A replaceable cam diesel valve tester

Abstract

The application discloses a replaceable cam diesel engine valve tester, and belongs to the technical field of diesel engine testing equipment. The replaceable cam structure is used to realize the uniform installation of test cams with different shape parameters on the top of a valve rod, the position of a tappet is fixed through a clamping piece, the convex surface direction of the test cam is fixed through an elastic pin, the arc surface of the test cam contacts the end surface of the tappet through a moving shell frame, the initial position of the test cam is determined through the positioning of the test cam and the tappet and the fixation of a locking part, the device has high universality, the driving test of different test cams and valves can be realized only by replacing the test cam, the support structure of the test cam is correctly positioned during the installation of the test cam, and the support structure specially designed and manufactured for different test cams is not needed, thereby saving equipment occupation and reducing the difficulty of test part replacement.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of diesel engine test equipment, and particularly relates to a diesel engine valve tester with replaceable cam. BACKGROUND

[0002] In the structure of a diesel engine, a valve is an indispensable mechanical structure, which is a valve structure arranged at the inlet and outlet positions of a cylinder body to block and communicate gas. The valve is pressed by a tappet at the top end thereof in the rotating process of a cam, and a spring supports the tappet of the valve, so that the valve moves with the cam to open and close. The cam is a main structure for driving the valve to move, and the diameter and convex arc of the cam are main factors affecting the opening time and rhythm of the valve. In the process of research and development, a preliminary test needs to be performed to obtain different cam driving data by driving the valve with cams of different parameters.

[0003] In the test process, the initial closing position of the valve is fixed, and different support structures need to be replaced for cams of different diameters and convex arcs, so that the rotation of the cam can correctly drive the valve to close. However, the replacement of the support structure is difficult and time-consuming, and the equipment occupies a large space, which brings many obstacles to the test. SUMMARY

[0004] Therefore, the present application aims to provide a diesel engine valve tester with replaceable cam, which can realize correct positioning of the cam by only replacing the cam.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme.

[0006] The present application comprises a simulation cylinder, wherein a valve rod movable back and forth is arranged on the simulation cylinder, a tappet is arranged at the top end of the valve rod, a valve positioning mechanism and a cam engaging mechanism are arranged; the valve positioning mechanism comprises a horizontally movable slide rod, a clamping piece is arranged at the end of the slide rod, the clamping piece is extended and supported at the bottom of the tappet; the cam engaging mechanism comprises a guide rod in the same direction as the moving direction of the valve rod, a shell frame is arranged movable along the guide rod, a locking part is arranged in the shell frame to fix the shell frame on the guide rod, a driving motor is arranged in the shell frame, a cam fixing shaft is arranged at the output end of the driving motor, a test cam is fixed on the cam fixing shaft, the test cam is located at the position facing the top end of the tappet, an extension rod is slidably arranged on the shell frame, an elastic pin is arranged at the end of the extension rod, a sink is arranged on the inner side of the test cam, the extension rod is extended, and when the elastic pin is clamped into the sink by rotating the test cam, the cam surface of the test cam faces the tappet.

[0007] Further, the telescopic device is arranged in parallel with the moving direction of the valve rod, and a stop table is arranged at the output end of the telescopic device, the guide rod is fixed on the stop table, when the telescopic device is extended, the stop table pushes the shell frame outward, when the telescopic device is retracted, the test cam arc surface is supported on the outer end surface of the tappet, and the stop table is separated from the shell frame.

[0008] Further, the locking part comprises two gears arranged in the shell frame, and the two gears are arranged on the two sides of the guide rod and are engaged with each other, and the locking part further comprises a locking rack and a sliding groove, the locking rack is arranged in the sliding groove, and the sliding groove is arranged in the shell frame, and the locking rack is engaged with the two gears when the sliding groove is moved.

[0009] Further, the elastic element is arranged between the two ends of the locking rack and the sliding groove.

[0010] Further, a rotating motor is arranged in the shell frame, a threaded column is arranged at the end of the rotating motor, a threaded cylinder is arranged at the bottom end of the sliding groove, the threaded cylinder is threadedly connected with the threaded column, and the rotating motor is rotated to drive the sliding groove to move away from or close to the gears.

[0011] Further, a driving electric cylinder is arranged in the shell frame, the driving electric cylinder is connected with the telescopic rod, and the driving electric cylinder drives the telescopic rod to move.

[0012] Further, the clamping piece is in a U-shaped structure, and the end surface edge of the clamping piece is chamfered.

[0013] The present application has the following advantages:

[0014] The present application has the following advantages:

[0015] Additional advantages, objects, and features of the application will be set forth in part by the description that follows, and in part will become apparent to those skilled in the art upon examination of the following or can be learned from practice of the application. The objectives and other advantages of the application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0016] To make the objectives, technical solutions and beneficial effects of the present application clearer, the present application is provided with the following drawings for illustration:

[0017] Figure 1 It is a structural schematic view of a test machine of the embodiment of the present application;

[0018] Figure 2 It is a sectional view at the telescopic rod of the embodiment of the present application;

[0019] Figure 3 It is a structural schematic view of a test cam of the embodiment of the present application;

[0020] Figure 4 It is a first internal structural schematic view of the test machine of the embodiment of the present application;

[0021] Figure 5 It is a second internal structural schematic view of the test machine of the embodiment of the present application;

[0022] Figure 6 It is a structural schematic view of a valve positioning mechanism of the embodiment of the present application;

[0023] In the drawings, the following marks are used: 1, simulation cylinder; 2, valve rod; 21, tappet; 3, valve positioning mechanism; 31, sliding rod; 32, clamping piece; 4, cam engaging mechanism; 41, guide rod; 42, shell frame; 43, locking part; 431, gear; 432, locking rack; 433, sliding groove; 434, elastic piece; 435, rotating motor; 436, threaded column; 437, threaded cylinder; 44, driving motor; 441, cam fixing shaft; 45, telescopic rod; 451, elastic pin; 46, telescopic device; 461, blocking table; 47, driving cylinder; 5, test cam; 51, sink groove. DETAILED DESCRIPTION

[0024] As Figures 1-6As shown, the present application discloses a replaceable cam diesel valve tester, including a simulation cylinder 1, the simulation cylinder 1 is used to simulate the diesel cylinder, the simulation cylinder has a gas passage, the gas passage is provided with a reciprocating valve rod 2, the valve rod 2 is vertically arranged, according to the structure of the test diesel engine, the corresponding deflection is made, the valve rod 2 top end is provided with a tappet 21, the tappet 21 is used to contact with the test cam 5, the blocking disc is arranged between the upper end section of the valve rod 2, the spring is supported between the blocking disc and the simulation cylinder, the above structure constitutes the basic valve test environment, through installing different test cams 5, the test is carried out, the structure of the test cam 5 replacement includes a valve positioning mechanism 3 and a cam engaging mechanism 4. Figure 1 As shown, the valve positioning mechanism 3 includes a horizontal moving slide rod 31, the horizontal moving slide rod 31 can be driven by a reciprocating driving device such as an electric cylinder, a motor and the like, or manual sliding is adopted; the end of the slide rod 31 is provided with a clamping piece 32, when the clamping piece 32 is extended, the clamping piece 32 is supported at the bottom of the tappet 21, at this time, the movement of the valve rod 2 is locked and limited, and the position of the tappet 21 is statically fixed. Figure 1 As shown, the cam engaging mechanism 4 includes a guide rod 41 which is the same as the moving direction of the valve rod 2, a shell frame 42 is movably arranged along the guide rod 41, a locking part 43 is arranged in the shell frame 42 to fix the shell frame 42 on the section of the guide rod 41, as shown in Figure 1 and Figure 2 , a driving motor 44 is arranged in the shell frame 42, a cam fixing shaft 441 is arranged at the output end of the driving motor 44, the cam fixing shaft 441 can adopt a spline and nut locking structure, so as to ensure that the cam will not slip in the rotating process driven by the driving motor 44, the test cam 5 is fixed on the cam fixing shaft 441 and rotates with the driving motor 44, the test cam 5 is located at the top end of the tappet 21 towards position, a telescopic rod 45 is slidably arranged on the shell frame 42, an elastic pin 451 is arranged at the end of the telescopic rod 45, a recess 51 is arranged in the inner side of the test cam 5 as shown in Figure 3 , the recess 51 is arranged along the radial direction of the test cam 5, the recess 51 of the structure is arranged on the test cam 5 which needs to be tested, when the telescopic rod 45 is extended and the test cam 5 is rotated to make the elastic pin 451 clamped into the recess 51, the arc surface of the test cam 5 faces the tappet 21, and the convex end of the test cam 5 is away from the end surface of the tappet 21.

[0025] The operation mode of the test machine is as follows: first, move the slide rod 31 to make the clamping piece 32 clamped under the lower end of the tappet 21, fix the tappet 21, move the shell frame 42 along the guide rod 41 to make the shell frame 42 away from the tappet 21 at a height, fix the test cam 5 to be tested at the cam fixing shaft 441 of the driving motor 44, extend the telescopic rod 45, and rotate the test cam 5, when the elastic pin 451 is clamped into the said sink groove 51, the arc surface of the test cam 5 faces the said tappet 21, then move the shell frame 42 downward, the shell frame 42 drives the cam to move towards the tappet 21, the arc surface of the test cam 5 contacts the end surface of the tappet 21, the position of the shell frame 42 is limited, at this time, the shell frame 42 is fixed at this position through the locking part 43, the slide rod 31 and the telescopic rod 45 are retracted, and the test of the test cam 5 can be started.

[0026] Through the replacement structure of the test cam 5, different shape parameters of the test cam 5 are uniformly installed on the air valve rod 2 by the same device, the position of the tappet 21 is fixed through the clamping piece 32, the convex surface of the test cam 5 is fixed through the elastic pin 451, the arc surface of the test cam 5 contacts the end surface of the tappet 21 by moving the shell frame 42, the initial position of the test of the test cam 5 is determined through the positioning of the test cam 5 and the tappet 21 and the fixing of the locking part 43, that is, when the arc surface of the test cam 5 contacts the end surface of the tappet 21, the air valve is in a closed state, the convex surface of the test cam 5 opens the air valve, and the arc surface closes the air valve, the device has strong universality, different test cams 5 and air valves can be driven and tested by replacing the test cam 5 only, the support structure of the test cam 5 completes the correct positioning when the test cam 5 is installed, and there is no need to design and manufacture a special support structure for different test cams 5, thereby saving equipment occupation and test part replacement difficulty.

[0027] In a further scheme, as shown in Figure 1 Fig. 6, a telescopic device 46 is further included, which can be a hydraulic cylinder, an electric cylinder or the like, the telescopic direction of the telescopic device 46 is parallel to the moving direction of the air valve rod 2, the output end of the telescopic device 46 is provided with a stop table 461, the guide rod 41 is fixed on the stop table 461, when the telescopic device 46 is extended, the stop table 461 pushes the shell frame 42 outward, when the telescopic device 46 is retracted, the arc surface of the test cam 5 is supported on the outer end surface of the tappet 21, and the stop table 461 is away from the shell frame 42.

[0028] By adding the telescopic device 46, the direct movement of the shell frame 42 is replaced, the telescopic device 46 moves the shell frame 42 upward through the stop table 461 when it is extended, and the stop table 461 is away from the shell frame 42 when it is retracted, so as to realize the positioning of the test cam 5 and the tappet 21, this structure can replace the manual upward movement of the heavy shell frame 42, save labor, and the shell frame 42 is always supported during the movement process, so as to avoid the damage caused by the falling of the shell frame 42.

[0029] Further, as shown in Figure 4 and Figure 5 The locking portion 43 includes two gears 431 rotatingly arranged inside the shell frame 42, and the two gears 431 are respectively clamped and engaged on both sides of the guide rod 41. A plurality of gears 431 can also be arranged to be clamped and engaged on both sides of the guide rod 41, so that the shell frame 42 can be stably moved along the guide rod 41. Referring to Figure 4 , a total of four gears 431 are arranged, and the two gears 431 are clamped on both sides of the guide rod 41, so that the shell frame 42 is positioned by the gears 431 and will not be inclined during movement. The two gears 431 located at the lower position have a wider width, and one end of the gear 431 extends out from the outside of the guide rod 41. A locking rack 432 and a sliding groove 433 are arranged below the extending gear 431. The locking rack 432 is slidingly arranged in the sliding groove 433, and the sliding groove 433 is movably arranged in the shell frame 42. The sliding groove 433 is moved, and the locking rack 432 is displaced in the sliding groove 433 to make the locking rack 432 engage with the two gears 431 at the same time.

[0030] After the locking rack 432 engages with the two gears 431, the two locking gears 431 are limited to rotate, forming a self-locking structure. The gear 431 engages with the guide rod 41 and the locking rack 432 at the same time, so that the shell frame 42 can be fixed at any position on the guide rod 41. The structure of the gear 431 engagement and locking ensures smooth movement of the shell frame 42 during movement, and complete fixation during fixation, avoiding slipping and other phenomena during the test, causing the shell frame 42 to move and resulting in test failure.

[0031] Further, as shown in Figure 5 , the elastic members 434 are arranged between the two ends of the locking rack 432 and the sliding groove 433. The elastic members 434 can be selected from a plurality of springs. The springs arranged on both sides of the locking rack 432 can ensure that the locking rack 432 is located in the middle of the sliding groove 433 in the disengaged state, and can be left and right to engage and lock the two gears 431 in the engaged state. The arrangement of the elastic members 434 avoids the limitation of the two ends of the locking rack 432, so that the locking rack 432 cannot be engaged.

[0032] Further, as shown in Figure 5As shown, the shell frame 42 is provided with a rotating motor 435, the rotating motor 435 is provided with a threaded column 436 at the end, the chute strip 433 is provided with a threaded cylinder 437 at the bottom end, the threaded cylinder 437 is threadedly connected with the threaded column 436, the rotating motor 435 rotates to drive the chute strip 433 to move away from and close to the gear 431, and a guide pin can be arranged at the bottom end of the chute strip 433 to ensure smooth movement of the chute strip 433. In this structure, through the rotation of the rotating motor 435 and the threaded connection, the movement of the chute strip 433 can be realized by the forward and reverse rotation of the rotating motor 435, and through the threaded locking, the chute strip 433 is fixed at any position, avoiding the movement of the locking rack 432 on the chute strip 433.

[0033] In a further scheme, as Figure 2 , the shell frame 42 is provided with a driving electric cylinder 47, the driving electric cylinder 47 is connected with the telescopic rod 45, the driving electric cylinder 47 drives the telescopic rod 45 to extend and retract, the driving electric cylinder 47 can quickly drive the telescopic rod 45 to extend and retract, realizing the positioning of the elastic pin 451 to the test cam 5.

[0034] In a further scheme, the clamping piece 32 is in a U-shaped structure, the end face edge of the clamping piece 32 towards the tappet 21 is chamfered, the U-shaped clamping piece 32 can stably support the bottom end of the tappet 21, and the chamfered end face of the tappet 21 can avoid interference when the clamping piece 32 is inserted into the lower end of the tappet 21.

[0035] Finally, it should be explained that the above preferred embodiments are only used to illustrate the technical solutions of the present application and are not limited, although the present application has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made in form and details without departing from the scope defined by the claims of the present application.

Claims

1. A replaceable cam diesel valve tester, comprising a simulation cylinder (1) provided with a reciprocating valve rod (2) on the simulation cylinder (1), and a tappet (21) provided at the top end of the valve rod (2), characterized in that: The application relates to a valve positioning mechanism (3) and a cam engaging mechanism (4); the valve positioning mechanism (3) comprises a horizontally-moving slide rod (31), the end of the slide rod (31) is provided with a clamping piece (32), the clamping piece (32) is supported on the bottom of a tappet (21), the cam engaging mechanism (4) comprises a guide rod (41) which is parallel to the moving direction of a valve rod (2), a shell frame (42) is movably arranged on the guide rod (41), the shell frame (42) is provided with a locking part (43) for fixing the shell frame (42) on the guide rod (41), a driving motor (44) is arranged in the shell frame (42), the output end of the driving motor (44) is provided with a cam fixing shaft (441), a test cam (5) is fixed on the cam fixing shaft (441), the test cam (5) is located at the top end of the tappet (21) and faces a position, a telescopic rod (45) is slidably arranged on the shell frame (42), the end of the telescopic rod (45) is provided with an elastic pin (451), the inner side of the test cam (5) is provided with a sink (51), the telescopic rod (45) is extended, and when the elastic pin (451) is clamped into the sink (51) by rotating the test cam (5), the arc surface of the test cam (5) faces the tappet (21).

2. The replaceable cam diesel valve tester of claim 1, wherein: The application further comprises a telescopic device (46), the telescopic direction of the telescopic device (46) is parallel to the moving direction of the valve rod (2), the output end of the telescopic device (46) is provided with a stop table (461), the guide rod (41) is fixed on the stop table (461), when the telescopic device (46) is extended, the stop table (461) pushes the shell frame (42) out, when the telescopic device (46) is retracted, the arc surface of the test cam (5) is supported on the outer end surface of the tappet (21), and the stop table (461) is separated from the shell frame (42).

3. The replaceable cam diesel valve tester of claim 1, wherein: The locking part (43) comprises two gears (431) which are rotatably arranged in the shell frame (42), the two gears (431) are respectively clamped and engaged on the two sides of the guide rod (41), the locking part (43) further comprises a locking rack (432) and a sliding groove (433), the locking rack (432) is slidably arranged in the sliding groove (433), the sliding groove (433) is movably arranged in the shell frame (42), and when the sliding groove (433) is moved, the locking rack (432) simultaneously engages the two gears (431).

4. The replaceable cam diesel valve tester of claim 3, wherein: Elastic elements (434) are arranged between the two ends of the locking rack (432) and the sliding groove (433).

5. The replaceable cam diesel valve tester of claim 3, wherein: A rotating motor (435) is arranged in the shell frame (42), the end of the rotating motor (435) is provided with a threaded column (436), the bottom end of the sliding groove (433) is provided with a threaded cylinder (437), the threaded cylinder (437) is threadedly connected with the threaded column (436), and the rotating motor (435) is rotated to drive the sliding groove (433) to move away from and close to the gears (431).

6. The replaceable cam-type diesel valve tester of claim 1, wherein: The shell frame (42) is internally provided with a driving electric cylinder (47), the driving electric cylinder (47) is connected with the telescopic rod (45), and the driving electric cylinder (47) drives the telescopic rod (45) to perform telescopic movement.

7. The replaceable cam-type diesel valve tester of claim 1, wherein: The clamping piece (32) is in a U-shaped structure, and the end face edge of the clamping piece (32) is chamfered towards the tappet head (21).

Images