CN211951037U - Digital hydraulic cylinder and excavator - Google Patents

Abstract

The utility model discloses a digital hydraulic cylinder and an excavator, which relate to the technical field of hydraulic drive. It includes a hydraulic cylinder body and a control assembly arranged on the hydraulic cylinder body; wherein, one end of the first ball screw is fixedly connected with the output end of the driving motor, and the other end is drivingly connected with the first screw nut, and the first screw nut is connected to the output end of the driving motor. The first end of the valve core is connected; one end of the second ball screw is connected with the second end of the valve core, the second ball screw is drivingly connected with the second screw nut, and the second screw nut is rotatably connected with the valve body; The second screw nut is provided with helical teeth in the circumferential direction, and the hydraulic cylinder body is also provided with a helical rack that slides in the direction of the axis of the valve core. . The precise control of the hydraulic cylinder can be realized without changing the internal structure of the hydraulic cylinder, thereby simplifying the installation structure and facilitating later maintenance.

Description

A digital hydraulic cylinder and excavator

technical field

The utility model relates to the technical field of hydraulic drive, in particular to a digital hydraulic cylinder and an excavator.

Background technique

Hydraulic cylinder is an energy replacement device that converts hydraulic energy into mechanical energy, and is an actuator commonly used in hydraulic systems. In the traditional hydraulic control system, the output force, speed and position of the hydraulic cylinder are controlled in the whole system by external hydraulic components, so precise adjustment control cannot be achieved.

With the needs of the social industry, the precision of hydraulic component control is higher, and the traditional hydraulic control system cannot meet today's higher requirements. Therefore, in order to achieve the demand for precise control, digital hydraulic cylinders came into being. The ball screw is installed inside the digital hydraulic cylinder and is connected with the valve core to accurately control the position of the hydraulic cylinder piston. By changing the pulse frequency received by the stepping motor, the movement speed of the piston is adjusted. The piston position is controlled by stepping The number of electrical pulses received by the motor is determined.

However, in the existing digital hydraulic cylinder, the ball screw, the valve core, etc. are arranged inside the hydraulic cylinder, and the internal structure of the hydraulic cylinder needs to be re-processed and transformed, which makes assembly difficult and is not conducive to problems such as later maintenance.

Utility model content

The purpose of the utility model is to provide a digital hydraulic cylinder and an excavator, which can realize precise control of the hydraulic cylinder without changing the internal structure of the hydraulic cylinder, thereby simplifying the installation structure and facilitating later maintenance.

The embodiment of the present utility model is realized in this way:

In one aspect of the embodiments of the present invention, a digital hydraulic cylinder is provided, which includes a hydraulic cylinder body and a control assembly arranged on the hydraulic cylinder body; the hydraulic cylinder body includes a cylinder body and a piston rod arranged in the cylinder body. The cylinder body is divided into a rod cavity and a rodless cavity; the control assembly includes a drive motor capable of receiving pulse signals, a slide valve, a first ball screw, a first screw nut, a second ball screw, and a second screw nut, The slide valve includes a valve body arranged on the body of the hydraulic cylinder and a valve core arranged in the valve body, the valve core can move axially along the valve body; one end of the first ball screw is fixedly connected with the output end of the driving motor, and the other end is connected with the The first screw nut is connected by transmission, and the first screw nut is connected with the first end of the valve core; one end of the second ball screw is connected with the second end of the valve core, and the second ball screw is driven with the second screw nut connection, the second screw nut is rotatably connected with the valve body; the valve body is provided with a plurality of oil passage through holes, wherein the first oil passage through hole in the plurality of oil passage through holes is communicated with the rod cavity, and the plurality of oil passage through holes are connected with the rod cavity. The second oil passage through hole in the passage through hole is communicated with the rodless cavity; the second screw nut is provided with helical teeth in the circumferential direction, and the hydraulic cylinder body is also provided with a helical rack that slides in the direction of the axis where the valve core is located. The rack and the helical teeth are engaged for transmission, and the helical rack is fixedly connected with the piston rod through the connecting rod.

Optionally, the control assembly further includes a first coupling and a second coupling, the first screw nut is connected with the first end of the valve core through the first coupling, and the second ball screw is connected through the second coupling The device is connected to the second end of the valve core.

Optionally, both the first coupling and the second coupling are universal joints.

Optionally, the inner wall of the valve is provided with a limiting groove, and the valve core is correspondingly provided with a limiting protrusion that cooperates with the limiting groove, or the inner wall of the valve is provided with a protrusion, and the valve core is correspondingly provided with a protrusion that cooperates with the protrusion. so that the spool can only move along the axis of the spool.

Optionally, the hydraulic cylinder body is provided with a chute along the direction of the valve core axis, and the helical rack is provided with a slide rail correspondingly, or, the hydraulic cylinder body is provided with a guide slide rail along the valve core axis direction, and the helical rack A guide chute is correspondingly arranged on the upper part, so that the helical rack slides along the direction of the axis where the valve core is located.

Optionally, the cross section of the chute or guide chute is trapezoidal or rectangular.

Optionally, the regulating assembly further includes a bearing, and the bearing is arranged between the second lead screw nut and the valve body, so that the second lead screw nut and the valve body are rotatably connected.

Optionally, a connecting seat is provided at one end of the first ball screw away from the first screw nut, and the first ball screw is fixedly connected to the output end of the driving motor through the connecting seat.

Optionally, the regulating assembly further includes a protective shell, the protective shell is arranged on the side of the valve body close to the driving motor, and the driving motor, the first ball screw and the first screw nut are all located in the protective shell.

Another aspect of the embodiment of the present invention provides an excavator, comprising a working arm and a bucket connected to each other, and a digital hydraulic cylinder as described in any of the above, wherein the digital hydraulic cylinder is arranged on the working arm and is driven with the bucket. connect.

The beneficial effects of the embodiments of the present utility model include:

The digital hydraulic cylinder and the excavator provided by the embodiments of the present invention facilitate the integrated control of the hydraulic cylinder through the hydraulic cylinder body and the provided through-hole components on the hydraulic cylinder body without changing the internal structure of the hydraulic cylinder. One end of the first ball screw is fixedly connected to the output end of the driving motor, and the other end is drivingly connected to the first screw nut. When the driving motor moves according to the pulse signal, the output end of the driving motor drives the first ball screw. Synchronous movement, the rotation of the first ball screw drives the first screw nut to move in the direction of the axis of the first ball screw. Since the first screw nut is connected to the first end of the valve core, the first screw nut drives the valve core to move axially when it moves, and the axial movement of the valve core makes the first oil passage on the valve body communicate with the rod cavity , the second oil passage through hole communicates with the rodless cavity, thereby forming a hydraulic passage and driving the piston rod to move. When the piston rod moves, the helical rack, which is fixedly connected to the piston rod through the connecting rod, moves synchronously with the piston rod. Due to the meshing transmission between the helical rack and the helical teeth arranged in the circumferential direction of the second lead screw nut, the piston rod will drive the second screw when it moves. The screw nut turns. The second ball screw is drivingly connected with the second screw nut. When the second screw nut rotates, the second ball screw moves axially, thereby driving the valve core to move axially, and the movement direction and the driving motor drive the valve core to move. The directions are reversed to form a mechanical negative feedback. In this way, the hydraulic passage can be closed, thereby stopping the movement of the piston rod. The above movement is a micro-step of the movement of the digital hydraulic cylinder. If the piston rod needs to move continuously, it needs to send a pulse signal to the drive motor at a specific frequency. Whenever the drive motor receives the pulse signal, the spool is controlled to move, so that the oil circuit is connected. The hole opens a small displacement to form a hydraulic passage. The high-pressure oil pushes the piston rod to move the corresponding distance and closes the oil passage through hole to stop the piston rod. When working, the digital hydraulic cylinder continues this action to complete the required propulsion. Through the above structure, precise control of the hydraulic cylinder can be achieved without changing the internal structure of the hydraulic cylinder, thereby simplifying the installation structure and facilitating later maintenance.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings that need to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention. Therefore, it should not be regarded as a limitation of the scope. For those of ordinary skill in the art, other related drawings can also be obtained from these drawings without any creative effort.

1 is one of the schematic structural diagrams of a digital hydraulic cylinder provided by an embodiment of the present invention;

2 is a schematic structural diagram of a control assembly provided by an embodiment of the present invention;

3 is a schematic structural diagram of a double-cross universal joint provided by an embodiment of the present utility model;

4 is one of the schematic cross-sectional views of the valve body and the valve core limit position provided by the embodiment of the present invention;

5 is the second schematic cross-sectional view of the valve body and the valve core limit position provided by the embodiment of the present invention;

FIG. 6 is the second schematic diagram of the structure of the digital hydraulic cylinder provided by the embodiment of the present invention.

Icon: 100-digital hydraulic cylinder; 110-hydraulic cylinder body; 111-cylinder body; 1112-rod cavity; 1114-rodless cavity; 112-piston rod; 114-chute; 120-regulating assembly; 121-drive motor ;122-slide valve;1222-valve body;1222a-limiting groove;1222b-protrusion;1224-spool;1224a-limiting protrusion;1224b-groove;1226-first oil passage hole;1228 -2nd oil passage through hole; 123-1st ball screw; 1232-connector; 124-1st screw nut; 125-2nd ball screw; 126-2nd screw nut; 1262-bearing; 127 -Helical rack; 1272-Slide rail; 128-First coupling; 129-Second coupling; 130-Connecting rod; 140-Universal coupling; 142-First connecting part; 144-Second Connection part; 146-rotation part; 150-protective shell.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. The embodiments described above are a part of the embodiments of the present invention, but not all of the embodiments. The components of the embodiments of the invention generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Accordingly, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures. Furthermore, the terms "first", "second", etc. are only used to differentiate the description and should not be construed to indicate or imply relative importance.

In the description of the present utility model, it should also be noted that, unless otherwise expressly specified and limited, the terms "arrangement" and "connection" should be understood in a broad sense, for example, it may be a fixed connection or a detachable connection, Or integrally connected; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

Referring to FIG. 1 , this embodiment provides a digital hydraulic cylinder 100 , which includes a hydraulic cylinder body 110 and a control assembly 120 disposed on the hydraulic cylinder body 110 ; the hydraulic cylinder body 110 includes a cylinder body 111 and a The piston rod 112, the piston rod 112 divides the cylinder 111 into a rod cavity 1112 and a rodless cavity 1114; the control assembly 120 includes a drive motor 121 capable of receiving pulse signals, a slide valve 122, a first ball screw 123, a first wire The screw nut 124, the second ball screw 125, the second screw nut 126, the spool valve 122 includes a valve body 1222 arranged on the hydraulic cylinder body 110 and a valve core 1224 arranged in the valve body 1222, the valve core 1224 can move along the The valve body 1222 moves axially; one end of the first ball screw 123 is fixedly connected to the output end of the driving motor 121 , and the other end is drivingly connected to the first screw nut 124 , which is connected to the first screw nut 124 of the valve core 1224 One end of the second ball screw 125 is connected with the second end of the valve core 1224, the second ball screw 125 is drivingly connected with the second screw nut 126, and the second screw nut 126 is rotatably connected with the valve body 1222; The valve body 1222 is provided with a plurality of oil passage through holes, wherein the first oil passage through hole 1226 of the plurality of oil passage through holes communicates with the rod cavity 1112, and the second oil passage of the plurality of oil passage through holes communicates with the rod cavity 1112. The hole 1228 communicates with the rodless cavity 1114; the second screw nut 126 is circumferentially provided with helical teeth, and the hydraulic cylinder body 110 is also provided with a helical rack 127 that slides in the direction of the axis of the valve core 1224. The helical teeth are engaged for transmission, and the helical rack 127 is fixedly connected to the piston rod 112 through the connecting rod 130 .

It should be noted that, first, the piston rod 112 includes a push rod and a piston connected to one end of the push rod. The piston divides the hydraulic cylinder body 110 into a rod chamber 1112 and a rodless chamber 1114 that are not connected to each other, that is, the piston rod 112 will The cylinder block 111 is divided into a rod cavity 1112 and a rodless cavity 1114 . The rod cavity 1112 refers to the cavity space with the push rod, and the rodless cavity 1114 refers to the cavity space without the push rod.

Second, the driving motor 121 that can receive the pulse signal includes a stepping motor and a servo motor. The driving motor 121 used in this embodiment may be a stepping motor or a servo motor, as long as the normal operation of the control assembly 120 can be ensured Just work. In addition, the pulse signal includes a positive pulse and a negative pulse to control the forward rotation and inversion of the driving motor 121 , thereby controlling the extension and retraction of the piston rod 112 .

Third, the slide valve 122 of this embodiment adopts a reciprocating structure, the valve core 1224 can move axially along the valve body 1222 , the valve core 1224 is provided with a shoulder, and the valve body 1222 is provided with a ring groove. The spool valve 122 forms the size and position of the orifice by controlling the spool 1224 to slide in the valve body 1222, so as to control the flow through the through hole of the oil passage. 1 and 2, in the initial state, the valve core 1224 is in the neutral position, and at this time, the hydraulic oil inlet P and the first oil passage through hole 1226 and the second oil passage through hole 1228 are in a disconnected state . When the driving motor 121 receives a positive pulse, the driving motor 121 moves, thereby driving the valve core 1224 to move to the right through the first ball screw 123 and the first screw nut 124, so that the hydraulic oil inlet P on the valve body 1222 is sequentially connected to the The second oil passage through hole 1228 communicates with the oil port B at the rodless cavity 1114 , and the oil return port T on the valve body 1222 communicates with the first oil passage through hole 1226 and the oil port A at the rod cavity 1112 in turn. When the piston rod 112 is extended, the valve core 1224 is reset to the initial state under the action of mechanical negative feedback. Similarly, when the driving motor 121 receives a negative pulse, the driving motor 121 moves, thereby driving the valve core 1224 to move leftward through the first ball screw 123 and the first screw nut 124, so that the hydraulic oil inlet on the valve body 1222 P is communicated with the first oil passage through hole 1226 and the oil port A at the rod cavity 1112 in turn, and the oil return port T on the valve body 1222 is sequentially connected with the second oil passage through hole 1228 and the oil port at the rodless cavity 1114. B is connected. When the piston rod 112 is retracted, the valve core 1224 is reset to the initial state under the action of mechanical negative feedback. In addition, according to the different rotation directions of the first ball screw 123 and the first screw nut 124 , when the driving motor 121 receives a positive pulse, the piston rod 112 retracts; when the driving motor 121 receives a negative pulse , the piston rod 112 extends.

Fourth, when the piston rod 112 extends, the connecting rod 130 drives the helical rack 127 to move synchronously, and the helical rack 127 meshes with the helical teeth provided in the circumferential direction of the second lead screw nut 126. It is rotatably connected with the valve body 1222, and the second ball screw 125 is connected with the second screw nut 126 in a driving connection, and one end of the second ball screw 125 is connected with the second end of the valve core 1224, so that the piston rod 112 drives the helical teeth The bar 127 moves, the helical rack 127 drives the second lead screw nut 126 to move, the second lead screw nut 126 drives the second ball screw 125 to move, and the second ball screw 125 drives the valve core 1224 to return to the initial state to form a mechanical Negative feedback. Similarly, when the piston rod 112 is retracted, the valve core 1224 also needs to be restored to the initial state according to the connection relationship. In addition, when the transmission is specifically connected, the inclination direction of the helical teeth provided in the circumferential direction of the helical rack 127 and the second screw nut 126 and the direction of rotation between the second ball screw 125 and the second screw nut 126 are all related. , this application does not specifically limit this, as long as the valve core 1224 can be reset to the initial state when the piston rod 112 is extended or retracted.

Fifth, this embodiment does not specifically limit the position where the connecting rod 130 and the piston rod 112 are fixedly connected. For example, the connecting rod 130 can be set at the end of the piston rod 112, or can be set at other suitable positions, as long as it is not The connection between the piston rod 112 and other transmission components and the retraction of the piston rod 112 can be affected.

The digital hydraulic cylinder 100 provided by the embodiment of the present invention facilitates the integrated control of the hydraulic cylinder through the hydraulic cylinder body 110 and the through-hole components provided on the hydraulic cylinder body 110 without changing the internal structure of the hydraulic cylinder. One end of the first ball screw 123 is fixedly connected to the output end of the driving motor 121, and the other end is drivingly connected to the first screw nut 124. When the driving motor 121 moves according to the pulse signal, the output end of the driving motor 121 drives the The first ball screw 123 moves synchronously, and the rotation of the first ball screw 123 drives the first screw nut 124 to move along the axis of the first ball screw 123 . Since the first screw nut 124 is connected to the first end of the valve core 1224, the first screw nut 124 drives the valve core 1224 to move axially when it moves, and the axial movement of the valve core 1224 causes the first oil passage on the valve body 1222 to pass through. The hole 1226 is communicated with the rod chamber 1112 , and the second oil passage through hole 1228 is communicated with the rodless chamber 1114 , thereby forming a hydraulic passage to drive the piston rod 112 to move. When the piston rod 112 moves, the helical rack 127 fixedly connected to the piston rod 112 through the connecting rod 130 moves synchronously with the piston rod 112. Since the helical rack 127 meshes with the helical teeth provided in the circumferential direction of the second lead screw nut 126 for transmission, the piston When the rod 112 moves, it drives the second lead screw nut 126 to rotate. The second ball screw 125 is connected with the second screw nut 126 in a transmission connection. When the second screw nut 126 rotates, the second ball screw 125 moves axially, thereby driving the valve core 1224 to move axially, and the movement direction is related to the driving direction. The motor 121 drives the spool 1224 to move in the opposite direction to form a mechanical negative feedback. In this way, the hydraulic passage can be closed, thereby stopping the movement of the piston rod 112 . The above movement is a micro-step of the movement of the digital hydraulic cylinder 100. If the piston rod 112 needs to move continuously, a pulse signal needs to be sent to the drive motor 121 at a specific frequency. Whenever the drive motor 121 receives the pulse signal, the spool 1224 is controlled to move , to open the oil passage hole by a small displacement to form a hydraulic passage. The high pressure oil pushes the piston rod 112 to move the corresponding distance and closes the oil passage hole, so that the piston rod 112 stops. When working, the digital hydraulic cylinder 100 continues this action. to complete the required amount of advancement. Through the above structure, precise control of the hydraulic cylinder can be achieved without changing the internal structure of the hydraulic cylinder, thereby simplifying the installation structure and facilitating later maintenance.

As shown in FIG. 2 , the regulating assembly 120 further includes a first coupling 128 and a second coupling 129 . The first screw nut 124 is connected to the first end of the valve core 1224 through the first coupling 128 , and the second The ball screw 125 is connected with the second end of the valve core 1224 through the second coupling 129 .

Specifically, the first screw nut 124 includes a connection cavity connected with the first ball screw 123 and a connection end connected with the first coupling 128 . When the first screw nut 124 is connected with the first ball screw 123 When there is relative rotation between the first screw nut 124 and the first ball screw 123, there is a movable margin between the first screw nut 124 and the first ball screw 123. Since the relative movement distance between the first screw nut 124 and the first ball screw 123 is small each time, This structure does not affect normal transmission. Since the first screw nut 124 and the first end of the valve core 1224 are the connection between the shaft and the shaft, the first coupling 128 can make the connection between the first screw nut 124 and the first end of the valve core 1224 more convenient reliable. Similarly, since the second end of the second ball screw 125 and the valve core 1224 is the connection between the shaft and the shaft, the second ball screw 125 can be connected to the second end of the valve core 1224 through the second coupling 129 The connection is more convenient and reliable.

In order to avoid using other couplings, the valve core 1224 may be rotated during axial movement, and the sealing between the valve body 1222 and the valve core 1224 may be affected, in the preferred embodiment of this embodiment, the first coupling 128 and the second coupling 129 are both universal joints 140 . As shown in FIG. 3 , the universal joint 140 of this embodiment includes a first connecting portion 142 , a second connecting portion 144 and a rotating portion 146 , wherein one end of the first connecting portion 142 and one end of the second connecting portion 144 are The connection is rotated by the rotating part 146 . In this embodiment, the universal joint 140 specifically refers to a coupling in which the first connecting portion 142 and the second connecting portion 144 can be rotatably connected, and a shaft hole can pass between the first connecting portion 142 and the second connecting portion 144 In the form of matching, other forms such as bearings 1262 can also be used to realize the rotational connection between the first connecting portion 142 and the second connecting portion 144, and the position can be limited by a circlip. During assembly and use, the other end of the first connecting portion 142 and the other end of the second connecting portion 144 are respectively connected with the two components to be connected, for example, the first screw nut 124 and the first end of the valve core 1224 are connected , or connect the second ball screw 125 with the second end of the valve core 1224 . In this way, when the first ball screw 123 or the second ball screw 125 rotates, the valve core 1224 is prevented from rotating synchronously with the first ball screw 123 or the second ball screw 125, which is beneficial to improve the sealing of the spool valve 122 sex.

As shown in FIG. 4 , the inner wall of the valve body 1222 is provided with a limiting groove 1222a, and the valve core 1224 is correspondingly provided with a limiting protrusion 1224a matched with the limiting groove 1222a. Please refer to FIG. 5 again. In this embodiment, The inner wall of the valve body 1222 can also be provided with a protrusion 1222b, and the valve core 1224 is correspondingly provided with a groove 1224b matched with the protrusion 1222b, so that the valve core 1224 can only move along the axial direction of the valve core 1224.

It should be noted that the extending direction of the limiting groove 1222a or the protrusion 1222b needs to be consistent with the axial direction of the valve core 1224 to ensure that the valve core 1224 does not rotate itself when moving along the axial direction of the valve core 1224 . When the valve core 1224 moves axially, the rotating part 146 rotates to ensure the normal transmission.

As shown in FIG. 1 and FIG. 6 , the hydraulic cylinder body 110 is provided with a chute 114 along the axis of the valve core 1224 , the helical rack 127 is provided with a slide rail 1272 correspondingly, or, the hydraulic cylinder body 110 is provided along the valve core 1224 A guide slide rail 1272 is provided in the direction of the axis, and a guide slide groove 114 is correspondingly provided on the helical rack 127 , so that the helical rack 127 slides along the direction of the axis of the valve core 1224 .

In this way, when the piston rod 112 is extended or retracted, the helical rack 127 can be ensured to slide along a specific track, so as to prevent the helical rack 127 from skewing, so as not to affect the circumferential direction of the helical rack 127 and the second screw nut 126 The set helical teeth mesh normally. Through the above structure, it can be ensured that the linear motion of the helical rack 127 is converted into the rotational motion of the second screw nut 126 , thereby driving the second ball screw 125 to move axially. In this embodiment, the helical rack 127 specifically refers to a rack that can normally mesh with the helical teeth provided in the circumferential direction of the second lead screw nut 126 .

In an optional solution of this embodiment, the cross section of the chute 114 or the guide chute 114 is trapezoidal or rectangular. Specifically, when the cross section of the chute 114 is trapezoidal, the corresponding slide rail 1272 on the helical rack 127 is also trapezoidal, so that the chute 114 forms a structure of a dovetail groove, which can further play a role in the helical rack 127 The role of limit. When the cross-section of the guide chute 114 is rectangular, the guide rail 1272 correspondingly provided on the helical rack 127 is also rectangular. The helical rack 127 is limited to ensure the stability of the helical rack 127 during movement.

As shown in FIG. 2 , the regulating assembly 120 further includes a bearing 1262 , and the bearing 1262 is disposed between the second screw nut 126 and the valve body 1222 , so that the second screw nut 126 and the valve body 1222 are rotatably connected. Specifically, the outer ring of the bearing 1262 is fixedly connected to the inner wall of the valve body 1222, and the inner ring of the bearing 1262 is fixedly connected to the second screw nut 126. At the same time, the bearing 1262 can also be axially limited by a circlip to ensure The stability of the connection is more stable and reliable when the second lead screw nut 126 is rotated.

As shown in FIG. 2 , the end of the first ball screw 123 away from the first screw nut 124 is provided with a connecting seat 1232 , and the first ball screw 123 is fixedly connected to the output end of the driving motor 121 through the connecting seat 1232 . Specifically, the side of the connection seat 1232 may be provided with fixing holes, so as to facilitate connection and positioning from the side by means of bolts. The connection seat 1232 facilitates the connection and fixation of the first ball screw 123 and the output end of the drive motor 121, which is beneficial to simplify the installation form.

As shown in FIG. 2 , the control assembly 120 further includes a protective shell 150 , the protective shell 150 is disposed on the side of the valve body 1222 close to the driving motor 121 , and the driving motor 121 , the first ball screw 123 , and the first screw nut 124 are all Inside the protective case 150 . In this way, stable connection of the drive motor 121 and the first ball screw 123, the first screw nut 124 and other transmission parts can be ensured during use, so as to ensure the stability during operation and reduce the influence of external interference.

The embodiment of the present invention also provides an excavator, which includes a working arm and a bucket connected to each other, and a digital hydraulic cylinder 100 according to any one of the above. The digital hydraulic cylinder 100 is arranged on the working arm and is drivingly connected with the bucket. The excavator includes the same structure and beneficial effects as the digital hydraulic cylinder 100 in the foregoing embodiment. The structure and beneficial effects of the digital hydraulic cylinder 100 have been described in detail in the foregoing embodiments, and will not be repeated here.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims (10)

1. A digital hydraulic cylinder, characterized in that it comprises a hydraulic cylinder body and a control assembly arranged on the hydraulic cylinder body; the hydraulic cylinder body comprises a cylinder body and a piston rod arranged in the cylinder body, so The piston rod divides the cylinder into a rod cavity and a rodless cavity; the control assembly includes a drive motor capable of receiving pulse signals, a slide valve, a first ball screw, a first screw nut, and a second ball screw A rod and a second lead screw nut, the slide valve includes a valve body arranged on the hydraulic cylinder body and a valve core arranged in the valve body, the valve core can move axially along the valve body; One end of the first ball screw is fixedly connected with the output end of the driving motor, and the other end is drivingly connected with the first screw nut, and the first screw nut is connected with the first end of the valve core; One end of the second ball screw is connected to the second end of the valve core, the second ball screw is drivingly connected to the second screw nut, and the second screw nut is connected to the valve body The valve body is provided with a plurality of oil passage through holes, wherein the first oil passage through hole in the plurality of oil passage through holes communicates with the rod cavity, and the plurality of oil passages communicate with each other. The second oil passage through hole in the hole is communicated with the rodless cavity; the second lead screw nut is circumferentially provided with helical teeth, and the hydraulic cylinder body is also provided with an oblique tooth sliding in the direction of the axis where the valve core is located. A rack, the helical rack is meshed with the helical teeth for transmission, and the helical rack is fixedly connected to the piston rod through a connecting rod. 2 . The digital hydraulic cylinder according to claim 1 , wherein the regulating assembly further comprises a first coupling and a second coupling, and the first screw nut passes through the first coupling. 3 . is connected with the first end of the valve core, and the second ball screw is connected with the second end of the valve core through the second coupling. 3 . The digital hydraulic cylinder according to claim 2 , wherein the first coupling and the second coupling are both universal couplings. 4 . 4 . The digital hydraulic cylinder according to claim 3 , wherein the valve inner wall is provided with a limiting groove, and the valve core is correspondingly provided with a limiting protrusion matched with the limiting groove, 4 . Or the inner wall of the valve body is provided with a protrusion, and the valve core is correspondingly provided with a groove matched with the protrusion, so that the valve core can only move along the axis direction of the valve core. 5 . The digital hydraulic cylinder according to claim 1 , wherein a sliding groove is provided on the hydraulic cylinder body along the direction of the spool axis, and a sliding rail is correspondingly provided on the helical rack, or, 5 . A guide slide rail is provided on the hydraulic cylinder body along the direction of the valve core axis, and a guide slide groove is correspondingly provided on the helical rack, so that the helical gear rack slides along the direction of the valve core axis. 6 . The digital hydraulic cylinder according to claim 5 , wherein the cross section of the chute or the guide chute is trapezoidal or rectangular. 7 . 7. The digital hydraulic cylinder according to claim 1, wherein the regulating assembly further comprises a bearing, and the bearing is arranged between the second screw nut and the valve body, so that the first Two lead screw nuts are rotatably connected with the valve body. 8 . The digital hydraulic cylinder according to claim 1 , wherein a connection seat is provided at one end of the first ball screw away from the first screw nut, and the first ball screw is connected through the connection. 9 . The seat is fixedly connected with the output end of the drive motor. 9 . The digital hydraulic cylinder according to claim 1 , wherein the control assembly further comprises a protective shell, the protective shell is arranged on the side of the valve body close to the drive motor, and the drive motor , The first ball screw and the first screw nut are located in the protective shell. 10. An excavator, characterized by comprising a working arm and a bucket connected to each other, and the digital hydraulic cylinder according to any one of claims 1-9, wherein the digital hydraulic cylinder is arranged on the working arm, and is drivingly connected with the bucket.

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