JP3099443B2 - Shim selection method for gear backlash adjustment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of selecting a shim for adjusting the backlash of a gear, and more particularly to a method of selecting a shim capable of reducing the backlash.

[0002]

2. Description of the Related Art A backlash is required between two gears meshing with each other, and the magnitude of the backlash may be caused by the occurrence of collision noise between teeth, the damage of gears, the operation delay and the like. In other words, the quality of the gear device is affected. for that reason,
Backlash is measured and adjusted to an appropriate size. This adjustment is performed by adjusting the distance between the axes of the shafts respectively supporting the two gears using a shim. By changing the thickness of the shim and changing the distance between the two axes, the magnitude of the backlash can be changed. Conventionally, a thick master shim is used to reduce the backlash by meshing the gears with each other. Measurement is performed, and based on the measurement result, a normal shim having a thickness capable of obtaining a proper backlash is selected. The backlash of a gear changes due to a manufacturing error or an assembly error of the gear. If the backlash is measured at each of a plurality of meshing positions of two gears meshing with each other, the backlash value at each position is usually different. The magnitudes of these backlash values and their variations are shown in FIG.
As shown in the example of FIG. However, the graph of FIG. 14 is based on the assumption that the backlash variation is caused by the eccentricity error of the gear and that the measurement error does not exist. Actually, the variation of the backlash is caused by factors other than the eccentricity error. The measurement value is not always as shown in FIG.

[0003] As described above, the backlash value differs for each gear, and also for one gear, differs depending on the meshing position. Therefore, the backlash is measured for a plurality of sets of gears of the same type, and the average of the backlash is determined for each gear. The normal shim was selected such that the average value was almost constant, as shown in FIG.
The backlash measurement value includes gear manufacturing errors, measurement errors, and the like. Even if these errors occur to the maximum in the direction in which the backlash decreases, the backlash value does not become negative for any of the multiple sets of gears. Error range (Fig. 1
5 shows in L ₁₎ Set is the normal shim thickness average value of the backlash of the gear is the value L ₁ was selected.

[0004]

However, if the normal shim is selected as described above, there is a problem that the backlash becomes considerably large even for a gear having a small variation in the backlash value. As shown in FIG. 15, when the variation is small gear backlash value, the range of error in the direction in which the backlash is reduced, the minimum of the slightly greater range L ₂ than the difference between the average value and the backlash measurements If set, the minimum backlash value does not become negative even if the error occurs to the maximum, whereas the range of the error is set according to the gear having a large variation in the backlash value, so the difference (L ₁ − Unnecessary backlash occurs only by L ₂ ), and a tooth collision sound, an operation delay, and the like occur. An object of the present invention is to provide a shim selecting method capable of suppressing the backlash of a gear having a small backlash variation.

[0005]

In order to solve this problem, a method of selecting a shim according to the invention of claim 1 of the present application is as follows.
(A) a step of measuring the magnitude of the backlash of the two gears at a plurality of meshing positions with the distance between the axes of the two gears adjusted by a master shim; and (b) a step of measuring the magnitude of the backlash. Determining a minimum backlash value from a plurality of backlash values, and selecting a normal shim in which the minimum backlash value is a predetermined constant value. Here, the “constant value” is a fixed value commonly defined for a plurality of sets of gears. The “backlash minimum value” is literally the minimum backlash value that is originally estimated based on a plurality of backlash values measured for a set of gears, but among the plurality of backlash values obtained by measurement, The smallest one may be regarded as the minimum backlash value and used. The invention of claim 2 is particularly advantageous in dynamic
The first shaft that rotates integrally with the first shaft that has an imbalance
The gear and the second shaft arranged in parallel with the first shaft rotate integrally.
A second gear rotatably provided and meshed with the first gear
Adjust the backlash with the method applied to select the shim
(C) the first shaft and the first gear are
Eccentric direction of the tooth surface of one gear and the dynamic unbalancing of the first shaft
Direction is opposite to the axis of the first axis.
(D) assembling into a state in which the first axis and the
The distance between the two axes is adjusted by the master shim.
To make the first gear and the second gear mesh with each other.
And (e) the first gear and the two gears
The magnitude of the backlash with the second gear is
A position corresponding to the eccentric direction of the tooth surface;
Including the position corresponding to the direction in which the
Measurement process to measure at each of the multiple locations
And (f) a plurality of bags obtained in the measurement process.
The minimum value of the lash values is a predetermined constant value.
A normal shim selecting step of selecting a normal shim to be performed.
Features.

[0006]

According to the first aspect of the present invention, if the normal shim is selected such that the minimum backlash value becomes a predetermined constant value, the range in which the backlash value of the gear varies varies as shown in FIG. The value is between the value and the value obtained by adding the magnitude of the variation of the backlash to the fixed value.The maximum value of the backlash is small for gears with small variation of backlash, and the maximum value of backlash is large for gears with large variation. . The backlash of each gear can be set without being affected by the variation of the backlash of the other gears. The constant value can be set to the value of the measuring device without considering the manufacturing error and assembly error of each gear. What is necessary is just to set in consideration of a measurement error. According to the second aspect of the present invention, the dynamic
The balanced first axis is driven by its dynamic imbalance.
Rotating in the bearing in the direction where centrifugal force acts.
In consideration of fluctuations in backlash caused by
The invention according to item 1 is implemented. The tooth surface of the first gear is eccentric
When the amount of eccentricity is large, the dynamic
If there is no balance, the part corresponding to the eccentric direction of the tooth surface
Backlash is minimized and the backlash on the opposite side is
Usually, the maximum is the maximum. Therefore, the invention of claim 2
In the light, the first shaft and the first gear are formed on the tooth surface of the first gear.
The dynamic imbalance between the eccentric direction of
Directions are opposite to each other with respect to the axis of the first axis.
Assembled. By doing so, the rotation of the first shaft
Occasionally, the first shaft is driven by the first gear in the bearing due to centrifugal force.
To rotate in a state deviated in the direction opposite to the eccentric direction
The effect of tooth eccentricity can be reduced more.
You. In carrying out the invention of claim 1,
Considering the fact that the "backlash minimum
Is set, the first axis and the second axis are actually
Backlash during shaft rotation is properly controlled
(As small as possible, but not too small)
The Rukoto.

[0007]

As described above, according to the shim selecting method according to the first aspect of the present invention , the backlash can be suppressed to a small value for a gear having a small variation in the backlash, and a good gear device having a small tooth collision noise or the like can be provided. Obtainable. Further, according to the shim selecting method of the invention according to claim 2,
If the first shaft has dynamic imbalance and the centrifugal force
The invention according to claim 1 when rotating in the direction of
The effect can be enjoyed favorably.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a gear device including a crankshaft and a balance shaft of an engine and gears provided on the engine.

In FIG. 2, reference numeral 10 denotes a crankshaft. The crankshaft 10 has four crankpins 1
The crank journal 14 includes two and five crank journals 14 and four sets of balance weights 16, and is rotatably supported by the blocks 18 on the crank journal 14. The block 18 has a schematic shape indicated by a two-dot chain line. A gear 20 is integrally attached to the crankshaft 10 and meshes with a gear 26 attached to the first balance shaft 24. The first balance shaft 24 is rotated about an axis parallel to the axis of the crankshaft 10 by a frame 28 (only a schematic shape is indicated by a two-dot chain line) mounted on the block 18 via a regular shim 27. Gear 26 is the gear 2 of the crankshaft 10 as shown in FIG.
In addition to 0, it is meshed with the gear 32 of the second balance shaft 30. The gear 26 and the gear 32 have different tooth widths,
The gear 32 is meshed with the gear 26 at a position shifted in the axial direction from the gear 20 of the crankshaft 10, and the gears 32 and 20 do not mesh with each other.

The first and second balance shafts 24,
The weights 33 and 35 are attached to 30 respectively. These first and second balance shafts 24, 30
Are for removing secondary vibrations generated during operation of the engine, and are rotatably supported by bearings attached to the frame 28 at their shaft portions. The tooth surfaces of the gears 20 and 32 are slightly deviated from the axes of the first and second balance shafts 24 and 30 due to manufacturing errors thereof, manufacturing errors of the first and second balance shafts 24 and 30, assembly errors, and the like. The weights 33 and 35 are attached to the shaft portions of the first and second balance shafts 24 and 30 at positions where the tooth surfaces are closest to the axis.

The crankshaft 10 functions as a first shaft having a gear 20 as a first gear, the first balance shaft 24 functions as a second shaft having a gear 26 as a second gear, and a block 18 and a frame 28. Constitutes a gear device main body 34, a crankshaft assembly 37 in which the crankshaft 10 is supported by the block 18, and a balance shaft assembly 38 in which the first and second balance shafts 24, 30 are supported by the frame 28. Are assembled via the normal shim 27 to form the gear device 36.

The assembly of the crankshaft assembly 37 and the balance shaft assembly 38 is performed by a dedicated assembly system. As shown in FIG. 4, this assembly system includes both assemblies 37 and 38.
And a first backlash measurement zone 40 for measuring the backlash of the gears 20 and 26 of the gear device 36 assembled using the master shim, and the two assemblies 3.
A normal shim assembling zone 42 in which the normal shims 27 and 38 are used instead of the master shims, and a second backlash measuring zone 44 for measuring the backlash of the gears 20 and 26 of the gear device 36 assembled with the normal shims. And First and second backlash measurement zones 40,
Each of the 44 has a backlash measuring device 46 and first and second data processing controllers 48 and 50 for performing data processing and controlling the backlash measuring device 46 based on the measurement result. These data processing controllers 48 and 50 are connected by a serial line 52 to transmit and receive data.

The backlash measuring device 46 will be described. The measuring device 46 includes a gear device 36 as shown in FIG.
A support table 54 is provided as a support device for supporting. The gear device 36 is transported by a transport device (not shown) in such a manner that the axes of the crankshaft 10 and the first balance shaft 24 are parallel to the transport direction (the left-right direction in FIG. 5), and is loaded onto the support 54. After being carried in, the support table 54 is raised, and the gear device 36 is positioned by the positioning jig and lifted from the transport device.

The measuring device 46 has an elevating table 56 which can be moved up and down on an apparatus main body (not shown). The elevating table 56 is configured to be moved up and down by an air cylinder (not shown), and a rotation drive device 58 and a fixing device 60 are attached to the lower surface thereof. The frame 62 of the rotary drive device 58 is slidably fitted to a pair of guide rails 64 (only one is shown in the figure) fixed to the lower surface of the lifting platform 56, and is driven by a drive cylinder 66. The crankshaft 1 moved in a direction parallel to the axis of the crankshaft 10 and supported by the support 54
It is approached and separated from 0. A rotation drive motor 68 is attached to the frame 62, and an engagement member 72 is attached to an output shaft of the frame 62 via an Oldham coupling 70 so that the engagement member 72 is engaged with one end of the crankshaft 10 so that it cannot rotate relatively. ing. The rotation drive motor 68 is an AC servomotor, and the rotation position is detected by the encoder 71. Further, the engagement between the engagement member 72 and the crankshaft 10 is detected by the detection device 73. Fixing device 6
The zero frame 74 is slidably fitted on a guide rail 76 fixed to the lower surface of the elevating table 56, and is moved in a direction parallel to the axis of the crankshaft 10 by a moving device (not shown). A clamper 78 is attached to the frame 74, and grips the other end of the crankshaft 10 so that it cannot rotate.

A moment applying device 80 and an angle detecting device 82 are provided at a portion between the rotary driving device 58 and the fixing device 60 of the elevating table 56. Hereinafter, these devices 80 and 82 will be described in detail with reference to FIGS. First, the moment applying device 80 will be described. As shown in FIG. 6, a rectangular opening 86 is formed in the elevating table 56, and a support plate 88 is fixed to the lower surface of the elevating table 56 to close the opening 86. This support plate 88 has four columns 9
0 are erected, and a mounting plate 92 is fixed to the ends of the columns 90. A holding cylinder 94 is fixed downward on the mounting plate 92, and its piston rod 9
6 penetrates through the mounting plate 92, and a pressing plate 98 is fixed to the protruding end so as to be relatively immovable in the axial direction, and is moved up and down by expansion and contraction of the piston rod 96. Two guide pins 100 are erected on the holding plate 98 and are slidably fitted in the mounting plate 92 in the axial direction to guide the holding plate 98 up and down. Also, the holding plate 9
8, holding bolts 102 are screwed downward at two positions of the gear device 36 supported by the support 54 and separated from each other in a direction parallel to the axis of the first balance shaft 24. A through hole 104 is formed in the mounting plate 92 at a position corresponding to the holding bolt 102, and the holding plate 98 is formed.
When the is lifted and lowered, the holding bolt 102 and the mounting plate 92 do not interfere with each other.

A pair of seats 110 are fixed to the support plate 88 concentrically with the pair of holding bolts 102. A through-hole 112 is formed in the seat 110 and penetrates in the vertical direction. The upper side of the through-hole 112 is a tapered hole 114 whose diameter increases upward. A rod 116 is fitted into each of the through holes 112 of the seat 110 with a gap in the radial direction. At the upper end of the rod 116, an engagement block 118 is attached.
8 has a tapered portion 120 corresponding to the tapered hole 114. A mounting plate 124 is fixed to lower ends of these rods 116, and three pressing members 126 (only two are shown in the figure) are fixed to the lower surface of the mounting plate 124, and the gear device 36 is fixed. The block 18 is pressed against the support table 54 by being in contact with the frame 28 of FIG. An engagement projection 128 is provided on the lower surface of the holding member 126 so as to bite into the frame 28 that supports the first and second balance shafts 24 and 30.

A lifting plate 130 is fitted to the rod 116 via a bearing 132 so as to be relatively movable in the axial direction. The lifting plate 130 is moved by a spring 136 disposed between the lifting plate 130 and a sleeve 134 fitted to the rod 116.
It is urged away from the mounting plate 124. A pair of engaging members 140 (only one is shown in the figure) are fixed to the lower surface of the portion between the pair of rods 116 of the lifting plate 130, and the lifting cylinder 144 fixed on the mounting plate 124. Piston rod 146 is engaged.
The engagement member 140 is formed by dividing a bottomed cylindrical member into two along a straight line, and is fixed to a protruding end of the piston rod 146 in a circular gap formed between the bottom and the elevating plate 130. The circular engagement plate 148 is fitted so as not to be able to come out leaving a gap in the axial direction, and the elevating plate 130 is moved up and down by expansion and contraction of the piston rod 146.
A contact block 152 is fixed on the elevating plate 130 so as to extend upward, and abuts on a pin 154 provided on the support plate 88 downward.

The first balance shaft 24 of the lifting plate 130
A support plate 158 is fixed to one of the two ends separated in a direction parallel to the axis of. As shown in FIG. 3, mounting plates 160 and 162 are fixed to both ends of the support plate 158 in a direction orthogonal to the axis, and two connecting rods 164 and 166 are respectively parallel to the axis. It is fixed in such a direction as to extend downward at a distance in a desired direction. These two connecting rods 164, 166
Are connected by connecting plates 168 and 170, respectively. These support plate 158, mounting plate 160, 1
62, connecting rods 164, 166 and connecting plate 168,
170 is moved up and down as the elevating plate 130 moves up and down,
An elevating member is constituted together with the elevating plate 130, and the elevating cylinder 144 constitutes an elevating drive device.

A rocking plate 174 as a rocking member is mounted on the connecting plates 168 and 170, and both ends thereof are extended to both sides from the axis of the first balance shaft 24 in plan view. ing. Connecting plates 168, 170
A conical positioning pin 176 is provided on each of the upper portions, and positioning holes 17 formed in the rocking plate 174 are provided.
8 to position the rocking plate 174. Further, conical positioning pins 182 are provided on the swinging plate 174 at both ends separated in the longitudinal direction.

At the center of the swing plate 174, the chuck 1
90 are attached. The chuck 190 has a pair of arms 192 rotatably mounted around an axis parallel to the axis of the first balance shaft 24, and a pair of links 19 at upper ends of the arms 192.
4, 196 are rotatably mounted, and the other ends of the links 194, 196 are rotatably connected. The chuck opening / closing cylinder 20 is provided on the swing plate 174.
0 is fixed upward, and a link 194 is attached to a block 204 engaged with the distal end of the piston rod 202.
The other end of the arm 196 is rotatably connected, and the arm 192 is rotated by expansion and contraction of the piston rod 202, and the gripping claw 20 attached to the lower end of the arm 192 is rotated.
6 is opened and closed to grip the first balance shaft 24,
release. The links 194 and 196 constitute a toggle mechanism, and the gripping pawl 206 is moved by the first balance shaft 24 by a relatively small operation of the chuck opening / closing cylinder 200.
Grip strongly.

Reference numeral 208 denotes an engagement pin protruding from the block 204, which is fitted into a through hole 212 provided in a regulating plate 210 fixed to the support plate 158. The engagement pin 208 has a cylindrical end at the proximal end and a tapered end at the distal end. When the chuck 190 does not grip the first balance shaft 24, the piston rod 202 is in the extended end position, The pin 208 fits into the through hole 212 to the base end to prevent the chuck 190 from rattling. When the chuck 190 grips the first balance shaft 24,
As the piston rod 202 is contracted, the tip of the engaging pin 208 is fitted into the through hole 212, and the gap between the engaging pin 208 and the through hole 212 allows the chuck 190 to swing.

Elevating cylinders 220 and 222 are fixed downward on the mounting plates 160 and 162, respectively, and weights 228 and 230 are relatively movable in the axial direction at the lower ends of the piston rods 224 and 226, respectively. Suspended. The weights 228 and 230 have the same configuration, and the weight 228 will be representatively described.

The weight 228 is connected to the first part 232 engaged with the piston rod 224 by a pin 234, and the second part 236 is positioned and mounted on the swing plate 174. Consisting of First part 23
2, a through hole 238 is formed to penetrate in the axial direction. The through-hole 238 has a stepped shape, and the small-diameter hole 2
A tapered hole portion 244 is formed between 40 and the large-diameter hole portion 242, and the piston rod 224 is fitted to the through hole 238 so as to be relatively movable in the axial direction, and is provided at the lower end thereof. The tapered portion 246 engages the tapered hole portion 244 and suspends the weight 228. Also, the second part 236
Is formed with a conical positioning hole 248 that is open on the lower surface thereof. These weights 228 and 230 are separated from the rocking plate 174 when the piston rods 224 and 226 are contracted, and the piston rods 224 and 226 are separated.
In a state of being suspended by the piston rod 2
If 24 and 226 are extended, positioning pins 182
And is positioned. Piston rods 224,2
If 26 is further extended from that state, the tapered portion 2
46 are separated from the tapered hole 244 by weights 228 and 23.
0 is supported by the rocking plate 174 via the positioning pin 182. Lifting cylinders 220, 22
2, the weights 228 and 230 constitute a load device.

Next, the angle detecting device 82 will be described.
The angle detecting device 82 includes, as shown in FIG.
The first balance shaft 24 is provided on the opposite side to the moment applying device 80 in a direction parallel to the axis of the first balance shaft 24. As shown in FIG. 8, the angle detecting device 82 includes a support plate 250 fixed to the elevating plate 130 and mounting plates 252 and 25 fixed to the support plate 250, similarly to the moment applying device 80.
4, two connecting rods 25 respectively attached to the mounting plates 252 and 254 so as to extend downward.
6,258 and connecting plates 260,262 connecting the lower ends of the connecting rods 256,258.
It has an elevating member that moves up and down together with the up and down movement of 30.

A rocking plate 264 is provided on the connecting plates 260 and 262.
And a chuck 270 is provided. The chuck 270 has a pair of arms 272 and a pair of links 274 and 276 similarly to the chuck 190 of the moment applying device 80. These links 27
4, 276 is rotatably connected to a block 282 engaged with a piston rod 280 of a chuck opening / closing cylinder 278 fixed on a swinging plate 264. Arm 272
Is rotated, and the gripping claws 284 respectively attached to the lower ends thereof are opened and closed, so that the first balance shaft 2 is rotated.
4. Grasp and release the other end of 4. An engagement pin 286 is provided upright on the block 282 and is fitted into a through hole 290 provided in a defining plate 288 fixed to the support plate 250 so as to prevent the chuck 270 from rattling. Have been.

As shown in FIG. 6, a detector 300 is provided upright at the portion of the swing plate 264 on the side of the lifting plate 130.
The detection body 300 extends upward from the rocking plate 264, and is bent toward the lifting plate 130 side.
Of the magnescale 3 at a position facing the detection body 300 in the direction orthogonal to the axis of the first balance shaft 24.
04 is attached. The tracing stylus 306 of the magnescale 304 is urged by urging means (not shown) and is brought into contact with the detection body 300, and moves following the detection body 300 when the swing plate 264 swings. The position of the detection object 300 is detected.

Next, measurement of backlash and normal shim 2
The selection of No. 7 will be described. First, in the master shim assembly zone 39, the crankshaft assembly 37
And the balance shaft assembly 38 are assembled using a master shim. This assembly is performed by an operator, and the crankshaft 10 and the first balance shaft 24
Are assembled such that the rotational phase of the engine becomes a phase for removing secondary vibration during operation of the engine. After the assembly, the gear device 36 is transported to the first backlash measurement zone 40 by a transport device (not shown), and the backlash is measured. This measurement was performed as shown in FIG.
Is performed at four engagement positions A, C, B, and D rotated by a set angle in one direction from the top dead center (hereinafter, referred to as measurement positions A, C, B, and D). For a multi-cylinder engine,
There are a plurality of crankpins 12, and the top dead center of the crankshaft 10 is the phase at which the piston of the engine cylinder is located at the top dead center for one of the crankpins 12. In this embodiment, four measurement positions A, C, B,
Among D, C is set at a position where the tooth surface of the gear 26 is closest to the axis of the first balance shaft 24, D is set at the farthest position, and A and B are set at positions intermediate between C and D.

The measurement of the backlash is performed as follows. At the time of non-measurement, the lift 56 is at the rising end position, and the rotary drive 58, the fixing device 60, and the moment applying device 8
The zero and angle detection device 82 is located above the support table 54, and the rotary drive device 58 and the fixing device 60 are respectively at the retracted end positions farthest from the support table 54. Further, the tapered portion 12 of the engagement block 118 of the rod 116
0 is engaged with the tapered hole 114, and the moment applying device 80
And an angle detecting device 82 are suspended from the elevating platform 56, and the chucks 190 and 270 of the devices 80 and 82 are suspended.
Is open.

Then, the gear device 36 is carried in, the support 54 is raised to a predetermined measurement position, and the gear device 36
Is positioned on the support 54, the lift 56 is lowered to the lower end. With the lowering of the elevating table 56, the holding member 126 is lowered, and the frame 2 of the gear device 36 is moved.
Contact 8 The elevating platform 56 is further lowered a small distance even after the pressing member 126 contacts the frame 28. This descent is allowed by the relative movement of the rod 116 and the elevating platform 56, and the elevating platform 56 is In a state where the rod is lowered to the lower end, the engagement block 118 is detached from the tapered hole 114, and the rod 116 is separated from the lift 56.

When the elevator 56 descends, the elevator 130 supported by the mounting plate 124 via the spring 136 also descends. Then, the pressing member 126
After the mounting plate 124 stops due to the contact of the mounting plate 124 with the frame 128, the pin 154 and the contact block 152 abut against the spring 136 while compressing the spring 136 and descending, regardless of the stop position of the mounting plate 124. Is lowered to a position determined based on the lowering end position of. During this time, the chuck 19 of the moment applying device 80 and the angle detecting device 82
When the lowering of the elevating plate 130 is stopped, the axes of the chucks 190 and 270 are slightly lower than the axis of the first balance shaft 24. become. Elevator 5
6, the holding plate 98 is lowered by the holding cylinder 94, and the holding bolts 102
Pushes the rod 116 downward, the engaging projection 128 projecting from the lower surface of the pressing member 126 is cut into the upper surface of the frame 28, and the frame 28 and the block 18 are pressed against the support table 54 by the pressing member 126. .

When the elevator 56 is lowered to the lower end, the axis of the engagement member 72 of the rotary drive device 58 and the fixing device 60 and the axis of the clamper 78 are further aligned with the crankshaft 1.
It becomes a state that almost coincides with the 0 axis. First, the piston rod of the drive cylinder 66 is connected to the crankshaft 1.
0, the engaging member 72 is engaged with one end of the crankshaft 10, and after the engagement state is confirmed by the detection device 73, the rotation drive motor 68 is rotated, and the crankshaft 10 and The first balance shaft 24 is rotated, and the gears 20 and 26 are rotated to the backlash measurement position A based on the rotation detection signal of the encoder 71. Since the engaging member 72 is attached to the rotation drive motor 68 via the Oldham coupling 70, even if the rotation axis of the rotation drive motor 68 and the axis of the crankshaft 10 are misaligned, the crankshaft 10 rotates without hindrance. Let me do. After the rotation, the clamper 78 is advanced to grip the other end of the crankshaft 10 and fix the crankshaft 10 at the backlash measurement position A.

As described above, when the lift 56 is lowered, the crankshaft 10 and the first balance shaft 24 are rotated to the backlash measurement position A, and the frame 28 and the block 18 are pressed by the pressing member 126, The chucks 190 and 270 are closed to grip both ends of the first balance shaft 24, respectively. As described above, since the axes of the chucks 190 and 270 are slightly lower than the axis of the first balance shaft 24, when the chucks 190 and 270 are closed, they rise slightly, and the swing plates 174 and 264 are moved. Are slightly lifted from the connecting plates 168, 170, 260, 262, respectively. However, the rocking plates 174 and 264 to which the chucks 190 and 270 are attached are generally slightly inclined, and one of both ends in the longitudinal direction is connected to the connecting plate 168 or 170 and the connecting plate 260 or 26, respectively.
2 is supported. Then, from this state, the elevating plate 130 is lowered by the elevating cylinder 144, and the connecting plates 168, 170, 260, 262 are lowered, so that the rocking plates 174, 264 are in a state where they can be rocked by a sufficient angle. At the same time, rocking plates 174, 264 and chucks 19 are provided at both ends of the first balance shaft 24, respectively.
0, 270, the weights of the chuck opening / closing cylinders 200, 278, etc. are added downward.

Next, of the two weights 228 and 230, first, the weight 228 is lowered and the rocking plate 174 is moved.
7 and a clockwise rotational moment in FIG. 7 is applied to the first balance shaft 24. As a result, if the first balance shaft 24 rotates in the same direction,
The swing plate 264 attached to the other end of the first balance shaft 24 swings, and the detector 300 swings,
The position is measured by the magnescale 304.
After this measurement, the weight 228 is raised,
The other weight 230 is lowered and supported by the swing plate 264, and a counterclockwise rotational moment is applied to the first balance shaft 24. In this case, the swing plate 26
4 oscillates in the opposite direction, and the position of the detector 300 at that time is measured by the magnescale 304. Thus, when the rotational moment in both the forward and reverse directions is applied to the first balance shaft 24, the detector 300 Backlash is calculated based on the change in position.

The backlash BL is the portion shown in FIG. 9 and is represented by the following equation (1).

(Equation 1) However, MGSD: the position of the detection body 300 when the teeth come into contact with each other when the forward rotation moment is applied to the first balance shaft 24, and the teeth when the reverse rotation moment is applied. B: distance between the pitch of the gear 26 and the center of the measuring element 306 of the magnescale 304. If the rotation angle when the balance shaft 24 rotates by the backlash BL is θ, the backlash BL becomes B
L = (B / 2) · θ, distance MGSD is MGSD = LAR
M · θ, and the above equation is obtained from these equations. B
And LARM are known values, and M
GSD is a value obtained by measuring the magnescale 304, and the backlash BL can be obtained from B, LARM, and MGSD.

When the backlash BL is measured in this way, the lifting plate 130 is raised and the swing plate 17
The swingable angles of 4,264 are connected plates 168,1 respectively.
After being limited by 70, 260, 262, the gripping of the first balance shaft 24 by the chucks 190, 270 is released, and the swing plates 174, 264 are connected to the connecting plate 168,
170, 260, 262 and the like. In this state, the crankshaft 1
0 is released, the crankshaft 10 and the first balance shaft 24 are rotated, the gears 20 and 26 are rotated to the next backlash measurement position C, and the backlash is measured again.

When the backlash has been measured at all of the measurement positions A, B, C, and D, the measured values are sent to the first data processing controller 48, and the normal shim 27 is selected. The actual backlash measurement shows a gear 26
Not only the eccentricity error, but also other manufacturing errors and assembly errors, and backlash measurement errors are included, but in general,
The larger the amount of eccentricity, the larger the difference between the backlash values at the measurement points A, B and C, D. Therefore, in the assembling system of this embodiment, it is determined whether the eccentricity is large or small depending on whether the difference is 5 or more, and the method of selecting the shim can be changed.

The first data processing controller 48 first determines whether the eccentricity of the gear 26 is large. Assuming that the backlash values obtained at the measurement positions A, C, B, and D are 100, 110, 100, and 90, respectively, the difference between the backlash values at the measurement positions A and B and C and D is 5 or more. And the amount of eccentricity is large. Therefore, shim selection when the amount of eccentricity is large is performed.

The selection of the normal shim will be described with reference to FIG. Backlash BL of gears 20 and 26 when crankshaft assembly 37 and balance shaft assembly 38 are assembled using a master shim
Is B.MGSD / 2.LARM, but the master shim is set to be thick and the backlash is large, and the backlash amount SHBL to be reduced when assembling using the normal shim 27 is expressed by equation (2).

(Equation 2) However, BLP: the minimum value among the backlash values of the measurement positions A, C, B, and D BLO: the target backlash value BLS: the target value of the backlash BLSH: the backlash measurement amount when assembled using the normal shim 27 Change (amount of shift of target value) BLiN: Line correction amount

The target backlash value BLO is determined for the minimum value of the four measured values, and the difference is obtained. The target backlash value BLO is obtained by correcting the target value BLS of the backlash with the correction values BLSH and BLin. Desired. The target value BLS of the backlash is set based on the measurement error of the measuring device 46. Measuring device 46
Can be determined in advance, and here ± 25
Let μ. And the backlash target value BLS
Is set to such a value that the minimum backlash value when the gears 20 and 26 are not rotating is −5 μ even when the measurement error occurs to the maximum.

As described above, the first balance shaft 24
Weight 33 is attached at a position where the tooth surface of the gear 26 is closest to the axis of the first balance shaft 24,
The bearing that supports the first balance shaft 24 is a slide bearing, and there is a radial gap between the first balance shaft 24 and the bearing. Therefore, when the crankshaft 10 and the first balance shaft 24 are rotated while meshing with each other, the first balance shaft 24 moves in the bearing in the direction in which the centrifugal force of the weight 33 acts, and the teeth of the gear 26 The surface is the first balance shaft 24
The first balance shaft 24 moves in the bearing in the direction closest to the crankshaft 10 at the position where the backlash is supposed to be the maximum and the backlash is small, and the backlash is reduced.

Conversely, at a position where the tooth surface of the gear 26 is farthest from the axis of the first balance shaft 24 and the backlash is to be minimized, the first balance shaft 24 is cranked in the bearing by the centrifugal force generated by the weight 33. It moves away from the shaft 10 and the backlash increases. Therefore, even if the backlash at the meshing position where the backlash is minimized is set to be negative during non-rotation, it can be prevented from actually becoming negative during rotation.

In particular, when the amount of eccentricity of the gear is large, the position where the tooth surface is farthest from the axis can be clearly recognized even in the presence of a measurement error, and the backlash at the position where the backlash is maximum is considerable. Vibration and noise increase as the size increases, and it is highly necessary to reduce backlash. Therefore, when the amount of eccentricity of the gear is large, the target value BLS of the backlash is set to 20 μ with respect to the measurement error ± 25 μ, whereby the maximum error occurs as shown by the solid line in FIG. , The minimum backlash value becomes −5 μm, but actually becomes +5 μm due to the movement of the first balance shaft 24 in the bearing due to the centrifugal force of the weight 33.

The distance SHD between the axes of the crankshaft 10 and the first balance shaft 24, which should be reduced in order to achieve the target backlash value BLO, is expressed by the following equation (3).

(Equation 3) Where k: backlash constant

The crankshaft 10 and the first balance shaft 24 when assembled using a master shim
The distance DIS between the respective axes is expressed by equation (4).

(Equation 4) Where P _{0 is} the vertical distance between the axes of the crankshaft 10 and the first balance shaft 24 when assembled using the master shim. Q: The crankshaft 10 and the first balance shaft 24.
Horizontal distance of each axis with

Further, the crankshaft 10 and the first balance shaft 2 when assembled using the regular shim 27
The vertical distance P between each axis and the axis 4 is expressed by equation (5).

(Equation 5) Then, the optimum thickness T of the normal shim 27 is obtained by Expression (6).

(Equation 6) However, TMS: thickness of the master shim The shim number No of the normal shim 27 is obtained by the equation (7) based on the thickness T of the normal shim 27.

(Equation 7) Where T _{0 is the} minimum shim thickness Tcs is the shim thickness correction value fed back from the second data processing controller 50 DT: the shim thickness corresponding to the one-step shim number If the calculated shim number value includes a value below the decimal point, it is rounded off to an integer value.

The first data processing controller 48 selects the normal shim 27 as described above, and uses the selected normal shim 27 to assemble the gear 20, 20 when the crankshaft assembly 37 and the balance shaft assembly 38 are assembled. The estimated value of the backlash 26 is calculated, and the selected number of the normal shim 27 and the estimated value of the backlash are transmitted to the second data processing controller 50 in the second backlash measurement zone 44.

Next, the gear device 36 is sent to the normal shim assembling zone 42, where the master shim is removed and assembled using the normal shim 27. After assembling, the gear device 36 is sent to the second backlash measuring zone 44, where the backlash is removed. Measured. This measurement is also similar to the measurement of backlash when assembled using a master shim.
Are performed at four measurement positions A to D rotated by a set angle in one direction from the top dead center. Measured backlash when assembling with master shim and normal shim 27
FIG. 12 shows the relationship between the predicted value of the backlash and the actually measured value in the case of assembling using. The measured value is sent from the backlash measuring device 46 to the second data processing controller 50, and it is determined whether the measured value and the predicted value sent from the first data processing controller 48 are within an error range (± 25μ). Is done.

If the difference between the measured value and the predicted value is within the range of the error, it is determined that the selection of the normal shim 27 is appropriate, but if the difference is out of the range, the selection of the normal shim 27 is incorrect. It is conceivable that some abnormality has occurred, for example, there is a deviation, or the zero point of the backlash measurement device 46 in the first backlash measurement zone 40 is shifted. Also, 4
If the measured values are within the range of the error, but are relatively large, it is possible to further reduce the backlash by further reducing the thickness of the normal shim 27. Therefore, the correction value Tcs is calculated to change the thickness of the normal shim 27 based on the deviation between the measured value and the predicted value and the magnitude of the backlash variation, and the first data processing controller 4
8 is fed back. As a result, when measuring the backlash of the gears 20 and 26 of the gear device 36 in which the next normal shim 27 is selected, the selected normal shim changes.
The backlash value is set to a smaller value.

The correction value Tcs is calculated to obtain the normal shim 2
If the deviation between the measured value and the predicted value is not corrected by changing the thickness of the first and second backlash measurement zones 4,
This means that a situation that cannot be solved by the change in the selection of the normal shim 27, such as an abnormality of the backlash measuring device 46 at 0, 44, occurs. In this case, the first data processing controller 48 sets some reference (for example, The correction value Tcs may be changed continuously) to detect the abnormality and notify the operator.

The selection of the normal shim 27 when the amount of eccentricity of the gear 26 is large has been described above.
When the difference between the measured values of C and D is smaller than 5 and the amount of eccentricity of the gear 26 is small, the target value BLS of the backlash is such that the minimum backlash value is not negative even when the motor is not rotating (measurement error is ± In the case of 25μ, it is set to 30μ). When the amount of eccentricity is small, if the backlash value on the side opposite to the position where the weight 33 is attached is set to be negative, the movement of the first balance shaft 24 makes the backlash value at that position actually negative. Never
The backlash value at the position where the weight 33 is attached is equal to the crankshaft 10 of the first balance shaft 24.
This is because there is a possibility that the gear may be actually damaged by the movement to the side and the gear may be damaged. When the amount of eccentricity is small, it is difficult to clearly know the position where the tooth surface of the gear 26 is farthest from the axis of the first balance shaft 24, and the gear 26
This is because the backlash can be reduced at all the rotational positions of, and furthermore, it is not necessary to forcibly reduce the backlash.

As described above, according to the shim selection method of this embodiment, the minimum value of the backlash values obtained at a plurality of measurement points is set to a constant value (20 μ or 30 μ) set based on the measurement error. To be a regular shim 2
7 is selected. Therefore, the backlash is not unnecessarily increased for gears with small variations, and the gear device 36 with less vibration and noise can be obtained.
Conventionally, as shown by a two-dot chain line in FIG. 1, an error range is set to ± 40 μ including a gear manufacturing error, a measurement error, and a backlash measurement position error so that the minimum backlash value does not become negative. Since the regular shim is selected, the backlash becomes large even for a gear having a small backlash variation, but the backlash can be suppressed to a very small value.

Further, in this embodiment, the measurement positions of the backlash are set at four specific positions in consideration of the mounting position of the weight 33, and the case where the back shim is assembled using the master shim and the case where the back shim is assembled using the regular shim 27 are described. In this case, no error occurs due to the difference in the measurement position, and it is not necessary to consider this error when selecting the normal shim, and the backlash can be reduced.

Further, in this embodiment, the weight 3
3 is mounted so that the tooth surface of the gear 26 is closest to the axis of the first balance shaft 24, and the centrifugal force generated by the weight 33 causes the gear 26 to move away from the gear 20 at the position where the tooth surface of the gear 26 is farthest from the axis. In addition, the normal shim is selected so that the minimum backlash value becomes negative, and accordingly, the maximum value of the backlash is suppressed small, and the gear device 36 with less noise is obtained.

Further, in the present embodiment, the expected value of the backlash obtained when assembling using the normal shim 27 is compared with the measured value, and the correction value Tcs for selecting the normal shim 27 is calculated. Feedback is provided, and a normal shim that can further reduce backlash can be selected.

Although the embodiment of the present invention has been described in detail above, this is merely an example, and various modifications and improvements have been made based on the knowledge of those skilled in the art without departing from the scope of the claims. The invention can be implemented in embodiments.

[Brief description of the drawings]

FIG. 1 shows a backlash measured using a normal shim selected by a shim selection method according to an embodiment of the present invention;
5 is a graph illustrating backlash measured using a shim selected by a conventional selection method.

FIG. 2 is a front view schematically showing a gear device in which a normal shim is selected by the shim selecting method according to the embodiment of the present invention.

FIG. 3 is a side view schematically showing the gear device.

FIG. 4 is a diagram schematically showing a shim assembling system in which the shim selecting method is performed.

FIG. 5 is a front view showing a backlash measuring device provided in the shim assembling system.

FIG. 6 is an enlarged front view showing a main part of the backlash measuring device.

FIG. 7 is a front view (partial cross section) showing a moment applying device of the backlash measuring device.

FIG. 8 is a front view showing an angle detection device of the backlash measurement device.

FIG. 9 is a diagram illustrating calculation of backlash by the backlash measurement device.

FIG. 10 is a diagram illustrating selection of a normal shim according to the shim selection method.

FIG. 11 is a diagram showing a backlash measurement position by the backlash measurement device.

FIG. 12 is a diagram showing a relationship between a backlash value when the gear device is configured using a master shim and a predicted value and an actually measured value of the backlash value when the gear device is configured using a normal shim in the shim selecting method. is there.

FIG. 13 is a graph for explaining the effect of the present invention.

FIG. 14 is a graph showing the backlash obtained for each of a plurality of gears.

FIG. 15 is a diagram illustrating a conventional shim selection method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Crankshaft 20 Gear 24 First balance shaft 26 Gear 27 Regular shim 36 Gear device 46 Backlash measuring device

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ryoji Mizutani 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Katsuya Narisawa 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation ( 72) Inventor Tadashi Kumazawa 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) References JP-A-55-72939 (JP, A) JP-A-54-1530 (JP, A) 4-232395 (JP, A) JP-A-62-62058 (JP, A) JP-A-51-13056 (JP, A) JP-A-2-221839 (JP, A) JP-A-1-165929 (JP, A A) JP-A-63-180767 (JP, A) JP-A-3-163327 (JP, A) JP-A-63-23044 (JP, A) JP-A-2-217646 (JP, A) JP-A-60 -109638 (JP, A) Actually open 64-64758 (JP U) JitsuHiraku flat 1-136756 (JP, U) JitsuHiraku Akira 55-137737 (JP, U) (58 ) investigated the field (Int.Cl. ^7, DB name) F16H 57/12 F16F 15/26

Claims (2)

(57) [Claims] 1. A method of selecting a shim for adjusting the backlash of two gears meshing with each other, wherein the distance between the axes of the two gears is adjusted by a master shim. A measurement step of measuring the size at a plurality of meshing positions; obtaining a minimum backlash value from a plurality of backlash values measured in the measurement step; and selecting a normal shim in which the minimum backlash value is a predetermined constant value. A backlash adjusting shim selecting method, comprising a normal shim selecting step. 2. Integrated with a first shaft having dynamic imbalance
A first gear that rotates in a rotational direction, and a first gear that is disposed in parallel with the first shaft.
Provided so as to be able to rotate integrally with the two shafts and mesh with the first gear
Select the shim to adjust the backlash with the second gear
Is a method of choosing The first shaft and the first gear are eccentric to the tooth surface of the first gear;
Direction in which the dynamic imbalance between the direction and the first axis is the largest
Are set so that they are opposite to each other with respect to the axis of the first axis.
The process of standing up, The first axis and the second axis have a distance between the axes.
The first gear and the second tooth are adjusted by a master shim.
A step of making the vehicle mesh with the vehicle; With the two gears engaged with each other, the first gear and the second gear
The magnitude of the backlash is determined by the eccentricity of the tooth surface of the first gear.
Position corresponding to the direction and the dynamic imbalance
A plurality of predetermined positions including a position corresponding to a certain direction
At each position, a measuring step for measuring, Of multiple backlash values obtained in the measurement process
A normal shim whose minimum value is a predetermined constant value
A normal shim selecting step of selecting.
How to select shims for adjusting the crash.