JPS5817328A - Device for measuring torque in transmission gear box - Google Patents

Abstract

PURPOSE:To detect the torque by a simple constitution and to omit a slip ring, by forming a thin part at the outer surface of a bearing housing, and measuring the torque by strain in the axial direction of the thin part. CONSTITUTION:The thin part 10c is formed around the entire outer surface of the housing 10 for the bearing 4. A strain measuring gage which detects the strain in the axial direction of the thin part 10c is attached to the thin part 10c. The thrust due to the engagement of gears is generated in the housing 10 which supports a tapered roller bearing 4, and the elongation in the axial direction is yielded in the thin part 10c. The torque is measured by measuring said elongation by the strain gate.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a torque detection device that detects torque when rotational power is transmitted through a transmission gear box.

Conventionally, when measuring torque (of rotational power),
Generally, a strain gauge is attached to the rotating shaft obliquely with respect to the axial direction, and the torque is measured by detecting the twist of the rotating shaft using the strain gauge. Although this conventional method is effective, since it detects from the rotating shaft, that is, the rotating part, it requires a slip ring, and if it is complicated, it has disadvantages such as a shortened service life due to wear of the slip ring.

This invention was proposed under the above circumstances, and an object of the present invention is to obtain a torque measuring device that can detect torque from a fixed part that does not rotate, and therefore can detect torque with a simple configuration. It is something.

Embodiments of the present invention will be described below with reference to the drawings.

1/The figure shows the cross section of a helical gear with reduced continuation -e - 1 is the input shaft, 2 is the helical gear fixedly running on the input shaft IK, δ is the input shaft l
This is a cylindrical roller bearing that supports one side of the shaft, but does not support thrust. The number is a conical roller bearing that supports the input shaft 1 and also supports the thrust. b is a gear that meshes with the helical gear 2; 6 is an output shaft that fixes the helical gear 6; and 7 is a conical cup that supports one side of the output shaft 6.
With bearings, this also supports the thrust. A cylindrical roller bearing 8 supports the other side of the output shaft 6, and does not support thrust. 9 is a deceleration nurse, that is, a gearbox.

Part A of FIG. 1 is shown in a second enlarged form.

Reference numeral 10 denotes a housing for accommodating and holding the conical stiff bearing metal, which extends from the flange portion 10g and the cylindrical portion 10b. This housing 10 has a flange portion 101 with a
1 is fixed to the gear box 9', and on the outer periphery of the cylindrical portion 10b there is a thin-walled portion 10 having an equal thickness over the entire circumference and a wide width.
c is made into yfl.

The outer ring 4a of the conical roller bearing 4 is fitted into the housing 1o and is held by a step Nod formed at the end of the housing 10 and a cover 18 fixed to the flange [10] of the housing 10 with bolts 12, The inner ring 4b is fixed to the human power shaft 1 by a stepped portion 1m formed at the end TIC of the input shaft 1, and by a lug 14 that is screwed into the end of the input shaft 1.

Further, an annular reinforcing member 16 is fitted into the cylindrical portion 10bK of the housing 10, and this reinforcing member 15 is fixed to the seventh flange 1ffilo- of the housing 10 with bolts 16. Note that this reinforcing member 15 has a thin wall portion 10C.
The thin wall part 1 supports the radial bending moment applied to the
0C, and includes a stepped portion 10e with a protruding outer circumference Vci of the cylindrical portion of the housing 10, and an In! A slight gap TIc is provided between the strong member 15 and the stepped portion 15a provided on the inner periphery so as not to restrict the extension of the cylindrical portion 10b of the housing 10 in the axial direction.

As shown in FIG. 3, a measuring strain gauge 17 for measuring the strain in the longitudinal direction of the input shaft of the housing 10 is attached to the thin wall portion 10c along the longitudinal direction of the input shaft, and temperature compensation is performed to eliminate temperature errors. The strain gauge 18 is attached in a direction perpendicular to the axial direction. The pair of strain gauges 17 and 18 are pasted, for example, at two points facing each other on the circumference, forming a Wheatstone bridge circuit lIc41iil as shown in Figure #13, and inputting it to a strain meter (not shown).

Next, the effect will be explained.

When the rotational power in the direction of arrow 0) in the first (b) of the human power mlK is input, the rotational power is transmitted to the output shaft 6 due to the meshing of the helical gear 2 and the helical gear, but due to the meshing of the helical gear Since a thrust is generated, the housing 10 holding the conical four-shaft bearing number receives a tensile force in the direction of the arrow (b) in FIG. This elongation strain is detected by the measurement strain gauge 17, corrected by the temperature compensation strain gauge 18, and input into the strain meter to be measured as strain.

Now, let the transmission torque generated on the input shaft l be T1, the reference pitch radius of the helical gear 2, and the angle that the spiral teeth of the helical gear 2 make with the axis 11 be the reference pitch circle of the helical gear 2 teeth. The transmitted force acting in the am direction is F3, and the thrust in the axial direction generated at that time is F! Then, F@
The relationship of @F @TI is as shown in Figure S, and the following relationship holds true for T-RXF.

F, = xp, -θ = T ta I / FL.

Transforming this, 'r==R,xF', /lnl =-=-(11
That is, the torque T is calculated based on the equation (1)/C from the thrust F and 'Ic.

, , is F,= based on the cross-sectional area A of the thin part 10C, the % Young's modulus E, and the measured strain signature.
AEg...--(2) Measured.

Note that the torque T can be immediately measured from the strain gvc of the thin wall portion 10c of the housing 10 by using the circuit that calculates the formula (1>, (fi3) above.

It should be noted that the gears that generate thrust include the hasp gear VC@ of this embodiment, the hasp bevel gear, screw gear, and worm, and the housing geter that holds the bearing of the shaft of these gears is attached with a strain gauge as described above. Torque can be measured by attaching it.

In addition, as a bearing that supports a shaft where thrust is occurring,
In addition to the conical roller bearing of this embodiment, a spherical roller bearing may also be used, or a bearing receiving only radial force and a thrust bearing receiving only thrust force may be provided separately. In this case, attach a strain gauge to the thrust bearing housing.

As described above, the transmission steel car box thrust measuring device of the present invention forms a thin walled part all around the outside of the housing of the bearing where the thrust acts, and the shaft of the thin walled part A strain gauge that detects strain in the longitudinal direction is attached, and the torque is measured by the strain in the longitudinal direction of this thin section, which is different from the conventional method of detecting torque by attaching a strain gauge to the rotating shaft. The torque can be detected with an extremely simple configuration without the complexity of using a slip ring, and the life of the slip ring will not be shortened due to wear.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is an enlarged detailed view of part A in FIG. 1, FIG. 3 is a side view showing only the bearing housing, and FIG. figure,
FIG. S is an explanatory diagram of the magnitude of thrust. l...Input shaft, 2...Haspa south car, 8
... Cylindrical roller bearing, 4 ... Conical roller bearing, 9 ... Reduction lever case (m car box), 10 ...
...Housing, 10c...Thin wall part, 18
...Cover, 15...Reinforcement member, 17
・・・・・・Strain gauge for metering. Applicant Niigata Iron Works Co., Ltd.

Claims (1)

[Claims] In a pair of meshed gear devices, one shaft is supported by a bearing that can support the thrust generated during driving, and the outer periphery of the housing that holds this bearing and is fixed to the gear box is electrically plated all around. 1. A transmission gear box torque measuring device, characterized in that a thin walled portion having a certain thickness and an equal width is formed, and a strain gauge is attached to the thin walled portion to detect strain in the axial direction of the thin walled portion.