JPH0540687Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a drive mechanism. Specifically, the present invention relates to a structure for fixing a motor and a gear driven by the rotation of the motor to a frame.

[Prior Art] For example, a paper feeding mechanism for a printer uses a drive mechanism in which a motor and a gear train for transmitting rotation of the motor to a platen gear or a tractor gear are fixed to a frame.

Conventionally, in order to fix a motor to a frame, multiple screw holes are drilled in the frame, and multiple through holes corresponding to the screw holes are formed in the flange of the motor, and each of the through holes corresponds to a screw hole. In this state, a set screw was passed through the through hole and screwed into the screw hole, and both were tightened and fixed.

Furthermore, in order to fix the frame gear train, studs are integrally formed or press-fitted into the frame itself, and each gear is attached to the studs. Alternatively, when the gear train is configured as a gear block, the gear block is fixed to the frame using a set screw.

[Problems to be solved by the invention] Conventionally, the motor and gear block were fixed to the frame using set screws, but this had the disadvantage of poor work efficiency and increased man-hours.

In particular, when fixing the gear train, it is difficult to integrally form or press-fit studs into the frame itself because the frame itself is large enough to support other parts. In addition, if a product becomes defective during the process of press-fitting the stud,
There was a problem in that not only the frame itself but also all the processing steps that had been performed on the frame before that were wasted.

The purpose of the present invention is to provide a drive mechanism that can solve these conventional problems and easily and efficiently fix a motor and a gear driven by the motor to a frame. be.

[Means for Solving the Problems] Therefore, in the present invention, in a drive mechanism in which a motor and a gear driven by the rotation of the motor are respectively fixed to a frame, the motor mounting surface of the frame is fixed to the frame. A plurality of hooks having clamping pieces facing each other with a certain gap are provided, and the motor is provided with a plurality of mounting portions that are insertably inserted between the motor mounting surface of the frame and the clamping pieces, and the A gear support member is interposed between the motor mounting surface of the frame and the mounting portion, the gear support member having a protrusion that urges the mounting portion toward the holding piece and a stud that supports the gear.
It is characterized by

[Operation] When the gear support member is assembled into the motor mounting surface of the frame, and then the motor mounting part is forcibly inserted into the gap between the gear support member and the clamping piece of the hook, the motor mounting part is attached to the gear support member. At the same time, the gear support member is held and fixed between the frame and the motor, so the gear can be supported by the studs of the gear support member. Bye.

Therefore, when fixing the motor, it is only necessary to forcibly insert the mounting portion of the motor into the gap between the clamping pieces of the hook, so that the motor can be fixed to the frame easily and efficiently. In addition, when fixing the gear, it is only necessary to support the gear on the studs of the gear support member held between the motor and the frame, so the gear can be easily and efficiently attached to the frame. Can be fixed.

[Embodiment] Hereinafter, an embodiment in which the present invention is applied to a paper feeding mechanism of a printer will be described with reference to the drawings.

In a printer's paper feed mechanism, the minimum paper feed amount differs depending on the number of pins on the print head. For example, if the print head has 9 pins, the minimum paper feed amount is 1/144'', and if the print head has 24 pins, the minimum paper feed amount is 1/180''.

For models with different minimum paper feed amounts, it is necessary to change the mounting position of the motor that drives the platen gear or tractor gear that feeds the paper, and the gear train that transmits the rotation of this motor to each gear depending on the minimum paper feed amount.

First, the drive mechanism for 9 pins and the drive mechanism for 24 pins will be explained with reference to FIG.

In the drive mechanism in the case of 9 pins, a motor gear a is arranged around _A1 , and the rotation of this motor gear a is decelerated by a reduction gear _b1 around _B1 and transmitted to the platen gear d. Further, the rotation of the motor gear a is reduced by a reduction gear b ₁ and transmitted to the tractor gear e via an idler gear c ₁ centered around C ₁ .

In the drive mechanism for 24 pins, a motor gear a is arranged around _A2 , and the rotation of this motor gear a is decelerated by a reduction gear _b2 around _B2 and transmitted to the platen gear d. Further, the rotation of the motor gear a is reduced by a reduction gear b ₂ and transmitted to the tractor gear e via an idler gear c ₂ centered on C ₂ .

Therefore, in the drive mechanism for 9 pins and the drive mechanism for 24 pins, the center position of motor gear a
A ₁ , A ₂ , center position B ₁ of reduction gears b ₁ , b ₂ ,
B ₂ and idler gear c ₁ , c ₂ center position C ₁ , C ₂
Since the motors are different from each other, the shapes of the frame that supports them and the mounting part of the motor usually have to be changed.

In this embodiment, even if the minimum paper feed amount is different, the frames and motors can be used in common without changing the frame and motor.

That is, as shown in FIG. 1, the drive mechanism of this embodiment includes a frame 11, a stepping motor 31 fixed to the frame 11, and the gear
The gear support member 41 ₁ supports _{the gears b 1 and c 1 and the} gear support member 41 ₂ supports the gears b 2 and c ₂ .

The frame 11 has elongated holes 12 centered on the center positions A ₁ and A ₂ of the motor gear a, elongated holes 13 centered on the center positions B ₁ and B ₂ of the reduction gears b ₁ and b ₂ , and the idler gear. Elongated holes 14 are formed around center positions C _{1 and} C 2 of c ₁ and c _2, respectively, and hooks 15 and 1 for fixing the motor 31 are provided at four locations around these holes.
6, 17, and 18 are provided, respectively. In addition, 19 and 20 are bosses provided at diagonal positions across the long hole 12, and the gear support members 41 ₁ ,
This is for positioning the 41 ₂ .

Each of the hooks 15 to 18 is connected to the motor mounting surface 11A of the frame 11, as shown in FIGS. 2 and 3.
It is cut and raised into a shape having a clamping piece 21 that faces with a certain gap between them. In other words, a pair of hooks 15 and 16 facing each other with the elongated hole 12 in between has a substantially L-shaped clamping piece 21 formed from the frame 11. Spherical projections 22 and 23 are integrally formed on the inner surfaces of the holding pieces 21 and 21. The other pair of hooks 17 and 18 facing each other across the elongated hole 12 are formed in a box shape with the clamping pieces 21 and 21 as upper walls and openings on opposing surfaces and one diagonal surface, respectively. . A mountain-shaped protrusion 24 is integrally formed on the inner surface of the holding pieces 21, 21.

The stepping motor 31 has the motor gear a attached to the output shaft 33 of the motor 31, and the motor mounting surface 11A of the frame 11 and the hooks 15 to 18 at four locations around the stepping motor 31.
Attachment part 34 that can be inserted into the gap between the clamping piece 21 of
A mounting member 38 having .about.37 is attached. Note that 32 is a bearing sleeve of the output shaft 33.

Among the mounting parts 34 to 37, a pair of mounting parts 34 and 35 facing each other with the output shaft 33 in between has a diameter slightly smaller than that of the projections 22 and 23 of the clamping piece 21 and engages with the projections 22 and 23. a mating engagement hole 39,
40 is formed. Each engagement hole 39, 40 is
They are provided at positions 180 degrees apart from the output shaft 33 and at different distances from the output shaft 33, respectively. Here, Figures 4 and 5
As shown in the figure, the engagement hole 39 is located at the center of the output shaft 33.
The distance to the center of the output shaft 33 is L ₁ , the distance from the axis of the output shaft 33 to the center of the engagement hole 40 is L ₂ , and the distance L ₁
-L ₂ difference is the center position A ₁ , A ₂ of the motor gear a
is set to be equal to the distance between

The gear support members 41 ₁ and 41 ₂ are assembled with one selected depending on the minimum paper feed amount interposed between the frame 11 and the motor 31. Here, the gear support member 41 ₁ is selected in the case of 9 pins, and the gear support member 41 ₂ is selected in the case of 24 pins.

The gear support member 41 ₁ has positioning holes 42 ₁ , 43 ₁ formed at diagonal positions thereof to fit into the bosses 19 , 20 of the frame 11 , and the positioning holes 42 ₁ , 43 ₁ fit into the bosses 19 , 20 of the frame 11 . , 20, the guide hole 4 is sized to fit the bearing cylinder 32 of the stepping motor 31 at a position corresponding to the center position _A1 of the motor gear a.
4 ₁ is formed. Further, on the side of the motor 31 that is in contact with the mounting member 38, the motor 31 is
Spherical projections 45 ₁ to 48 ₁ are integrally provided to urge the mounting member 38 to the clamping pieces 21 of each of the hooks 15 to 18. Further, on the opposite side thereof, there are studs 49 ₁ , 50 ₁ that support the gears _{b 1} , c ₁ at positions corresponding to the center positions B ₁ , C ₁ of the reduction gear b ₁ and idler gear c 1 .
are protruding from each.

The gear support member 41 ₂ has positioning holes 42 ₂ , 43 ₂ formed at diagonal positions thereof to fit into the bosses 19 , 20 of the frame 11 , and these positioning holes 42 ₂ , 43 ₂ fit into the boss 19 . , 20, the guide hole 4 is sized to fit the bearing cylinder 32 of the stepping motor 31 at a position corresponding to the center position _A2 of the motor gear a.
4 ₂ is formed. Further, on the side of the motor 31 in contact with the mounting member 38, the motor 31
Spherical projections 45 ₂ to 48 ₂ that urge the mounting member 38 to the clamping pieces 21 of each of the hooks 15 to 18 are integrally provided. Further, on the opposite side thereof, there are studs 49 ₂ , 50 ₂ that support the gears b _{2 ,} c ₂ at positions corresponding to the center positions B ₂ , C ₂ of the reduction gear b 2 and idler gear c ₂ .
are protruding from each.

Next, the operation of this embodiment will be explained.

When configuring a drive mechanism for 9 pins, a gear support member 41 ₁ is used. The studs 49 ₁ , 50 ₁ of the gear support member 41 ₁ are inserted into the long holes 13 , 50 1 of the frame 11 .
When the positioning holes 42 ₁ and 43 ₁ are fitted into the two bosses 19 and 20 of the frame 11 while inserting the gear support member 41 ₁ into the frame 11 position.

Subsequently, the stepping motor 31 is set to the state shown by the two-dot chain line in FIG. At this time, the bearing sleeve 32 of the stepping motor 31 is attached to the gear support member 41.
It is in a state where it is fitted into the guide hole 44 ₁ of No. ₁ . In this state, the stepping motor 31 is rotated counterclockwise in FIG.
4 to 37 are forcibly inserted into the gaps between the motor mounting surface 11A of the frame 11 and the clamping pieces 21 of the respective hooks 15 to 18.

Then, the engagement holes 39, 40 of the mounting parts 34, 35
engages with the protrusions 22 and 23 of the clamping piece 21,
A stepping motor 31 is positioned relative to the frame 11. In this state, the gear support member 4
The mounting portions 34 to 37 of the stepping motor ₃₁ are connected to the respective hooks 15 to 1 by the protrusions 45 ₁ to 48 ₁ of 1 1.
8, the stepping motor 31 is securely fixed to the frame 11 without play.

Finally, when the reduction gear b ₁ and the idler gear c ₁ are supported by the studs 49 ₁ and 50 ₁ protruding from the back side of the frame 11, the reduction gear
b ₁ is connected to motor gear a and platen gear d, idler gear c ₁ is connected to reduction gear b ₁ and tractor gear e
They are in a state of engagement with each other.

Therefore, the rotation of the stepping motor 31 can be transmitted to the platen gear d via the motor gear a and the reduction gear _b1 , and the rotation of the reduction gear _b1 can be transmitted to the tractor gear _e via the idler gear c1.

On the other hand, when configuring a drive mechanism for 24 pins, a gear support member 41 ₂ is used. In this case, after positioning the gear support member 41 ₂ on the frame 11 in the same manner as above, the stepping motor 31
is set to the state shown by the two-dot chain line in FIG. In other words, the stepping motor 3
Set the mounting angle of step 1 to be rotated 180 degrees. At this time, the bearing sleeve 32 of the stepping motor 31 fits into the guide hole 44 ₂ of the gear support member 41 ₂ in the same manner as described above.

In this state, the stepping motor 31 is rotated counterclockwise in FIG. Forcibly insert it into the gap between.

Then, as shown in FIG.
The engagement holes 39 and 40 of 5 are connected to the projections 22 of the clamping piece 21,
23, so that the stepping motor 31 is positioned relative to the frame 11, and
The mounting portions 34 to 37 of the stepping motor ₃₁ are fixed in a biased state to the clamping pieces 21 of the respective hooks 15 to 18 by the protrusions 45 ₂ to 48 ₂ of the gear support member 41 2 .

At this time, the output shaft 3 of the stepping motor 31
The engagement holes 39, 4 of the mounting parts 34, 35 from the axis of 3
The difference between the distances L ₁ and L ₂ to the center of 0 is the motor gear a
The center position of the motor gear a of the output shaft 33 is equal to the distance between A ₁ and A ₂ , so the center of the motor gear a of the output shaft 33 is
It will be located at _A2 .

Finally, when the reduction gear b ₂ and the idler gear c ₂ are supported by the studs 49 ₂ and 50 ₂ protruding from the back side of the frame 11, the reduction gear
b ₂ is connected to motor gear a and platen gear d, idler gear c ₂ is connected to reduction gear b ₂ and tractor gear e
They are in a state of engagement with each other.

Therefore, the rotation of the stepping motor 31 can be transmitted to the platen gear d via the motor gear a and the reduction gear _b2 , and the rotation of the reduction gear _b2 can be transmitted to the tractor gear _e via the idler gear c2.

Therefore, according to this embodiment, if the gear support members 41 ₁ and 41 ₂ are prepared for each model with a different minimum paper feed amount, the frame 11 and stepping motor 31 can be used in common without replacing them. can be used.

Further, the frame 11 is provided with a plurality of hooks 15 to 18 having clamping pieces 21 facing the motor mounting surface 11A of the frame 11 with a certain gap, and the stepping motor 31 is provided with a plurality of hooks 15 to 18. Attachment part 34 that can be inserted into
A mounting member 38 having .about.37 is provided, and the frame 1
1 with the gear support member 41 ₁ or 41 ₂ installed, attach each mounting portion 34 to 37 to the hook 15 to
18, and urge the stepping motor 31 to the clamping piece 21 of each hook 15 to 18 using the protrusion _{45 1} to 48 ₁ or 45 ₂ to 48 ₂ of the gear support member 41 1 or 41 ₂ . Since the stepping motor 31 is fixed to the base plate, the stepping motor 31 can be fixed easily and efficiently.

In addition, protrusions 2 are provided on the gripping pieces 21 of the hooks 15 and 16.
2 and 23 are provided, and engagement holes 39 and 40 that engage with the protrusions 22 and 23 are formed in the attachment parts 34 and 35, so the attachment parts 34 to 37 can be attached to the hooks 15 to 1
8, the engaging holes 39 and 40 engage with the protrusions 22 and 23, so that the stepping motor 31 can be positioned with respect to the frame 11. Moreover, each gear support member 41 ₁ , 41 ₂ has guide holes 44 ₁ , 44 2 formed therein so as to fit into the bearing sleeve 32 of the stepping motor 31, so positioning can also be performed using these guide holes 44 1 , 44 ₂ . can.

Furthermore, since the distances L ₁ and L ₂ from the axis of the output shaft 33 of the stepping motor 31 to the centers of the engagement holes 39 and 40 of the mounting parts 34 and 35 are formed to be different, the mounting of the stepping motor 31 is angle 180
By rotating the output shaft 33 by a certain degree, the position of the output shaft 33 can be changed. Therefore, the stepping motor 31 can be applied to different models without changing the shape of the mounting portion of the stepping motor 31.

The gear support members 41 ₁ and 41 ₂ also have reduction gears b ₁ and 41 2 at gear mounting positions corresponding to each model.
Since the studs _{49 1 ,} 50 ₁ , 49 ₂ , 50 ₂ that support b ₂ and idler gears c 1 , c ₂ are provided protrudingly, installation of these reduction gears b ₁ , b ₂ and idler gears c ₁ , c ₂ is easy and It can be done efficiently.

In the above embodiment, the frame 11 is provided with four hooks 15 to 18, and the stepping motor 31 is provided with the number of attachment parts 34 to 37 corresponding to the hooks 15 to 18. The number may be at least 2 or more. If the number of hooks and attachment parts is 2 or 3, the stepping motor 31 is not rotated, but
Each attachment part can be inserted into the hook by sliding it laterally.

Furthermore, in the above embodiment, the stepping motor 3
1 rotation to the platen gear d and the tractor gear e, two studs 49 _{1 ,} 50 ₁ , 49 ₂ , 50 ₂ were provided protruding from each gear support member 41 1 , 41 ₂ . If the rotation of the gear 31 needs to be transmitted only to one of the gears d and e, only one stud may be used. Furthermore, a drive gear may be attached directly to one of the studs.

Further, in the above embodiment, the drive mechanism in the paper feed mechanism of a printer was explained, but the present invention is not limited to this, and can be applied to drive mechanisms in general that drive gears by rotation of a motor. .

[Effects of the invention] As described above, according to the invention, when fixing the motor, it is only necessary to insert the mounting part of the motor into the gap between the clamping pieces of the hook, so that the motor can be easily and efficiently attached to the frame. can be fixed to. Also,
When fixing the gear, it is only necessary to support the gear on the studs, so the gear can be fixed to the frame easily and efficiently.

[Brief explanation of drawings]

The figures show one embodiment of the present invention, in which Fig. 1 is an exploded perspective view, Fig. 2 is a cross-sectional view of the frame, and Fig. 3 is a view showing a state in which the motor and gear support member are assembled in the frame. Figure 4 is a diagram showing the state of engagement between the motor and each hook of the frame, Figure 5 is a diagram showing the state in which the mounting angle of the motor has been rotated 180 degrees with respect to the state in Figure 4, and Figure 6 is a diagram showing the state in which the motor is engaged with each hook of the frame. FIG. 3 is a diagram showing a drive mechanism in a paper feeding mechanism of a printer. 11...Frame, 15-18...Hook, 2
1... Clamping piece, 31... Stepping motor, 3
4-37... Mounting part, 41 ₁ , 41 ₂ ... Gear support member, 45 ₁ - 48 ₁ , 45 ₂ - 48 ₂ ... Projection, 4
9 ₁ , 50 ₁ , 49 ₂ , 50 ₂ ... Stud.

Claims (1)

[Claims for Utility Model Registration] In a drive mechanism in which a motor and a gear driven by the rotation of the motor are respectively fixed to a frame, the motor mounting surface of the frame faces the frame with a certain gap therebetween. a plurality of hooks each having a clamping piece that connects the frame; A drive mechanism characterized in that a gear support member is interposed between the mounting portion and the gear support member having a protrusion that urges the mounting portion toward the holding piece and a stud that supports the gear.