of the motor and configured to be movable in a non-rotational manner in a long axis direction; and a rotating cylinder configured to be disposed in the fixed casing a drive shaft of the motor is coaxial and coupled to the drive shaft of the motor and rotated by the drive shaft; and a nut formed by a pair of arm-shaped nut halves facing each other, the pair being mutually a rear half of the arm nut half is rotatably coupled to the rotating cylinder and protrudes forward beyond the front end of the rotating cylinder, and has a push rod on the front inner surface a female thread engaged by the male thread; and a lock ring configured to be disposed at a rear position of the "the female thread of the arm nut half is engaged with the male thread of the push rod" and the forward position for releasing the engagement And moving in a long axis direction and rotatable; and a bushing pin that is urged by the socket when the socket is inserted into the cylindrical space and coupled to the cylindrical space The foregoing a locking ring moving from a front position to a rear position; and a coil spring that presses the lock ring back to a front position when the bearing seat is not inserted into the cylindrical space; by utilizing rotation of the rotating drum The nut is caused to rotate around the push rod to promote the advancement of the push rod. The linear dental electric injection device according to claim 1, wherein the arm nut half has an outer circular arc surface having an inclined circular arc surface at a front protruding portion thereof, and a parallel to the long axis direction The arm-shaped nut half is disposed in a groove formed in a front portion of the rotating cylinder, and is rotatably coupled to the rotating cylinder by a pivot pin. The linear dental electric injection device according to claim 1, wherein the lock ring has an inner cylindrical surface that receives a front protruding portion of the arm nut half and has a rearward position An inclined cam surface for engaging an inclined circular arc surface of the outer circular arc surface of the arm nut half. The linear dental electric injection device according to claim 3, wherein the front end of the lock ring is provided with a thrust bearing for rotationally contacting the end surface of the bushing pin. The linear electric injection device according to claim 1, wherein the coil spring has one end that is engaged with a protruding portion formed at a rear end of the arm nut half, and the other end of which is engaged in the aforementioned a seat at the rear end of the lock ring, and in a normal state, the arm nut half is pushed outward in the radial direction, so that the lock ring is pushed to the front position thereof, and the arm nut half is The female thread is separated from the male thread of the aforementioned push rod.