A transport vehicle differential

Abstract

The present invention provides a transport vehicle differential, belonging to the technical field of transport vehicles. It solves the problem that the existing transport vehicles have large turning resistance and are not smooth. The transport vehicle differential includes an outer rotating body with a center hole and an inner rotating body rotatably matched in the center hole. The center hole wall of the outer rotating body is provided with at least three radially arranged mounting holes, and the mounting holes are circumferentially distributed. An annular damping groove is circumferentially provided on the outer peripheral surface of the inner rotating body. Damping steel balls and elastic parts are provided in the mounting holes. Under the action of the elastic parts, the damping steel balls are pressed in the damping grooves. At least three circumferentially distributed mounting holes are also provided with limit columns that can support and limit the damping steel balls when the damping steel balls have a tendency to move into the mounting holes. The transport vehicle differential makes turning resistance small and smoother.

Description

Technical Field

[0001] The invention belongs to the technical field of transport vehicles and relates to a transport vehicle differential. Background Art

[0002] A transport truck is a logistics handling equipment for transporting goods. When the transport truck is used at a handling station, the fork it carries is inserted into the hole of the pallet, and the hydraulic system is driven to lift and lower the pallet goods. The handling operation is completed by human pulling or motor drive. It is the simplest, most effective and most common loading and unloading and handling tool among the pallet transport tools at the handling station. For electric transport trucks, the motor drives the drive shaft to rotate, and a drive shaft drives the wheels at both ends to rotate. When the transport truck needs to turn, the turning radius of the wheels on the left and right sides is different. Since the two wheels have the same rotation speed, the wheel with a larger turning radius will slip relative to the ground to compensate for the larger stroke, so there will be friction noise, and the rolling and sliding of the wheel are intertwined, resulting in an unsmooth turn.

[0003] In response to the above problems, the patent document (201320455163.X) discloses a simple vehicle differential mechanism for a transport vehicle, including an outer wheel seat and an inner wheel seat, the inner wheel seat is provided with two opposite radial through holes, the wheel axle sleeve and the wheel axle connecting shaft are provided with radially penetrating screw through holes, a connecting screw passes through the radial through holes on the inner wheel seat and the screw through holes on the wheel axle sleeve and the wheel axle connecting shaft to connect the driving wheel seat and the wheel axle connecting shaft, so that the wheel axle connecting shaft can drive the driving wheel seat and the tire to rotate, the radial through holes on the inner wheel seat form strip holes on the circumference, and the connecting screw can rotate with the inner wheel seat through the strip holes, that is, the driving wheel seat and the wheel axle connecting shaft can rotate relative to each other. This structure cooperates with the strip hole through the connecting screw rod, so that the driving wheel seat and the wheel axle connecting shaft can rotate relative to each other when turning. However, since the length of the strip hole is limited, when the turning stroke is large, the length of the strip hole is difficult to meet the relative rotation angle. At the same time, when there are multiple consecutive turns, the screw rod that has been against the strip hole is difficult to return to its position, and the driving wheel seat and the wheel axle connecting shaft are also difficult to rotate relative to each other, which still causes the wheel to slip against the ground, thereby making the truck turn less smoothly. Summary of the invention

[0004] The purpose of the present invention is to solve the above problems in the existing technology and propose a transport vehicle differential to solve the problem that the existing transport vehicles have large turning resistance and are not smooth.

[0005] The objectives of the present invention can be achieved through the following technical solutions: a transport vehicle differential, comprising an outer rotating body for connecting to wheels and having a center hole, and an inner rotating body for connecting to a drive shaft and rotatably fitting in the center hole of the outer rotating body, characterized in that at least three radially arranged mounting holes are provided on the wall of the center hole of the outer rotating body, and the mounting holes are distributed circumferentially, an annular damping groove is circumferentially provided on the outer circumferential surface of the inner rotating body, damping steel balls and elastic parts are provided in the mounting holes, and the damping steel balls are pressed in the damping grooves under the action of the elastic parts, and at least three circumferentially distributed mounting holes are also provided with limit columns that can support and limit the damping steel balls when the damping steel balls have a tendency to move into the mounting holes.

[0006] The drive shaft is connected to the inner rotating body, and the wheel is fixed on the outer rotating body. An elastic member and a damping steel ball are arranged in the mounting hole of the outer rotating body. The elastic member presses the damping steel ball tightly into the damping groove of the inner rotating body. Therefore, the multiple damping steel balls distributed circumferentially will generate a large friction resistance with the damping groove, thereby realizing the circumferential positioning of the inner rotating body and the outer rotating body within a certain load range. When the transport vehicle travels in a straight line, the wheel and the ground generate rolling friction. The rolling friction force is smaller than the friction resistance between the damping steel ball and the damping groove. Therefore, the inner rotating body and the outer rotating body are always circumferentially positioned. The drive shaft drives the wheel to rotate through the inner rotating body and the outer rotating body. When turning is required, since the rotation speeds of the two inner rotating bodies are the same, but the wheel with a larger turning radius requires a larger travel in the same time, the wheel with a larger turning radius will have a tendency to slide with the ground, that is, the ground will generate sliding friction resistance to the wheel, and the sliding friction resistance is greater than the friction resistance between the damping steel ball and the damping groove, thereby causing the damping steel ball to roll in the damping groove. Or slide, realize the relative rotation of the outer rotating body and the inner rotating body, so that the speed of the wheel with a larger turning radius becomes faster, avoiding sliding friction between the wheel and the ground, reducing noise and making turning smoother. At the same time, unlike the existing differential, which basically has no radial force or small radial force, the cargo weight of the transport vehicle will be applied to the drive shaft and then to the inner rotating body, causing the inner rotating body to have a tendency to be eccentric downward relative to the outer rotating body. For this purpose, limit columns are arranged in at least three mounting holes distributed circumferentially, so that at least one limit column is located below the axial center line of the drive shaft. When the inner rotating body has a tendency to move eccentrically downward relative to the outer rotating body, the limit column can support the damping steel ball and then support the inner rotating body. That is, multiple limit columns can ensure the concentricity between the inner rotating body and the outer rotating body, avoid friction caused by contact and abutment between the lower part of the inner rotating body and the lower part of the outer rotating body due to excessive load, reduce friction resistance and noise generated during the friction between the two, and make turning smoother.

[0007] In the above-mentioned transport vehicle differential, the mounting holes on the outer rotating body are evenly distributed in the circumference, and the mounting holes provided with the limiting posts are evenly distributed in the circumference. The mounting holes are evenly distributed in the circumference, so the damping steel balls are also evenly distributed in the circumference, thereby generating uniform friction resistance on the inner rotating body, and the limiting posts are also evenly distributed in the circumference, so that at least one limiting post can be ensured to be located below the axis of the drive shaft to support the inner rotating body, ensure the concentricity of the inner rotating body and the outer rotating body, avoid excessive friction resistance between the inner rotating body and the outer rotating body, and ensure smooth driving.

[0008] In the above-mentioned transport vehicle differential, an adjusting bolt is also screwed into the mounting hole, and the limiting column is located between the adjusting bolt and the damping steel ball, and when the damping steel ball has a tendency to move into the mounting hole, the outer end of the limiting column can abut against the adjusting bolt, and the inner end can abut against the damping steel ball to support and limit the damping steel ball. The limiting column supports and limits the damping steel ball by abutting against the adjusting bolt, and the position of the limiting column can be adjusted by the adjusting bolt, so that the two ends of the limiting column are better in contact with the damping steel ball and the adjusting bolt without being pressed. Of course, there can also be a slight gap, which should be smaller than the assembly gap between the inner rotating body and the outer rotating body, so as to support and limit the damping steel ball when it has a tendency to move into the mounting hole.

[0009] In the above-mentioned transport vehicle differential, the elastic member includes a coil spring, one end of which abuts against the damping steel ball, and the other end abuts against the adjusting bolt. When a limit column is provided in the mounting hole, the limit column is inserted into the coil spring. The pre-tightening force of the coil spring on the damping steel ball can be adjusted by adjusting the bolt, thereby adjusting the friction resistance between the damping steel ball and the damping groove to be suitable for ground surfaces with different friction coefficients.

[0010] In the above-mentioned transport vehicle differential, the outer diameter of the limit post is slightly smaller than the inner diameter of the coil spring. The limit post can limit the coil spring to prevent it from bending, etc., and the coil springs abutting at both ends can also limit the limit post to prevent it from tilting.

[0011] In the above-mentioned transport vehicle differential, an annular groove is opened circumferentially on the bottom surface of the damping groove, an O-ring is sleeved in the annular groove, the wire diameter of the O-ring is greater than the depth of the annular groove, the damping steel ball presses the O-ring and abuts against the wall of the damping groove, and the O-ring is made of rubber or silicone material. Since the damping steel ball and the inner rotating body are both metal parts, an annular groove is opened at the bottom of the damping groove and an O-ring is set. The damping steel ball presses against the O-ring, which can increase the friction resistance between the damping steel ball and the inner rotating body, avoid the relative rotation of the inner rotating body and the outer rotating body when driving in a straight line, and ensure the stability of driving in a straight line, and the setting of the annular groove can prevent the O-ring from being damaged by excessive extrusion.

[0012] In the above-mentioned transport vehicle differential, the cross section of the damping groove is arc-shaped, and the cross section radius of the damping groove is consistent with the radius of the damping steel ball, so that the damping steel ball forms a line contact with the wall of the damping groove, increasing the friction resistance between the two, thereby ensuring the stability of straight-line driving, and at the same time, the axial positioning of the outer rotating body and the inner rotating body is also achieved by the damping steel ball pressing against the damping groove.

[0013] In the above-mentioned transport vehicle differential, the annular groove is located in the middle of the damping groove in the width direction, so that the friction force of the inner rotating body is more symmetrical and the stability is ensured.

[0014] In the above-mentioned transport vehicle differential, the outer rotor and the inner rotor are both cylindrical, and a disc-shaped portion is circumferentially provided on the outer circumference of the outer rotor, and the outer end of the above-mentioned mounting hole penetrates the outer circumference of the disc-shaped portion, and the damping groove is located in the axial middle of the inner rotor. The disc-shaped portion provides space for the installation hole, and the disc-shaped portion protrudes from the outer circumference of the outer rotor, so that the connection of the wheel is more firm and stable, and the damping groove is located in the axial middle of the inner rotor, so that the force is more uniform.

[0015] In the above-mentioned transport vehicle differential, the outer end hole wall of the mounting hole has an internal thread matched with the adjusting bolt, and the damping steel ball is transitionally matched with the inner end hole wall of the mounting hole. The inner end of the mounting hole plays a role in keeping the damping steel ball limited, thereby ensuring stability.

[0016] Compared with the prior art, the differential of this transporter has the following advantages:

[0017] 1. Since elastic parts and damping steel balls are arranged in the mounting holes, the elastic parts press the damping steel balls tightly into the damping grooves of the inner rotating body. Therefore, the multiple damping steel balls distributed circumferentially will generate greater friction resistance with the damping grooves. When turning is required, the ground will generate sliding friction resistance to the wheels with a larger turning radius, so that the damping steel balls roll or slide in the damping grooves, realizing the relative rotation of the outer rotating body and the inner rotating body, avoiding the sliding friction between the wheels and the ground, reducing noise and making turning smoother.

[0018] 2. Since limit columns are arranged in at least three mounting holes distributed circumferentially, the limit columns can support the damping steel ball when the inner rotating body has a tendency to move eccentrically downward relative to the outer rotating body, that is, multiple limit columns can ensure the concentricity between the inner rotating body and the outer rotating body, avoid friction between the lower part of the inner rotating body and the lower part of the outer rotating body due to excessive load, reduce frictional resistance and noise generated during the friction between the two, and make turning smoother.

[0019] 3. Since an annular groove is opened at the bottom of the damping groove and an O-ring is arranged, the damping steel ball presses against the O-ring, which can increase the friction resistance between the damping steel ball and the inner rotating body, avoid the relative rotation of the inner rotating body and the outer rotating body during straight-line driving, and ensure the stability of straight-line driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a cross-sectional view of the transverse structure of the transporter differential.

[0021] Figure 2 It is a longitudinal structural cross-sectional view of the transporter differential.

[0022] Figure 3 yes Figure 2 A magnified view of the structure at center.

[0023] Figure 4 It is a cross-sectional view of the transverse structure of the transport vehicle differential in the second embodiment.

[0024] In the figure, 1, outer rotating body; 11, center hole; 12, mounting hole; 13, disc-shaped part; 2, inner rotating body; 21, damping groove; 22, annular groove; 23, spline groove; 3, damping steel ball; 4, spiral spring; 5, adjusting bolt; 6, limit column; 7, O-ring. DETAILED DESCRIPTION

[0025] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0026] Embodiment 1:

[0027] like Figure 1As shown, a transport vehicle differential comprises an inner rotor 2 and an outer rotor 1, wherein the inner rotor 2 and the outer rotor 1 are both cylindrical, so that the outer rotor 1 has a center hole 11, and the wall thickness of the outer rotor 1 is greater than the wall thickness of the inner rotor 2, and the inner rotor 2 is rotatably arranged in the center hole 11 of the outer rotor 1, so that the inner circumference of the outer rotor 1 and the outer circumference of the inner rotor 2 are circumferentially slidably matched, wherein the inner hole wall of the inner rotor 2 is provided with a spline groove 23 for connecting to the driving shaft of the transport vehicle, and the axial middle part of the outer circumference of the outer rotor 1 is provided with a protruding disc-shaped portion 13 for connecting to the wheel, and the wheel is coated on the disc-shaped portion 13 and the outer circumference of the outer rotor 1 in a rubber-coated manner. At least three mounting holes 12 are opened on the wall of the center hole 11 of the outer rotating body 1. The number of mounting holes 12 is set according to the friction resistance required for the circumferential positioning of the outer rotating body 1 and the inner rotating body 2 and the size of the outer rotating body 1. In this embodiment, the number of mounting holes 12 is preferably 10, and the 10 mounting holes 12 are evenly distributed in the circumference, and each mounting hole 12 is arranged along the radial direction of the outer rotating body 1. The outer end of the mounting hole 12 passes through the outer peripheral surface of the disc-shaped portion 13. A damping steel ball 3, a coil spring 4 and an adjusting bolt 5 are arranged in each mounting hole 12. The outer end hole wall of the mounting hole 12 has an internal thread, and the adjusting bolt 5 is screwed at the outer end of the mounting hole 12. The damping steel ball 3 is arranged in the mounting hole At the inner end of 12, the outer diameter of the damping steel ball 3 is slightly smaller than the aperture of the inner end of the mounting hole 12, so that the damping steel ball 3 is transitionally matched with the inner end hole wall of the mounting hole 12, and the coil spring 4 is arranged between the adjusting bolt 5 and the damping steel ball 3. An annular damping groove 21 is circumferentially opened on the outer circumferential surface of the inner rotating body 2, and the damping groove 21 is located in the axial middle part of the inner rotating body 2. One end of the coil spring 4 abuts on the inner end surface of the adjusting bolt 5, and the other end abuts on the damping steel ball 3. Under the action of the coil spring 4, the damping steel ball 3 is pressed in the damping groove 21, and the circumferential positioning of the outer rotating body 1 and the inner rotating body 2 is realized by the friction resistance between the damping steel ball 3 and the damping groove 21, so that the transport vehicle can travel stably in a straight line.

[0028] Specifically, combined Figure 2 , Figure 3As shown, at least three mounting holes 12 are further provided with limiting columns 6, and five limiting columns 6 are preferably provided in this embodiment. The five limiting columns 6 are evenly distributed in the circumferential direction, that is, the mounting holes 12 provided with limiting columns 6 and the mounting holes 12 not provided with limiting columns 6 are evenly spaced in the circumferential direction. One end of the limiting column 6 faces the adjusting bolt 5 and can contact the end face of the adjusting bolt 5, and the other end faces the damping steel ball 3 and can contact the damping steel ball 3, so that when the damping steel ball 3 has a tendency to move into the mounting hole 12, the limiting column 6 supports and limits it. The outer diameter of the limiting column 6 is slightly smaller than the inner diameter of the coil spring 4, and the limiting column 6 is penetrated inside the coil spring 4. The cross section of the damping groove 21 is arc-shaped, and the cross-sectional radius of the damping groove 21 is consistent with the radius of the damping steel ball 3, so that the damping steel ball 3 forms a linear contact with the groove wall of the damping groove 21. An annular groove 22 is circumferentially opened on the bottom surface of the damping groove 21, and the annular groove 22 is located in the middle of the width direction of the damping groove 21. An O-ring 7 is sleeved in the annular groove 22. The O-ring 7 is made of a material with a large friction coefficient such as rubber or silicone. The wire diameter of the O-ring 7 is greater than the depth of the annular groove 22. The damping steel ball 3 presses the O-ring 7 and abuts against the wall of the damping groove 21.

[0029] The coil spring 4 presses the damping steel ball into the damping groove 21 of the inner rotor 2, and a large friction resistance is generated between the damping steel ball 3 and the damping groove 21 and the O-ring 7, thereby realizing the circumferential positioning of the inner rotor 2 and the outer rotor 1 within a certain load range. When the transport vehicle travels in a straight line, rolling friction is generated between the wheel and the ground. The rolling friction force is smaller than the friction resistance between the damping steel ball 3 and the damping groove 21. Therefore, the inner rotor 2 and the outer rotor 1 are always circumferentially positioned. The driving shaft drives the wheel to rotate through the inner rotor 2 and the outer rotor 1. When turning is required, the sliding friction resistance between the wheel and the ground is greater than the friction resistance between the damping steel ball 3 and the damping groove 21, thereby causing the damping steel ball 3 to roll or slide in the damping groove 21, realizing the relative rotation of the outer rotor 1 and the inner rotor 2, thereby increasing the rotation speed of the wheel with a larger turning radius, avoiding the sliding friction between the wheel and the ground, reducing noise and making turning smoother.

[0030] Embodiment 2:

[0031] The structure of the transport vehicle differential is basically the same as that of the first embodiment. The difference is that Figure 4 As shown, a limiting column 6 is provided in each mounting hole 12 , thereby providing a stable limiting support for each damping steel ball 3 .

[0032] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0033] Although the terminology such as outer rotor 1, center hole 11, mounting hole 12 is used more frequently in this article, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A truck differential, comprising an outer rotor (1) for connecting to a wheel and having a center hole (11) and an inner rotor (2) for connecting to a drive shaft and rotatably engaged in the center hole (11) of the outer rotor (1), characterized in that: At least three radially arranged mounting holes (12) are provided on the wall of the central hole (11) of the outer rotating body (1), and the mounting holes (12) are circumferentially distributed. An annular damping groove (21) is circumferentially provided on the outer peripheral surface of the inner rotating body (2). A damping steel ball (3) and an elastic member are provided in each of the mounting holes (12). Under the action of the elastic member, the damping steel ball (3) is pressed into the damping groove (21). At least three circumferentially distributed mounting holes (12) are further provided with a limiting column (6) capable of supporting and limiting the damping steel ball (3) when the damping steel ball (3) has a tendency to move into the mounting hole (12); an adjusting bolt (5) is also screwed in the mounting hole (12), and the limiting column (6) is located between the adjusting bolt (5) and the damping steel ball (3). ), and when the damping steel ball (3) has a tendency to move into the mounting hole (12), the outer end of the limiting column (6) can abut against the adjusting bolt (5), and the inner end can abut against the damping steel ball (3) to support and limit the damping steel ball (3); an annular groove (22) is circumferentially opened on the bottom surface of the damping groove (21), an O-ring (7) is sleeved in the annular groove (22), the wire diameter of the O-ring (7) is greater than the depth of the annular groove (22), the damping steel ball (3) presses the O-ring (7) and abuts against the groove wall of the damping groove (21), the O-ring (7) is made of rubber or silicone material, the cross-section of the damping groove (21) is arc-shaped, and the cross-sectional radius of the damping groove (21) is consistent with the radius of the damping steel ball (3).

2. The transport vehicle differential according to claim 1, characterized in that: The elastic member comprises a coil spring (4), one end of the coil spring (4) abuts against the damping steel ball (3), and the other end abuts against the adjusting bolt (5); when a limiting column (6) is provided in the mounting hole (12), the limiting column (6) is inserted into the coil spring (4).

3. The transport vehicle differential according to claim 2, characterized in that: The outer diameter of the limiting column (6) is slightly smaller than the inner diameter of the coil spring (4).

4. The transport vehicle differential according to any one of claims 1 to 3, characterized in that: The annular groove (22) is located in the middle of the damping groove (21) in the width direction.

5. The transport vehicle differential according to any one of claims 1 to 3, characterized in that: The outer rotating body (1) and the inner rotating body (2) are both cylindrical, and a disc-shaped portion (13) is circumferentially provided on the outer circumferential surface of the outer rotating body (1), the outer end of the mounting hole (12) penetrates the outer circumferential surface of the disc-shaped portion (13), and the damping groove (21) is located in the axial middle part of the inner rotating body (2).

6. The transport vehicle differential according to claim 2 or 3, characterized in that: The outer end hole wall of the mounting hole (12) has an internal thread that matches the adjusting bolt (5), and the damping steel ball (3) is transitionally matched with the inner end hole wall of the mounting hole (12).

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