CN117309219A - Tractor saddle six-direction force testing device and calculation method - Google Patents

Abstract

The invention belongs to the technical field of vehicle testing, and specifically provides a six-way force testing device and a calculation method for a tractor saddle. The device includes a base plate and a traction pin adapter. The base plate is fixed on the tractor frame and is connected to the trailer through the traction pin adapter. The traction pin realizes the connection between the tractor and the trailer; the three-way force between the traction pin adapter and the base plate is obtained through four three-way force sensors distributed between the base plate and the traction pin adapter, and the relative force between the three-way force sensor and the traction pin adapter is combined The positional relationship establishes a saddle load six-way force solution matrix, and then obtains the real-time dynamic three-way force and three-way moment transmitted by the saddle, providing accurate load input for vehicle product development, and effectively improving the vehicle's power, economy, and ride comfort. , Structural fatigue performance; the positional relationship of the four three-way force sensors relative to the center of the traction pin can change with structural changes, increasing the convenience and practicality of sensor arrangement.

Description

A six-directional force testing device and calculation method for a tractor saddle

Technical field

The invention relates to the technical field of vehicle testing, and in particular to a tractor saddle six-way force testing device and a calculation method.

Background technique

When the tractor and the trailer are connected, the tractor and the trailer are connected by connecting the trailer traction pin through the traction pin adapter. During the actual driving process, the tractor and the trailer transmit the X/Y/Z three-way load through the saddle. During braking and starting When turning, turning and passing through potholes, the load is relatively severe, which has a great impact on the strength of the saddle and connecting parts.

The saddle is a key component of the semi-trailer tractor to realize the vehicle traction function. It is installed on the frame through bolt connection to realize the load transfer between the semi-trailer tractor and the trailer. The load transmitted at the saddle is directly related to the vehicle's power, economy, ride comfort, and structural fatigue performance. Therefore, accurate measurement of the saddle's three-way force and three-way moment is critical to vehicle performance development.

At present, during the vehicle load test, the detection device that measures the force on the traction pin of the semi-trailer can only measure the Z-direction force at the saddle. The sensitivity is not high, and there is a lag in the process, which reduces the measurement accuracy.

Contents of the invention

In response to the above problems, the purpose of the present invention is to provide a six-way force testing device for a tractor saddle. The device includes a force measuring component. The force measuring component is installed on the tractor frame through the bottom plate and is connected to the trailer traction pin through a traction pin adapter. , to realize the connection between the tractor and the trailer, the three-way force at different positions between the traction pin adapter and the base plate is obtained through the four three-way force sensors distributed between the base plate and the traction pin adapter, and the three-way force sensor and the center of the traction pin adapter are combined The relative position relationship is calculated to obtain the three-way force and three-way moment transmitted by the saddle, which provides accurate load input for vehicle product development and effectively improves the vehicle's power, economy, ride comfort, and structural fatigue performance.

The technical solution of the present invention provides a six-directional force measuring device for a tractor saddle, which includes a base plate and a traction pin adapter; both ends of the base plate are connected to the traction pin adapter through a load-bearing beam respectively;

A three-way force sensor is set between the two ends of each load-bearing beam and the bottom plate to obtain the force at different positions between the traction pin adapter and the bottom plate.

As a preferred technical solution of the present invention, a sensor force-measuring hole is provided on the bottom plate, and there are sensor mounting holes at both ends of the load-bearing beam. During installation, the sensor force-measuring hole and the sensor mounting hole are on the same central axis, and the connecting bolts pass through the sensor mounting holes and the sensor mounting holes in sequence. The three-way force sensor is connected to the preload nut. After installation, the preload nut is in the sensor installation hole.

As the preferred technical solution of the present invention, the three-way force sensor includes a core shaft and a connecting frame member; the core shaft is connected to the connecting frame member through a sensitive beam;

Strain gauges are arranged on the sensitive beams.

As a preferred technical solution of the present invention, the base plate is provided with a fixing hole for fixing the three-way force sensor on the base plate;

A through hole is provided in the middle of the core shaft. During installation, the connecting bolts pass through the sensor installation hole in sequence and the through hole of the three-way force sensor core shaft is connected to the preload nut.

As a preferred technical solution of the present invention, the load-bearing beam is connected to the traction pin adapter through a rubber bearing.

As a preferred technical solution of the present invention, the rubber bearing includes a bearing pressure plate, a bearing bracket and a bearing bushing;

The bearing bushing is set on the bearing bracket;

The load-bearing beam is provided with a mounting groove, a bearing bracket mounting hole is set in the mounting groove, the bearing pressure plate is set in the installation groove, the bearing bracket is set on the upper end of the bearing pressure plate and is connected to the load-bearing beam through the bearing bracket mounting hole;

Both ends of the bearing pressure plate are provided with connection and fixing holes, and the bearing pressure plate is connected to the traction pin adapter through the connection and fixation holes.

As a preferred technical solution of the present invention, the number of three-way force sensors is four, and the four three-way force sensors are realized by arranging four sensitive beams.

As the preferred technical solution of the present invention, four three-way force sensors use Wheatstone bridges to obtain the forces in the three directions of X/Y/Z at the location.

As the preferred technical solution of the present invention, a unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the X-direction, a total of four strain gauges, forming a Wheatstone full bridge for measuring the X-direction force;

One unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the Y direction. A total of four strain gauges form a Wheatstone full bridge for measuring the Y direction force;

A unidirectional strain gauge is arranged on the surface of the four sensitive beams, a total of eight strain gauges, forming a Wheatstone full bridge for measuring Z-direction force.

The force measuring components include a base plate, four three-way force sensors, four connecting bolts, four preload nuts, two load-bearing beams, two rubber bearings, two rubber bearing brackets, two rubber bearing pressure plates, traction pin adapters and Other fixing bolts; the bottom plate is punched and cut from a whole steel plate. There are bolt holes on both sides of the bottom plate for connection with the frame. There are sensor force measuring holes at the four corners of the bottom plate; the load-bearing beam There are sensor mounting holes at both ends, and there are rubber bearing bracket mounting holes and bolt holes in the middle; the base plate and the three-way force sensor are connected by bolts; the three-way force sensor and the load-bearing beam are connected by bolts; the load-bearing beam and the traction beam are connected by bolts. The pin adapter is connected through a rubber bearing; the rubber bearing is composed of a rubber bearing bracket, a rubber lining, and a rubber bearing pressure plate; the rubber bearing, the traction pin adapter, and the rubber pressure plate are connected through bolts, and the rubber bearing and the load-bearing beam are connected through the rubber bearing bracket and the load-bearing beam; The four three-way force sensors can respectively obtain the X/Y/Z three-way force at the location; the three-way force sensors are distributed in an array on the bottom plate. When the traction pin adapter is subjected to forces and moments from the traction pin, the forces and moments are transmitted to the four three-way force sensors through the rubber bearing and the load-bearing beam. By decoupling the forces on the four sensors, the force and torque transmitted by the traction pin are calculated. Forces and moments.

The technical solution of the present invention also provides a force measurement calculation method based on the device described in the first aspect, which includes the following steps:

Obtain the X/Y/Z-direction force collected by each three-way force sensor respectively and calculate the X/Y/Z-direction force at the center of the saddle based on the obtained force;

Obtain the distance in the X/Y direction from the center of each three-way force sensor to the center of the bottom plate respectively;

Based on the calculated X/Y/Z force at the center of the saddle and the obtained distance, the moments around the X/Y/Z direction at the center of the saddle are calculated respectively. The base plate can be identified as four independent zones, and the four three-way force sensors in their respective zones can be reasonably adjusted to the relative position of the saddle center as the structure changes.

It can be seen from the above technical solution that the present invention has the following advantages: the three-way force at different positions between the traction pin adapter and the base plate is acquired through four three-way force sensors distributed between the base plate and the traction pin adapter, and the three-way force sensor is combined with the The relative position relationship of the traction pin adapter establishes the saddle load six-way force solution matrix, and then obtains the real-time dynamic three-way force and three-way moment transmitted by the saddle, providing accurate load input for vehicle product development, effectively improving the vehicle's power and Economy, ride comfort, and structural fatigue performance; the positional relationship of the four three-way force sensors relative to the center of the traction pin can change with structural changes, increasing the convenience and practicality of sensor arrangement.

In addition, the design principle of the invention is reliable, the structure is simple, and it has very broad application prospects.

It can be seen that compared with the prior art, the present invention has outstanding substantive features and significant progress, and the beneficial effects of its implementation are also obvious.

Description of the drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those of ordinary skill in the art, It is said that other drawings can also be obtained based on these drawings without exerting creative work.

Figure 1 is a perspective view provided by an embodiment of the present invention.

Figure 2 is an exploded view provided by an embodiment of the present invention.

Figure 3 is a diagram of the structure and strain gauge arrangement of the three-way force sensor of the present invention.

Figure 4 is a Wheatstone bridge diagram of the X-direction force of the three-direction force sensor of the present invention.

Figure 5 is a Wheatstone bridge diagram of the Y-direction force of the three-direction force sensor of the present invention.

Figure 6 is a Wheatstone bridge diagram of the Z-direction force of the three-direction force sensor of the present invention.

Figure 7 is a diagram showing the relative position relationship between the four three-way force sensors of the present invention and the center of the saddle.

Detailed ways

In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts should fall within the scope of protection of the present invention.

As shown in Figures 1 and 2, the embodiment of the present invention provides a six-way force measuring device for a tractor saddle, which includes a base plate 1 and a traction pin adapter 7; both ends of the base plate 1 are connected to the traction pin adapter 7 through a load-bearing beam 4 respectively. ;

A three-way force sensor 3 is provided between the two ends of each load beam 4 and the base plate 1 to obtain the force at different positions between the traction pin adapter 7 and the base plate 1 .

In some embodiments, a sensor force-measuring hole is provided on the bottom plate, and there are sensor mounting holes at both ends of the load-bearing beam. During installation, the sensor force-measuring hole and the sensor mounting hole are on the same central axis, and the connecting bolts pass through the sensor mounting holes and the three-way sensor mounting holes in sequence. The force sensor is connected to the preload nut. After installation, the preload nut is in the sensor installation hole.

The load beam is connected to the towing pin adapter via rubber bearings. When the traction pin adapter 7 receives the force and torque from the traction pin, the force and torque are transmitted to the three-way force sensor through the rubber bearing and the load-bearing beam. By decoupling the force on the three-way force sensor, the force and torque transmitted by the traction pin are obtained. Forces and moments.

As shown in Figure 3, the three-way force sensor includes a core shaft 31 and a connecting frame member 34; the core shaft 31 is connected to the connecting frame member 34 through a sensitive beam; strain gauges are respectively arranged on the sensitive beams.

The corresponding base plate is provided with fixing holes for fixing the three-way force sensor on the base plate;

A through hole is provided in the middle of the core shaft. During installation, the connecting bolt 2 passes through the sensor installation hole in sequence and the through hole of the three-way force sensor core shaft is connected to the preload nut 5.

The load beam 4 is connected to the traction pin adapter 7 through a rubber bearing 6 . When the traction pin adapter 7 receives the force and torque from the traction pin, the force and torque are transmitted to the three-way force sensor through the rubber bearing and the load-bearing beam. By decoupling the force on the three-way force sensor, the force and torque transmitted by the traction pin are obtained. Forces and moments.

It should be noted here that, as shown in Figure 2, the rubber bearing 6 includes a bearing pressure plate 61, a bearing bracket 62 and a bearing bushing 63;

The bearing bushing 63 is set on the bearing bracket 62;

The load-bearing beam 4 is provided with an installation groove, and a bearing bracket mounting hole is provided in the installation groove. The bearing pressure plate 61 is arranged in the installation groove. The bearing bracket 62 is arranged on the upper end of the bearing pressure plate 61 and is connected to the load-bearing beam through the bearing bracket installation hole. 4 connections;

Both ends of the bearing pressure plate 61 are provided with connection and fixing holes, and the bearing pressure plate is connected to the traction pin adapter 7 through the connection and fixation holes.

In some embodiments, the number of three-way force sensors is four, and the four three-way force sensors are realized by arranging four sensitive beams.

Four three-way force sensors use Wheatstone bridges to obtain forces in the three directions of X/Y/Z at the location.

One unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the X-direction. A total of four strain gauges form a Wheatstone full bridge for measuring the X-direction force;

One unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the Y direction. A total of four strain gauges form a Wheatstone full bridge for measuring the Y direction force;

A unidirectional strain gauge is arranged on the surface of the four sensitive beams, a total of eight strain gauges, forming a Wheatstone full bridge for measuring Z-direction force.

The force measuring components include a base plate, four three-way force sensors, four connecting bolts, four preload nuts, two load-bearing beams, two rubber bearings, two rubber bearing brackets, two rubber bearing pressure plates, traction pin adapters and Other fixing bolts; the bottom plate is punched and cut from a whole steel plate. There are bolt holes on both sides of the bottom plate for connection with the frame. There are sensor force measuring holes at the four corners of the bottom plate; the load-bearing beam There are sensor mounting holes at both ends, and there are rubber bearing bracket mounting holes and bolt holes in the middle; the base plate and the three-way force sensor are connected by bolts; the three-way force sensor and the load-bearing beam are connected by bolts; the load-bearing beam and the traction beam are connected by bolts. The pin adapter is connected through a rubber bearing; the rubber bearing is composed of a rubber bearing bracket, a rubber lining, and a rubber bearing pressure plate; the rubber bearing, the traction pin adapter, and the rubber pressure plate are connected through bolts, and the rubber bearing and the load-bearing beam are connected through the rubber bearing bracket and the load-bearing beam; The four three-way force sensors can respectively obtain the X/Y/Z three-way force at the location; the three-way force sensors are distributed in an array on the bottom plate.

The technical solution of the present invention also provides a force measurement calculation method based on a six-way force measurement device for a tractor saddle. The device includes a base plate 1, four connecting bolts 2, four three-way force sensors 3, and two load-bearing beams. 4. Composed of four preload nuts 5, two rubber bearing pressure plates 61, two rubber bearing brackets 62, two rubber linings 63, and traction pin adapter 7. Four sets of sensor mounting holes are arranged on the base plate. The base plate 1 and the three-way force sensor 3 are connected through bolts. The three-way force sensor 3 and the load-bearing beam 4 are connected through the connecting bolts 2. The load-bearing beam 4 is connected through the rubber bearing 6 and the traction pin adapter 7. The rubber bearing 6 includes a bearing pressure plate 61, a bearing bracket 62, and a bearing bushing 63. The bearing bracket 62 and the load beam 4 are connected by bolts. The bearing pressure plate 61 and the traction pin adapter 7 are connected by bolts. When the traction pin adapter 7 is affected by the traction pin When the force and moment are transmitted to the four three-way force sensors 3 through the rubber bearing 6 and the load-bearing beam 3, the force and moment transmitted by the traction pin are obtained by decoupling the forces on the four sensors and calculating.

The three-way force sensor 3 includes a connecting frame 34, a sensitive beam 32/33/35/36, and a core shaft 31; the four surfaces of the sensitive beam 32/33/35/36 are symmetrically arranged with unidirectional strain gauges; the sensitive beams 33, 36 Strain gauges X1/X2 and X3/X4 are arranged symmetrically on the left and right surfaces respectively, and connected in the order of X1-X3-X2-X4 to form a Wheatstone full bridge, as shown in Figure 4, to measure the X-direction force; sensitive beams 32, Strain gauges Y1/Y2 and Y3/Y4 are arranged symmetrically on the front and rear surfaces of 35 respectively, and are connected in the order of Y1-Y3-Y2-Y4 to form a Wheatstone full bridge, as shown in Figure 5, to measure the Y-direction force; sensitive beams 32, The upper and lower surfaces of 33, 35, and 36 are symmetrically arranged with strain gauges Z3/Z4, Z5/Z6, Z7/Z8, and Z1/Z2 respectively, and are connected in the order of Z1-Z5-Z2-Z6-Z3-Z7-Z4-Z8. The Wheatstone full bridge is shown in Figure 6, measuring the Z-direction force; the method includes the following steps:

Obtain the X/Y/Z-direction force collected by each three-way force sensor respectively and calculate the X/Y/Z-direction force at the center of the saddle based on the obtained force;

Obtain the distance in the X/Y direction from the center of each three-way force sensor to the center of the bottom plate respectively;

Based on the calculated X/Y/Z force at the center of the saddle and the obtained distance, the moments around the X/Y/Z direction at the center of the saddle are calculated respectively. The base plate can be identified as four independent zones, and the four three-way force sensors in their respective zones can be reasonably adjusted to the relative position of the saddle center as the structure changes.

Combined with Figure 7, based on the positional relationship between the sensor and the center of the bottom plate, the following calculation formula is obtained:

F _x =F _x1 +F _x2 +F _x3 +F _x4

F _y ＝F _y1 +F _y2 +F _y3 +F _y4

F _z ＝F _z1 +F _z2 +F _z3 +F _z4

M _x ＝F _z1 *W1-F _z2 *W2-F _z3 *W3+F _z4 *W4

M _y ＝F _z1 *L1+F _z2 *L2-F _z3 *L3-F _z4 *L4

M _z ＝-F _x1 *W1+F _x2 *W2+F _x3 *W3-F _x4 *W4-F _y1 *L1-F _y2 *L2+F _y3 *L3+F _y4 *L4

In the formula:

F _x ——X-direction force at the center of the saddle, F _x1 , F _x2 , F _x3 , and F _x4 are the X-direction forces of the four force sensors respectively;

F _y ——Y-direction force at the center of the saddle, F _y1 , F _y2 , F _y3 , and F _y4 are the Y-direction forces of the four force sensors respectively;

F _z ——X-direction force at the center of the saddle, F _z1 , F _z2 , F _z3 , and F _z4 are the Z-direction forces of the four force sensors respectively;

M _x - the moment about X at the center of the saddle;

M _y - the moment about Y at the center of the saddle;

M _z ——The moment about Z at the center of the saddle;

L1——X-direction distance from the center of the three-way force sensor 1 to the center of the bottom plate;

W1——Y-direction distance from the center of the three-way force sensor 1 to the center of the bottom plate;

L2——X-direction distance from the center of the three-way force sensor 2 to the center of the bottom plate;

W2——Y-direction distance from the center of the three-way force sensor 2 to the center of the bottom plate;

L3——X-direction distance from the center of the three-way force sensor 3 to the center of the bottom plate;

W3——Y-direction distance from the center of the three-way force sensor 3 to the center of the bottom plate;

L4——X-direction distance from the center of the three-way force sensor 4 to the center of the bottom plate;

W4——Y-direction distance from the center of the three-way force sensor 4 to the center of the bottom plate.

Although the present invention has been described in detail with reference to the accompanying drawings in conjunction with preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the invention, those of ordinary skill in the art can make various equivalent modifications or substitutions to the embodiments of the invention, and these modifications or substitutions should be within the scope of the invention/any Those skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention, and they should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims (10)

1. A six-directional force measuring device for a tractor saddle, which is characterized in that it includes a base plate and a traction pin adapter; both ends of the base plate are connected to the traction pin adapter through a load-bearing beam; A three-way force sensor is set between the two ends of each load-bearing beam and the bottom plate to obtain the force at different positions between the traction pin adapter and the bottom plate. 2. The six-direction force measuring device for a tractor saddle according to claim 1, characterized in that a sensor force measuring hole is provided on the bottom plate, and there are sensor installation holes at both ends of the load-bearing beam. During installation, the sensor force measuring hole is connected to the sensor force measuring hole. The sensor mounting hole is concentric with the central axis, and the connecting bolts pass through the sensor mounting hole in sequence, and the three-way force sensor is connected to the preload nut. After the installation is completed, the preload nut is in the sensor mounting hole. 3. The six-way force measuring device for a tractor saddle according to claim 2, characterized in that the three-way force sensor includes a mandrel and a connecting frame; the mandrel is connected to the connecting frame through a sensitive beam; Strain gauges are arranged on the sensitive beams. 4. The tractor saddle six-way force measuring device according to claim 3, characterized in that the base plate is provided with a fixing hole for fixing the three-way force sensor on the base plate; A through hole is provided in the middle of the core shaft. During installation, the connecting bolts pass through the sensor installation hole in sequence and the through hole of the three-way force sensor core shaft is connected to the preload nut. 5. The six-way force measuring device for a tractor saddle according to claim 4, characterized in that the load-bearing beam is connected to the traction pin adapter through a rubber bearing. 6. The tractor saddle six-way force measuring device according to claim 5, characterized in that the rubber bearing includes a bearing pressure plate, a bearing bracket and a bearing bushing; The bearing bushing is set on the bearing bracket; The load-bearing beam is provided with a mounting groove, a bearing bracket mounting hole is set in the mounting groove, the bearing pressure plate is set in the installation groove, the bearing bracket is set on the upper end of the bearing pressure plate and is connected to the load-bearing beam through the bearing bracket mounting hole; Both ends of the bearing pressure plate are provided with connection and fixing holes, and the bearing pressure plate is connected to the traction pin adapter through the connection and fixation holes. 7. The tractor saddle six-way force measuring device according to claim 6, characterized in that the number of three-way force sensors is four, and the four three-way force sensors are realized by setting four sensitive beams. 8. The tractor saddle six-way force measuring device according to claim 7, characterized in that the four three-way force sensors use Wheatstone bridges to obtain the forces in the three directions of X/Y/Z at the position. 9. The six-directional force measuring device for the tractor saddle according to claim 8, characterized in that a unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the Stone full bridge is used to measure X-direction force; One unidirectional strain gauge is arranged on the left and right sides of the two sensitive beams in the Y direction. A total of four strain gauges form a Wheatstone full bridge for measuring the Y direction force; A unidirectional strain gauge is arranged on the surface of each of the four sensitive beams, a total of eight strain gauges, forming a Wheatstone full bridge for measuring Z-direction force. 10. A force measurement calculation method based on the device according to claim 7, 8 or 9, characterized in that it includes the following steps: Obtain the X/Y/Z-direction force collected by each three-way force sensor respectively and calculate the X/Y/Z-direction force at the center of the saddle based on the obtained force; Obtain the distance in the X/Y direction from the center of each three-way force sensor to the center of the bottom plate respectively; Based on the calculated X/Y/Z force at the center of the saddle and the obtained distance, the moments around the X/Y/Z direction at the center of the saddle are calculated respectively.